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The following is an excerpt from a S-3 SEC Filing, filed by WELLS FARGO ASSET SECURITIES CORP on 5/20/2008.
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WELLS FARGO ASSET SECURITIES CORP - S-3 - 20080520 - SUBJECT_STOCK_INFO

SUBJECT TO COMPLETION DATED MAY 20, 2008

PROSPECTUS SUPPLEMENT
(To Prospectus Dated , 20 )

[WELLS FARGO LOGO]

Wells Fargo Asset Securities Corporation
Depositor

Wells Fargo Bank, N.A.
Sponsor and Master Servicer

Wells Fargo Alternative Loan 20 - Trust
Issuing Entity

$[________________________]
(Approximate)

Mortgage Asset-Backed Pass-Through Certificates, Series 20 - Principal and interest payable monthly, commencing in [_____] 20


You should carefully consider the risk factors beginning on page S-[17] of this prospectus supplement. Neither the offered certificates nor the underlying mortgage loans are insured or guaranteed by any governmental agency or instrumentality or any other entity.

The offered certificates will represent interests in the assets deposited with the issuing entity only and will not represent interests in or obligations of the depositor, the sponsor or any other entity.

This prospectus supplement may be used to offer and sell the offered certificates only if accompanied by the prospectus.


The Issuing Entity Will Issue--

o Seventeen classes of senior certificates.

o Six classes of subordinated certificates, all of which are subordinated to, and provide credit enhancement for, the senior certificates. Each class of subordinated certificates is also subordinated to each class of subordinated certificates, if any, with a lower number.

The classes of offered certificates are listed and their sizes and basic payment characteristics are described under the heading "Offered Certificates" in the table beginning on page S-6.

The Assets of the Issuing Entity Will Include--

o A pool of fully amortizing, one- to four-family, fixed interest rate, residential first mortgage loans (excluding the fixed retained yield described in this prospectus supplement), substantially all of which have original terms to stated maturity of approximately 30 years.

Credit Enhancement Will Consist Of--

o Subordination of the subordinated certificates to the senior certificates for the distributions of principal and interest and the allocation of losses.

o Shifting interest in prepayments through the allocation, subject to certain exceptions, of most principal collections to the senior certificates for the first five years and a lesser, but still disproportionately large, allocation of these collections to the senior certificates during the following four years.

o In the case of each class of super senior certificates, the subordination of the related class of super senior support certificates for losses if the subordinated certificates are no longer outstanding.

Neither the SEC nor any state securities commission has approved the certificates offered by this prospectus supplement or determined that this prospectus supplement or the prospectus is accurate or complete. Any representation to the contrary is a criminal offense.

The underwriter will purchase the offered certificates from the depositor and offer them to investors at varying prices to be determined at the time of sale. The offered certificates will be available for delivery to investors on or about
[_____], 20 . Classes in book entry form will be made available through The Depository Trust Company, Clearstream International or the Euroclear System. Total proceeds to the depositor for the offered certificates will be approximately $[_____] before deducting expenses estimated at $[_____] plus accrued interest from [_____], 20 to [_____], 20 .

[Underwriter]

The date of this prospectus supplement is [_____], 20


TABLE OF CONTENTS

                              PROSPECTUS SUPPLEMENT

IMPORTANT NOTICE ABOUT INFORMATION PRESENTED IN THIS PROSPECTUS
  SUPPLEMENT AND THE ACCOMPANYING PROSPECTUS...............................S-4
SUMMARY INFORMATION........................................................S-8
RISK FACTORS..............................................................S-17
  "Alternative A"  Mortgage Loans May Experience Greater Rates of
    Delinquency and Foreclosure Due to Underwriting Standards.............S-17
  Decline in Residential Real Estate Values May Increase Risk of
    Loss and Adversely Affect Your Investment.............................S-17
  Mortgage Securities Market Illiquidity May Adversely Affect the
    Value of Your Certificates............................................S-17
  Prepayments May Adversely Affect Yield..................................S-18
  Geographic Concentration May Increase Risk of Loss Because of
    Adverse Economic Conditions or Natural Disasters......................S-19
  High Balance Loans May Increase Risk of Loss on Certificates............S-19
  Lack of income or asset verification may increase risk of loss..........S-19
  Delinquencies and Losses on the Mortgage Loans Will Adversely
    Affect Your Yield.....................................................S-20
  Subordination of Super Senior Support Certificates and the
    Class B Certificates Increases Risk of Loss...........................S-20
  Interest Only Mortgage Loans May Have Higher Risk of Default or
    Rates of Prepayment...................................................S-21
  The Rate of Default on Mortgage Loans that are Secured by
    Investor Properties May be Higher than on Other Mortgage Loans........S-21
  FICO Scores May Not Accurately Predict the Likelihood of Default........S-21
  Decrement and Sensitivity Tables are Based Upon Assumptions and
    Models................................................................S-21
  Residual Certificates May Have Adverse Tax Consequences.................S-22
  United States Military Operations May Increase Risk of Relief
    Act Shortfalls........................................................S-22
  Proposed Bankruptcy Amendments May Delay or Reduce Collections
    on Mortgage Loans.....................................................S-22
FORWARD LOOKING STATEMENTS................................................S-23
THE SPONSOR...............................................................S-23
STATIC POOL INFORMATION...................................................S-23
THE DEPOSITOR.............................................................S-24
THE ISSUING ENTITY........................................................S-24
THE TRUSTEE...............................................................S-25
THE MASTER SERVICER.......................................................S-25
THE PAYING AGENT..........................................................S-26
THE SERVICER..............................................................S-26
THE CUSTODIAN.............................................................S-26
ROLES OF WELLS FARGO BANK.................................................S-27
DESCRIPTION OF THE CERTIFICATES...........................................S-27
  General.................................................................S-27
  Book-Entry Certificates.................................................S-27
  Distributions...........................................................S-27
  Interest................................................................S-29
  Principal (Including Prepayments).......................................S-32
  Additional Rights of the Residual Certificateholders....................S-40
  Restrictions on Transfer of the Residual Certificates...................S-40
  Periodic Advances.......................................................S-40
  Subordination of Class B Certificates...................................S-41
  Allocation of Losses....................................................S-41
DESCRIPTION OF THE MORTGAGE LOANS().......................................S-43
  General.................................................................S-43
  Mortgage Loan Data Appearing in Appendix A..............................S-43
  Mortgage Loan Underwriting..............................................S-45
  Mandatory Repurchase or Substitution of Mortgage Loans..................S-46
  Optional Purchase of Mortgage Loans.....................................S-46
[DESCRIPTION OF THE MORTGAGE CERTIFICATES]................................S-46
PREPAYMENT AND YIELD CONSIDERATIONS.......................................S-46
  General.................................................................S-46
  Sensitivities of Certain Classes of Certificates........................S-51
  Yield Considerations with Respect to the Class B-2 and Class
    B-3 Certificates......................................................S-52
POOLING AND SERVICING AGREEMENT...........................................S-53
  General.................................................................S-53
  Compensation and Payment of Expenses of the Master Servicer,
    Servicer and Trustee..................................................S-53
  Optional Termination of the Trust.......................................S-54
  Voting..................................................................S-55
  Fixed Retained Yield....................................................S-55
FEDERAL INCOME TAX CONSIDERATIONS.........................................S-55

                                      S-2

  General.................................................................S-55
  Regular Certificates....................................................S-55
  Residual Certificates...................................................S-56
ERISA CONSIDERATIONS......................................................S-57
LEGAL INVESTMENT..........................................................S-58
SECONDARY MARKET..........................................................S-58
PLAN OF DISTRIBUTION......................................................S-58
LEGAL MATTERS.............................................................S-59
USE OF PROCEEDS...........................................................S-59
RATINGS...................................................................S-59
INDEX OF PROSPECTUS SUPPLEMENT DEFINITIONS................................S-60
APPENDIX A: MORTGAGE LOAN DATA.............................................A-1
APPENDIX B: ASSUMED MORTGAGE LOAN CHARACTERISTICS..........................B-1
APPENDIX C: DECREMENT TABLES...............................................C-1
APPENDIX D: SENIOR SENSITIVITY TABLES......................................D-1
APPENDIX E: SUBORDINATE SENSITIVITY TABLES.................................E-1
APPENDIX F: PLANNED PRINCIPAL BALANCES.....................................F-1

S-3

IMPORTANT NOTICE ABOUT INFORMATION PRESENTED IN THIS
PROSPECTUS SUPPLEMENT AND THE ACCOMPANYING PROSPECTUS

Information is provided to you about the offered certificates in two separate documents that progressively provide more detail:

o the accompanying prospectus, which provides general information, some of which may not apply to your certificates; and

o this prospectus supplement, which incorporates and includes the appendices, and describes the specific terms of your certificates.

Cross-references are included in this prospectus supplement and the accompanying prospectus to captions in these materials where you can find further related discussions. The foregoing table of contents and the table of contents included in the accompanying prospectus provide the pages on which these captions are located.

You can find a listing of the pages where capitalized terms used in this prospectus supplement and the accompanying prospectus are defined under the caption "Index of Prospectus Supplement Definitions" beginning on page S-60 in this document and under the caption "Index of Prospectus Definitions" beginning on page 164 in the accompanying prospectus. Any capitalized terms used but not defined in this prospectus supplement have the meanings assigned in the prospectus.

European Economic Area

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a "Relevant Member State"), the underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State (the "Relevant Implementation Date"), it has not made and will not make an offer of offered certificates to the public in that Relevant Member State prior to the publication of a prospectus in relation to the offered certificates which has been approved by the competent authority in that Relevant Member State or, where appropriate, approved in another Relevant Member State and notified to the competent authority in that Relevant Member State, all in accordance with the Prospectus Directive, except that it may, with effect from and including the Relevant Implementation Date, make an offer of offered certificates to the public in that Relevant Member State at any time:

(a) to legal entities which are authorized or regulated to operate in the financial markets or, if not so authorized or regulated, whose corporate purpose is solely to invest in securities;

(b) to any legal entity which has two or more of (1) an average of at least 250 employees during the last financial year; (2) a total balance sheet of more than (euro)43,000,000 and (3) an annual net turnover of more than (euro)50,000,000, as shown in its last annual or consolidated accounts; or

(c) in any other circumstances which do not require the publication by the issuer of a prospectus pursuant to Article 3 of the Prospectus Directive.

For the purposes of this provision, the expression an "offer of offered certificates to the public" in relation to any offered certificates in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the offered certificates to be offered so as to enable an investor to decide to purchase or subscribe the offered certificates, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State and the expression "Prospectus Directive" means Directive 2003/71/EC and includes any relevant implementing measure in each Relevant Member State.

United Kingdom

The underwriter has represented and agreed that:

S-4

(a) it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the Financial Services and Markets Act 2000 (the "FSMA")) received by it in connection with the issue or sale of the offered certificates in circumstances in which Section 21(1) of the FSMA does not apply to the trust; and

(b) it has complied and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the offered certificates in, from or otherwise involving the United Kingdom.

Notice to United Kingdom Investors

The distribution of this prospectus supplement and the accompanying prospectus, if made by a person who is not an authorized person under the FSMA, is being made only to, or directed only at persons who (1) are outside the United Kingdom, or (2) have professional experience in matters relating to investments, or (3) are persons falling within Articles 49(2)(a) through (d) ("high net worth companies, unincorporated associations, etc.") or 19 (Investment Professionals) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (all such persons together being referred to as the "Relevant Persons"). This prospectus supplement and the accompanying prospectus must not be acted on or relied on by persons who are not Relevant Persons. Any investment or investment activity to which this prospectus supplement and the accompanying prospectus relates, including the offered certificates, is available only to Relevant Persons and will be engaged in only with Relevant Persons.

Potential investors in the United Kingdom are advised that all, or most, of the protections afforded by the United Kingdom regulatory system will not apply to an investment in the offered certificates and that compensation will not be available under the United Kingdom Financial Services Compensation Scheme.

S-5


THE SERIES 20 - CERTIFICATES

                           Initial      Pass-
                          Principal    Through                                           Interest
Class                     Balance(1)    Rate           Principal Types(2)                Types(2)
-----------------------   ----------   -------   -------------------------------   ---------------------
Offered Certificates
Class A-1                                   (7)  Senior, Sequential Pay            Inverse Floating Rate
Class A-2                                   (7)  Senior, Sequential Pay            Floating Rate
Class A-3                                 [_]%   Super Senior, Lockout             Fixed Rate
Class A-4                                 [_]%   Senior, Sequential Pay            Fixed Rate
Class A-5                                   (7)  Senior, Accretion Directed,       Floating Rate
                                                 Planned Amortization II
Class A-6                                   (7)  Senior, Accretion Directed,       Inverse Floating Rate
                                                 Planned Amortization II
Class A-7                                 [_]%   Senior, Planned Amortization II   Accrual, Fixed Rate
Class A-8                                 [_]%   Senior, Accretion Directed,       Fixed Rate
                                                 Companion
Class A-9                                 [_]%   Senior, Companion                 Accrual, Fixed Rate
Class A-10                                [_]%   Senior, Planned Amortization I    Fixed Rate
Class A-11                                [_]%   Senior, Planned Amortization I    Fixed Rate
Class A-12                                [_]%   Super Senior, Planned             Fixed Rate
                                                 Amortization I
Class A-13                                [_]%   Senior, Planned Amortization I    Fixed Rate
Class A-14                                [_]%   Super Senior Support, Planned     Fixed Rate
                                                 Amortization I
Class A-15                                [_]%   Super Senior Support, Lockout     Fixed Rate
Class A-PO                               0.000%  Senior, Ratio Strip               Principal Only
Class A-R                                 [_]%   Senior, Sequential Pay            Fixed Rate
Class B-1                                 [_]%   Subordinated                      Fixed Rate
Class B-2                                 [_]%   Subordinated                      Fixed Rate
Class B-3                                 [_]%   Subordinated                      Fixed Rate
Non-Offered Certificate
Class B-4                                 [_]%   Subordinated                      Fixed Rate
Class B-5                                 [_]%   Subordinated                      Fixed Rate
Class B-6                                 [_]%   Subordinated                      Fixed Rate

                          Initial Rating
                            of Offered                                                      Final Scheduled
                          Certificates(3)     Original     Minimum         Incremental       Distribution
Class                     [_]         [_]      Form(4)   Denomination    Denomination(5)        Date(6)
-----------------------   ---         ---     --------   -------------   ----------------   ---------------
Offered Certificates
Class A-1                                      BE      $               $                    [_____], 20
Class A-2                                      BE      $               $                    [_____], 20
Class A-3                                      BE      $               $                    [_____], 20
Class A-4                                      BE      $               $                    [_____], 20
Class A-5                                      BE      $               $                    [_____], 20

Class A-6                                      BE      $               $                    [_____], 20

Class A-7                                      BE      $               $                    [_____], 20
Class A-8                                      BE      $               $                    [_____], 20

Class A-9                                      BE      $               $                    [_____], 20
Class A-10                                     BE      $               $                    [_____], 20
Class A-11                                     BE      $               $                    [_____], 20
Class A-12                                     BE      $               $                    [_____], 20

Class A-13                                     BE      $               $                    [_____], 20
Class A-14                                     BE      $               $                    [_____], 20

Class A-15                                     BE      $               $                    [_____], 20
Class A-PO                                     BE      $               $                    [_____], 20
Class A-R                                      D       $               $                    [_____], 20
Class B-1                                      BE      $               $                    [_____], 20
Class B-2                                      BE      $               $                    [_____], 20
Class B-3                                      BE      $               $                    [_____], 20
Non-Offered Certificate
Class B-4                                     N/A      N/A             N/A                  [_____], 20
Class B-5                                     N/A      N/A             N/A                  [_____], 20
Class B-6                                     N/A      N/A             N/A                  [_____], 20


(1) Approximate. The initial principal balances are subject to adjustment as described under "Summary Information-Principal Balance of the Certificates" in this prospectus supplement.

(2) See "Description of the Certificates -- Categories of Classes of Certificates" in the prospectus for a description of the principal and interest categories listed.

(3) A description of the ratings of the offered certificates is set forth under the heading "Rating of Certificates" in the Summary Information and under "Ratings" in the main text of this prospectus supplement.

(4) See "Description of the Certificates -- Definitive Form" and "-- Book-Entry Form" in the prospectus for a description of the forms of certificates. Book-entry form is designated as "BE" and definitive form is designated as "D" in the table above.


S-6

(5) If necessary, in order to aggregate the initial principal balance of a class, one certificate of the class will be issued in an incremental denomination of less than that shown.

(6) The final scheduled distribution date represents the distribution date in the month following the latest maturity date of any mortgage loan in the mortgage pool. The actual final payment on your certificates could occur earlier or later than the final scheduled distribution date.

(7) The following table describes the methodology for determining the pass-through rates for each class of floating rate certificates. See "Description of the Certificates-Interest" in this prospectus supplement.

            Initial Pass-       Pass-Through            Minimum        Maximum Pass-
Class       Through Rate        Rate Formula       Pass-Through Rate   Through Rate
---------   -------------   --------------------   -----------------   -------------
Class A-1       [_]%        [ ]% - (LIBOR x [ ])         [_]%              [_]%
Class A-2       [_]%            LIBOR + [ ]%             [_]%              [_]%
Class A-5       [_]%            LIBOR + [ ]%             [_]%              [_]%
Class A-6       [_]%        [ ]% - (LIBOR x [ ])         [_]%              [_]%


S-7


SUMMARY INFORMATION

This summary highlights selected information from this document, but does not contain all of the information that you should consider in making your investment decision. Please read this entire prospectus supplement and the accompanying prospectus carefully for additional detailed information about the offered certificates.

RELEVANT PARTIES

Sponsor

Wells Fargo Bank, N.A.

Depositor

Wells Fargo Asset Securities Corporation.

Master Servicer

Wells Fargo Bank, N.A.

Servicers

Initially, Wells Fargo Bank, N.A. Any other servicer will be approved by the master servicer.

Issuing Entity

The Wells Fargo Alternative Loan 20 - Trust, a New York common law trust.

Trustee

HSBC Bank USA, National Association.

Custodian

Wells Fargo Bank, N.A.

Paying Agent

Wells Fargo Bank, N.A.

AFFILIATIONS

Wells Fargo Bank, N.A., which is the sponsor, custodian, master servicer, servicer and paying agent, is the direct parent of the depositor. There are no relationships, agreements or arrangements outside of this transaction among the affiliated parties that are material to an understanding of the offered certificates.

CUT-OFF DATE

[_____], 20 .

CLOSING DATE

On or about [_____], 20 .

DISTRIBUTION DATES

The 25th day of each month, or the following business day if the 25th day is not a business day, commencing in [_____] 20 .

DETERMINATION DATES

With respect to each distribution date, the 17th day of each month.

THE TRANSACTION PARTIES

The sponsor originated or purchased and currently services the mortgage loans. On the closing date the sponsor will sell the mortgage loans to the depositor, who will in turn deposit them into a common law trust, which is the issuing entity. The trust will be formed by a pooling and servicing agreement, to be dated as of the closing date, among the depositor, the master servicer and the trustee. The master servicer will master service the mortgage loans and calculate distributions and other information regarding the certificates in accordance with the pooling and servicing agreement. The trustee will have limited administrative duties under the pooling and servicing agreement. The servicer will service the mortgage loans in accordance with the underlying servicing agreement entered into between the servicer and the master servicer.


S-8


The transfers of the mortgage loans from the sponsor to the depositor to the issuing entity in exchange for the certificates is illustrated below:

            -------------                  Offered
            |  Sponsor  |                Certificates
            -------------                                   ---------------
Mortgage Loans  |   ^   Cash                --------------> | Underwriter |
                |   |                       |   ----------- ---------------
                v   |                       |  |                  |  ^
            ------------- -------------------  |                  |  |
            | Depositor | <---------------------                  |  |
            -------------                   Cash       Offered    |  |   Cash
                |   ^                                Certificates |  |
Mortgage Loans  |   |   All Certificates                          v  |
                |   |                                       ---------------
                |   |                                       |  Investors  |
                v   |                                       ---------------
            -------------
            | Issuing   |
            |  Entity   |
            -------------

RATING OF CERTIFICATES

The trust will not issue the offered certificates unless they have received at least the ratings set forth in the table beginning on page S-6.

o The ratings of the rating agencies are not recommendations to buy, sell or hold the certificates rated. A rating may be revised or withdrawn at any time by the assigning rating agency.

o The ratings do not address the possibility that, as a result of principal prepayments, the yield on your certificate may be lower than anticipated.

See "-- Effects of Prepayments on Your Investment Expectations" below and "Ratings" in this prospectus supplement.

DESCRIPTION OF CERTIFICATES

A summary chart of the initial principal balances, pass-through rates, principal types, interest types, ratings, original form, denominations and final scheduled distribution dates of the certificates is set forth in the table beginning on page S-6.

The certificates consist of:

o the seventeen classes of senior Class A Certificates designated as "Senior," "Super


S-9


Senior" and "Super Senior Support" certificates in the table beginning on page S-6; and

o the six classes of junior Class B Certificates designated as "Subordinated" certificates in the table beginning on page S-6.

Only the Class A, Class B-1, Class B-2 and Class B-3 Certificates are being offered by this prospectus supplement and the accompanying prospectus. The Class B-4, Class B-5 and Class B-6 Certificates are not being offered pursuant to this prospectus supplement and the accompanying prospectus, and the depositor may retain or sell such classes. Information provided with respect to the Class B-4, Class B-5 and Class B-6 Certificates is included solely to aid your understanding of the offered certificates.

See the table beginning on page S-6 for more information with respect to each class of certificates.

Principal Balance of the Certificates

The certificates will have an approximate total initial principal balance of $[_____]. Any difference between the total principal balance of the certificates as of the date of issuance of the certificates and the approximate total initial principal balance of the certificates as of the date of this prospectus supplement will not exceed 5% of the total initial principal balance of the certificates. Any such difference will be allocated among the various classes of certificates so as to materially retain the characteristics of the offered certificates described in this prospectus supplement.

Interests in Mortgage Loans

The Class A-PO Certificates represent a portion of the principal balance of the discount mortgage loans. The mortgage loans which have a mortgage interest rate of less than 5.500% after deducting the master servicing fee rate and the applicable servicing fee rate are discount mortgage loans. Because the Class A-PO Certificates represent an interest solely in the discount mortgage loans, only principal payments, including prepayments of principal, and realized losses on the discount mortgage loans will affect the Class A-PO Certificates. The portion of the total principal balance of the mortgage loans not represented by the Class A-PO Certificates is the non-PO portion and is represented by the other Class A Certificates, referred to as the Class A Non-PO Certificates, and the Class B Certificates.

The relative interests in the initial non-PO portion of the principal balance of the mortgage loans represented by the Class A Non-PO Certificates and the Class B Certificates are subject to change over time because:

o certain unscheduled principal payments on the mortgage loans will be disproportionately allocated to the Class A Non-PO Certificates for a specified period; and

o certain losses and certain shortfalls on the mortgage loans will be allocated first to the classes of Class B Certificates in reverse numerical order prior to the allocation of such losses and shortfalls to the Class A Certificates, as discussed in "Description of the Certificates -- Distributions" and "-- Allocation of Losses" in this prospectus supplement.

Forms of Certificates; Denominations

Your certificates will be issued either in book-entry form or in fully registered, certificated form and in the minimum denomination and the incremental denomination set forth in the table beginning on page S-6. The offered certificates are not intended to be directly or indirectly held or beneficially owned by anyone in amounts lower than such minimum denominations.

MORTGAGE POOL

The assets of the trust are expected to consist of approximately [_____] mortgage loans with an aggregate unpaid principal balance as of the cut-off date of approximately $[_____]. The mortgage loans, which are the source of distributions to holders of the certificates, will consist of fixed interest rate, monthly pay, fully amortizing, one- to four-family, residential first mortgage loans substantially all of which have original terms to maturity of approximately 30 years.

See "Description of the Mortgage Loans" and "Appendix A" in this prospectus supplement.

Changes to Mortgage Pool

The depositor may remove mortgage loans from the pool, or may make substitutions for certain mortgage loans, in advance of the closing date.

After the issuance of the certificates, the depositor may purchase mortgage loans from the pool that have become delinquent or which are required to be transferred to the sponsor in order to permit the


S-10


sponsor to exercise rights which it may have against the originator of the mortgage loans. In addition, the depositor will be required to repurchase or, at its election, during the two year period following the closing date, substitute for, mortgage loans as a result of breaches of representations or warranties or as a result of defective documentation.

See "Description of the Mortgage Loans--Mandatory Repurchase or Substitution of Mortgage Loans" and "--Optional Purchase of Mortgage Loans" in this prospectus supplement.

Information regarding repurchases of the mortgage loans after the closing date will be available on the trust's monthly distribution reports on Form 10-D. See "Reports to Certificateholders" in the prospectus.

Optional Termination of the Trust

On any distribution date on which the aggregate scheduled principal balance of the mortgage loans is less than 10% of the aggregate unpaid principal balance of the mortgage loans as of the cut-off date, the depositor may, subject to certain conditions, purchase all outstanding mortgage loans in the mortgage pool and thereby effect early retirement of the certificates. See "The Pooling and Servicing Agreement--Termination; Optional Purchase of Mortgage Loans" in the prospectus.

DISTRIBUTIONS OF PRINCIPAL AND INTEREST TO CERTIFICATEHOLDERS

On each distribution date the amount available for distribution on the certificates, which consists of those payments, recoveries, advances and other receipts in respect of the mortgage loans which are available for distribution on such date, will be distributed generally in the following order of priority:

first, pro rata, to the Class A Certificates, in respect of interest which they are entitled to receive on such distribution date;

second, to the Class A Certificates in respect of principal which they are entitled to receive on such distribution date;

third, to the Class B Certificates in numerical order beginning with the Class B-1 Certificates in respect of interest and principal which they are entitled to receive on such distribution date; and

fourth, to the Class A-R Certificates, any remaining amounts.

However, if you are purchasing a class of accrual certificates, you will not receive interest distributions with respect to your certificates until either the principal balances of certain classes of accretion directed certificates have been reduced to zero as discussed under "Description of the Certificates--Interest" in this prospectus supplement or the principal balances of the Class B Certificates have been reduced to zero. Until then, interest which would otherwise be distributed on your class of accrual certificates will be added to the principal balance of such class of accrual certificates and will be distributed instead as principal to certain classes of accretion directed certificates and such class of accrual certificates as specified under "Description of the Certificates -- Principal (Including Prepayments)" in this prospectus supplement.

In addition, certain payments of principal to which the Class A-PO Certificates are entitled on a distribution date will only be paid out of amounts otherwise distributable as principal to the Class B Certificates on such distribution date. See "Description of the Certificates -- Principal (Including Prepayments)" in this prospectus supplement.

The amount available for distribution to certificateholders will not include amounts used to pay the servicing fee and the master servicing fee or amounts used to reimburse the expenses of certain transaction parties. Such fees will be paid on each distribution date from interest payments received on the mortgage loans prior to any distributions on the certificates. The servicing fee for each distribution date is equal to the product of (i) one-twelfth of [___]% and (ii) the aggregate scheduled principal balance of the mortgage loans as of the first day of the month of such distribution date. The master servicing fee for each distribution date is equal to the product of (i) one-twelfth of [___]% and (ii) the aggregate scheduled principal balance of the mortgage loans as of the first day of the month of such distribution date.

Interest Distributions

An interest-bearing class will accrue interest for each interest accrual period in an amount equal to:

o 1/12th of the pass-through rate for the class multiplied by the outstanding principal balance of such class on the related distribution date minus

o the amount of certain interest shortfalls arising from the timing of prepayments on the mortgage


S-11


loans and the application of the Servicemembers Civil Relief Act, as it may be amended from time to time, or comparable state legislation and interest losses allocated to the class as described under "Description of the Certificates -- Interest" in this prospectus supplement.

The allocation of interest distributions among the Class A Non-PO Certificates will be made as described under "Description of the Certificates -- Distributions" and "-- Interest" in this prospectus supplement.

Principal Distributions

The calculation of the amount of principal which each class of offered certificates is entitled to receive on each distribution date and the priority of principal distributions among the Class A Certificates are described under "Description of the Certificates--Distributions" and "-- Principal (Including Prepayments)" in this prospectus supplement.

Credit Enhancement

The rights of each class of Class B Certificates to receive distributions will be subordinated to the rights of the Class A Certificates to receive distributions and the classes of Class B Certificates, if any, with lower numerical designations to receive distributions.

In general, the protection afforded the more senior classes of certificates by means of this subordination of the more junior classes of certificates will be effected in two ways:

o by the preferential right of such more senior classes to receive, prior to any distribution being made on any distribution date to the more junior classes of certificates, the amounts of interest and principal due on the more senior classes of certificates, other than amounts payable to the Class A-PO Certificates, as a reimbursement for realized losses, and, if necessary, by the right of such more senior classes of certificates to receive future distributions on the mortgage loans that would otherwise have been allocated to the more junior classes of certificates; and

o by the allocation of losses resulting from the liquidation of defaulted mortgage loans or the bankruptcy of mortgagors to the more junior classes of certificates in inverse order of seniority, until their respective principal balances have been reduced to zero, prior to the allocation of such losses to the more senior classes of certificates.

Credit support for the Class A Certificates is provided by subordination of the Class B Certificates as follows:

Subordination of Subordinated Certificates

| Priority | Senior | | | of | (Credit Support | /|\ | | Payment | [___]%) | | | |-------------|------------------| | | | | | Class B-1 | | | | | | (Credit Support | | | | | | [___]%) | | | | | |------------------| | | | | | Class B-2 | | | | | | (Credit Support | | | | | | [___]%) | | | | | |------------------| | | | | | Class B-3 | | | | | | (Credit Support | | | | | | [___]%) | | | | | |------------------| | | | | | Class B-4 | | | | | | (Credit Support | | | | | | [___]%) | | | | | |------------------| | | | | | Class B-5 | | | | | | (Credit Support | | | | | | [___]%) | | | | | |------------------|-------------| | | | Class B-6 | Order | | \|/ | (Credit Support | of Loss | | | 0.00%) | Allocation |

The approximate initial credit support percentages set forth in the preceding chart show the initial principal balance of the class or classes of certificates subordinate to a class or classes as a percentage of the aggregate unpaid principal balance of the mortgage loans as of the cut-off date.

In addition, in order to increase the period during which the principal balances of the Class B Certificates remain available as credit enhancement to the Class A Certificates, a disproportionate amount of prepayments and unscheduled principal receipts with respect to the mortgage loans will be allocated to the Class A Non-PO Certificates in the aggregate. This allocation will accelerate the amortization of the Class A Non-PO Certificates while, in the absence of losses due to the liquidation of defaulted mortgage loans or losses resulting from the bankruptcy of mortgagors, increasing the percentage interest in the principal balance of the mortgage loans evidenced by the Class B Certificates. This disproportionate allocation of prepayments and unscheduled principal receipts will "step down" over time unless specified delinquency and loss tests are not met. See "Description of the Certificates--Principal (Including Prepayments)--Calculation of Amount to be


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Distributed on the Certificates" and "Prepayment and Yield Considerations" in this prospectus supplement.

After the principal balances of the Class B Certificates have been reduced to zero, the principal portion of all losses, other than the portion attributable to the discount mortgage loans, will be allocated to the Class A Non-PO Certificates. To the extent such losses arise with respect to discount mortgage loans, principal losses will be shared between the Class A Non-PO Certificates and the Class A-PO Certificates according to their respective interests in such mortgage loans. The principal portion of any losses borne by the Class A Non-PO Certificates will be shared pro rata by such classes of Class A Non-PO Certificates based on their then-outstanding principal balances (or, in the case of a class of accrual certificates, such class' initial principal balance, if lower) and the interest portion of such losses will be shared pro rata by the Class A Non-PO Certificates based on interest accrued. However, the share of principal losses allocated to a class of super senior certificates will be borne by the related class of super senior support certificates, together with such class of super senior support certificates' own share of losses. To this extent, a class of super senior support certificates is subordinate to its related class of super senior certificates. See "Description of the Certificates--Subordination of Class B Certificates" and "--Allocation of Losses" in this prospectus supplement.

If you are purchasing the Class B Certificates, you should be aware that losses will be allocated to your certificates before being borne by the Class A Non-PO Certificates.

See "Description of the Certificates--Distributions," "--Subordination of Class B Certificates" and "--Allocation of Losses" in this prospectus supplement.

EFFECTS OF PREPAYMENTS ON YOUR INVESTMENT EXPECTATIONS

The rate of prepayments on the mortgage loans will affect the investment performance of the offered certificates.

The Class A and Class B Certificates were structured assuming, among other things, that prepayments on the mortgage loans occur at a constant rate of
[_____]% of the standard prepayment assumption as described in this prospectus supplement under "Prepayment and Yield Considerations." However, no one can predict the actual rate of prepayment of principal on the mortgage loans.

In deciding whether to purchase any offered certificates, you should make an independent decision as to the appropriate prepayment assumptions to use. If prepayments on the applicable mortgage loans are higher or lower than you anticipate, the investment performance of the offered certificates may vary materially and adversely from your investment expectations.

Factors affecting the rate of prepayment on the mortgage loans and the manner in which prepayments are allocated among the classes of certificates are discussed in this prospectus supplement under "Description of the Certificates -- Principal (Including Prepayments)" and "Prepayment and Yield Considerations."

The actual yield on your certificates may not be equal to the yield you anticipated at the time of purchase. In addition, even if the actual yield is equal to the yield you anticipated at the time of purchase, the total return on investment you expected or the expected weighted average life of your certificates may not be realized. These effects are summarized below.

Yield

The actual yield on your certificates depends on the:

o pass-through rate, if any;

o price paid;

o absence or occurrence of interest shortfalls or losses;

o absence or occurrence of principal losses; and

o rate and timing of principal prepayments.

If you purchase offered certificates, your yield, absent shortfalls or losses, will primarily be a function of the price paid and the rate and timing of prepayments on the applicable mortgage loans.

o If you purchase your certificate at an amount equal to its unpaid principal balance -- that is, at "par"-- your effective yield will approximate the pass-through rate on that certificate.

o If you pay less or more than the unpaid principal balance of your certificate -- that is, buy the certificate at a "discount" or "premium," respectively -- then your effective yield will be higher or lower, respectively, than the pass-through rate on the certificate, because such


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discount or premium will be amortized over the life of the certificate.

o Any deviation in the actual rate of prepayments on the applicable mortgage loans from the rate you assumed will affect the period of time over which, or the rate at which, any discount or premium will be amortized and, consequently, will cause your actual yield to differ from that which you anticipated.

If you purchase principal only certificates, your yield, absent losses, will primarily be a function of the price you paid for your certificates and the rate and timing of principal payments on the discount mortgage loans.

In addition, the inverse floating rate certificates are highly sensitive to LIBOR and increases in LIBOR will have a negative effect on the yield to maturity of your certificates.

The particular sensitivities of the principal only and inverse floating rate certificates to prepayments and, in the case of the inverse floating rate certificates, to LIBOR are separately displayed in the tables appearing in Appendix D.

The yield to maturity of classes subordinated to other classes will be more sensitive to losses due to liquidations of the mortgage loans and the timing thereof than the classes to which they are subordinated.

If you are purchasing a class of super senior support certificates, which is subordinate to the related class of super senior certificates after the Class B Certificates are no longer outstanding, you should consider the effect of this increased sensitivity to losses on your yield to maturity.

The sensitivities of the yields to maturity of the Class B-2 and Class B-3 Certificates to losses are illustrated in the tables appearing in Appendix E. These illustrations are based on default, loss and other assumptions which are unlikely to match actual experience on the mortgage loans; therefore, your results will vary.

If you are purchasing offered certificates at a discount, particularly the principal only certificates, you should consider the risk that a slower than anticipated rate of principal payments on the applicable mortgage loans will have a negative effect on the yield to maturity of your certificates.

If you are purchasing offered certificates at a premium, you should consider the risk that a faster than anticipated rate of principal payments on the mortgage loans will have a negative effect on the yield to maturity of your certificates and that a rapid rate of principal payments on the mortgage loans could result in the loss of all or part of your initial investment.

Reinvestment Risk

As stated above, if you purchase an offered certificate at par, fluctuations in the rate of distributions of principal will generally not affect your yield to maturity. However, the total return on your investment, even if you purchase your certificates at par, will be reduced if principal distributions received on your certificates cannot be reinvested at a rate as high as the stated pass-through rate or, in the case of principal only certificates, the expected yield.

You should consider the risk that rapid rates of prepayments on the mortgage loans may coincide with periods of low prevailing market interest rates. During periods of low prevailing market interest rates, mortgagors may be expected to prepay or refinance mortgage loans that carry interest rates significantly higher than then-current interest rates for mortgage loans. Consequently, the amount of principal distributions available to you for reinvestment at such low prevailing interest rates may be relatively large.

Conversely, slow rates of prepayments on the mortgage loans may coincide with periods of high prevailing market interest rates. During such periods, it is less likely that mortgagors will elect to prepay or refinance mortgage loans and, therefore, the amount of principal distributions available to you for reinvestment at such high prevailing interest rates may be relatively small.

Weighted Average Life Volatility

One indication of the impact of varying prepayment speeds on a security is the change in its weighted average life.

o The "weighted average life" of a class of offered certificates is the average amount of time that will elapse between the date of issuance of the class and the date on which each dollar in reduction of the principal balance of the class is distributed to the investors.


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Low rates of prepayment on the applicable mortgage loans may result in the extension of the weighted average life of a certificate. High rates of prepayment may result in the shortening of the weighted average life of a certificate.

In general, if you purchase your certificates at par and the weighted average life of your certificates is extended beyond your anticipated time period, the market value of your certificates may be adversely affected even though the yield to maturity on your certificates is unaffected.

Because on any distribution date companion certificates will not receive principal distributions until the PAC Certificates have been paid to their planned balances, and will receive all principal distributions in excess of those required to pay the PAC Certificates to their planned balances, the weighted average life of a companion certificate is particularly sensitive to principal prepayments on the mortgage loans.

See "Prepayment and Yield Considerations" in this prospectus supplement.

The sensitivities of the weighted average lives of the offered certificates to prepayments are illustrated in the tables appearing in Appendix C. These illustrations are based on prepayment and other assumptions which are unlikely to match the actual experience on the mortgage loans. Therefore, your results will vary.

See "Risk Factors -- Prepayments May Adversely Affect Yield" and "-- Interest Only Mortgage Loans May Have Higher Risk of Default or Rates of Prepayment," "Prepayment and Yield Considerations" and "Description of the Certificates -- Principal (Including Prepayments) -- Principal Payment Characteristics of the PAC Certificates and the Companion Certificates" in this prospectus supplement.

FEDERAL INCOME TAX STATUS

For federal income tax purposes, the trust estate will be treated as a REMIC.

o The offered certificates (other than the Class A-R Certificates) and the Class B-4, Class B-5 and Class B-6 Certificates will constitute "regular interests" in the REMIC and will be treated as newly-originated debt instruments for most federal income tax purposes.

o The Class A-R Certificates are residual certificates. The Class A-R Certificates will be the sole "residual interest" in the REMIC.

You must report income received on your certificates as it accrues from distribution date to distribution date, even if it is before such income is distributed in cash to you.

Certain classes of certificates may be issued with "original issue discount." If your class of certificates is issued with original issue discount, you must report original issue discount income over the life of your certificate, often well before such income is distributed in cash to you. See "Federal Income Tax Considerations" in this prospectus supplement.

The residual certificates will not be treated as debt instruments for federal income tax purposes. Instead, if you are a holder of a residual certificate, you must include the taxable income or loss of the REMIC in determining your federal taxable income. You may have to use funds other than distributions on your certificate to meet the tax liabilities resulting from the ownership of a residual certificate.

In addition, certain transfers of the residual certificates may be disregarded for federal tax purposes, with the transferor continuing to have tax liabilities for the transferred certificates. See "Description of the Certificates -- Restrictions on Transfer of the Residual Certificates" and "Federal Income Tax Considerations" in this prospectus supplement and "Material Federal Income Tax Consequences -- Federal Income Tax Consequences for REMIC Certificates" in the prospectus.

ERISA CONSIDERATIONS

If you are a fiduciary of a retirement plan or other employee benefit plan or arrangement subject to ERISA, the Internal Revenue Code or any federal, state or local law which is, to a material extent, similar to ERISA or the Internal Revenue Code, you should carefully review with your legal advisors whether the purchase or holding of offered certificates could give rise to a transaction prohibited or not otherwise permissible under the rules or regulations referred to above.

The residual certificates may not be purchased by or transferred to a plan or a person acting on behalf of or investing the assets of a plan. See "Description of the Certificates -- Restrictions on Transfer of the Residual Certificates" and "ERISA Considerations" in this prospectus supplement.


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LEGAL INVESTMENT

o The Class A and Class B-1 Certificates will constitute "mortgage related securities" for purposes of the Secondary Mortgage Market Enhancement Act of 1984 as amended, so long as they are rated in one of the two highest rating categories by at least one nationally recognized statistical rating organization.

o The Class B-2 and Class B-3 Certificates will not constitute "mortgage related securities" under this act.

Prospective purchasers, particularly those whose investment activities are subject to legal investment laws and regulations, regulatory capital requirements or review by regulatory authorities, may be subject to restrictions on investment in the offered certificates and should consult their own legal, tax, financial and accounting advisors in determining the suitability of and consequences to them of the purchase, ownership and disposition of the offered certificates.

See "Legal Investment" in the prospectus.

PERIODIC REPORTS

The master servicer will file periodic reports with the SEC on behalf of the issuing entity under the name ["Wells Fargo Alternative Loan 20 - Trust" [(File No. 333- - )]].

See "Where You Can Find More Information" in the prospectus.


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RISK FACTORS

You should consider carefully in connection with the purchase of the offered certificates, the following factors, as well as those described under "Risk Factors" in the prospectus.

"Alternative A" Mortgage Loans May Experience Greater Rates of Delinquency and Foreclosure Due to Underwriting Standards

Approximately [_____]% of the mortgage loans (by aggregate unpaid principal balance as of the cut-off date) were generally originated in conformity with the sponsor's "Alternative A" underwriting standards or the "Alternative A" underwriting standards of certain third party originators. See "The Mortgage Loans--Mortgage Loan Underwriting" herein. Certain of these mortgage loans may not meet the sponsor's general underwriting policies for "prime" mortgage loans due to borrower credit characteristics. In addition, the sponsor's "Alternative A" underwriting program permits less restrictive underwriting criteria as compared to the sponsor's general underwriting criteria, including additional types of mortgaged properties, categories of borrowers and/or reduced documentation requirements. In particular, a portion of the mortgage loans are stated loans, for which no verification of income was required and in some instances, no verification of assets was required. As a consequence, delinquencies, foreclosures and cumulative losses may be expected to be greater with respect to these mortgage loans than with respect to mortgage loans originated in conformity with the sponsor's general underwriting standards. The documentation levels for the mortgage loans are identified in Appendix A. See "Risk Factors--Mortgage Loans May Experience Greater Rates of Delinquency and Foreclosure Due to Underwriting Standards" in the prospectus.

Decline in Residential Real Estate Values May Increase Risk of Loss and Adversely Affect Your Investment

In recent months, delinquencies and losses with respect to residential mortgage loans generally have increased and may continue to increase. In addition, in recent months the value of mortgaged properties in many states have declined or remained stable, after extended periods of appreciation. If residential real estate values generally or in a particular geographic area decline or fail to increase, the loan-to-value ratios shown in the tables appearing in Appendix A might not be a reliable indicator of the rates of delinquencies, foreclosures and losses that could occur on the mortgage loans. A continued decline or lack of increase in property values where the outstanding balances of the mortgage loans and any secondary financing on the related mortgaged properties are close to or exceed the value of the mortgaged properties may result in delinquencies, foreclosures and losses that are higher than you anticipated or those in the sponsor's prior securitizations involving the depositor.

In addition, adverse economic conditions and other factors (which may or may not affect real property values) may affect the mortgagors' timely payment of scheduled payments of principal and interest on the mortgage loans and, accordingly, the actual rates of delinquencies, foreclosures and losses with respect to any mortgage pool. These other factors could include excessive building resulting in an oversupply of housing in a particular area or a decrease in employment reducing the demand for housing in an area or zoning or environmental restrictions preventing additions to the housing supply in an area. To the extent that credit enhancements do not cover such losses, the yield on the offered certificates may be adversely impacted.

Mortgage Securities Market Illiquidity May Adversely Affect the Value of Your Certificates

Recently, the mortgage backed securities market has experienced reduced liquidity which has resulted primarily from investor concerns arising from increased delinquencies and foreclosures on mortgage loans, particularly subprime and "Alternative A" mortgage loans, and the failure of several subprime and "Alternative A" mortgage lenders. Accordingly, it is possible that for some period of time investors who desire to sell their certificates in the secondary market may find fewer potential purchasers and experience lower resale prices than under "normal" market conditions. See "Risk Factors--Limited Liquidity for Certificates" in the prospectus.

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Prepayments May Adversely Affect Yield

The rate of distributions of principal and the yield to maturity on your certificates will be directly related to the rate of payments of principal on the applicable mortgage loans and the amount and timing of mortgagor defaults resulting in realized losses. Mortgagors are permitted to prepay the mortgage loans, in whole or in part, at any time without penalty. The principal payments on the mortgage loans may be in the form of scheduled principal payments or principal prepayments (for this purpose, the term "principal prepayment" includes prepayments and any other recovery of principal in advance of the scheduled due date, including repurchases and liquidations due to default, casualty, condemnation and similar events). Any of these prepayments will result in distributions to you of amounts that would otherwise be distributed over the remaining term of the mortgage loans.

The rate of principal payments on the mortgage loans will be affected by, among other things:

o the amortization schedules of the mortgage loans;

o the rate of principal prepayments (including partial prepayments and those resulting from refinancing) thereon by mortgagors;

o liquidations of defaulted mortgage loans;

o repurchases of mortgage loans by the depositor as a result of defective documentation or breaches of representations and warranties;

o optional purchases by the depositor of defaulted mortgage loans;

o the optional purchase by the depositor of all of the mortgage loans in connection with the termination of the trust estate; and

o general and targeted solicitations for refinancing by mortgage originators (including the sponsor).

The rate of payments (including prepayments) on pools of mortgage loans is influenced by a variety of economic, geographic and social factors and will depend greatly on the level of mortgage interest rates:

o If prevailing rates for similar mortgage loans fall below the mortgage interest rates on the mortgage loans, the rate of prepayment would generally be expected to increase.

o Conversely, if interest rates on similar mortgage loans rise above the mortgage interest rates on the mortgage loans, the rate of prepayment would generally be expected to decrease.

If you are purchasing offered certificates at a discount, particularly the Class A-PO Certificates, you should consider the risk that if principal payments on the mortgage loans, or, in the case of the Class A-PO Certificates, on the discount mortgage loans, occur at a rate slower than you expected, there will be a negative effect on the yield to maturity of your certificates.

If you are purchasing offered certificates at a premium, you should consider the risk that if principal payments on the mortgage loans occur at a rate faster than you expected, there will be a negative effect on the yield to maturity of your certificates.

The particular sensitivity of the principal only certificates is separately displayed in the table appearing in Appendix D.

You must make your own decisions as to the appropriate prepayment assumptions to be used in deciding whether to purchase offered certificates.

As described in this prospectus supplement under "Description of the Certificates--Principal (Including Prepayments)," the Class A Prepayment Percentage of all principal prepayments (excluding for this purpose, partial liquidations due to default, casualty, condemnation and similar events) initially will be distributed to the classes of Class A Certificates that are entitled to receive principal prepayment distributions at that time. This may result in all

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(or a disproportionate percentage) of those principal prepayments being distributed to the Class A Certificates and none (or less than their pro rata share) of those principal prepayments being distributed to holders of the subordinated certificates during the periods of time described in the definition of "Class A Prepayment Percentage."

The timing of changes in the rate of prepayments may significantly affect the actual yield to you, even if the average rate of principal prepayments is consistent with your expectations. In general, the earlier the payment of principal of the mortgage loans, the greater the effect on your yield to maturity for certificates purchased at a price other than par.

Geographic Concentration May Increase Risk of Loss Because of Adverse Economic Conditions or Natural Disasters

The yield to maturity on your certificates may be affected by the geographic concentration of the mortgaged properties securing the mortgage loans. Certain regions of the United States from time to time will experience weaker regional economic conditions and housing markets and, consequently, will experience higher rates of loss and delinquency than on mortgage loans generally. Any concentration of the mortgage loans in such a region may present risk considerations in addition to those generally present for similar mortgage-backed securities without such concentration. In addition, certain regions have experienced or may experience natural disasters, including earthquakes, fires, floods, hurricanes and tornadoes, which may adversely affect property values. Although mortgaged properties located in certain identified flood zones will be required to be covered by flood insurance, for the minimum amount required by the sponsor, such amount may be significantly smaller than the unpaid principal balance of the related mortgage loan. In addition, no mortgaged properties will otherwise be required to be insured against earthquake damage. The following states have concentrations of mortgaged properties in excess of 10% (by the aggregate unpaid principal balance as of the cut-off date) of the mortgage pool: [State] and [State].

Any deterioration in housing prices in the regions in which there is a significant concentration of mortgaged properties, as well as the other regions in which the mortgaged properties are located, and any deterioration of economic conditions in such regions which adversely affects the ability of borrowers to make payments on the mortgage loans may increase the likelihood of losses on the mortgage loans. Such losses, if they occur, may have an adverse effect on the yield to maturity of your certificates, especially if they are subordinated and particularly if they are Class B-3 Certificates.

The concentrations of mortgaged properties by state and geographic areas are identified in Appendix A.

High Balance Loans May Increase Risk of Loss on Certificates

Mortgage loans with large balances relative to the principal balances of the classes of Class B Certificates may, in the event of liquidation, result in realized losses large enough to significantly reduce or eliminate the principal balance of one or more of such classes. In the event such mortgage loans are discount mortgage loans, a realized loss may have a similar impact on the Class A-PO Certificates.

In addition, any realized loss that reduces the principal balances of the Class B Certificates decreases the subordination provided to the Class A Certificates and increases the risk that the Class A Non-PO Certificates will have to bear realized losses in the future and the Class A-PO Certificates will not be reimbursed for principal losses.

The original principal balances of the mortgage loans and the percentage they represent of the trust estate are specified in Appendix A.

Lack of income or asset verification may increase risk of loss

Certain of the mortgage loans were underwritten under reduced documentation programs referred to as the "stated income, stated assets," "stated income, verified assets" and "verified income, stated assets" documentation programs. The "stated income, stated assets" documentation program permits the mortgagor to be qualified on the basis of his or her monthly income and assets as stated on the loan application, without independent verification. The "stated income, verified assets" and "verified income, stated assets" documentation programs permit the mortgagor to be qualified on the basis of his or her income or assets, as applicable, as stated on the loan application, in each case without independent verification. When the borrower chooses a reduced documentation program

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instead of providing full documentation, it may increase the possibility that, due to mortgagor error or fraud, the amount of credit extended exceeds the mortgagor's capacity to pay, particularly with respect to interest only mortgage loans, on which the payments will increase during the term of the mortgage loan.

Under the pooling and servicing agreement, the depositor will represent that there is no fraud by the mortgagor in the origination of a mortgage loan, however, this representation does not cover information regarding income or assets as stated on the loan application. Therefore, the depositor will not have any repurchase or substitution obligation as a result of mortgagor fraud regarding income or assets stated on a loan application. As a consequence, the rate of delinquencies and losses may be higher on such mortgage loans than on mortgage loans under which the mortgagor's income and/or assets has been verified.

See "Description of the Mortgage Loans--Mortgage Loan Data Appearing in Appendix A" herein and Appendix A to this prospectus supplement for information regarding the mortgage loans underwritten under the "stated income, stated assets," "stated income, verified assets" and "verified income, stated assets" documentation programs.

Delinquencies and Losses on the Mortgage Loans Will Adversely Affect Your Yield

Delinquencies on the mortgage loans which are not advanced by the servicer (because the servicer has determined that these amounts, if advanced, would be nonrecoverable), will adversely affect the yield on the certificates. The servicer will determine that a proposed advance is nonrecoverable when, in the good faith exercise of its servicing judgment, it believes the proposed advance would not be ultimately recoverable from the related mortgagor, related liquidation proceeds, or other recoveries in respect of the mortgage loan. The servicer will be entitled to recover from amounts on deposit in the certificate account any advances previously made which it subsequently determines to be nonrecoverable prior to any distribution on the certificates. Because of the priority of distributions, shortfalls resulting from delinquencies that are not covered by advances or from the reimbursement of advances which the servicer determines to be nonrecoverable will be borne first by the subordinated certificates (in reverse numerical order), and then by the senior certificates.

Net interest shortfalls will adversely affect the yields on the offered certificates. In addition, losses generally will be borne by the subordinated certificates, as described in this prospectus supplement under "Description of the Certificates -- Allocation of Losses." As a result, the yields on the offered certificates will depend on the rate and timing of realized losses on the mortgage loans.

Subordination of Super Senior Support Certificates and the Class B Certificates Increases Risk of Loss

If you purchase a class of super senior support certificates, you should consider the risk that on or after the date on which the aggregate principal balance of the Class B Certificates has been reduced to zero, the principal portion of realized losses allocated to the related class of super senior certificates will be borne by your class of super senior support certificates (in addition to the principal portion of realized losses allocated to your class of super senior support certificates) and not by the related class of super senior certificates so long as the principal balance of your class of super senior support certificates remains outstanding. See "Description of the Certificates -- Allocation of Losses" herein.

The rights of the holders of each class of Class B Certificates to receive distributions will be subordinated to such rights of the holders of the Class A Certificates and the holders of the lower-numbered classes of Class B Certificates, if any. The rights of the holders of each class of Class B Certificates to receive distributions will be subordinated to such rights of the holders of the Class A Certificates and the holders of the lower-numbered classes of Class B Certificates, if any. In addition, the applicable non-PO portion of the principal portion of any realized loss on the mortgage loans will be allocated to the Class B Certificates in the reverse order in which they are entitled to distributions of principal before being allocated to the Class A Non-PO Certificates. Accordingly, if you are purchasing the Class B Certificates, you will be more likely to experience losses as a result of the occurrence of losses or interest shortfalls on the mortgage loans. See "Description of the Certificates -- Subordination of Class B Certificates" herein.

In addition, the Class A-PO Certificates will be entitled to reimbursement for principal losses from amounts otherwise distributable as principal on the Class B Certificates, in reverse numerical order.

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Interest Only Mortgage Loans May Have Higher Risk of Default or Rates of Prepayment

Approximately [___]% (by aggregate unpaid principal balance as of the cut-off date) of the mortgage loans are interest only mortgage loans, which require only the payment of interest with respect to, at the borrower's election at the time of origination of the mortgage loan, the first three to fifteen years of payments with respect to the mortgage loan. At that time, the payments on each such mortgage loan will be recalculated to fully amortize its unpaid principal balance over the remaining life of such mortgage loan and the mortgagor will be required to make payments of both principal and interest. The required payment of principal will increase the burden on the mortgagor and may increase the risk of default under such mortgage loan. In underwriting an interest only loan, the ability of the mortgagor to make payments in respect of principal is not considered. The increase in the mortgagor's monthly payment attributable to principal will occur when the mortgagor's monthly payment may also be increasing as a result of an increase in the mortgage interest rate on the related adjustment date. This increase in monthly payment may significantly increase the risk of default under such mortgage loan. In addition, the increase in the monthly payment to be made by a mortgagor may induce the mortgagor to refinance such mortgage loan which would result in a prepayment of such loan.

The Rate of Default on Mortgage Loans that are Secured by Investor Properties May be Higher than on Other Mortgage Loans

Approximately [___]% (by aggregate unpaid principal balance as of the cut-off date) of the mortgage loans in the mortgage pool are expected to be secured by investor properties. An investor property is a property which, at the time of origination, the mortgagor represented would not be used as the mortgagor's primary residence or second home. Because the mortgagor is not living on the property, the mortgagor may be more likely to default on the mortgage loan than on a comparable mortgage loan secured by a primary residence, or to a lesser extent, a second home. In addition, income expected to be generated from an investor property may have been considered for underwriting purposes in addition to the income of the mortgagor from other sources. Should this income not materialize, it is possible the mortgagor would not have sufficient resources to make payments on the mortgage loan.

FICO Scores May Not Accurately Predict the Likelihood of Default

The sponsor generally uses FICO scores as part of its underwriting process. The tables in Appendix A show FICO scores for the mortgagors obtained either at the time of origination of their mortgage loans or more recently. A FICO score purports only to be a measurement of the relative degree of risk a borrower represents to a lender, i.e., that a borrower with a higher score is statistically expected to be less likely to default in payment than a borrower with a lower score. In addition, it should be noted that FICO scores were developed to indicate a level of default probability over a two-year period, which does not correspond to the expected life of a mortgage loan. Furthermore, FICO scores were not developed specifically for use in connection with mortgage loans, but for consumer loans in general. Therefore, FICO scores do not take into consideration the effect of mortgage loan characteristics on the probability of repayment by the borrower. Neither the depositor nor the sponsor makes any representations or warranties as to any borrower's current FICO score, the actual performance of any mortgage loan or that a particular FICO score should be relied upon as a basis for an expectation that a borrower will repay its mortgage loan according to its terms.

Decrement and Sensitivity Tables are Based Upon Assumptions and Models

The decrement tables set forth in Appendix C and the sensitivity tables set forth in Appendix E have been prepared on the basis of the structuring assumptions described under "Prepayment and Yield Considerations" and the characteristics of the assumed mortgage loans set forth in the table appearing in Appendix B. There will likely be discrepancies between the characteristics of the actual mortgage loans included and the characteristics of the assumed mortgage loans used in preparing the decrement tables and the sensitivity tables. Any such discrepancy may have an effect upon the percentages of initial principal balances outstanding set forth in the decrement tables (and the weighted average lives of the offered certificates) and the yields to maturity set forth in the sensitivity tables. In addition, to the extent that the mortgage loans that actually are included have characteristics that differ from those assumed in preparing the decrement tables and the sensitivity tables, the principal balance of a class of offered certificates could be reduced to zero earlier or later than indicated by the decrement tables and the yield to maturity may be higher or lower than indicated in the sensitivity tables.

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The models used in this prospectus supplement for prepayments and defaults also do not purport to be a historical description of prepayment or default experience or a prediction of the anticipated rate of prepayment or default of any pool of mortgage loans, including the mortgage loans contained in the trust. It is highly unlikely that the mortgage loans will prepay or liquidate at any of the rates specified or that losses will be incurred according to one particular pattern. The assumed percentages of SDA and SPA and the loss severity percentages shown in the Appendices are for illustrative purposes only. For a description of SDA and SPA, see "Prepayment and Yield Considerations" in this prospectus supplement. The actual rates of prepayment and liquidation and loss severity experience of the mortgage loans may not correspond to any of the assumptions made in this prospectus supplement. For these reasons, the weighted average lives of the offered certificates may differ from the weighted average lives shown in the tables in Appendix C. Further, because the timing of cash flows is critical to determining yield, the pre-tax yields to maturity of the Class B-2 and Class B-3 Certificates are likely to differ from the pre-tax yields to maturity shown in the tables in Appendix E.

Residual Certificates May Have Adverse Tax Consequences

The residual certificates will be the sole "residual interest" in the REMIC for federal income tax purposes. Holders of the residual certificates must report as ordinary income or loss the net income or the net loss of the REMIC whether or not any cash distributions are made to them. This allocation of income or loss may result in a zero or negative after-tax return. No cash distributions are expected to be made with respect to the residual certificates other than the distribution of their principal balance and interest on that balance. Due to their tax consequences, the residual certificates will be subject to restrictions on transfer that may affect their liquidity. In addition, the residual certificates may not be acquired by ERISA plans or similar governmental plans.

United States Military Operations May Increase Risk of Relief Act Shortfalls

As a result of military operations in Afghanistan and Iraq, the United States has placed a substantial number of armed forces reservists and members of the National Guard on active duty status. It is possible that the number of reservists and members of the National Guard placed on active duty status may remain at high levels for an extended time. To the extent that a member of the military, or a member of the armed forces reserves or National Guard who is called to active duty, is a mortgagor of a mortgage loan in the trust, the interest rate limitation of the Servicemembers Civil Relief Act, as it may be amended from time to time, or any comparable state legislation will apply. This may result in interest shortfalls on the mortgage loans, which will be borne by all interest-bearing classes of certificates, as described herein under "Description of the Certificates -- Interest." The depositor has not taken any action to determine whether any of the mortgage loans would be affected by such interest rate limitation. See "Description of the Certificates -- Interest" herein and "Certain Legal Aspects of the Mortgage Loans -- Servicemembers Civil Relief Act and Similar Laws" in the prospectus.

Proposed Bankruptcy Amendments May Delay or Reduce Collections on Mortgage Loans

Various amendments to the United States Bankruptcy Code have been proposed in the United States Senate and House of Representatives that would, if adopted, give bankruptcy courts increased power to modify the terms of a mortgage loan secured by the borrower's principal residence after the borrower files for relief under Chapter 13 of the Bankruptcy Code. These proposed amendments would allow a court to, among other things, reduce the principal balance of the mortgage loan that is treated as secured (treating the remainder as unsecured), extend the loan's final maturity date, reduce the loan's interest rate and delay the effective date of an adjustable rate increase. In addition, one such proposed amendment would allow a court to treat certain of the borrower's prior payments of interest on the mortgage loan as voidable transfers if the court found a substantial failure by the lender to disclose material terms regarding such interest. The depositor is unable to predict whether or when any of the proposals may be enacted into law or whether the scope of the proposals may be narrowed or expanded in the legislative process. However, if adopted, any of the actions taken by a bankruptcy court, as set forth above, could delay distributions, reduce the yield or result in losses on your certificates.

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FORWARD LOOKING STATEMENTS

This prospectus supplement and the accompanying prospectus contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended. Such forward-looking statements, together with related qualifying language and assumptions, are found in the material, including each of the tables, set forth under "Risk Factors" and "Prepayment and Yield Considerations" and in the Appendices. Forward-looking statements are also found elsewhere in this prospectus supplement and the prospectus, and may be identified by, among other things, accompanying language including the words "expects," "intends," "anticipates," "estimates" or analogous expressions, or by qualifying language or assumptions. Such statements involve known and unknown risks, uncertainties and other important factors that could cause the actual results or performance to differ materially from such forward-looking statements. Such risks, uncertainties and other factors include, among others, general economic and business conditions, competition, changes in political, social and economic conditions, regulatory initiatives and compliance with government regulations, customer preference and various other matters, many of which are beyond the Depositor's control. These forward-looking statements speak only as of the date of this prospectus supplement. The Depositor expressly disclaims any obligation or undertaking to disseminate any updates or revisions to such forward-looking statements to reflect any change in the Depositor's expectations with regard thereto or any change in events, conditions or circumstances on which any forward-looking statement is based.

THE SPONSOR

The Sponsor, Wells Fargo Bank, N.A. ("Wells Fargo Bank") is an indirect, wholly-owned subsidiary of Wells Fargo & Company.

See "The Sponsor," "The Sponsor's Mortgage Loan Programs," "Servicing of the Mortgage Loans" and "The Pooling and Servicing Agreement" in the prospectus for more information about the Sponsor, its securitization programs, underwriting criteria and procedures used to originate the Mortgage Loans and its material roles and duties in this securitization.

STATIC POOL INFORMATION

Information concerning the Sponsor's prior residential mortgage loan securitizations involving Alt-A Fixed-Rate Loans is available on the internet at http://www.securitieslink.com/staticpools.

Without charge or registration, by clicking on the link in the row titled "WFALT 200 - ," investors can view on this website the following information:

o summary information regarding original characteristics of the Sponsor's prior securitized pools of Alt-A Fixed-Rate Loans; and

o delinquency, cumulative loss and prepayment information for the five years preceding the date of first use of this prospectus supplement regarding the Sponsor's prior securitized pools of Alt-A Fixed-Rate Loans.

In the event any changes or updates are made to the information available on the Sponsor's website, the Depositor will provide a copy of the original information upon request to any person who writes or calls the Depositor at 8480 Stagecoach Circle, Frederick, Maryland 21701 Attention: Vice President, Structured Finance, telephone number (240) 586-5999.

The static pool reports available on the Sponsor's website relating to any of the Sponsor's prior securitized pools issued prior to January 1, 2006 are not deemed to be part of this prospectus supplement, the accompanying prospectus or the Depositor's registration statement.

Static pool performance may have been affected by various factors relating to the underlying borrower's personal circumstances, including, but not limited to, unemployment or change in employment (or in the case of

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self-employed mortgagors or mortgagors relying on commission income, fluctuations in income), marital separation and the mortgagor's equity in the related mortgaged property. In addition, static pool performance may be sensitive to adverse economic conditions, either nationally or regionally, may exhibit seasonal variations and may be influenced by the level of housing prices, the level of interest rates and changes in mortgage loan product features. In addition, changes over time in servicing practices or variations in mortgage loan underwriting guidelines or the application of such guidelines may affect the static pool performance. See "The Sponsor's Mortgage Loan Programs--Mortgage Loan Underwriting" in the prospectus. Regional economic conditions (including declining real estate values) may particularly affect delinquency and cumulative loss experience on mortgage loans to the extent that mortgaged properties are concentrated in certain geographic areas. The historical pool performance information contained in the static pool reports may be attributable to factors such as those described above, although there can be no assurance as to whether this information is the result of any particular factor or a combination of factors. Due to all of these factors, the Sponsor's static pool performance data may not be indicative of the future performance of the Mortgage Loans.

For additional information concerning the static pool information available on the website set forth above, see "Static Pool Information" in the prospectus.

THE DEPOSITOR

Wells Fargo Asset Securities Corporation (the "Depositor") is a direct, wholly owned subsidiary of Wells Fargo Bank and an indirect, wholly owned subsidiary of Wells Fargo & Company. The Depositor was incorporated in the State of Delaware on March 28, 1996 as Norwest Asset Securities Corporation. On April 7, 2000, Norwest Integrated Structured Assets, Inc., an affiliate of the Depositor, was merged into and with the Depositor. On April 17, 2000, the Depositor changed its name from Norwest Asset Securities Corporation to Wells Fargo Asset Securities Corporation.

The limited purposes of the Depositor are, in general, to acquire, own and sell mortgage loans; to issue, acquire, own, hold and sell mortgage pass-through securities and home equity asset-backed pass-through securities which represent ownership interests in mortgage loans, collections thereon and related properties; and to engage in any acts which are incidental to, or necessary, suitable or convenient to accomplish, the foregoing.

The Depositor will have limited obligations and rights under the Pooling and Servicing Agreement after the Closing Date, including, but not limited to, repurchasing or substituting Mortgage Loans due to breaches of representations and warranties or as a result of defective documentation, repurchasing at its option certain Mortgage Loans that have become delinquent, repurchasing Mortgage Loans that are required to be transferred to the Sponsor in order to permit the Sponsor to exercise rights that it may have against the originator of the Mortgage Loans or, in the circumstances described in the prospectus under "The Pooling and Servicing Agreement--Termination; Optional Purchase of Mortgage Loans," repurchasing all of the Mortgage Loans.

The Depositor maintains its principal office at 8480 Stagecoach Circle, Frederick, Maryland 21701. Its telephone number is (240) 586-5999.

See "The Depositor" in the prospectus for more information about the Depositor.

THE ISSUING ENTITY

The Issuing Entity will be a New York common law trust (the "Trust"), formed on the Closing Date pursuant to the Pooling and Servicing Agreement. The Mortgage Loans will be deposited by the Depositor into the Trust under the Pooling and Servicing Agreement. The Trust will have no officers or directors and no continuing duties other than to hold the assets underlying the Certificates and to issue the Certificates. The fiscal year end of the Issuing Entity will be December 31. The Trust will be administered by the Trustee and the Master Servicer pursuant to the terms of the Pooling and Servicing Agreement.

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THE TRUSTEE

HSBC Bank USA, National Association ("HSBC Bank") will act as trustee (the "Trustee") under the Pooling and Servicing Agreement. HSBC Bank is a national banking association. The Depositor and the Master Servicer may maintain other banking relationships in the ordinary course of business with the Trustee. The Trustee's corporate trust office is located at 452 Fifth Avenue, New York, New York 10018, Attention: Corporate Trust or at such other address as the Trustee may designate from time to time.

HSBC Bank, has been, and currently is, serving as trustee for numerous securities transactions involving similar residential mortgage pool assets to those found in this transaction.

The Trustee has limited administrative responsibilities under the terms of the Pooling and Servicing Agreement. The Trustee is not responsible for securities administration, does not monitor access to and activity in the Certificate Account or compliance with covenants in the Pooling and Servicing Agreement. Under the Pooling and Servicing Agreement, the Trustee will be required to make Periodic Advances to the limited extent described herein with respect to the Mortgage Loans serviced by Wells Fargo Bank if Wells Fargo Bank, as Servicer, fails to make a Periodic Advance required by the related Underlying Servicing Agreement. See "Description of the Certificates -- Periodic Advances" herein.

The Trustee may appoint one or more co-trustees if necessary to comply with the fiduciary requirements imposed by any jurisdiction in which a Mortgaged Property is located. In the case of any appointment of a co-trustee, all rights, powers, duties and obligations conferred or imposed upon the Trustee will be conferred or imposed upon and exercised or performed by the Trustee and the co-trustee jointly, unless the law of a jurisdiction prohibits the Trustee from performing its duties under the Pooling and Servicing Agreement, in which event such rights, powers, duties and obligations (including the holding of title to the Trust or any portion of the Trust in any such jurisdiction) shall be exercised and performed by the co-trustee at the direction of the Trustee.

See "The Pooling and Servicing Agreement--The Trustee" in the prospectus for more information about the Trustee and its obligations and rights (including the right to indemnity and reimbursement in certain circumstances) under the Pooling and Servicing Agreement.

THE MASTER SERVICER

The Corporate Trust Services division of Wells Fargo Bank will act as master servicer (the "Master Servicer") of the Mortgage Loans and, in that capacity, will supervise the servicing of the Mortgage Loans, cause the Mortgage Loans to be serviced in the event a Servicer (other than Wells Fargo Bank) is terminated and a successor servicer is not appointed, provide certain reports to the Certificateholders regarding the Mortgage Loans and the Certificates and make Periodic Advances to the limited extent described herein. See "Description of the Certificates--Periodic Advances" herein. As of the date of this prospectus supplement, the Master Servicer has not failed to make any required Periodic Advance with respect to any issuance of residential mortgage backed securities.

In addition, the Master Servicer will be responsible for securities administration of the Trust. In such capacity, the Master Servicer is responsible for pool performance calculation, distribution calculations, the preparation of monthly distribution reports and the preparation of tax returns on behalf of the Trust and the preparation of monthly reports on Form 10-D (based on information included in the monthly distribution date statements), annual reports on Form 10-K and certain reports on Form 8-K that are required to be filed with the SEC on behalf of the Trust.

Under the Pooling and Servicing Agreement, any good faith interpretation of the Master Servicer of any provisions of the Pooling and Servicing Agreement relating to the distributions to be made on or the allocation of any losses to the Certificates which the Master Servicer concludes are ambiguous or unclear will be binding on Certificateholders.

See "The Sponsor" in the prospectus for more information about Wells Fargo Bank and "Servicing of the Mortgage Loans--The Master Servicer" in the prospectus for more information about Wells Fargo Bank in its capacity as Master Servicer.

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THE PAYING AGENT

The Corporate Trust Services division of Wells Fargo Bank will also act as paying agent (the "Paying Agent") under the Pooling and Servicing Agreement. The Paying Agent is responsible for making distributions to Certificateholders. The Paying Agent will establish and maintain a payment account which will be a trust account and which may be the Certificate Account for so long as the Master Servicer is also acting as the Paying Agent (the "Payment Account"). On each Distribution Date or, if Wells Fargo is no longer acting as Paying Agent, on the business day prior to each Distribution Date, the Master Servicer will deposit funds from the Certificate Account into the Payment Account. The Paying Agent will make payments to Certificateholders with the funds in the Payment Account on the related Distribution Date.

See "The Sponsor" in the prospectus for more information about Wells Fargo Bank.

THE SERVICER

As of the Closing Date, the Sponsor, as "Servicer," will service all of the Mortgage Loans in accordance with the terms of the servicing agreement, dated the Closing Date (the "Wells Fargo Underlying Servicing Agreement" or the "Underlying Servicing Agreement") between the Master Servicer and the Servicer. As of the Closing Date, there are no other Servicers servicing the Mortgage Loans. The rights to enforce the Servicer's obligations under the Wells Fargo Underlying Servicing Agreement with respect to the related Mortgage Loans will be assigned to the Trustee for the benefit of Certificateholders. Among other things, the Servicer is obligated under certain circumstances to advance delinquent payments of principal and interest with respect to the Mortgage Loans. As of the date of this prospectus supplement, the Servicer has not failed to make any required advance with respect to any issuance of residential mortgage backed securities.

The Servicer may perform any of its obligations under the Wells Fargo Underlying Servicing Agreement through one or more subservicers, although the Servicer has not engaged any subservicers as of the date of this prospectus supplement. Despite the existence of subservicing arrangements, the Servicer will be liable for its servicing duties and obligations under the Wells Fargo Underlying Servicing Agreement as if the Servicer alone were servicing the Mortgage Loans.

See "The Sponsor," "Servicing of the Mortgage Loans--The Servicers," "--Servicing Experience and Procedures of Wells Fargo Bank" and "The Pooling and Servicing Agreement" in the prospectus for more information about the Sponsor, the Sponsor's experience, its servicing procedures and its obligations under the Pooling and Servicing Agreement.

All of the Mortgage Loans will be Type 1 Loans. See "Description of the Certificates--Distributions to Certificateholders--Unscheduled Principal Receipts" and "Servicing of the Mortgage Loans--Changes in Servicing" in the prospectus.

See "Servicing of the Mortgage Loans" in the prospectus.

THE CUSTODIAN

Wells Fargo Bank will act as custodian (the "Custodian") of the mortgage files pursuant to the custodial agreement, dated the Closing Date (the "Custodial Agreement") among the Trustee, the Depositor, the Master Servicer and the Custodian. In that capacity, Wells Fargo Bank is responsible to hold and safeguard the Mortgage Notes and other contents of the mortgage files on behalf of the Trustee and the Certificateholders. Wells Fargo Bank maintains each mortgage loan file in a separate file folder marked with a unique bar code to assure loan-level file integrity and to assist in inventory management. The mortgage files are segregated by transaction or investor. Wells Fargo Bank has been engaged in the mortgage document custody business for more than 25 years. Wells Fargo Bank maintains document custody facilities in its Minneapolis, Minnesota headquarters and in two regional offices located in Irvine, California, and Salt Lake City, Utah. As of December 31, 2007, Wells Fargo Bank maintains mortgage custody vaults in each of those locations with an aggregate capacity of over ten million files.

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See "The Pooling and Servicing Agreement--The Custodian" in the prospectus for more information about the Custodian and its obligations and rights (including its right to indemnity in certain circumstances) under the Pooling and Servicing Agreement.

ROLES OF WELLS FARGO BANK

As discussed herein, Wells Fargo Bank is the Sponsor and will act as the Custodian, the Master Servicer, the Paying Agent and the Servicer with respect to the Mortgage Loans. Even though Wells Fargo Bank will be acting in these multiple capacities, it is expected that with respect to the functions of Master Servicer, Paying Agent and Custodian, on the one hand, and Servicer, on the other, different divisions within Wells Fargo Bank, acting through different personnel, will be performing these functions. See "Summary Information-Affiliations" in this prospectus supplement.

DESCRIPTION OF THE CERTIFICATES

General

The Issuing Entity will issue Mortgage Asset-Backed Pass-Through Certificates, Series 20 - (the "Certificates") on the Closing Date.

The Certificates will consist of seventeen classes of senior certificates (the "Class A Certificates") and six classes of junior certificates (the "Class B Certificates" or "Subordinated Certificates"). The Class A Certificates (other than the Class A-PO Certificates) are referred to herein as the "Class A Non-PO Certificates." Only the Class A Certificates and the Class B-1, Class B-2 and Class B-3 Certificates are being offered by this prospectus supplement and the accompanying prospectus (the "Offered Certificates"). The Offered Certificates will be issued in the forms and denominations set forth in the table beginning on page S-6.

Book-Entry Certificates

Persons acquiring beneficial ownership interests in the Book-Entry Certificates will hold such Certificates through The Depository Trust Company (in the United States), or Clearstream or Euroclear (in Europe) under certain circumstances as more fully described in the prospectus under "Description of the Certificates--Book-Entry Form."

Distributions

On each Distribution Date, the Paying Agent will make monthly distributions of interest and in reduction of Principal Balance to holders of each Class of Certificates, to the extent of each Class's entitlement thereto. Distributions will be made on each Distribution Date to holders of record (which, in the case of the Book-Entry Certificates, will be Cede, as nominee for DTC) at the close of business on (i) in the case of the Floating Rate and Inverse Floating Rate Certificates, the business day preceding such Distribution Date and (ii) for all other Certificates, the last business day of the preceding month (each, a "Record Date"). Distributions on the Offered Certificates will be made by either wire transfer or by check mailed to the person entitled thereto as it appears on the certificate register, as described in the prospectus under "Description of the Certificates-General."

The aggregate amount available for distribution to the Certificateholders on each Distribution Date will be the Pool Distribution Amount. The "Pool Distribution Amount" for a Distribution Date will be the sum of:

(i) all previously undistributed payments or other receipts on account of principal (including principal prepayments and Liquidation Proceeds in respect of principal, if any), and interest on or in respect of the Mortgage Loans received by the Master Servicer, including without limitation any related insurance proceeds, any proceeds received as a result of a substitution of a Mortgage Loan and the proceeds of any purchase of a related Mortgage Loan for breach of a representation or warranty or the sale of a Mortgaged Property by a Servicer in connection with the liquidation of the related Mortgage Loan on or prior to the Remittance Date in the month in which such Distribution Date occurs;

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(ii) all Periodic Advances made; and

(iii) all other amounts (including any insurance proceeds and Compensating Interest) placed in the Certificate Account by any Servicer on or before the Remittance Date or by the Master Servicer on or before the Distribution Date pursuant to the Pooling and Servicing Agreement, but excluding the following:

(a) amounts received as late payments of principal or interest as to which one or more unreimbursed Periodic Advances has been made;

(b) those portions of each payment of interest on a particular Mortgage Loan which represent (i) the applicable Servicing Fee, (ii) the Master Servicing Fee and (iii) the Fixed Retained Yield, if any;

(c) all amounts representing scheduled payments of principal and interest due after the Due Date occurring in the month in which such Distribution Date occurs;

(d) all Unscheduled Principal Receipts that were received by the Servicers after the Unscheduled Principal Receipt Period relating to the Distribution Date for the applicable type of Unscheduled Principal Receipt, and all related payments of interest on such amounts;

(e) all repurchase proceeds with respect to the Mortgage Loans repurchased by the Depositor on or following the Determination Date in the month in which such Distribution Date occurs and the excess of the unpaid principal balance of any Mortgage Loan for which a Mortgage Loan was substituted over the unpaid principal balance of such substitute Mortgage Loan on or following the Determination Date in the month in which such Distribution Date occurs;

(f) to the extent permitted by the Pooling and Servicing Agreement, that portion of Liquidation Proceeds or insurance proceeds with respect to a Mortgage Loan or proceeds of any Mortgaged Property that becomes owned by the Trust Estate which represents (i) any unpaid Servicing Fee or Master Servicing Fee to which such Servicer or the Master Servicer, respectively, is entitled, (ii) any unpaid Fixed Retained Yield or (iii) any unreimbursed Periodic Advances;

(g) all amounts representing certain expenses reimbursable to the Master Servicer, any Servicer or the Trustee and other amounts permitted to be retained by the Master Servicer or any Servicer or withdrawn by the Master Servicer from the Certificate Account pursuant to the Pooling and Servicing Agreement;

(h) reinvestment earnings on payments received in respect of the Mortgage Loans or on other amounts on deposit in the Certificate Account;

(i) Liquidation Profits;

(j) Month End Interest; and

(k) amounts reimbursable to a Servicer for PMI Advances.

See "Description of the Certificates -- Distributions to Certificateholders" in the prospectus.

Each Servicer is required to deposit in the Certificate Account by the Remittance Date certain amounts in respect of the Mortgage Loans as set forth in the prospectus under "Servicing of the Mortgage Loans -- Payments on Mortgage Loans." The Master Servicer is required to cause to be remitted to the Payment Account on or prior to the Distribution Date any payments constituting part of the Pool Distribution Amount that are received by the Master Servicer or are required to be made with the Master Servicer's own funds. Except as described below under "-- Periodic Advances," neither the Master Servicer nor the Paying Agent is obligated to remit any amounts which a Servicer was required but failed to deposit in the Certificate Account.

On each Distribution Date, the Pool Distribution Amount will be allocated among the Classes of Certificates and distributed to the holders thereof of record as of the related Record Date as follows (the "Pool Distribution Amount Allocation"):

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first, to the Classes of Class A Certificates, pro rata, based on their respective Interest Accrual Amounts, in an aggregate amount up to the sum of their Interest Accrual Amounts with respect to such Distribution Date; provided that prior to the applicable Accretion Termination Date, an amount equal to the amount that would otherwise be distributable in respect of interest to a Class of Accrual Certificates pursuant to this provision will be distributed in reduction of the Principal Balances of certain Classes of Class A Certificates as set forth below under "--Principal (Including Prepayments)--Allocation of Amount to be Distributed on the Class A Certificates";

second, to the Classes of Class A Certificates, pro rata, based on their respective unpaid Interest Shortfall Amounts, in an aggregate amount up to the sum of their unpaid Interest Shortfall Amounts; provided that prior to the applicable Accretion Termination Date, an amount equal to the amount that would otherwise be distributable in respect of interest shortfalls to a Class of Accrual Certificates pursuant to this provision will be distributed in reduction of the Principal Balances of certain Classes of Class A Certificates as set forth below under "--Principal (Including Prepayments)--Allocation of Amount to be Distributed on the Class A Certificates";

third, concurrently, pro rata, to (A) the Class A Non-PO Certificates, based on and up to the Class A Non-PO Optimal Principal Amount, and (B) the Class A-PO Certificates, based on and up to the Class A-PO Optimal Principal Amount;

fourth, to the Class A-PO Certificates in an amount up to the Class A-PO Deferred Amount, but only from amounts otherwise distributable (without regard to this priority) to the Classes of Class B Certificates in reverse order of priority from their respective Class B Principal Distribution Amounts; and

fifth, sequentially to the Class B-1, Class B-2, Class B-3, Class B-4, Class B-5 and Class B-6 Certificates so that each such Class shall receive (A) first, an amount up to its Interest Accrual Amount with respect to such Distribution Date, (B) then, an amount up to its previously unpaid Interest Shortfall Amounts and (C) finally, an amount up to its Class B Optimal Principal Amount before any Classes of Class B Certificates with higher numerical designations receive any payments in respect of interest or principal; provided, however, that the amount distributable pursuant to this priority fifth clause (C) to any Classes of Class B Certificates will be reduced by the amount, if any, otherwise distributable as principal hereunder used to pay the Class A-PO Deferred Amount in accordance with priority fourth above.

The undivided percentage interest (the "Percentage Interest") represented by any Offered Certificate of a Class will be equal to the percentage obtained by dividing the initial principal balance of such Certificate by the initial Principal Balance of such Class.

Interest

Interest will accrue on each interest-bearing Class of Certificates (other than the Floating Rate and Inverse Floating Rate Certificates) during each one-month period ending on the last day of the month preceding the month in which each Distribution Date occurs (each, a "Regular Interest Accrual Period"). The initial Regular Interest Accrual Period will be deemed to have commenced on the Cut-Off Date. Interest which accrues on such Classes of Certificates will be calculated on the assumption that distributions in reduction of the Principal Balances thereof on a Distribution Date are made on the first day of the month of each Distribution Date. Interest will accrue on the Floating Rate and Inverse Floating Rate Certificates during each one-month period commencing on the 25th day of the month preceding the month in which such Distribution Date occurs and ending on the 24th day of the month in which such Distribution Date occurs (each, a "LIBOR Based Interest Accrual Period" and, together with each Regular Interest Accrual Period, an "Interest Accrual Period"). The initial LIBOR Based Interest Accrual Period will be deemed to have commenced on [_____], 20 .

The amount of interest that will accrue on each interest-bearing Class of Certificates during each Interest Accrual Period, after taking into account any Non-Supported Interest Shortfalls, Relief Act Shortfalls and the interest portion of certain losses allocated to such Class, is referred to herein as the "Interest Accrual Amount" for such Class.

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The Interest Accrual Amount for each interest-bearing Class of Certificates equals (a) the product of (i) (1)/12th of the Pass-Through Rate for such Class and (ii) the outstanding Principal Balance of such Class minus (b) the sum of (i) any Non-Supported Interest Shortfall allocable to such Class,
(ii) any Relief Act Shortfall allocable to such Class and (iii) in the case of the Class A Certificates, the interest portion of any Realized Losses allocable to such Class on or after the Subordination Depletion Date. The pass-through rate (the "Pass-Through Rate") for each Class of Certificates is the percentage set forth or described in the table beginning on page S-6 of this prospectus supplement. Interest on each Class of Certificates will be calculated on the basis of a 360-day year consisting of twelve 30-day months. The Pass-Through Rates on the Floating Rate and Inverse Floating Rate Certificates will be determined as described in the prospectus under "Description of the Certificates -- Pass-Through Rates Based on LIBOR" and may be obtained by telephoning the Paying Agent at 866-846-4526 during normal working hours on any business day.

No interest will accrue on the Principal Only Certificates.

Subject to the adjustment described below, the "Principal Balance" of a Class of Certificates as of any date will be the principal balance of such Class on the date of initial issuance of the Certificates, plus, in the case of a Class of Accrual Certificates, any applicable Accrual Distribution Amounts, less all amounts previously distributed on such Class in reduction of the principal balance of such Class on prior Distribution Dates including, in the case of the Class A-PO Certificates, distributions in respect of the Class A-PO Deferred Amount.

After distributions of principal have been made on a Distribution Date, the Principal Balances of the Certificates will be adjusted so that they equal the Adjusted Pool Amount for such Distribution Date. Such adjustment could result in an increase or decrease in the Principal Balance of a Class. Prior to the Subordination Depletion Date, the most subordinate Class of Class B Certificates then outstanding will be subject to the adjustment. After the Subordination Depletion Date, the Principal Balance of the Class A-PO Certificates will be adjusted to equal the Adjusted Pool Amount (PO Portion) and the Principal Balances of the Class A Non-PO Certificates will be adjusted to equal the Adjusted Pool Amount (Non-PO Portion). Any adjustment to the Class A Non-PO Certificates will be allocated among the Class A Non-PO Certificates, pro rata, based on their Principal Balances or, in the case of a Class of Accrual Certificates, the initial Principal Balance, if lower.

Notwithstanding the foregoing, the Principal Balance of a Class may not be increased such that it exceeds the initial Principal Balance of such Class (plus any applicable Accrual Distribution Amounts previously added to the Principal Balance of a Class of Accrual Certificates) less all amounts previously distributed on such Class in reduction of the Principal Balance thereof.

A Recovery with respect to a loss on a Mortgage Loan will be treated as a principal prepayment and will result in a payment of principal to one or more corresponding then-outstanding Classes of Certificates. A Class will cease to be entitled to any distribution after its Principal Balance is reduced to zero for any reason. It is possible that such payment will not be made to the Class that originally bore the loss. Further, even though a Class may have previously had its Principal Balance reduced as a result of a loss for which there is later a Recovery, that Class will not be entitled to any interest on the amount of such reduction. Because a Recovery results in a payment of principal to certain Classes without a corresponding decrease in the related Adjusted Pool Amount, the Principal Balance of the most subordinate Class then outstanding (which may not be the Class that originally bore the loss if such Class is no longer outstanding) may be increased or such Principal Balance may be decreased by a lesser amount than would otherwise be the case based on any Realized Losses allocable to such Class.

The "Class A Principal Balance" as of any date will be equal to the sum of the Principal Balances of the Classes of Class A Certificates as of such date.

The "Class A Non-PO Principal Balance" as of any date will be equal to the sum of the Principal Balances of the Classes of Class A Non-PO Certificates as of such date.

The "Class B Principal Balance" as of any date will be equal to the sum of the Principal Balances of the Classes of Class B Certificates as of such date.

The "Aggregate Principal Balance" as of any date will be equal to the sum of the Class A Principal Balance and the Class B Principal Balance as of such date.

S-30

The "Aggregate Non-PO Principal Balance" as of any date will be equal to the sum of the Class A Non-PO Principal Balance and the Class B Principal Balance as of such date.

With respect to any Distribution Date, the "Adjusted Pool Amount" will equal the aggregate unpaid principal balance of the Mortgage Loans as of the Cut-Off Date minus the sum of (i) all amounts in respect of principal received in respect of such Mortgage Loans (including amounts received as Periodic Advances, principal prepayments and Liquidation Proceeds in respect of principal) and distributed to holders of the Certificates on such Distribution Date and all prior Distribution Dates, (ii) the principal portion of all Liquidated Loan Losses incurred on such Mortgage Loans for which the Liquidation Proceeds were received from the Cut-Off Date through the end of the applicable Unscheduled Principal Receipt Period for such Distribution Date and (iii) the principal portion of all Bankruptcy Losses (other than Debt Service Reductions) incurred on such Mortgage Loans from the Cut-Off Date through the end of the period which corresponds to the applicable Unscheduled Principal Receipt Period for principal prepayments in full for such Distribution Date.

With respect to any Distribution Date, the "Adjusted Pool Amount (PO Portion)" will equal the sum as to each Mortgage Loan outstanding as of the Cut-Off Date of the product of (A) the PO Fraction for such Mortgage Loan and (B) the principal balance of such Mortgage Loan as of the Cut-Off Date less the sum of (i) all amounts in respect of principal received in respect of such Mortgage Loan (including amounts received as Periodic Advances, principal prepayments and Liquidation Proceeds in respect of principal) and distributed to holders of the Certificates on such Distribution Date and all prior Distribution Dates, (ii) the principal portion of any Liquidated Loan Losses incurred on such Mortgage Loan for which the Liquidation Proceeds were received from the Cut-Off Date through the end of the applicable Unscheduled Principal Receipt Period for such Distribution Date and (iii) the principal portion of all Bankruptcy Losses (other than Debt Service Reductions) incurred on such Mortgage Loan from the Cut-Off Date through the end of the period which corresponds to the applicable Unscheduled Principal Receipt Period for principal prepayments in full for such Distribution Date.

With respect to any Distribution Date, the "Adjusted Pool Amount (Non-PO Portion)" will equal the Adjusted Pool Amount less the Adjusted Pool Amount (PO Portion).

The "Net Mortgage Interest Rate" on each Mortgage Loan will be equal to the Mortgage Interest Rate on such Mortgage Loan as stated in the related mortgage note, as the same may be amended in accordance with any Servicer Modification, minus the sum of (i) the applicable Servicing Fee Rate, (ii) the Master Servicing Fee Rate and (iii) the Fixed Retained Yield rate, if any, for such Mortgage Loan. See "Pooling and Servicing Agreement--Fixed Retained Yield" herein.

As to any Distribution Date, Prepayment Interest Shortfalls, to the extent that they exceed Compensating Interest, and Curtailment Interest Shortfalls are referred to herein as "Non-Supported Interest Shortfalls" and will be allocated to (i) the Class A Certificates according to the percentage obtained by dividing the sum of the Class A Non-PO Principal Balances by the Aggregate Non-PO Principal Balance and (ii) the Class B Certificates according to the percentage obtained by dividing the Class B Principal Balance by the Aggregate Non-PO Principal Balance. Such allocation of Non-Supported Interest Shortfalls will reduce the amount of interest due to be distributed to holders of Certificates then entitled to distributions in respect of interest. Any such reduction in respect of interest allocated to the Class A Certificates will be allocated among the Classes of Class A Certificates, pro rata, on the basis of their respective Interest Accrual Amounts, without regard to any reduction pursuant to this paragraph, for such Distribution Date. Any such reduction in respect of interest allocated to the Class B Certificates will be allocated among such Classes of Class B Certificates, pro rata, on the basis of their respective Interest Accrual Amounts, without regard to any reduction pursuant to this paragraph, for such Distribution Date.

Any interest shortfalls arising from Unscheduled Principal Receipts in full that are not Prepayments in Full and any other interest shortfalls arising from Unscheduled Principal Receipts, other than Curtailments, will be borne first by the Classes of Class B Certificates in reverse numerical order and then pro rata by the Class A Certificates, based on interest accrued. See "-- Subordination of Class B Certificates" herein. After the Subordination Depletion Date, all interest shortfalls arising from Unscheduled Principal Receipts, other than Prepayment Interest Shortfalls covered by Compensating Interest, will be treated as Non-Supported Interest Shortfalls and allocated in reduction of interest accrued on the Class A Certificates.

S-31

See "Description of the Certificates -- Distributions to Certificateholders -- Distributions of Interest" in the prospectus for a discussion of Prepayment Interest Shortfalls, Curtailment Interest Shortfalls and Compensating Interest.

Any interest shortfalls arising as a result of the reduction in the amount of monthly interest payments on any Mortgage Loans as a result of the application of the Servicemembers Civil Relief Act, as it may be amended from time to time, or comparable state legislation ("Relief Act Shortfalls") will be allocated among the Class A Certificates and Class B Certificates in the same manner as Non-Supported Interest Shortfalls.

Allocations of the interest portion of Realized Losses first to the Classes of Class B Certificates in reverse numerical order will result from the priority of distributions first to the Class A Certificates and then to the Classes of Class B Certificates in numerical order of the Pool Distribution Amount as described above under "-- Distributions."

On each Distribution Date on which the amount available to be distributed in respect of interest on a Class of Certificates pursuant to the Pool Distribution Amount Allocation is less than such Class's Interest Accrual Amount, the amount of any such deficiency (as to each Class, an "Interest Shortfall Amount") will be added to the amount of interest distributable with respect to such Class on subsequent Distribution Dates, but only for so long as such Class's Principal Balance is greater than zero. No interest will accrue on any Interest Shortfall Amounts.

Prior to the applicable Accretion Termination Date, interest in an amount equal to the Interest Accrual Amount for a Class of Accrual Certificates will accrue on such Class, but such amount will not be distributed as interest to such Class until such Accretion Termination Date. Prior to such time, an amount equal to the accrued and unpaid interest on such Class will be added to the Principal Balance thereof and distributed as described under "-- Principal (Including Prepayments) -- Allocation of Amount to be Distributed on the Class A Certificates" below. The "Accretion Termination Date" will be (a) for the Class A-7 Certificates, the earlier to occur of (i) the Distribution Date following the Distribution Date on which the Principal Balances of the Class A-5 and Class A-6 Certificates have been reduced to zero or (ii) the Subordination Depletion Date and (b) for the Class A-9 Certificates, the earlier to occur of (i) the Distribution Date following the Distribution Date on which the Principal Balance of the Class A-8 Certificates has been reduced to zero or (ii) the Subordination Depletion Date. See "Prepayment and Yield Considerations" herein.

Principal (Including Prepayments)

The principal balance of a Certificate at any time is equal to the product of the related Class's Principal Balance and such Certificate's Percentage Interest, and represents the maximum specified dollar amount (exclusive of (i) any interest that may accrue on such Certificate (other than interest added to the Principal Balance of a Class of Accrual Certificates) and (ii) in the case of the Residual Certificates, any additional amounts to which the holders of such Certificates may be entitled as described below under "--Additional Rights of the Residual Certificateholders") to which the holders thereof are entitled from the cash flow on the Mortgage Loans at such time and will decline to the extent of distributions in reduction of the principal balance of, and allocations of losses to, such Certificate. The approximate initial Principal Balance of each Class of Certificates is set forth in the table beginning on page S-6 of this prospectus supplement.

Calculation of Amount to be Distributed on the Certificates

Distributions in reduction of the Principal Balance of the Class A Non-PO Certificates will be made on each Distribution Date pursuant to the Pool Distribution Amount Allocation, in an aggregate amount equal to the Class A Non-PO Principal Distribution Amount with respect to such Distribution Date and any Accrual Distribution Amounts for the Classes of Accrual Certificates with respect to such Distribution Date.

The "Accrual Distribution Amount" with respect to any Distribution Date and any Class of Accrual Certificates will be equal to the sum of (i) the current interest allocated but not distributed to such Class of Accrual Certificates on such Distribution Date in accordance with priority first of the Pool Distribution Amount Allocation and (ii) the unpaid Interest Shortfall Amount allocated but not distributed to such Class of Accrual Certificates on such Distribution Date in accordance with priority second of the Pool Distribution Amount Allocation.

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The "Class A Non-PO Principal Distribution Amount" with respect to any Distribution Date will be equal to the amount distributed pursuant to priority third clause (A) of the Pool Distribution Amount Allocation, in an aggregate amount up to the Class A Non-PO Optimal Principal Amount.

Distributions in reduction of the Principal Balance of the Class A-PO Certificates will be made on each Distribution Date in an aggregate amount equal to the Class A-PO Distribution Amount. The "Class A-PO Distribution Amount" with respect to any Distribution Date will be equal to the sum of (i) the amount distributed pursuant to priority third clause (B) of the Pool Distribution Amount Allocation, in an aggregate amount up to the Class A-PO Optimal Principal Amount and (ii) the amount distributed pursuant to priority fourth of the Pool Distribution Amount Allocation, in an aggregate amount up to the Class A-PO Deferred Amount.

Distributions in reduction of the Principal Balances of the Class B-1, Class B-2, Class B-3, Class B-4, Class B-5 and Class B-6 Certificates will be made on each Distribution Date first to the Class B-1 Certificates, second to the Class B-2 Certificates, third to the Class B-3 Certificates, fourth to the Class B-4 Certificates, fifth to the Class B-5 Certificates and then to the Class B-6 Certificates, pursuant to priority fifth clause (C) of the Pool Distribution Amount Allocation, in an aggregate amount with respect to each such Class (each, a "Class B Principal Distribution Amount") up to the Class B Optimal Principal Amount for such Class.

The "Class A Non-PO Optimal Principal Amount", the "Class B Optimal Principal Amount" for each Class of Class B Certificates and the "Class A-PO Optimal Principal Amount" with respect to each Distribution Date will be an amount equal to the sum of:

(I) for each outstanding Mortgage Loan (including each defaulted Mortgage Loan with respect to which the related Mortgaged Property has been acquired by the Trust Estate) of the product of:

(A) (i) in the case of the Class A Non-PO Optimal Principal Amount and each Class B Optimal Principal Amount, the Non-PO Fraction for such Mortgage Loan and (ii) in the case of the Class A-PO Optimal Principal Amount, the PO Fraction for such Mortgage Loan; and

(B) the sum of:

(i) the applicable Class Percentage of the scheduled payment of principal due on such Mortgage Loan on the first day of the month in which the Distribution Date occurs;

(ii) the applicable Class Prepayment Percentage of all Unscheduled Principal Receipts (other than Recoveries) that were received by a Servicer with respect to such Mortgage Loan during the Unscheduled Principal Receipt Period relating to such Distribution Date for each applicable type of Unscheduled Principal Receipt, less the amount allocable to the principal portion of any unreimbursed advances in respect of such Mortgage Loan;

(iii) the applicable Class Prepayment Percentage of the Scheduled Principal Balance of such Mortgage Loan which, during the one month period ending on the day preceding the Determination Date for such Distribution Date, was repurchased by the Depositor, as described under the heading "Description of the Mortgage Loans -- Mandatory Repurchase or Substitution of Mortgage Loans" herein; and

(iv) the applicable Class Percentage of the excess of the unpaid principal balance of any Mortgage Loan for which a Mortgage Loan was substituted during the one month period ending on the day preceding the Determination Date for such Distribution Date over the unpaid principal balance of such substitute Mortgage Loan, less the amount allocable to the principal portion of any unreimbursed advances in respect of such Mortgage Loan. See "The Pooling and Servicing Agreement -- Assignment of Mortgage Loans to the Trustee" in the prospectus; and

(II) in the case of the Class A-PO Certificates, the PO Fraction of each Recovery in an aggregate amount not exceeding the Class A-PO Deferred Amount and in the case of the Class A Non-PO Certificates and each Class of Class B Certificates, the applicable Class Prepayment Percentage of the Recoveries not allocated to the Class A-PO Certificates.

S-33

The "Class Percentage" will equal (i) the Class A Percentage, in the case of the calculation of the Class A Non-PO Optimal Principal Amount; (ii) the applicable Class B Percentage, in the case of the calculation of the Class B Optimal Principal Amount for a Class of Class B Certificates; and (iii) 100% in the case of the calculation of the Class A-PO Optimal Principal Amount.

The "Class Prepayment Percentage" will equal (i) the Class A Prepayment Percentage, in the case of the calculation of the Class A Non-PO Optimal Principal Amount; (ii) the applicable Class B Prepayment Percentage, in the case of the calculation of the Class B Optimal Principal Amount for a Class of Class B Certificates; and (iii) 100% in the case of the calculation of the Class A-PO Optimal Principal Amount.

The "Class A-PO Deferred Amount" for any Distribution Date prior to the Subordination Depletion Date will equal the difference between:

(A) the sum of:

(i) the amount by which the Class A-PO Optimal Principal Amount for all prior Distribution Dates exceeds the amounts distributed to the Class A-PO Certificates on such prior Distribution Dates pursuant to priority third clause (B) of the Pool Distribution Amount Allocation; and

(ii) the sum of the product for each Discount Mortgage Loan which became a Liquidated Loan at any time on or prior to the last day of the applicable Unscheduled Principal Receipt Period for the current Distribution Date of:

(a) the PO Fraction for such Discount Mortgage Loan; and

(b) an amount equal to the principal portion of Realized Losses (other than Bankruptcy Losses due to Debt Service Reductions) incurred with respect to such Discount Mortgage Loan; and

(B) the sum of:

(i) the sum of the Class A-PO Certificates' portion of Recoveries for such Distribution Date and prior Distribution Dates; and

(ii) amounts distributed on the Class A-PO Certificates on prior Distribution Dates pursuant to priority fourth of the Pool Distribution Amount Allocation.

On or after the Subordination Depletion Date, the Class A-PO Deferred Amount will be zero. No interest will accrue on any Class A-PO Deferred Amount.

Class A-PO Deferred Amounts are payable only from amounts available to make principal distributions on the Class B Certificates. While the Principal Balances of any of the Class A Non-PO Certificates are greater than zero, the Class B Certificates will receive no distributions of principal for a five-year period with respect to Unscheduled Principal Receipts or as a result of the repurchase of Mortgage Loans by the Depositor. Amounts available to pay Class A-PO Deferred Amounts and the timing thereof will be affected by these factors.

The Principal Balance of the Class A-PO Certificates will not be reduced by distributions of amounts representing Class A-PO Deferred Amounts.

The principal distribution to the holders of a Class of Class B Certificates will be reduced on any Distribution Date on which (i) the Principal Balance of such Class of Class B Certificates would be reduced to zero as a result of principal distributions or allocation of losses and (ii) the Principal Balance of any Class A Certificates or any Class of Class B Certificates with a lower numerical designation, would be subject to reduction as a result of allocation of Realized Losses. The amount of any such reduction in the principal distributed to the holders of such Class of Class B Certificates will instead be distributed pro rata to the holders of any Class (but not the Class A-PO Certificates) senior in priority to receive distributions in accordance with the Pool Distribution Amount Allocation.

The "Non-PO Fraction" with respect to any Mortgage Loan will equal the Net Mortgage Interest Rate for such Mortgage Loan divided by [__]%, but will not be greater than 1.0.

S-34

The "Pool Balance (Non-PO Portion)" for any Distribution Date is the sum for each outstanding Mortgage Loan of the product of (i) the Non-PO Fraction for such Mortgage Loan and (ii) the Scheduled Principal Balance of such Mortgage Loan as of such Distribution Date.

The "PO Fraction" with respect to any Mortgage Loan with a Net Mortgage Interest Rate less than [_____]% (a "Discount Mortgage Loan"), will equal the difference between [_____] and the Non-PO Fraction for such Mortgage Loan. The PO Fraction with respect to each Mortgage Loan that is not a Discount Mortgage Loan (a "Premium Mortgage Loan") will be zero.

The "Pool Balance (PO Portion)" for any Distribution Date is the sum for each outstanding Mortgage Loan of the product of (i) the PO Fraction for such Mortgage Loan and (ii) the Scheduled Principal Balance of such Mortgage Loan as of such Distribution Date.

The "Class A Percentage" for any Distribution Date occurring on or prior to the Subordination Depletion Date is the percentage, which in no event will exceed 100%, obtained by dividing the Class A Non-PO Principal Balance as of such date (before taking into account distributions in reduction of Principal Balance on such date) by the Pool Balance (Non-PO Portion). The Class A Percentage for the first Distribution Date will be approximately [_____]%. The Class A Percentage for any Distribution Date occurring after the Subordination Depletion Date will be [_____]%.

The "Class A Prepayment Percentage" for any Distribution Date prior to the Distribution Date in [_____] 20 will be [_____]% and thereafter will be the Class A Percentage for such Distribution Date plus the percentage of the Subordinated Percentage indicated in the table below; provided, however, that if on any Distribution Date the Class A Percentage exceeds the initial Class A Percentage, the Class A Prepayment Percentage for such Distribution Date will equal [_____]%. See "Prepayment and Yield Considerations" herein and in the prospectus. Notwithstanding the foregoing, no reduction of the level of the Class A Prepayment Percentage will occur on any Distribution Date if the Delinquency and Loss Tests are not met.

The "Delinquency and Loss Tests" with respect to any Distribution Date are met if (i) as of such Distribution Date as to which any reduction in the Class A Prepayment Percentage applies, the average outstanding principal balance on such Distribution Date and for the preceding five Distribution Dates of the Mortgage Loans that were delinquent 60 days or more (including for this purpose any Mortgage Loans in foreclosure, any Mortgage Loans with respect to which the related Mortgaged Property has been acquired by the Trust Estate and any Mortgage Loans in such Loan Group that were the subject of a Servicer Modification within twelve months prior to such Distribution Date) is less than
[_____]% of the Class B Principal Balance and (ii) for any Distribution Date, cumulative Realized Losses with respect to the Mortgage Loans are less than or equal to the percentages of the principal balance of the Class B Certificates as of the Closing Date (the "Original Class B Principal Balance") indicated in the table below.

                                 Percentage of     Percentage of
                                 Subordinated    Original Class B
Distribution Date Occurring In    Percentage     Principal Balance
------------------------------   -------------   -----------------
                                       %                 %
                                       %                 %
                                       %                 %
                                       %                 %
                                       %                 %

If on any Distribution Date the allocation to the Class A Non-PO Certificates of full and partial principal prepayments and other amounts in the percentage required as described above would reduce the outstanding Class A Non-PO Principal Balance below zero, the Class A Prepayment Percentage for such Distribution Date will be limited to the percentage necessary to reduce the Class A Non-PO Principal Balance to zero.

This disproportionate allocation of certain unscheduled payments in respect of principal will have the effect of accelerating the amortization of the Class A Non-PO Certificates while, in the absence of Realized Losses, increasing the interest in the principal balance of the Mortgage Loans evidenced by the Class B Certificates. Increasing the respective interest of the Class B Certificates relative to that of the Class A Non-PO Certificates is intended to preserve the availability of the subordination provided by the Class B Certificates. See "--Subordination of Class B Certificates" below.

S-35

A "Servicer Modification" with respect to a Mortgage Loan is a permanent modification to the terms of such Mortgage Loan as to which the Mortgagor is in default or as to which, in the judgment of the Servicer, default is reasonably foreseeable.

The "Subordinated Percentage" for any Distribution Date will be calculated as the difference between 100% and the Class A Percentage for such date. The "Subordinated Prepayment Percentage" for any Distribution Date will be calculated as the difference between 100% and the Class A Prepayment Percentage for such date.

The "Class B Percentage" and "Class B Prepayment Percentage" for a Class of Class B Certificates and any Distribution Date will equal the portion of the Subordinated Percentage and Subordinated Prepayment Percentage, as the case may be, represented by the fraction the numerator of which is the Principal Balance for such Class of Class B Certificates and the denominator of which is the sum of the Principal Balances of the Classes of Class B Certificates entitled to principal distributions for such Distribution Date as described below. In the event that a Class of Class B Certificates is not entitled to principal distributions for such Distribution Date, the Class B Percentage and Class B Prepayment Percentage for such Class will both be [_____]% with respect to such Distribution Date.

In the event that on any Distribution Date the Current Fractional Interest of any Class of Class B Certificates is less than the Original Fractional Interest of such Class, then the Classes of Certificates that are subordinate to such Class will not be entitled to distributions in respect of principal and the Principal Balances of such subordinated Classes will not be used to determine the Class B Percentages and Class B Prepayment Percentages of the Classes of Class B Certificates that are senior to such subordinated Classes for such Distribution Date. The Class B-6 Certificates will not have original or current fractional interests which are required to be maintained as described above.

The "Original Fractional Interest" of a Class of Class B Certificates is the percentage obtained by dividing the sum of the initial Principal Balances of the Classes of Certificates that are subordinate to such Class by the initial Aggregate Non-PO Principal Balance. The "Current Fractional Interest" of a Class of Class B Certificates for any Distribution Date is the percentage obtained by dividing the sum of the Principal Balances of the Classes of Certificates that are subordinate to such Class by the Aggregate Non-PO Principal Balance.

The following table sets forth the expected approximate Original Fractional Interest for each Class of Class B Certificates on the date of issuance of the Certificates.

        Approximate
         Original
        Fractional
Class    Interest
-----   -----------
B-1          %
B-2          %
B-3          %
B-4          %
B-5          %
B-6         N/A

Allocation of Amount to be Distributed on the Class A Certificates

I. On each Distribution Date occurring prior to the Accretion Termination Date for the Class A-7 Certificates, the applicable Accrual Distribution Amount will be distributed, sequentially, as follows:

first, concurrently, to the Class A-5 and Class A-6 Certificates, pro rata; and

second, to the Class A-7 Certificates.

II. On each Distribution Date occurring prior to the Accretion Termination Date for the Class A-9 Certificates, the applicable Accrual Distribution Amount will be distributed, sequentially, to the Class A-8 and Class A-9 Certificates;

III. On each Distribution Date occurring prior to the Subordination Depletion Date, the Class A Non-PO Distribution Amount will be allocated among and distributed in reduction of the Principal Balances of the Class A Non-PO Certificates, sequentially, as follows:

S-36

first, to the Class A-R Certificates; and

second, concurrently, as follows:

(A) approximately [_____]%, sequentially, as follows:

(i) sequentially, up to the PAC I Group Principal Amount as follows:

(a) sequentially, to the Class A-10 and Class A-11 Certificates;

(b) concurrently, to the Class A-12 and Class A-14 Certificates, pro rata; and

(c) to the Class A-13 Certificates;

(ii) sequentially, up to the PAC II Group Principal Amount, as follows:

(a) concurrently, to the Class A-5 and Class A-6 Certificates, pro rata; and

(b) to the Class A-7 Certificates;

(iii) sequentially, to the Class A-8 and Class A-9 Certificates;

(iv) sequentially, as follows:

(a) concurrently, to the Class A-5 and Class A-6 Certificates, pro rata; and

(b) to the Class A-7 Certificates; and

(v) sequentially, as follows:

(a) sequentially, to the Class A-10 and Class A-11 Certificates;

(b) concurrently, to the Class A-12 and Class A-14 Certificates, pro rata; and

(c) to the Class A-13 Certificates; and

(B) approximately [_____]%, sequentially, as follows:

(i) to the Class A-3 and Class A-15 Certificates, pro rata, up to the Priority Amount for such Distribution Date;

(ii) concurrently, to the Class A-1 and Class A-2 Certificates, pro rata;

(iii) to the Class A-4 Certificates; and

(iv) concurrently, to the Class A-3 and Class A-15 Certificates, pro rata.

The "PAC I Group Principal Amount" for any Distribution Date means the amount, if any, that would reduce the sum of the Principal Balances of the Class A-10, Class A-11, Class A-12, Class A-13 and Class A-14 Certificates (the "PAC I Group" or "PAC I Certificates") to the percentage of the sum of the initial Principal Balances of the PAC I Group shown in the related table appearing in Appendix F with respect to such Distribution Date.

The "PAC II Group Principal Amount" for any Distribution Date means the amount, if any, that would reduce the sum of the Principal Balances of the Class A-5, Class A-6 and Class A-7 Certificates (the "PAC II Group" or "PAC II Certificates" and, together with the PAC I Group or PAC I Certificates, the "PAC Groups" or "PAC Certificates") to the percentage of the sum of the initial Principal Balances of the PAC II Group shown in the related table appearing in Appendix F with respect to such Distribution Date.

The PAC I Group Principal Amount and PAC II Group Principal Amount are each also referred to as a "PAC Principal Amount".

The "Priority Amount" for any Distribution Date means the lesser of (i) the sum of the Principal Balances of the Class A-3 and Class A-15 Certificates and (ii) the sum of (A) the product of (1) the Priority Percentage, (2) the Shift Percentage and (3) approximately [_____]% of the Scheduled Principal Amount and (B) the product of (1) the Priority Percentage, (2) the Prepayment Shift Percentage and (3) approximately [_____]% of the Unscheduled Principal Amount.

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The "Priority Percentage" means the sum of the Principal Balances of the Class A-3 and Class A-15 Certificates divided by the sum of the Principal Balances of the Class A-1, Class A-2, Class A-3, Class A-4 and Class A-15 Certificates.

The "Scheduled Principal Amount" means the sum for each outstanding Mortgage Loan (including each defaulted Mortgage Loan with respect to which the related Mortgaged Property has been acquired by the Trust Estate) of the product of (A) the Non-PO Fraction for such Mortgage Loan and (B) the sum of the amounts for such Mortgage Loan described in clauses B(i) and B(iv) of the definition of "Class A Non-PO Optimal Principal Amount" beginning on page S-34.

The "Unscheduled Principal Amount" means the sum for each outstanding Mortgage Loan (including each defaulted Mortgage Loan with respect to which the related Mortgage Property has been acquired by the Trust Estate) of the product of (A) the Non-PO Fraction for such Mortgage Loan and (B) the sum of the amounts for such Mortgage Loan described in clauses B(ii) and B(iii) of the definition of "Class A Non-PO Optimal Principal Amount" beginning on page S-34.

The "Shift Percentage" for any Distribution Date will be the percentage indicated below:

                                   Shift
Distribution Date Occurring In   Percentage
------------------------------   ----------
                                          %
                                          %

The "Prepayment Shift Percentage" for any Distribution Date will be the percentage indicated below:

                                 Prepayment
                                   Shift
Distribution Date Occurring In   Percentage
------------------------------   ----------
                                          %
                                          %
                                          %
                                          %
                                          %
                                          %

Notwithstanding the foregoing, on each Distribution Date occurring on or after the Subordination Depletion Date, the Class A Non-PO Principal Distribution Amount will be distributed among the Classes of Class A Non-PO Certificates pro rata in accordance with their respective outstanding Principal Balances without regard to either the proportions or the priorities set forth above.

Any amounts distributed on a Distribution Date to the holders of any Class in reduction of Principal Balance will be allocated among the holders of such Class pro rata in accordance with their respective Percentage Interests.

Principal Payment Characteristics of the PAC Certificates and the Companion Certificates

The percentages of the initial aggregate Principal Balances of the PAC Groups set forth in the tables appearing in Appendix F were calculated using, among other things, the Structuring Assumptions. Based on such assumptions, the aggregate Principal Balances of the PAC I Group and PAC II Group would be reduced to the percentages of their initial aggregate Principal Balances indicated in such tables for each Distribution Date if prepayments on the Mortgage Loans occur at a constant rate between approximately [_____]% SPA (as defined herein under "Prepayment and Yield Considerations") and approximately
[_____]% SPA for the PAC I Group and between approximately [_____]% SPA (as defined herein under "Prepayment and Yield Considerations") and approximately
[_____]% SPA for the PAC II Group. However, it is highly unlikely that principal prepayments on the Mortgage Loans will occur at any constant rate or that the Mortgage Loans will prepay at the same rate. In addition, even if principal prepayments were to occur at a constant rate, there will be differences between the characteristics of the mortgage loans ultimately included in the Trust Estate and the characteristics which are assumed for the Structuring Assumptions. Therefore, there can be no assurance that the aggregate Principal Balances of the PAC Groups, after the application of the distributions to be made on any Distribution Date, will be equal to the percentages of the initial aggregate Principal Balances for such Distribution Dates specified in such tables.

S-38

The Weighted Average Lives of the Classes of PAC Certificates will vary under different prepayment scenarios. To the extent that principal prepayments occur at a constant rate that is slower than approximately[_____]% SPA for the PAC I Group and approximately [_____]% SPA for the PAC II Group, the available portion of Class A Non-PO Principal Distribution Amount on each Distribution Date may be insufficient to make distributions in reduction of the aggregate Principal Balances of one or both the PAC Groups in an amount that would reduce their aggregate Principal Balances to their planned Principal Balances for such Distribution Date. The Weighted Average Lives of the Classes of PAC Certificates may therefore be extended as illustrated for the PAC Certificates by the related tables appearing in Appendix C. To the extent that such principal prepayments occur at a constant rate that is faster than approximately [_____]% SPA for the PAC I Group and approximately [_____]% SPA for the PAC II Group, the Weighted Average Lives of the Classes of PAC Certificates may be shortened as illustrated for the PAC Certificates by the related tables appearing in Appendix C.

Because any Excess Principal Payments (as defined below) for any Distribution Date will be distributed to Certificateholders on such Distribution Date, the ability to distribute the PAC Principal Amounts on any Distribution Date will not be enhanced by the averaging of high and low principal prepayment rates on the Mortgage Loans over several Distribution Dates, as might be the case if any such Excess Principal Payments were held for future applications and not distributed monthly. There is no assurance that, with respect to distributions of the Class A Non-PO Principal Distribution Amount, the aggregate Principal Balances of the PAC Groups will not be reduced to zero significantly earlier or significantly later than the last Distribution Date shown in the tables appearing in Appendix F.

The extent to which the planned Principal Balance of a PAC Group will be achieved and the sensitivity of a PAC Group to principal prepayments on the Mortgage Loans will depend, in part, upon the period of time during which the Certificates supporting such PAC Group remain outstanding. The Companion Certificates and the PAC II Group support the PAC I Group and the Companion Certificates support the PAC II Group. On each Distribution Date, the excess of the portion of the Class A Non-PO Principal Distribution Amount available to make distributions of principal to a PAC Group over the PAC Principal Amount for such PAC Group (the "Excess Principal Payments") for such Distribution Date will be distributed to the Certificates supporting such PAC Group before being distributed to such PAC Group. This is intended to decrease the likelihood that the aggregate Principal Balance of a PAC Group will be reduced below its planned Principal Balance on a given Distribution Date. However, under certain relatively fast prepayment scenarios, one or more Classes of PAC Certificates of a PAC Group may continue to be outstanding when the Certificates supporting such PAC Group are no longer outstanding. Under such circumstances, principal payments will be applied to such PAC Group without regard to its PAC Principal Amount for a given Distribution Date. Thus, when the aggregate Principal Balance of the Certificates supporting a PAC Group has been reduced to zero, such PAC Group, if outstanding, will, in accordance with the priorities set forth above, become more sensitive to the rate of prepayment on the Mortgage Loans. Under such circumstances, such PAC Group will receive principal payments that otherwise would have been distributable to the Certificates supporting such PAC Group. Conversely, under certain relatively slow prepayment scenarios, the portion of the Class A Non-PO Principal Distribution Amount available to make distributions of principal to a PAC Group may not be sufficient to pay the PAC Principal Amount for such PAC Group on a given Distribution Date. In such cases, the portion of the Class A Non-PO Principal Distribution Amount available to make distributions of principal to such PAC Group for each subsequent Distribution Date will be applied in accordance with the priorities described herein such that the Certificates supporting such PAC Group will not receive distributions in reduction of their Principal Balances until the outstanding aggregate Principal Balance of such PAC Group has reached its planned Principal Balance for such Distribution Date. As a result, the Weighted Average Lives of the Classes of PAC Certificates may be extended if their PAC Group did not receive its PAC Principal Amount on a Distribution Date.

Classes of PAC Certificates are designed to provide some protection against volatility in their Weighted Average Lives. However, investors in the PAC Certificates should be aware that under certain prepayment scenarios, a "whipsaw" effect in the Weighted Average Lives of such Certificates could occur such that the Weighted Average Lives of such Certificates could extend, rather than shorten as prepayment rates increase (or shorten, rather than extend as prepayment rates decrease) and that any such phenomena will not necessarily be illustrated by the tables appearing in Appendix C.

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The Weighted Average Lives of the Companion Certificates will be particularly sensitive to the rate of prepayments on the Mortgage Loans. See "Prepayment and Yield Considerations" herein.

Additional Rights of the Residual Certificateholders

The Residual Certificates will remain outstanding for as long as the Trust Estate shall exist, whether or not such Class is receiving current distributions of principal or interest. The holders of the Residual Certificates will be entitled to receive the proceeds of the remaining assets of the REMIC, if any, on the final Distribution Date for the Certificates, after distributions in respect of any accrued but unpaid interest on the Certificates and after distributions in reduction of Principal Balance have reduced the Principal Balances of the Certificates to zero. It is not anticipated that there will be any material assets remaining in the Trust Estate on the final Distribution Date following the distributions of interest and in reduction of Principal Balance made on the Certificates on such date.

In addition, the Class A-R Certificateholders will be entitled on each Distribution Date to receive any Pool Distribution Amount remaining after all distributions pursuant to the Pool Distribution Amount Allocation have been made. It is not anticipated that there will be any material undistributed portion of the Pool Distribution Amount.

Restrictions on Transfer of the Residual Certificates

The Residual Certificates will be subject to restrictions on transfer and the Residual Certificates will contain a legend describing such restrictions.

Tax-related restrictions on transfer are discussed under "Material Federal Income Tax Consequences -- Federal Income Tax Consequences for REMIC Certificates -- Taxation of Residual Certificates -- Tax-Related Restrictions on Transfer of Residual Certificates" in the prospectus.

In addition, the Residual Certificates may not be purchased by or transferred to any person which is an employee benefit plan or other retirement plan or arrangement subject to Title I of the Employee Retirement Income Security Act of 1974, as amended ("ERISA") or Section 4975 of the Internal Revenue Code of 1986, as amended (the "Code") (any such plan or arrangement, an "ERISA Plan") or which is a governmental plan, as defined in Section 3(32) of ERISA, subject to any federal, state or local law ("Similar Law") which is, to a material extent, similar to the foregoing provisions of ERISA or the Code (collectively, with an ERISA Plan, a "Plan"), or any person acting on behalf of or investing the assets of such Plan. See "ERISA Considerations" herein and in the prospectus.

Periodic Advances

Generally, each Servicer is required to advance delinquent payments of principal and interest on any Mortgage Loan in the Trust Estate to the extent that such Servicer believes that such amounts will be recoverable by it from liquidation proceeds or other recoveries in respect of the related Mortgage Loan (each, a "Periodic Advance"). Upon a Servicer's failure to make a Periodic Advance required by the applicable Underlying Servicing Agreement, the Trustee, if such Servicer is Wells Fargo Bank, or the Master Servicer, if such Servicer is not Wells Fargo Bank, will be required to make such Periodic Advance.

Amounts advanced are reimbursable to the Servicer, the Master Servicer or the Trustee, as applicable, from amounts received on the related Mortgage Loan or from other funds in the Trust Estate if it is determined that the amounts advanced will not be recoverable from amounts received on such Mortgage Loan. See "Servicing of the Mortgage Loans -- Periodic Advances and Limitations Thereon" in the prospectus.

Subordination of Class B Certificates

The rights of the holders of the Class B Certificates to receive distributions with respect to the Mortgage Loans in the Trust Estate will be subordinated to such rights of the holders of the Class A Certificates and the rights of the holders of the Classes of Class B Certificates with higher numerical designations to receive distributions with respect to the Mortgage Loans in the Trust Estate will be subordinated to such rights of the holders of Classes of Class B Certificates with lower numerical designations, all to the extent described below. This subordination is

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intended to enhance the likelihood of timely receipt by the holders of the more senior Certificates of the full amount of their scheduled monthly payments of interest and principal and to afford the holders of the more senior Certificates protection against Realized Losses, as more fully described below. If Realized Losses exceed the credit support provided through subordination to a given Class of Certificates, all or a portion of such losses will be borne by such Class of Certificates.

The protection afforded to more senior Classes of Certificates by means of the subordination feature will be accomplished by the preferential right of such Classes to receive, prior to any distribution being made on a Distribution Date in respect of the more junior Classes of Certificates, the amounts of principal and interest due such Classes on each Distribution Date out of the Pool Distribution Amount with respect to such date and, if necessary, by the right of such Classes to receive future distributions on the Mortgage Loans that would otherwise have been payable to the more junior Classes of Certificates. Because of the priorities in distributing principal to the Class A Non-PO Certificates, some Classes of Class A Non-PO Certificates may be outstanding longer than other Classes of Class A Non-PO Certificates. The aggregate Principal Balance of the Class B Certificates will be reduced on each Distribution Date either through principal distributions or the allocation of Realized Losses. The longer a Class of Class A Non-PO Certificates is outstanding, the smaller the Principal Balances will be of the Class B Certificates providing subordination for such Class A Certificates.

Amounts distributed to holders of Subordinated Certificates will not be available to cover delinquencies or Realized Losses in respect of subsequent Distribution Dates.

Allocation of Losses

Realized Losses on the Mortgage Loans will not be allocated to the holders of the Class A Certificates until the date on which the aggregate Principal Balance of the Subordinated Certificates has been reduced to zero (the "Subordination Depletion Date"). Prior to such time, such Realized Losses will be allocated to the Classes of Class B Certificates sequentially in reverse numerical order, until the Principal Balance of each such Class has been reduced to zero.

The allocation of the principal portion of a Realized Loss (other than a Debt Service Reduction) of a Mortgage Loan will be effected through the adjustment of the Principal Balance of the most subordinate Class then outstanding in such amount as is necessary to cause the Aggregate Principal Balance to equal the Adjusted Pool Amount.

Allocations to the Classes of Class B Certificates of (i) the principal portion of Debt Service Reductions, (ii) the interest portion of Realized Losses, (iii) any shortfalls resulting from delinquencies for which the Servicer, the Master Servicer or the Trustee does not advance and (iv) any interest shortfalls resulting from the timing of the receipt of Unscheduled Principal Receipts (other than Prepayments in Full and Curtailments) with respect to Mortgage Loans will result from the priority of distributions of the Pool Distribution Amount first to the Class A Certificates and then to the Classes of Class B Certificates in numerical order as described above under "--Distributions."

After distributions of principal have been made on a Distribution Date, the allocation of the principal portion of Realized Losses in respect of the Mortgage Loans allocated on or after the Subordination Depletion Date will be effected through the adjustment of the Class A Non-PO Principal Balance and the Principal Balance of the Class A-PO Certificates such that (i) the Class A Non-PO Principal Balance equals the Adjusted Pool Amount (Non-PO Portion) and
(ii) the Principal Balance of the Class A-PO Certificates equals the Adjusted Pool Amount (PO Portion). The principal portion of such Realized Losses allocated to the Class A Non-PO Certificates will be allocated to such outstanding Classes of Class A Non-PO Certificates, pro rata, in accordance with their Principal Balances or, in the case of a Class of Accrual Certificates, its initial Principal Balance, if lower. The interest portion of any Realized Loss allocated on or after the Subordination Depletion Date will be allocated among the outstanding Classes of Class A Non-PO Certificates, pro rata, in accordance with their respective Interest Accrual Amounts, without regard to any reduction pursuant to this sentence. Any such losses will be allocated among the outstanding Class A Non-PO Certificates of each such Class pro rata in accordance with their respective Percentage Interests.

On or after the Subordination Depletion Date, the Principal Balance of a Class of Super Senior Support Certificates will be reduced not only by the principal portion of Realized Losses allocated to such Class as provided

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in the preceding paragraph but also by the portion allocated to the related Class of Super Senior Certificates indicated in the table below.

The related Classes of Super Senior and Super Senior Support Certificates are as follows:

Super Senior   Super Senior Support
  Classes            Classes
------------   --------------------
 Class A-3          Class A-15
 Class A-12         Class A-14

If due to losses on the Mortgage Loans, the Pool Distribution Amount is not sufficient to cover the Class A Non-PO Optimal Principal Amount on a particular Distribution Date, then the Class A Percentage on and after the next Distribution Date will be proportionately increased, thereby reducing, as a relative matter, the respective interest of the Class B Certificates in future payments of principal on the Mortgage Loans.

Notwithstanding the foregoing, the provisions relating to subordination will not be applicable in connection with a Bankruptcy Loss so long as the applicable Servicer has notified the Trustee and the Master Servicer in writing that such Servicer is diligently pursuing any remedies that may exist in connection with the representations and warranties made regarding the related Mortgage Loan and when (A) the related Mortgage Loan is not in default with regard to the payments due thereunder or (B) delinquent payments of principal and interest under the related Mortgage Loan and any premiums on any applicable Standard Hazard Insurance Policy and any related escrow payments in respect of such Mortgage Loan are being advanced on a current basis by such Servicer, in either case without giving effect to any Debt Service Reduction.

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DESCRIPTION OF THE MORTGAGE LOANS(1)

General

The mortgage loans to be included in the Trust Estate will be fixed interest rate, monthly pay, fully amortizing, one- to four-family residential first mortgage loans (the "Mortgage Loans"). Substantially all of the Mortgage Loans will have original terms to stated maturity of approximately 30 years. The Mortgage Loans will be secured by first liens (the "Mortgages") on one- to four-family residential properties (the "Mortgaged Properties") and will have the additional characteristics described herein and in the prospectus.

Each of the Mortgage Loans is subject to a due-on-sale clause. See "Certain Legal Aspects of the Mortgage Loans-- Due-on-Sale' Clauses" and "Servicing of the Mortgage Loans--Enforcement of Due-on-Sale Clauses; Realization Upon Defaulted Mortgage Loans" in the prospectus.

The Mortgage Loans were selected by the Sponsor from the Sponsor's first lien, fixed-rate mortgage loans, and were chosen to conform to the characteristics of mortgage loans eligible to be securitized in the Depositor's WFALT securitization program. See "The Sponsor" in the prospectus.

Mortgage Loan Data Appearing in Appendix A

The Mortgage Loans were originated by Wells Fargo Bank or its affiliates or purchased from other mortgage lenders.

[Any originator or group of affiliated originators, apart from the Sponsor or its affiliates, that originated or is expected to originate 10% or more of the mortgage pool will be identified. For any originator or group of affiliated originators, apart from the Sponsor or its affiliates, that originated or is expected to originate 20% or more of the mortgage pool, the following information will be provided: (1) originator's form of organization and (2) to the extent material, a description of the originator's origination program and how long the originator has been engaged in originating assets, including a discussion of the originator's experience in originating assets of the type included in this transaction.]

In originating Mortgage Loans, the documentation levels vary depending upon several factors, including loan amount, Loan-to-Value Ratio and the type and purpose of the Mortgage Loan. Documentation levels include "full documentation," "stated," "no documentation" and "no ratio." Asset and income verifications were obtained for Mortgage Loans processed with "full documentation." In the case of "stated" loans, borrowers stated their income, source of income and asset levels. In such cases, assets have also been verified if that option was selected via a risk model assessment or by the borrower. In the case of "no documentation" loans, borrowers did not provide any information regarding their income, their source of income or their asset levels. In the case of "no ratio" loans, income was not disclosed by the borrower, however the source of income and the source and amount of assets were stated. In such cases, assets have also been verified if that option was chosen. In some instances, a verification of the borrower's employment may have been obtained. However, for all of the Mortgage Loans, a credit report on the borrower and a property appraisal were obtained. For a description of the documentation programs, see "The Sponsor's Mortgage Loan Programs" in the prospectus.


(1) The descriptions in this prospectus supplement of the Trust Estate and the properties securing the Mortgage Loans to be included in the Trust Estate are based upon the expected characteristics of the Mortgage Loans at the close of business on the Cut-Off Date, as adjusted for the scheduled principal payments due on or before such date. Notwithstanding the foregoing, any of such Mortgage Loans may be excluded from the Trust Estate (i) as a result of principal prepayment thereof in full or (ii) if, as a result of delinquencies or otherwise, the Depositor otherwise deems such exclusion necessary or desirable. In either event, other Mortgage Loans may be included in the Trust Estate. The Depositor believes that the information set forth herein with respect to the expected characteristics of the Mortgage Loans on the Cut-Off Date is representative of the characteristics as of the Cut-Off Date of the Mortgage Loans to be included in the Trust Estate as it will be constituted at the time the Certificates are issued, although the aggregate principal balance of the Mortgage Loans included in the Trust Estate as of the Cut-Off Date, the range of Mortgage Interest Rates and maturities, and certain other characteristics of the Mortgage Loans in the Trust Estate may vary. In the event that any of the material characteristics as of the Cut-Off Date of the Mortgage Loans that constitute the Trust Estate on the date of initial issuance of the Certificates vary by 5% or more (other than as a result of scheduled payment or prepayment of the Mortgage Loans) the Depositor will file a Current Report on Form 8-K containing updated information with the Securities and Exchange Commission.

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The Mortgage Loans were originated for various purposes. In general, in the case of a Mortgage Loan made for "rate/term" refinance purposes, substantially all of the proceeds are used to pay in full the principal balance of a previous mortgage loan of the mortgagor with respect to a Mortgaged Property and to pay origination and closing costs associated with such refinancing. However, in the case of a Mortgage Loan made for "equity take out" refinance purpose, all or a portion of the proceeds are generally required by the mortgagor for uses unrelated to the Mortgaged Property. The amount of such proceeds retained by the mortgagor may be substantial.

The Mortgage Loans were originated through various channels. Mortgage Loans originated through Wells Fargo Bank's retail channel may include Mortgage Loans originated directly by Wells Fargo Bank (including originations through Wells Fargo Bank's Private Mortgage Banking division and Joint Ventures). See "The Sponsor's Mortgage Loan Programs--Mortgage Loan Production Sources" in the prospectus. Mortgage Loans originated through the correspondent channel are Mortgage Loans meeting certain qualifications acquired from unaffiliated originators. See "The Sponsor's Mortgage Loan Programs--Acquisition of Mortgage Loans from Correspondents" in the prospectus. Mortgage Loans originated through the wholesale channel include referrals from mortgage brokers and similar entities. See "The Sponsor's Mortgage Loan Programs--Mortgage Loan Production Sources" in the prospectus.

The first table appearing in Appendix A sets forth certain characteristics of the Mortgage Loans, the Premium Mortgage Loans and the Discount Mortgage Loans.

For purposes of Appendix A, the term "single-family dwellings" includes single family attached planned unit developments ("PUDs"), single family detached PUDs, single family townhouses and single family detached dwellings.

In addition, for purposes of Appendix A, the Loan-to-Value Ratio of a Mortgage Loan is calculated using the lesser of (i) the appraised value of the related Mortgaged Property, as established by an appraisal obtained by the originator from an appraiser generally no more than four months prior to origination (subject to exceptions set forth under "The Sponsor's Mortgage Loan Programs--Mortgage Loan Underwriting--General Standards" in the prospectus) and
(ii) the sale price for such property. For the purpose of calculating the Loan-to-Value Ratio of any Mortgage Loan that is the result of the refinancing (including a refinancing for "equity take out" purposes) of an existing mortgage loan, the appraised value of the related Mortgaged Property is generally determined by reference to an appraisal. Although for purposes of applying the Underwriting Standards, the Loan-to-Value Ratio of an LOC Pledged Asset Mortgage Loan, if any, is calculated taking into account the value of the LOC, for purposes of this prospectus supplement, such Loan-to-Value Ratio is calculated without regard to the value of such LOC. See "The Trust Estates -- Mortgage Loans -- Pledged Asset Mortgage Loans" in the prospectus. There can be no assurance that such appraisal, which is based on the independent judgment of an appraiser and not an arms-length sales transaction, is an accurate representation of the market value of a Mortgaged Property. See "The Trust Estates -- Mortgage Loans" in the prospectus. No assurance can be given that the values of the Mortgaged Properties securing the Mortgage Loans have remained or will remain at the levels used in calculating the Loan-to-Value Ratios shown in Appendix A. The Depositor has taken no action to establish the current value of any Mortgaged Property. See "Risk Factors -- Real Estate Market Conditions Affect Mortgage Loan Performance" and "-- Geographic Concentration May Increase Rates of Loss and Delinquency" in the prospectus.

For purposes of Appendix A, the "Combined Loan-to-Value Ratio" or "CLTV" is the ratio, expressed as a percentage, of (i) the principal amount of the Mortgage Loan at origination plus (a) any junior mortgage encumbering the related Mortgaged Property originated by the Sponsor or of which the Sponsor has knowledge at the time of the origination of the Mortgage Loan or (b) the total available amount of any home equity line of credit originated by the Sponsor or of which the Sponsor has knowledge at the time of the origination of the Mortgage Loan, over (ii) the lesser of (a) the appraised value of the related Mortgaged Property at origination or (b) the sales price for such property. There can be no assurance that all data regarding junior mortgage loans or home equity lines of credit originated by parties other than the Sponsor is known by the Sponsor and therefore accurately reflected in the table appearing in Appendix A.

Mortgage Loans with Loan-to-Value Ratios at origination greater than 80% may or may not be covered by a primary mortgage insurance policy. Certain Mortgage Loans may be covered by lender-paid primary mortgage insurance policies (each, an "LPMI Policy") or borrower-paid primary mortgage insurance policies (each, a "BPMI Policy"). The LPMI Policies and BPMI Policies will be assigned to the Trust on the Closing Date. The Sponsor

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will be responsible for paying the premiums under the LPMI Policies and may assign such obligation only with the consent of each Rating Agency and the respective primary mortgage insurance policy provider. Information with respect to the Mortgage Loans covered by LPMI Policies and BPMI Policies is set forth in Appendix A.

Appendix A also contains a table of the FICO Scores for the Mortgage Loans. "FICO Scores" are statistical credit scores obtained by many mortgage lenders in connection with the loan application to help assess a borrower's credit-worthiness. FICO Scores are generated by models developed by a third party and are made available to lenders through three national credit bureaus. The models were derived by analyzing data on consumers in order to establish patterns which are believed to be indicative of the borrower's probability of default. The FICO Score is based on a borrower's historical credit data, including, among other things, payment history, delinquencies on accounts, levels of outstanding indebtedness, length of credit history, types of credit, and bankruptcy experience. FICO Scores range from approximately 300 to approximately 850, with higher scores indicating an individual with a more favorable credit history compared to an individual with a lower score. However, a FICO Score purports only to be a measurement of the relative degree of risk a borrower represents to a lender, i.e., that a borrower with a higher score is statistically expected to be less likely to default in payment than a borrower with a lower score. In addition, it should be noted that FICO Scores were developed to indicate a level of default probability over a two-year period which does not correspond to the life of a mortgage loan. Furthermore, FICO Scores were not developed specifically for use in connection with mortgage loans, but for consumer loans in general. Therefore, a FICO Score does not take into consideration the effect of mortgage loan characteristics on the probability of repayment by the borrower. The FICO Scores set forth in the tables appearing in Appendix A entitled Original FICO Scores (the "Original FICO Scores") were obtained at either the time of origination of the Mortgage Loans or more recently. Neither the Depositor nor the Sponsor makes any representations or warranties as to any borrower's current FICO Score, the actual performance of any Mortgage Loan or that a particular FICO Score should be relied upon as a basis for an expectation that the borrower will repay the Mortgage Loan according to its terms.

For purposes of Appendix A, "Original Total Debt-to-Income Ratio" is the ratio, expressed as a percentage, of (i) the amount of the monthly debt obligations (including the proposed new housing payment and related expenses such as, but not limited to, property taxes and insurance) over (ii) the mortgagor's gross monthly income, as of the origination of the Mortgage Loan.

For purposes of the table in Appendix A setting forth historical delinquency data with respect to the Mortgage Loans in the mortgage pool, the table shows the extent to which any Mortgage Loans, since their origination (or a period of three years, if shorter), have ever been delinquent and whether foreclosure proceedings with respect to the Mortgage Loans or bankruptcy proceedings with respect to the mortgagors of the Mortgage Loans have ever been instituted. Mortgage Loans are categorized in the most severe category they fall into for any time period, with "Ever 30-59 Days" being the least severe category and "Ever Bankruptcy" being the most severe category. Mortgage Loans are only reported in one category for any time period. The indicated categories of delinquency are based on the number of days delinquent. A mortgage was considered delinquent if a payment was not received by the end of the month in which such payment was due.

The data appearing in Appendix A may not be exact due to rounding.

See "The Sponsor's Mortgage Loan Programs--Mortgage Loan Underwriting" in the prospectus.

Mortgage Loan Underwriting

The Mortgage Loans were generally originated in conformity with the underwriting standards described in the prospectus under the heading "The Sponsor's Mortgage Loan Programs -- Mortgage Loan Underwriting -- Alt-A Mortgage Loans" (the "Underwriting Standards"). In certain instances, exceptions to the Underwriting Standards may have been granted by Wells Fargo Bank.

[To the extent that a transaction contains Mortgage Loans for which exceptions to Underwriting Standards were granted and the Sponsor concludes that such exceptions would be material to investors in the related Certificates, such exceptions to the Underwriting Standards will be described in the applicable prospectus supplement.]

See "The Sponsor's Mortgage Loan Programs -- Mortgage Loan Underwriting" and "--Acquisition of Mortgage Loans from Correspondents" in the prospectus.

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Mandatory Repurchase or Substitution of Mortgage Loans

The Depositor is required, with respect to Mortgage Loans that are found by the Custodian to have defective documentation, or in respect of which the Depositor has breached a representation or warranty which materially adversely affects Certificateholders, either to repurchase such Mortgage Loans or, at the Depositor's option, if within two years of the date of initial issuance of the Certificates, to substitute new Mortgage Loans therefor. See "Prepayment and Yield Considerations" herein and "The Pooling and Servicing Agreement -- Assignment of Mortgage Loans to the Trustee" in the prospectus.

Optional Purchase of Mortgage Loans

Under certain circumstances as described in the prospectus under "The Pooling and Servicing Agreement -- Optional Purchases" the Depositor may, at its sole discretion purchase certain Mortgage Loans from the Trust Estate. See "Prepayment and Yield Considerations" herein.

[DESCRIPTION OF THE MORTGAGE CERTIFICATES]

[For any prospectus supplement relating to a Trust Fund containing Mortgage Certificates, disclosure regarding the Mortgage Certificates will be included.]

PREPAYMENT AND YIELD CONSIDERATIONS

General

The rate of distributions of principal to any Class of the Offered Certificates, the aggregate amount of distributions on any Class of the Offered Certificates and the Weighted Average Life and yield to maturity of any Class of the Offered Certificates purchased at a discount or premium will be directly related to the rate of payments of principal on the applicable Mortgage Loans and the amount and timing of mortgagor defaults resulting in Realized Losses on such Mortgage Loans. Prepayments (which, as used herein, include all unscheduled payments of principal, including payments as the result of liquidations, purchases and repurchases) of the Mortgage Loans will result in distributions to Certificateholders then entitled to distributions in respect of principal in respect of such Mortgage Loans of amounts which would otherwise be distributed over the remaining terms of such Mortgage Loans. Since the rate of prepayment on the Mortgage Loans will depend on future events and a variety of factors (as described more fully below and in the prospectus under "Prepayment and Yield Considerations"), no assurance can be given as to such rate or the rate of principal payments or yield on, or Weighted Average Life of, any Class of the Offered Certificates or the aggregate amount of distributions on any Class of the Offered Certificates.

The rate of principal payments on the Mortgage Loans will be affected by the amortization schedules of the Mortgage Loans, the rate of principal prepayments (including partial prepayments and those resulting from refinancing) thereon by mortgagors, liquidations of defaulted Mortgage Loans, repurchases by the Depositor of Mortgage Loans as a result of defective documentation or breaches of representations and warranties and optional purchases by the Depositor of all of the Mortgage Loans in connection with the termination of the Trust Estate. See "Description of the Mortgage Loans--Mandatory Repurchase or Substitution of Mortgage Loans" herein and "The Pooling and Servicing Agreement--Assignment of Mortgage Loans to the Trustee," "--Optional Purchases" and "--Termination; Optional Purchase of Mortgage Loans" in the prospectus. Mortgagors are permitted to prepay the Mortgage Loans, in whole or in part, at any time without penalty. If prevailing rates for similar mortgage loans fall below the Mortgage Interest Rates on the Mortgage Loans, the rate of prepayment would generally be expected to increase. Conversely, if interest rates on similar mortgage loans rise above the Mortgage Interest Rates on the Mortgage Loans, the rate of prepayment would generally be expected to decrease. The rate of prepayment on the Mortgage Loans may also be influenced by programs offered by mortgage loan originators (including Wells Fargo Bank), servicers (including Wells Fargo Bank) and mortgage loan brokers to encourage refinancing through such originators, servicers and brokers, including, but not limited to, general or targeted solicitations (which may be based on characteristics including, but not limited to, the mortgage loan interest rate or payment history and the geographic location of the Mortgaged Property), reduced origination fees or closing costs, pre-approved applications, waiver of pre-closing interest accrued with respect to a refinanced loan prior to the pay-off of such

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loan, or other financial incentives. In particular, the application of Wells Fargo Bank's "retention program," which enables qualifying mortgagors to refinance at greatly reduced cost, to its servicing portfolio may substantially affect the rate of prepayment on the Mortgage Loans. See "Prepayment and Yield Considerations--Refinancings" in the prospectus. In addition, the Sponsor or third parties may enter into agreements with borrowers providing for the bi-weekly payment of principal and interest on the related mortgage loan, thereby accelerating payment of the mortgage loan resulting in partial prepayments.

For further information regarding historical delinquency, cumulative loss and prepayment experience of the Sponsor's prior residential mortgage loan securitizations, see "Static Pool Information" in this prospectus supplement. As a result of certain Mortgage Loans being originated using underwriting standards that, in certain respects, may be less stringent than the general standards applied by the Sponsor, such Mortgage Loans may experience rates of delinquency and cumulative loss that are higher than those experienced by mortgage loans that satisfy the general standards applied by the Sponsor.

Other factors affecting prepayment of mortgage loans include changes in mortgagors' housing needs, job transfers, unemployment or substantial fluctuations in income, significant fluctuations in real estate values and adverse economic conditions either generally or in particular geographic areas, mortgagors' equity in the Mortgaged Properties, including the use of the properties as second or vacation homes, and servicing decisions, such as, without limitation, the decision as to whether to foreclose on a Mortgage Loan or to modify the terms of the related Mortgage Note and decisions as to the timing of any foreclosure. Furthermore, certain characteristics of mortgage loans may be more likely to affect prepayments. These characteristics include, but are not limited to, principal balance, loan-to-value ratio, borrower credit quality and current interest rate higher than prevailing interest rates. No representation is made as to the rate of prepayment on the Mortgage Loans included in the Trust Estate having any particular characteristic. In addition, all of the Mortgage Loans contain due-on-sale clauses which will generally be exercised upon the sale of the related Mortgaged Properties. Consequently, acceleration of mortgage payments as a result of any such sale will affect the level of prepayments on the Mortgage Loans. The extent to which defaulted Mortgage Loans are assumed by transferees of the related Mortgaged Properties or are refinanced will also affect the rate of principal payments. The rate of prepayment and, therefore, the yield to maturity of the Offered Certificates will be affected by, among other things, the extent to which (i) the Depositor elects to repurchase, rather than substitute for, Mortgage Loans which are found by the Custodian to have defective documentation or with respect to which the Depositor has breached a representation or warranty, (ii) a substitute Mortgage Loan has an unpaid principal balance less than the Mortgage Loan for which it is substituted or (iii) a Servicer may take certain actions to mitigate losses on a defaulted Mortgage Loan which may include, but are not limited to, selling the Mortgaged Property of such Mortgage Loan for less than its unpaid principal balance or modifying the payment terms of such Mortgage Loan. See "Servicing of the Mortgage Loans -- Enforcement of Due-on-Sale Clauses; Realization Upon Defaulted Mortgage Loans" in the prospectus.

As described under "Description of the Certificates--Principal (Including Prepayments)," all or a disproportionate percentage of principal prepayments on the Mortgage Loans (including liquidations and repurchases of Mortgage Loans) will be distributed, to the extent of the applicable Non-PO Fraction, to the Class A Non-PO Certificates then entitled to distributions in respect of principal during the nine years beginning on the first Distribution Date, and, to the extent that such principal prepayments are made in respect of a Discount Mortgage Loan, to the Class A-PO Certificates in proportion to the interest of the Class A-PO Certificates in such Discount Mortgage Loan represented by the related PO Fraction.

As described herein under "Description of the Certificates--Principal (Including Prepayments)--Allocation of Amount to be Distributed on the Class A Certificates" unless the Principal Balances of the Class A-1, Class A-2 and Class A-4 Certificates have been reduced to zero, the Class A-3 and Class A-15 Certificates will not be entitled to any distributions of principal payments for
[____] years and thereafter the percentage of principal payments (including prepayments) allocated to the Class A-3 and Class A-15 Certificates will increase.

The yield to maturity of the Offered Certificates will be sensitive in varying degrees to the rate and timing of principal payments (including prepayments, which may be made at any time without penalty) on the Mortgage Loans. Investors in the Offered Certificates should consider the associated risks, including, in the case of Offered Certificates purchased at a discount, particularly the Principal Only Certificates, the risk that a slower than anticipated rate of payments in respect of principal (including prepayments) on the Mortgage Loans, or, in the case of the Principal Only Certificates, on the Discount Mortgage Loans, will have

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a negative effect on the yield to maturity of such Certificates and, in the case of Offered Certificates purchased at a premium, the risk that a faster than anticipated rate of payments in respect of principal (including prepayments) on the Mortgage Loans will have a negative effect on the yield to maturity of such Certificates. Investors purchasing Offered Certificates at a premium should also consider the risk that a rapid rate of payments in respect of principal (including prepayments) on the Mortgage Loans could result in the failure of such investors to fully recover their initial investments. An investor is urged to make an investment decision with respect to any Class of Offered Certificates based on the anticipated yield to maturity of such Class resulting from its purchase price and such investor's own determination as to anticipated Mortgage Loan principal payment rates under a variety of scenarios.

The timing of changes in the rate of prepayment on the Mortgage Loans may significantly affect the actual yield to maturity experienced by an investor who purchases an Offered Certificate at a price other than par, even if the average rate of principal payments experienced over time is consistent with such investor's expectation. In general, the earlier a prepayment of principal on the applicable Mortgage Loans, the greater the effect on such investor's yield to maturity. As a result, the effect on such investor's yield of principal payments occurring at a rate higher (or lower) than the rate anticipated by the investor during the period immediately following the issuance of the Offered Certificates would not be fully offset by a subsequent like reduction (or increase) in the rate of principal payments.

The yield to maturity on the Classes of Class B Certificates with higher numerical designations will generally be more sensitive to losses than the Classes with lower numerical designations because the entire amount of such losses will be allocable to the Classes of Class B Certificates in reverse numerical order, except as provided herein. To the extent not covered by Periodic Advances, delinquencies on Mortgage Loans will also have a relatively greater effect on the yield to maturity on the Classes of Class B Certificates with higher numerical designations because amounts otherwise distributable on the Class B Certificates will be made available to protect the Class A Certificates against interruptions in distributions due to such unadvanced mortgagor delinquencies. Such unadvanced delinquencies, even if subsequently cured, may affect the timing of the receipt of distributions on the Class B Certificates.

On and after the Subordination Depletion Date, the yield to maturity on a Class of Super Senior Support Certificates will be more sensitive to losses than the other Class A Non-PO Certificates because while they are outstanding each such Class of Super Senior Support Certificates will bear not only its share of losses but also the share allocated to the related Class of Super Senior Certificates. See "Description of the Certificates -- Allocation of Losses" herein.

The actual yield to maturity experienced by an investor may also be affected by the occurrence of interest shortfalls resulting from Unscheduled Principal Receipts to the extent, if any, that such interest shortfalls are not covered by Compensating Interest or subordination. See "Description of the Certificates -- Interest" herein and "Servicing of the Mortgage Loans -- Changes in Servicing" in the prospectus.

The yield to maturity on the Offered Certificates and more particularly on the Class B-1, Class B-2 and Class B-3 Certificates, may be affected by the geographic concentration of the Mortgaged Properties securing the applicable Mortgage Loans. Certain regions in the United States have experienced or may experience significant fluctuations in housing prices. In addition, certain regions have experienced or may experience natural disasters, including earthquakes, fires, floods, hurricanes and tornadoes, which may adversely affect property values. See "Description of the Mortgage Loans" herein. Any deterioration in housing prices in the regions in which there is a significant concentration of Mortgaged Properties, as well as other regions in which the Mortgaged Properties are located, and any deterioration of economic conditions in such regions which adversely affects the ability of borrowers to make payments on the Mortgage Loans, may increase the likelihood of losses on the Mortgage Loans. Such losses, if they occur, may have an adverse effect on the yield to maturity of the Offered Certificates and more particularly on the Class B-1, Class B-2 and Class B-3 Certificates.

As to Mortgaged Properties in regions that have recently experienced natural disasters, neither the Depositor nor the Sponsor has undertaken the physical inspection of such Mortgaged Properties. As a result, there can be no assurance that material damage to any Mortgaged Property in an affected region has not occurred. In the Pooling and Servicing Agreement, the Depositor will represent and warrant that, as of the date of issuance of the Certificates, each Mortgaged Property is undamaged by flood, water, fire, earthquake or earth movement, wind-storm, tornado or similar casualty (excluding casualty from the presence of hazardous wastes or hazardous substances, as to which the

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Depositor makes no representation) in a manner which would adversely affect the value of such Mortgaged Property as security for such Mortgage Loan or the use for which such premises was intended. In the event of a breach of such representation with respect to a Mortgaged Property which materially and adversely affects the interests of Certificateholders in the related Mortgage Loan, the Depositor will be obligated to repurchase or substitute for such Mortgage Loan, as described under "The Pooling and Servicing Agreement--Assignment of Mortgage Loans to the Trustee" and "--Representations and Warranties" in the prospectus. Repurchase of any such Mortgage Loan will affect in varying degrees the yields and Weighted Average Lives of the related Classes of Offered Certificates and could adversely affect the yield of any related Offered Certificates purchased at a premium.

No representation is made as to the rate of principal payments on the Mortgage Loans or as to the yield to maturity of any Class of Offered Certificates.

An investor should consider the risk that rapid rates of prepayments on the applicable Mortgage Loans and therefore of amounts distributable in reduction of principal balance of the related Offered Certificates, may coincide with periods of low prevailing interest rates. During such periods, the effective interest rates on securities in which an investor may choose to reinvest amounts distributed in reduction of the principal balance of such investor's Offered Certificate may be lower than the applicable Pass-Through Rate or expected yield. Conversely, slower rates of prepayments on the Mortgage Loans and therefore of amounts distributable in reduction of principal balance of the related Offered Certificates, may coincide with periods of high prevailing interest rates. During such periods, the amount of principal distributions available to an investor for reinvestment at such high prevailing interest rates may be relatively small.

Investors in the Floating Rate Certificates should understand that if LIBOR is greater than or equal to [_____]% and [_____]% per annum, the Pass-Through Rates of the Class A-2 and Class A-5 Certificates, respectively, will remain at their maximum rates. Investors in the Floating Rate Certificates should also consider the risk that if LIBOR is lower than anticipated, the actual yields to such investors could be lower than anticipated yields. Conversely, investors in the Inverse Floating Rate Certificates should consider the risk that if LIBOR is higher than anticipated, the actual yields to such investors could be significantly lower than the anticipated yields. Investors in the Inverse Floating Rate Certificates should also understand that if LIBOR is greater than or equal to [_____]% and [_____]% per annum, the Class A-1 and Class A-6 Certificates, respectively, will accrue interest at their minimum rate.

In addition, there can be no assurance that LIBOR will correlate with the levels of prevailing mortgage interest rates, therefore it is possible that lower prevailing mortgage rates, which might be expected to result in faster prepayments, could occur concurrently with an increase in LIBOR. However, if, as generally expected, higher mortgage rates and, accordingly, lower prepayment rates, were to occur concurrently with an increase in LIBOR, the Pass-Through Rate of a Class of Inverse Floating Rate Certificates would be reduced at the same time that the rate of reduction of the Principal Balance of such Class may be reduced. In such circumstances, investors in the Inverse Floating Rate Certificates could have a significantly lower yielding instrument with a longer Weighted Average Life than anticipated. See "--Sensitivities of Certain Classes of Certificates" below.

Investors in the Floating Rate and Inverse Floating Rate Certificates should understand that the timing of changes in LIBOR may affect the actual yields to such investors even if the average rate of LIBOR is consistent with such investors' expectations. Each investor must make an independent decision as to the appropriate LIBOR assumptions to be used in deciding whether to purchase a Floating Rate or Inverse Floating Rate Certificate.

The Weighted Average Lives of the Companion Certificates will be particularly sensitive to the rate of prepayments on the Mortgage Loans. Specifically, on each Distribution Date up to and including the Distribution Date on which the Principal Balances of the Companion Certificates, which support the PAC Groups are reduced to zero and after the PAC Principal Amounts have been distributed for such Distribution Date, principal payments from the Class A Non-PO Principal Distribution Amount for such Distribution Date will be applied to the Companion Certificates before being distributed to such PAC Groups. Further, the Companion Certificates will not receive distributions in reduction of principal on such Distribution Date from the Class A Non-PO Principal Distribution Amount if the Class A Non-PO Principal Distribution Amount is not sufficient to pay the PAC Principal Amounts of the PAC Groups on such Distribution Date. See "Description of the Certificates--Principal (Including Prepayments)--Principal Payment Characteristics of the PAC Certificates and the Companion Certificates" herein.

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Classes of PAC Certificates are designed to provide some protection against volatility in their Weighted Average Lives. However, investors in the PAC Certificates should be aware that under certain prepayment scenarios, a "whipsaw" effect in the Weighted Average Lives of such Certificates could occur such that the Weighted Average Lives of such Certificates could extend, rather than shorten as prepayment rates increase (or shorten, rather than extend as prepayment rates decrease) and that any such phenomena will not necessarily be illustrated by the tables appearing in Appendix C.

Due to the special tax treatment of residual interests, the after-tax return of the Residual Certificates may be significantly lower than would be the case if the Residual Certificates were taxed as debt instruments, or may be negative. See "Federal Income Tax Considerations" herein.

As referred to herein, the "Weighted Average Life" of a Class of Offered Certificates refers to the average amount of time that will elapse from the date of issuance of such Class until each dollar in reduction of the Principal Balance of such Class is distributed to the investor.

Prepayments on mortgage loans are commonly measured relative to a prepayment standard or model. The model used in this prospectus supplement, the Standard Prepayment Assumption ("SPA"), represents an assumed rate of prepayment each month relative to the then-outstanding principal balance of a pool of new mortgage loans. A prepayment assumption of 100% SPA assumes constant prepayment rates of 0.2% per annum of the then-outstanding principal balance of such mortgage loans in the first month of the life of the mortgage loans and an additional 0.2% per annum in each month thereafter until the 30th month. Beginning in the 30th month and in each month thereafter during the life of the mortgage loans, 100% SPA assumes a constant prepayment rate of 6% per annum each month. As used in the tables appearing in the appendices, "0% SPA" assumes prepayment rates equal to 0% of SPA, i.e., no prepayments. Correspondingly, "[___]% SPA" assumes prepayment rates equal to [_____]% of SPA, and so forth. SPA does not purport to be an historical description of prepayment experience or prediction of the anticipated rate of prepayment of any pool of mortgage loans, including the Mortgage Loans.

Appendix C sets forth the decrement tables for the Offered Certificates. The tables appearing in Appendix C have been prepared assuming, among other things, the following (the "Structuring Assumptions"):

(i) the Trust Estate consists of the "Assumed Discount Mortgage Loans" and the "Assumed Premium Mortgage Loans" (collectively, the "Assumed Mortgage Loans") with the characteristics set forth in Appendix B of this prospectus supplement;

(ii) the scheduled payment in each month for each Assumed Mortgage Loan has been based on its outstanding balance as of the first day of the month preceding the month of such payment, its Mortgage Interest Rate and its remaining term to stated maturity, so that such scheduled payments would amortize the remaining balance over its remaining term to maturity;

(iii) scheduled monthly payments of principal and interest on the Assumed Mortgage Loans will be timely received on the first day of each month (with no defaults), commencing in [_____] 20 ;

(iv) the Depositor does not repurchase any of the Assumed Mortgage Loans and the Depositor does not exercise its option to purchase the Assumed Mortgage Loans and thereby cause a termination of the Trust Estate;

(v) principal payments on the Assumed Mortgage Loans representing principal prepayments in full of individual mortgage loans will be received on the last day of each month commencing in [_____] 20 at the respective constant percentages of SPA set forth in the tables and there are no Curtailments, Prepayment Interest Shortfalls or Relief Act Shortfalls;

(vi) the Certificates will be issued on the Closing Date;

(vii) distributions to Certificateholders will be made on the 25th day of each month, commencing in [_____] 20 ;

(viii) the Master Servicing Fee Rate will be [_____]% per annum for each Assumed Mortgage Loan; and

(ix) the initial Principal Balance of each Class of Certificates will be as set forth in the table beginning on page S-6 of this prospectus supplement.

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It is highly unlikely that the Mortgage Loans will prepay at any constant rate, that all of the Mortgage Loans will prepay at the same rate or that the Mortgage Loans will not experience any losses. In addition, there will be differences between the characteristics of the Mortgage Loans ultimately included in the Trust Estate and the characteristics which are assumed in preparing the tables, as described above. Any difference may have an effect upon the actual percentages of initial Principal Balances of the Classes of Certificates outstanding, the actual Weighted Average Lives of the Classes of Certificates and the date on which the Principal Balance of any Class of Certificates is reduced to zero.

Based upon the foregoing assumptions, the tables appearing in Appendix C indicate the Weighted Average Life of each Class of Offered Certificates, and set forth the percentages of the initial Principal Balance of each such Class of Offered Certificates that would be outstanding after each of the dates shown at constant percentages of SPA presented.

Interest accrued on the Offered Certificates will be reduced by the amount of any interest portions of Realized Losses allocated to such Certificates as described under "Description of the Certificates -- Interest" herein. The yield on the Offered Certificates (other than the Floating Rate and Inverse Floating Rate Certificates) will be less than the yield otherwise produced by their respective Pass-Through Rates, if any, and the prices at which such Certificates are purchased because the interest which accrues on the Mortgage Loans during each month will not be passed through to Certificateholders until the 25th day of the month following the end of such month (or if such 25th day is not a business day, the following business day).

Sensitivities of Certain Classes of Certificates

Certain Classes of Offered Certificates will be highly sensitive to the rate and timing of principal payments (including prepayments) on the applicable Mortgage Loans, which rate may fluctuate significantly from time to time. The Inverse Floating Rate Certificates are also highly sensitive to the rate of LIBOR. See "--General" above.

The Class A-PO Certificates will be highly sensitive to the rate and timing of principal payments (including prepayments) on the Discount Mortgage Loans.

The tables appearing in Appendix D indicate the sensitivities to various rates of prepayment on the Mortgage Loans, and changes in LIBOR in the case of the Inverse Floating Rate Certificates, of the pre-tax yields to maturity on a semi-annual corporate bond equivalent ("CBE") basis of the designated Classes.

The tables have been prepared on the basis of the Structuring Assumptions, and the additional assumptions that (1) the Class A-1, Class A-6 and Class A-PO Certificates will be purchased on the Closing Date at purchase prices equal to
[_____]%, [_____]% and [_____]%, respectively, of their initial Principal Balance plus accrued interest, where applicable, from the first day of the Interest Accrual Period to (but not including) the Closing Date and (2) in the case of the Class A-1 and Class A-6 Certificates, beginning with the Distribution Date in [_____] 20 and for each Distribution Date thereafter, LIBOR is at the level specified.

The pre-tax yields to maturity set forth in the tables appearing in Appendix D were calculated by (i) determining the monthly discount rates which, when applied to the assumed streams of cash flows to be paid on the designated Class of Certificates, would cause the discounted present value of such assumed streams of cash flows to equal the assumed purchase price for such Class set forth above and (ii) converting such monthly rates to CBE rates. Such calculations do not take into account the interest rates at which investors may be able to reinvest funds received by them as distributions on the Certificates and consequently do not purport to reflect the return on any investment in the Certificates when such reinvestment rates are considered.

Notwithstanding the assumed prepayment rates reflected in the tables appearing in Appendix D, it is highly unlikely that the applicable Mortgage Loans will prepay at a constant rate until maturity, that all of the applicable Mortgage Loans will prepay at the same rate or that the applicable Mortgage Loans will not experience any losses. It is also highly unlikely in the case of the Inverse Floating Rate Certificates that LIBOR will remain constant. In addition, there will be differences between the characteristics of the applicable Mortgage Loans ultimately included in the Trust Estate and the Assumed Mortgage Loans. As a result of these factors, the pre-tax yields to maturity on any designated Class of Certificates are likely to differ from those shown in the related table, even if all of the applicable Mortgage Loans prepay at the indicated percentages of SPA.

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The tables relating to the Inverse Floating Rate Certificates do not constitute a representation as to the correlation of any level of LIBOR with any rate of prepayments on the Mortgage Loans. Each investor must make an independent decision as to the appropriate combination of prepayment and LIBOR assumptions to be used in deciding whether or not to purchase an Inverse Floating Rate Certificate.

Yield Considerations with Respect to the Class B-2 and Class B-3 Certificates

Defaults on mortgage loans may be measured relative to a default standard or model. The model used in this prospectus supplement, the standard default assumption ("SDA"), represents an assumed rate of default each month relative to the then-outstanding performing principal balance of a pool of new mortgage loans. A default assumption of 100% SDA assumes constant default rates of 0.02% per annum of the then-outstanding principal balance of such mortgage loans in the first month of the life of the mortgage loans and an additional 0.02% per annum in each month thereafter until the 30th month. Beginning in the 30th month and in each month thereafter through the 60th month of the life of the mortgage loans, 100% SDA assumes a constant default rate of 0.60% per annum each month. Beginning in the 61st month and in each month thereafter through the 120th month of the life of the mortgage loans, 100% SDA assumes that the constant default rate declines each month by 0.0095% per annum, and that the constant default rate remains at 0.03% per annum in each month after the 120th month. As used in the tables appearing in Appendix E, "0% SDA" assumes default rates equal to 0% of SDA (no defaults). SDA does not purport to be a historical description of default experience or a prediction of the anticipated rate of default of any pool of mortgage loans, including the Mortgage Loans.

The tables appearing in Appendix E indicate the sensitivities of the pre-tax yields to maturity on a CBE basis of the Class B-2 and Class B-3 Certificates to various rates of prepayment and varying levels of aggregate Realized Losses. The tables appearing in Appendix E are based upon, among other things, the Structuring Assumptions (other than the assumption that no defaults shall have occurred with respect to the Assumed Mortgage Loans) and the additional assumptions that (i) liquidations (other than those scenarios indicated as 0% of SDA (no defaults)) occur monthly on the last day of the preceding month at the percentages of SDA set forth in the tables and (ii) all delinquency tests are met.

In addition, it was assumed that (i) Realized Losses on liquidations of
[__]% or [__]% of the outstanding principal balance of such liquidated Mortgage Loans, as indicated in the tables (referred to as a "Loss Severity Percentage") will occur at the time of liquidation, (ii) there is no delay between the default and the liquidation of the mortgage loans and (iii) the Class B-2 and Class B-3 Certificates are purchased on the Closing Date at purchase prices equal to [_____]% and [_____]%, respectively, of the initial Principal Balances thereof plus accrued interest from the first day of the initial Interest Accrual Period to (but not including) the Closing Date.

The actual Mortgage Loans ultimately included in the Trust Estate will have characteristics differing from those assumed in preparing the tables and it is unlikely that they will prepay or liquidate at any of the rates specified. In addition, it is unlikely that Realized Losses will be incurred according to any one particular pattern. The assumed percentages of SPA and SDA and the loss severities shown in the tables are for illustrative purposes only and the Depositor makes no representations with respect to the reasonableness of such assumptions or that the actual rates of prepayment and liquidation and loss severity experience of the Mortgage Loans will in any way correspond to any of the assumptions made herein. For these reasons, and because the timing of cash flows is critical to determining yield, the actual pre-tax yields to maturity of the Class B-2 and Class B-3 Certificates are likely to differ from the pre-tax yields to maturity shown in the tables.

The pre-tax yields to maturity in the tables appearing in Appendix E were calculated by (i) determining the monthly discount rates which, when applied to the assumed streams of cash flows to be paid on the Class B-2 and Class B-3 Certificates, would cause the discounted present value of such assumed streams of cash flows to equal the assumed purchase prices of the Class B-2 and Class B-3 Certificates set forth above and (ii) converting such monthly rates to CBE rates. Such calculations do not take into account the interest rates at which investors may be able to reinvest funds received by them as distributions on the Class B-2 and Class B-3 Certificates and consequently do not purport to reflect the return on any investment in the Class B-2 and Class B-3 Certificates when such reinvestment rates are considered.

Investors are urged to make their investment decisions based on their determinations as to anticipated rates of prepayment and Realized Losses under a variety of scenarios. Investors in Class B-2 and Class B-3 Certificates

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should fully consider the risk that Realized Losses on the Mortgage Loans could result in the failure of such investors to fully recover their initial investments.

POOLING AND SERVICING AGREEMENT

General

The Certificates will be issued pursuant to a Pooling and Servicing Agreement to be dated as of the Closing Date (the "Pooling and Servicing Agreement") among the Depositor, the Master Servicer and the Trustee. Reference is made to the prospectus for important additional information regarding the terms and conditions of the Pooling and Servicing Agreement and the Certificates beyond the summaries below of certain provisions specific to this transaction. See "Description of the Certificates," "Servicing of the Mortgage Loans" and "The Pooling and Servicing Agreement" in the prospectus.

The Trust Estate created pursuant to the Pooling and Servicing Agreement will consist of (i) the Mortgage Loans, (ii) such assets as from time to time are identified as deposited in any account held for the benefit of the Certificateholders, (iii) any Mortgaged Properties acquired on behalf of the Certificateholders by foreclosure or by deed in lieu of foreclosure after the Closing Date and (iv) the rights of the Trustee to receive the proceeds of all insurance policies and performance bonds, if any, required to be maintained pursuant to the Pooling and Servicing Agreement.

Compensation and Payment of Expenses of the Master Servicer, Servicer and Trustee

The primary compensation payable to the Master Servicer will be the "Master Servicing Fee" payable monthly equal to (1)/12th of the master servicing fee rate set forth in the table below (the "Master Servicing Fee Rate"). The Master Servicing Fee for each Distribution Date will accrue on the aggregate scheduled principal balance of the Mortgage Loans as of the first day of the preceding month.

The primary compensation payable to the Servicer is the aggregate of the Servicing Fees applicable to the related Mortgage Loans. The Servicer will be entitled to a "Servicing Fee" payable monthly equal to (1)/12th of the servicing fee rate set forth in the table below (the "Servicing Fee Rate"). The Servicing Fee for each Distribution Date will accrue on the scheduled principal balance of the Mortgage Loans serviced by the Servicer as of the first day of the preceding month.

The Master Servicing Fee Rate, the Servicing Fee Rate and the Trustee Fee Rate will be the per annum rate set forth in the table below:

Fees Payable From the Trust Estate(1)

       Master Servicing Fee Rate   Servicing Fee Rate   Trustee Fee Rate
       -------------------------   ------------------   ----------------
             [_____]% (2)             [____]% (2)               (3)

----------

(1) Certain expenses incurred by the Master Servicer and the Trustee are reimbursable from the Trust Estate as described under "Servicing of the Mortgage Loans--The Master Servicer--General" and "The Pooling and Servicing Agreement--The Trustee" in the prospectus.

(2) The Master Servicing Fee Rate and Servicing Fee Rate may not be changed without the consent of Certificateholders if such change adversely affects the interests of Certificateholders.

(3) The fees of the Trustee, other than the initial acceptance/legal fees of the Trustee which are paid by the Depositor, incurred in connection with its responsibilities under the Pooling and Servicing Agreement will be payable by the Master Servicer without reimbursement from the Trust Estate.

The Master Servicing Fee and Servicing Fee for the Mortgage Loans are payable out of the interest payments on the Mortgage Loans, prior to any payments to Certificateholders. The Master Servicer is also entitled to additional compensation, as described under "Servicing of the Mortgage Loans--The Master Servicer" in the prospectus. The

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Servicer is entitled to additional servicing compensation, as described under "Servicing of the Mortgage Loans--Fixed Retained Yield, Servicing Compensation and Payment of Expenses" in the prospectus.

In the event that the Trustee succeeds to the role of the Master Servicer, it will be entitled to compensation for such duties not to exceed the compensation received by the predecessor master servicer. In addition, if the Trustee appoints a successor master servicer under the Pooling and Servicing Agreement, the Trustee may make arrangements for the compensation of such successor master servicer, such compensation not to exceed the compensation received by the predecessor master servicer. All costs of a transfer of master servicing will be reimbursed to the party who incurred such costs as described under "Servicing of the Mortgage Loans--The Master Servicer" in the prospectus.

In the event that the Master Servicer or the Trustee succeeds, or another party is appointed to succeed, to the role of Servicer, such entity will be entitled to compensation for such duties, not to exceed the compensation received by the predecessor Servicer. All costs of a transfer of servicing will be reimbursed to the party who incurred such costs as described under "Servicing of the Mortgage Loans--The Servicers" in the prospectus.

The Master Servicer will pay certain administrative expenses, including fees of the Trustee incurred in connection with its responsibilities under the Pooling and Servicing Agreement. Some of these expenses of the Master Servicer are subject to rights of reimbursement as described under "Servicing of the Mortgage Loans--The Master Servicer" in the prospectus. The fees of any co-trustee whose appointment is necessary or advisable for (i) conforming to any legal requirement, restriction or condition in any state in which any Mortgaged Property or any portion of the Trust Estate is located, will be paid by the Master Servicer, without reimbursement from the Trust Estate and (ii) any reason other than contemplated by clause (i), will be paid by the Trustee, without reimbursement from the Trust Estate. Expenses incurred by a co-trustee are reimbursable from the Trust Estate to the same extent as expenses of the Trustee are reimbursable from the Trust Estate. See "The Pooling and Servicing Agreement--The Trustee" in the prospectus.

The Depositor, the Master Servicer and the Trustee are also entitled to indemnification from the Trust Estate under certain circumstances described under "The Depositor," "Servicing of the Mortgage Loans--The Master Servicer--General" and "The Pooling and Servicing Agreement--The Trustee" in the prospectus.

For so long as the Master Servicer and the Paying Agent are the same entity, the Paying Agent will not be entitled to a separate fee for its services. If the Master Servicer and the Paying Agent are no longer the same entity, the Master Servicer will pay the fees of the Paying Agent without reimbursement from the Trust.

The servicing fees and other expenses of the REMIC will be allocated to the holders of the Class A-R Certificates. See "Federal Income Tax Considerations" herein and "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates -- Limitations on Deduction of Certain Expenses" in the prospectus.

Optional Termination of the Trust

On any Distribution Date on which the aggregate Scheduled Principal Balance of the Mortgage Loans is less than 10% of the aggregate unpaid principal balance of the Mortgage Loans as of the Cut-Off Date, the Depositor may, subject to certain conditions, purchase all outstanding Mortgage Loans in the pool and thereby effect early retirement of the Certificates. See "The Pooling and Servicing Agreement--Termination; Optional Purchase of Mortgage Loans" in the prospectus. The exercise of this option will be in the Depositor's sole discretion. Without limitation, the Depositor may enter into agreements with third parties to (i) exercise such option at the direction of a third party or
(ii) forebear from the exercise of such option.

Voting

With respect to any provisions of the Pooling and Servicing Agreement providing for the action, consent or approval of the holders of all Certificates evidencing specified Voting Interests in the Trust Estate, each Class of Certificates will be entitled to a pro rata portion of the Voting Interest based on the outstanding Principal Balance of such Class. With respect to any provisions of the Pooling and Servicing Agreement providing for action, consent or approval of each Class of Certificates or specified Classes of Certificates, each Certificateholder of a Class will have

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a Voting Interest equal to the product of the Voting Interest to which such Class is collectively entitled and the Percentage Interest in such Class represented by such holder's Certificates. Unless Definitive Certificates are issued as described under "Description of the Certificates -- Book-Entry Form" in the prospectus, Beneficial Owners of Book-Entry Certificates may exercise their voting rights only through DTC Participants.

Fixed Retained Yield

A fixed percentage of the interest on each Mortgage Loan (the "Fixed Retained Yield") will be determined on a loan-by-loan basis and will not be included in the Trust Estate. The Fixed Retained Yield on each Mortgage Loan will equal the greater of (i) zero and (ii) the Mortgage Interest Rate less the sum of (a) [_____]%, (b) the applicable Servicing Fee Rate and (c) the Master Servicing Fee Rate. The amount of any Fixed Retained Yield will be retained by the Sponsor. See "Servicing of the Mortgage Loans--Fixed Retained Yield, Servicing Compensation and Payment of Expenses" in the prospectus for further information regarding Fixed Retained Yield.

FEDERAL INCOME TAX CONSIDERATIONS

General

In the opinion of Cadwalader, Wickersham & Taft LLP, the following discussion, together with the discussion under "Material Federal Income Tax Consequences" in the prospectus, summarizes the material federal income tax consequences of the purchase ownership and disposition of the Offered Certificates.

The Trust will qualify as a REMIC for federal income tax purposes. The assets of the REMIC will include the Mortgage Loans (exclusive of Fixed Retained Yield), together with the amounts held by the Master Servicer in a separate account in which collections on the Mortgage Loans will be deposited (the "Certificate Account"), the hazard insurance policies and primary mortgage insurance policies, if any, relating to the Mortgage Loans and any property that secured a Mortgage Loan that is acquired by foreclosure or deed in lieu of foreclosure.

Each Class of Offered Certificates (other than the Class A-R Certificates), together with each Class of Certificates not offered hereby (collectively, the "Regular Certificates") will be designated as regular interests in the REMIC, and the Class A-R Certificates will be designated as the residual interest in the REMIC. The Class A-R Certificates are "Residual Certificates" for purposes of the prospectus.

The Offered Certificates will be treated as "loans . . . secured by an interest in real property which is . . . residential real property" for a domestic building and loan association, "real estate assets" for a real estate investment trust and, other than the Residual Certificates, "qualified mortgages" for a REMIC to the extent described in the prospectus. See "Material Federal Income Tax Consequences - Federal Income Tax Consequences for REMIC Certificates - Status of REMIC Certificates" in the prospectus.

Regular Certificates

The Regular Certificates generally will be treated as newly originated debt instruments for federal income tax purposes. Beneficial Owners (or in the case of Definitive Certificates, holders) of the Regular Certificates will be required to report income on such Certificates in accordance with the accrual method of accounting.

It is anticipated that:

o The Class [_____] Certificates will be issued with original issue discount equal to the excess of their initial principal balance over their issue price;

o The Class [_____] Certificates will be issued with original issue discount equal to the excess of the sum of all distributions of principal and interest (whether current or accrued) expected to be received on those Certificates over their respective issue prices (including accrued interest from the first day of the initial Interest Accrual Period);

S-55

o The Class [_____] Certificates will be issued with original issue discount equal to the excess of their initial Principal Balance (plus [_____] days of accrued interest) over their issue price (including accrued interest from the first day of the initial Interest Accrual Period);

o The Class [_____] Certificates will be issued at a premium; and

o The Class [_____] Certificates will be issued with de minimis original issue discount.

It is also anticipated that the Class B-4, Class B-5 and Class B-6 Certificates, which are not offered hereby, will be issued with original issue discount.

See "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates--Taxation of Regular Certificates" in the prospectus.

The Prepayment Assumption (as defined in the prospectus) that the Master Servicer intends to use in determining the rate of accrual of original issue discount and whether the original issue discount is considered de minimis, and that may be used by Beneficial Owners (or holders) to amortize premium, will be calculated using [____]% SPA for the Mortgage Loans. No representation is made as to the actual rate at which the Mortgage Loans will prepay.

If the method for computing original issue discount results in a negative amount for any period with respect to any holder of Offered Certificates, the amount of original issue discount allocable to that period would be zero. The holder would be permitted to offset the negative amount only against future original issue discount, if any, attributable to his or her Certificates. Any loss might be treated as a capital loss.

Residual Certificates

The holders of the Class A-R Certificates must include the taxable income or loss of the REMIC in determining their federal taxable income. The Residual Certificates will remain outstanding for federal income tax purposes until there are no Certificates of any other Class outstanding. Prospective investors are cautioned that the Residual Certificateholders' REMIC taxable income and the tax liability thereon may exceed, and may substantially exceed, cash distributions to such holders during certain periods, in which event, the holders thereof must have sufficient alternative sources of funds to pay such tax liability. Furthermore, it is anticipated that all or a substantial portion of the taxable income of the REMIC includible by the holders of the Class A-R Certificates will be treated as "excess inclusion" income, resulting in (i) the inability of such holders to use net operating losses to offset such income from the REMIC, (ii) the treatment of such income as "unrelated business taxable income" to certain holders who are otherwise tax-exempt and (iii) the treatment of such income as subject to 30% withholding tax to certain non-U.S. investors, with no exemption or treaty reduction.

The Residual Certificates will be considered "noneconomic residual interests," with the result that transfers thereof would be disregarded for federal income tax purposes if any significant purpose of the transferor was to impede the assessment or collection of tax. Accordingly, the Residual Certificates are subject to certain restrictions on transfer and any prospective transferee thereof will be required to furnish to the Master Servicer an affidavit as described under "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates--Taxation of Residual Certificates--Tax-Related Restrictions on Transfer of Residual Certificates--Noneconomic Residual Interests" in the prospectus. See also "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates--Taxation of Residual Certificates--Limitations on Offset or Exemption of REMIC Income" in the prospectus.

An individual, trust or estate that holds a Residual Certificate (whether such Certificate is held directly or indirectly through certain pass-through entities) also may have additional gross income with respect to, but may be subject to limitations on the deductibility of, Servicing Fees on the Mortgage Loans and other administrative expenses of the REMIC in computing such holder's regular tax liability, and may not be able to deduct such fees or expenses to any extent in computing such holder's alternative minimum tax liability. In addition, some portion of a purchaser's basis, if any, in a Residual Certificate may not be recovered until termination of the Trust Estate.

S-56

Due to the special tax treatment of residual interests, the effective after-tax return of the Residual Certificates may be significantly lower than would be the case if the Residual Certificates were taxed as debt instruments, or may be negative.

See "Material Federal Income Tax Consequences" in the prospectus.

ERISA CONSIDERATIONS

The Residual Certificates may not be purchased by or transferred to a Plan or a person acting on behalf of or investing the assets of a Plan. See "Description of the Certificates--Restrictions on Transfer of the Residual Certificates" herein.

Accordingly, the following discussion applies to the Offered Certificates (other than the Residual Certificates) and does not purport to discuss the considerations under ERISA, Code Section 4975 or Similar Law with respect to the purchase, acquisition or resale of a Residual Certificate.

As described in the prospectus under "ERISA Considerations," ERISA and the Code impose certain duties and restrictions on ERISA Plans and certain persons who perform services for ERISA Plans. Comparable duties and restrictions may exist under Similar Law on governmental plans and certain persons who perform services for governmental plans. For example, unless exempted, investment by a Plan in the Offered Certificates may constitute a prohibited transaction under ERISA, the Code or Similar Law. There are certain exemptions issued by the United States Department of Labor (the "DOL") that may be applicable to an investment by an ERISA Plan in the Offered Certificates, including the individual administrative exemptions described below. For a further discussion of the individual administrative exemption, including the necessary conditions to its applicability, and other important factors to be considered by an ERISA Plan contemplating investing in the Offered Certificates, see "ERISA Considerations" in the prospectus.

The DOL issued an Underwriter Exemption to [_____]. This Underwriter Exemption might apply to the acquisition, holding and resale of the Offered Certificates by an ERISA Plan, provided that specified conditions are met.

Among the conditions which would have to be satisfied for the Underwriter Exemption to apply to the acquisition by an ERISA Plan of the Offered Certificates is the condition that the ERISA Plan investing in the Offered Certificates be an "accredited investor" as defined in Rule 501(a)(1) of Regulation D of the Securities and Exchange Commission under the Securities Act of 1933, as amended (the "Securities Act").

Before purchasing an Offered Certificate, a fiduciary of an ERISA Plan should make its own determination as to the availability of the exemptive relief provided in the Underwriter Exemption or the availability of any other prohibited transaction exemptions, and whether the conditions of any such exemption will be applicable to the Offered Certificates, and a fiduciary of a governmental plan should make its own determination as to the need for and availability of any exemptive relief under Similar Law. Any fiduciary of an ERISA Plan considering whether to purchase an Offered Certificate should also carefully review with its own legal advisors the applicability of the fiduciary duty and prohibited transaction provisions of ERISA and the Code to such investment. See "ERISA Considerations" in the prospectus.

LEGAL INVESTMENT

The Class A and Class B-1 Certificates will constitute "mortgage related securities" for purposes of the Secondary Mortgage Market Enhancement Act of 1984, as amended ("SMMEA") so long as they are rated in one of the two highest rating categories by at least one nationally recognized statistical rating organization. The Class B-2 and Class B-3 Certificates will not constitute "mortgage related securities" under SMMEA.

Prospective purchasers, particularly those whose investment activities are subject to legal investment laws and regulations, regulatory capital requirements or review by regulatory authorities, may be subject to restrictions on investment in the Offered Certificates and should consult their own legal, tax, financial and accounting advisors in

S-57

determining the suitability of and consequences to them of the purchase, ownership and disposition of the Offered Certificates. See "Legal Investment" in the prospectus.

SECONDARY MARKET

There will not be any market for the Offered Certificates prior to the issuance thereof. The Underwriter intends to act as a market maker in the Offered Certificates, subject to applicable provisions of federal and state securities laws and other regulatory requirements, but is under no obligation to do so. There can be no assurance that a secondary market in the Offered Certificates will develop or, if such a market does develop, that it will provide holders of Offered Certificates with liquidity of investment at any particular time or for the life of the Offered Certificates.

PLAN OF DISTRIBUTION

Subject to the terms and conditions of the underwriting agreement dated
[_____] and the terms agreement dated [_____] (together, the "Underwriting Agreement") among Wells Fargo Bank, the Depositor and [_____], as underwriter, (the "Underwriter"), the Offered Certificates are being purchased from the Depositor by the Underwriter upon issuance thereof. The Underwriter, which is not an affiliate of the Depositor, is committed to purchase all of the Offered Certificates if any such Certificates are purchased. The Underwriter has advised the Depositor that it proposes to offer the Offered Certificates, from time to time, for sale in negotiated transactions or otherwise at prices determined at the time of sale. Proceeds to the Depositor from the sale of the Offered Certificates are expected to be approximately $[_____], plus accrued interest thereon from the Cut-Off Date to (but not including) the Closing Date before deducting expenses payable by the Depositor estimated to be $[_____]. The underwriting compensation of the Underwriter will consist of the difference between the amount paid by the Underwriter to the Depositor for the Offered Certificates and the aggregate amount received by the Underwriter upon sale by it of the Offered Certificates to investors. The Underwriter has advised the Depositor that it has not allocated the purchase price paid to the Depositor for the Class A Non-PO Certificates among such Classes and has allocated the purchase price paid to the Depositor for the Class A-PO Certificates. Any dealers that participate with the Underwriter in the distribution of the Offered Certificates will be underwriters, and any discounts or commissions received by them and any profit on the resale of Offered Certificates by them will be underwriting discounts or commissions under the Securities Act.

[The following disclosure will be included in any prospectus supplement relating to a Trust Fund containing Mortgage Certificates: The distribution of the Offered Certificates also constitutes a distribution of the Mortgage Certificates. This description of the distribution of the Offered Certificates also constitutes a current description of the distribution of the Mortgage Certificates. Each of the Issuing Entity, Depositor, Sponsor and Underwriter is also an underwriter for the offering of the Mortgage Certificates.]

The Underwriting Agreement provides that the Depositor or the Sponsor will indemnify the Underwriter against certain civil liabilities under the Securities Act or contribute to payments which the Underwriter may be required to make in respect thereof.

LEGAL MATTERS

The legality of the Offered Certificates and certain tax matters with respect thereto will be passed upon for the Depositor by Cadwalader, Wickersham & Taft LLP, New York, New York. Certain legal matters will be passed upon for the Underwriter by Stroock & Stroock & Lavan LLP, New York, New York.

USE OF PROCEEDS

The net proceeds to be received from the sale of the Offered Certificates will be applied by the Depositor to the purchase from the Sponsor of the Mortgage Loans underlying the Certificates.

S-58

RATINGS

It is a condition to the issuance of the Offered Certificates that each such class will have received at least the rating set forth in the table beginning on page S-6 from [_____] ("[_____]") and [_____] ("[_____]," and together with [_____], the "Rating Agencies"). A security rating is not a recommendation to buy, sell or hold securities or to undertake any investment strategy with respect to any security and may be subject to revision or withdrawal at any time by the assigning rating agency. Each security rating should be evaluated independently of any other security rating. The ratings do not comment on the adequacy of market price, the suitability of any security for a particular investor (including without limitation, any accounting, tax and/or regulatory treatment).

The ratings of [_____] on mortgage pass-through certificates address the likelihood of the receipt by certificateholders of all distributions to which such certificateholders are entitled. [_____]'s rating opinions address the structural and legal aspects associated with the certificates, including the nature of the underlying mortgage loans. [_____]'s ratings on mortgage pass-through certificates do not represent any assessment of the likelihood or rate of principal prepayments and consequently any adverse effect the timing of such prepayments could have on an investor's anticipated yield.

The ratings of [_____] on mortgage pass-through certificates address the likelihood of the receipt by certificateholders of all distributions of principal and interest to which such certificateholders are entitled. [_____]'s rating opinions address the structural, legal and issuer aspects associated with the certificates, including the nature of the underlying mortgage loans and the credit quality of the credit support provider, if any. [_____]'s ratings on mortgage pass-through certificates do not represent any assessment of the likelihood that principal prepayments may differ from those originally anticipated and consequently any adverse effect the timing of such prepayments could have on an investor's anticipated yield.

The ratings of [_____] and [_____] on a Class of Principal Only Certificates only address the return of the Principal Balance of such Class.

The Depositor has not requested a rating on the Offered Certificates of any Class by any rating agency other than [_____] and [_____], although data with respect to the Mortgage Loans may have been provided to other rating agencies solely for their informational purposes. There can be no assurance that any rating assigned by any other rating agency to the Offered Certificates will be as high as those assigned by [_____] and [_____]. In addition, the Rating Agencies will monitor the initial ratings of the Offered Certificates for so long as they remain outstanding.

S-59

INDEX OF PROSPECTUS SUPPLEMENT DEFINITIONS

Accretion Termination Date..................................................S-32
Accrual Distribution Amount.................................................S-32
Adjusted Pool Amount........................................................S-31
Adjusted Pool Amount (Non-PO Portion).......................................S-31
Adjusted Pool Amount (PO Portion)...........................................S-31
Aggregate Non-PO Principal Balance..........................................S-31
Aggregate Principal Balance.................................................S-30
Assumed Discount Mortgage Loans.............................................S-50
Assumed Mortgage Loans......................................................S-50
Assumed Premium Mortgage Loans..............................................S-50
BPMI Policy.................................................................S-44
CBE.........................................................................S-51
Certificate Account.........................................................S-55
Certificates................................................................S-27
Class A Certificates........................................................S-27
Class A Non-PO Optimal Principal Amount.....................................S-33
Class A Non-PO Principal Balance............................................S-30
Class A Non-PO Principal Distribution Amount................................S-33
Class A Percentage..........................................................S-35
Class A Prepayment Percentage...............................................S-35
Class A Principal Balance...................................................S-30
Class A-PO Deferred Amount..................................................S-34
Class A-PO Distribution Amount..............................................S-33
Class A-PO Optimal Principal Amount.........................................S-33
Class B Certificates........................................................S-27
Class B Optimal Principal Amount............................................S-33
Class B Percentage..........................................................S-36
Class B Prepayment Percentage...............................................S-36
Class B Principal Balance...................................................S-30
Class B Principal Distribution Amount.......................................S-33
Class Percentage............................................................S-34
Class Prepayment Percentage.................................................S-34
CLTV........................................................................S-44
Code........................................................................S-40
Combined Loan-to-Value Ratio................................................S-44
Current Fractional Interest.................................................S-36
Custodial Agreement.........................................................S-26
Custodian...................................................................S-26
Delinquency and Loss Tests..................................................S-35
Depositor...................................................................S-24
Discount Mortgage Loan......................................................S-35
DOL.........................................................................S-57
ERISA.......................................................................S-40
ERISA Plan..................................................................S-40
FICO Scores.................................................................S-45
Fixed Retained Yield........................................................S-55
FSMA.........................................................................S-5
HSBC Bank...................................................................S-25
Interest Accrual Period.....................................................S-29
Interest Shortfall Amount...................................................S-32
LIBOR Based Interest Accrual Period.........................................S-29
Loss Severity Percentage....................................................S-52
LPMI Policy.................................................................S-44
Master Servicer.............................................................S-25
Master Servicing Fee........................................................S-53
Master Servicing Fee Rate...................................................S-53
Mortgage Loans..............................................................S-43
Mortgaged Properties........................................................S-43
Mortgages...................................................................S-43
Net Mortgage Interest Rate..................................................S-31
Non-PO Fraction.............................................................S-34
Non-Supported Interest Shortfalls...........................................S-31
Offered Certificates........................................................S-27
Original Class B Principal Balance..........................................S-35
Original FICO Scores........................................................S-45
Original Fractional Interest................................................S-36
Original Total Debt-to-Income Ratio.........................................S-45
PAC Certificates............................................................S-37
PAC Groups..................................................................S-37
PAC I Certificates..........................................................S-37
PAC I Group.................................................................S-37
PAC I Group Principal Amount................................................S-37
PAC II Certificates.........................................................S-37
PAC II Group................................................................S-37
PAC II Group Principal Amount...............................................S-37
PAC Principal Amount........................................................S-37
Pass-Through Rate...........................................................S-30
Paying Agent................................................................S-26
Payment Account.............................................................S-26
Percentage Interest.........................................................S-29
Periodic Advance............................................................S-40
Plan........................................................................S-40
PO Fraction.................................................................S-35
Pool Balance (Non-PO Portion)...............................................S-35
Pool Balance (PO Portion)...................................................S-35
Pool Distribution Amount....................................................S-27
Pool Distribution Amount Allocation.........................................S-28
Pooling and Servicing Agreement.............................................S-53
Premium Mortgage Loan.......................................................S-35
Prepayment Shift Percentage.................................................S-38
Principal Payments..........................................................S-39
Priority Amount.............................................................S-37
Priority Percentage.........................................................S-38
PUDs........................................................................S-44
Rating Agencies.............................................................S-59
Record Date.................................................................S-27
Regular Certificates........................................................S-55
Regular Interest Accrual Period.............................................S-29
Relevant Implementation Date.................................................S-4
Relevant Member State........................................................S-4
Relevant Persons.............................................................S-5
Relief Act Shortfalls.......................................................S-32
Scheduled Principal Amount..................................................S-38
SDA.........................................................................S-52
Securities Act..............................................................S-57

                                      S-60

Servicer....................................................................S-26
Servicer Modification.......................................................S-36
Servicing Fee...............................................................S-53
Servicing Fee Rate..........................................................S-53
Shift Percentage............................................................S-38
Similar Law.................................................................S-40
SMMEA.......................................................................S-57
SPA.........................................................................S-50
Structuring Assumptions.....................................................S-50
Subordinated Certificates...................................................S-27
Subordinated Percentage.....................................................S-36
Subordinated Prepayment Percentage..........................................S-36
Subordination Depletion Date................................................S-41
Trust.......................................................................S-24
Trustee.....................................................................S-25
Underlying Servicing Agreement..............................................S-26
Underwriter.................................................................S-58
Underwriting Agreement......................................................S-58
Underwriting Standards......................................................S-45
Unscheduled Principal Amount................................................S-38
Weighted Average Life.......................................................S-50
Wells Fargo Bank............................................................S-23
Wells Fargo Underlying Servicing Agreement..................................S-26

S-61

APPENDIX A

SELECTED MORTGAGE LOAN DATA
(as of the Cut-Off Date)

                                                                                             All      Premium    Discount
                                                                                           Mortgage   Mortgage   Mortgage
                                                                                            Loans      Loans      Loans
                                                                                           --------   --------   --------
Number of Mortgage Loans.................................................................
Aggregate Unpaid Principal Balance.......................................................
Range of Unpaid Principal Balances.......................................................
Average Unpaid Principal Balance.........................................................
Range of Current Mortgage Interest Rates.................................................
Weighted Average Current Mortgage Interest Rate..........................................
Weighted Average Current Net Mortgage Interest Rate......................................
Range of Remaining Terms to Stated Maturity..............................................
Weighted Average Remaining Term to Stated Maturity.......................................
Range of Original Loan-to-Value Ratios...................................................
Weighted Average Original Loan-to-Value Ratio............................................
Number of Mortgage Loans with Original Loan-to-Value Ratios greater
   than 80% not covered by Primary Mortgage Insurance....................................
Mortgage Loans with Original Loan-to-Value Ratios greater than 80% not
   covered by Primary Mortgage Insurance as a Percentage of Aggregate
   Unpaid Principal Balance..............................................................
Number of Mortgage Loans covered by an LPMI Policy.......................................
Mortgage Loans covered by an LPMI Policy as a Percentage of Aggregate
   Unpaid Principal Balance..............................................................
Number of Interest Only Loans (1)........................................................
Interest Only Loans (1) as a Percentage of Aggregate Unpaid Principal
   Balance...............................................................................
Range of Interest Only Term for Interest Only Mortgage Loans (1).........................
Weighted Average Remaining Interest Only Term for Interest Only
   Mortgage Loans (1)....................................................................
Range of Original Debt to Income Ratios..................................................
Weighted Average Original Total Debt to Income Ratio.....................................
Range of Loan Age........................................................................
Weighted Average Loan Age................................................................
Aggregate Original Unpaid Principal Balance..............................................
Weighted Average Original Loan-to-Value Ratio of Mortgage Loans with
   Original Principal Balances greater than $600,000.....................................
Maximum Original Loan-to-Value Ratio of Mortgage Loans with Original
   Principal Balances
   greater than $600,000.................................................................
Geographic Concentration of Mortgaged Properties Securing Mortgage
   Loans in Excess of 5% of the Aggregate Unpaid Principal Balance
     [State].............................................................................
     [State].............................................................................
Maximum Five-Digit Zip Code Concentration................................................
Earliest Origination Month...............................................................
Latest Origination Month.................................................................
Latest Stated Maturity Date..............................................................
Number of Buy-Down Loans (2).............................................................
Buy-Down Loans (2) as a Percentage of Aggregate Unpaid Principal
   Balance...............................................................................
Number of Relocation Mortgage Loans (3)..................................................
Relocation Mortgage Loans (3) as a Percentage of Aggregate Unpaid
   Principal Balance.....................................................................
Number of Subsidy Loans (4)..............................................................
Subsidy Loans (4) as a Percentage of Aggregate Unpaid Principal Balance..................
Number of Home Asset ManagementSM Account Loans (5)......................................
Home Asset ManagementSM Account Loans (5) as a Percentage of Aggregate
   Unpaid Principal Balance..............................................................
Number of LOC Pledged Asset Mortgage Loans (6)...........................................
LOC Pledged Asset Mortgage Loans (6) as a Percentage of Aggregate
   Unpaid Principal Balance..............................................................
Weighted Average Original FICO Score(7)..................................................


(1) For a description of Interest Only Loans, see "The Trust Estates-Mortgage Loans" in the prospectus.

A-1

(2) For a description of Buydown Loans, see "The Trust Estates-Mortgage Loans" in the prospectus.

(3) A Relocation Mortgage Loan is a mortgage loan originated in connection with the purchase of a residence of a relocated employee of various corporate employers that participated in the relocation program of Wells Fargo Bank and of various non-participant employers.

(4) For a description of Subsidy Loans, see "The Trust Estates-Mortgage Loans" in the prospectus.

(5) For a description of Home Asset ManagementSM Account Loans, see "The Sponsor's Mortgage Loan Programs-Mortgage Loan Underwriting" in the prospectus.

(6) For a description of LOC Pledged Asset Mortgage Loans, see "The Trust Estates-Mortgage Loans" in the prospectus.

(7) Does not include the Mortgage Loans for which FICO Scores are not available.

A-2

APPENDIX A (Continued)

MORTGAGE LOAN DATA

CURRENT MORTGAGE INTEREST RATES

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
    Range of Current                Principal   Unpaid Principal
Mortgage Interest Rates    Number    Balance        Balance
------------------------   ------   ---------   ----------------

                        ------   ---------   ----------------
Total.............
                        ======   =========   ================

DOCUMENTATION LEVELS

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
                                    Principal   Unpaid Principal
  Documentation Level      Number    Balance        Balance
------------------------   ------   ---------   ----------------
Full Documentation...
Income Verification..
Asset Verification...
No Documentation.....
                           ------   ---------   ----------------
   Total.............
                           ======   =========   ================

                       REMAINING TERMS TO STATED MATURITY

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
Remaining Stated                    Principal   Unpaid Principal
 Term (Months)             Number    Balance        Balance
------------------------   ------   ---------   ----------------

                        ------   ---------   ----------------
Total.............
                        ======   =========   ================

YEARS OF ORIGINATION

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
                                    Principal   Unpaid Principal
Year of Origination        Number    Balance        Balance
------------------------   ------   ---------   ----------------

                           ------   ---------   ----------------
   Total.............
                           ======   =========   ================

                                 PROPERTY TYPES

                                                         Percentage of
                                                        Total Aggregate
                                    Aggregate Unpaid    Unpaid Principal
Property Type              Number   Principal Balance       Balance
------------------------   ------   -----------------   ----------------
Single-family
   dwellings............
Two-to four-family units
Condominiums
   High-rise (greater
   than four  stories)..
   Low-rise (four
   stories or less).....
Cooperative Units.......
Manufactured Homes......
                           ------   -----------------   ----------------
   Total................
                           ======   =================   ================

                                GEOGRAPHIC AREAS

                                                         Percentage of
                                                        Total Aggregate
                                    Aggregate Unpaid    Unpaid Principal
    Geographic Area        Number   Principal Balance       Balance
------------------------   ------   -----------------   ----------------
Arizona.................
California..............
Colorado................
District of Columbia....
Florida.................
Georgia.................
Hawaii..................
Illinois................
Iowa....................
Maryland................
Massachusetts...........
Michigan................
Minnesota...............
Missouri................
Montana.................
Nevada..................
New Jersey..............
New York................
North Dakota............
Ohio....................
Oregon..................
Pennsylvania............
Texas...................
Virginia................
Washington..............
Wisconsin...............
                           ------   -----------------   ----------------
   Total................
                           ======   =================   ================

A-3

APPENDIX A (Continued)

MORTGAGE LOAN DATA

ORIGINAL LOAN-TO-VALUE RATIOS

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
 Range of Original                  Principal   Unpaid Principal
Loan-to-Value Ratios       Number    Balance        Balance
------------------------   ------   ---------   ----------------

                        ------   ---------   ----------------
Total.............
                        ======   =========   ================

ORIGINAL FICO SCORES

                                             Percentage
                                              of Total      Weighted
                                             Aggregate       Average
  Range of                                     Unpaid       Original
Original FICO            Aggregate Unpaid    Principal    Loan-to-Value
   Scores       Number   Principal Balance    Balance         Ratio
-------------   ------   -----------------   ----------   -------------

                ------   -----------------   ----------   -------------
Total/
 Weighted....
                ======   =================   ==========   =============

ORIGINAL PRINCIPAL BALANCES

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
     Range of                       Principal   Unpaid Principal
Principal Balance          Number    Balance        Balance
------------------------   ------   ---------   ----------------

                           ------   ---------   ----------------
   Total.............
                           ======   =========   ================

                                  ORIGINATORS

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
                                    Principal   Unpaid Principal
       Originator          Number    Balance        Balance
------------------------   ------   ---------   ----------------
Wells Fargo Bank or
   Affiliate.........
[10% Originator].....
[10% Originator].....
Other Originators....
                           ------   ---------   ----------------
   Total.............
                           ======   =========   ================

                                    PURPOSES

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
                                    Principal   Unpaid Principal
        Purpose            Number    Balance        Balance
------------------------   ------   ---------   ----------------
Purchase.............
Equity Take Out
   Refinance.........
Rate/Term Refinance..
                           ------   ---------   ----------------
   Total.............
                           ======   =========   ================

A-4

APPENDIX A (Continued)

MORTGAGE LOAN DATA

OCCUPANCY TYPES

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
                                    Principal   Unpaid Principal
     Occupancy Type        Number    Balance        Balance
------------------------   ------   ---------   ----------------
Investment Property..
Primary Residence....
Second Home..........
                           ------   ---------   ----------------
   Total.............
                           ======   =========   ================

REMAINING INTEREST ONLY TERMS

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
Remaining Interest                  Principal   Unpaid Principal
Only Term (Months)         Number    Balance        Balance
------------------------   ------   ---------   ----------------

                        ------   ---------   ----------------
Total.............
                        ======   =========   ================

ORIGINAL DEBT TO INCOME RATIOS

                                    Aggregate    Percentage of
                                     Unpaid     Total Aggregate
 Range of Debt to                   Principal   Unpaid Principal
  Income Ratios            Number    Balance        Balance
------------------------   ------   ---------   ----------------

                        ------   ---------   ----------------
Total.............
                        ======   =========   ================

ORIGINAL COMBINED LOAN-TO-VALUE RATIOS

                                    Aggregate    Percentage of
Range of Original                    Unpaid     Total Aggregate
  Combined Loan                     Principal   Unpaid Principal
 to-Value Ratios           Number    Balance        Balance
------------------------   ------   ---------   ----------------

                        ------   ---------   ----------------
Total.............
                        ======   =========   ================

A-5

APPENDIX A (Continued)

MORTGAGE LOAN DATA

ORIGINAL LOAN-TO-VALUE RATIOS

                                             Percentage
                                              of Total      Weighted
                                             Aggregate       Average
Range of                                       Unpaid       Original
Original FICO            Aggregate Unpaid    Principal    Loan-to-Value
Scores          Number   Principal Balance    Balance         Ratio
-------------   ------   -----------------   ----------   -------------

                ------   -----------------   ----------   -------------
Total/
 Weighted....
                ======   =================   ==========   =============

HISTORICAL LOAN DELINQUENCY DATA

                     Past     Past     Past
                     0-12    13-24    25-36
Delinquency         Months   Months   Months
-----------------   ------   ------   ------
Ever 30-59 Days
Ever 60-89 Days
Ever 90-119 Days
Ever 120-149 Days
Ever 150-179 Days
Ever 180-359 Days
Ever 2 Years
Ever 3 Years
Ever 3+ Years
Ever Foreclosure
Ever Bankruptcy
                    ------   ------   ------
   Total.........
                    ======   ======   ======

A-6

APPENDIX B

ASSUMED MORTGAGE LOAN CHARACTERISTICS

                                     Principal         Current                Remaining Term  Original Term to  Original Balloon
                                 Balance as of the    Mortgage     Servicing   to Maturity        Maturity            Term
                                   Cut-Off Date     Interest Rate  Fee Rate    (in Months)      (in Months)       (in Months)
                                 -----------------  -------------  ---------  --------------  ----------------  ----------------

Assumed Discount Mortgage Loans

1.
2.

Assumed Premium Mortgage Loans

1.
2.

B-1

APPENDIX C - Decrement Tables

The following tables have been prepared based on the assumptions described in this prospectus supplement under "Prepayment and Yield Considerations" and should be read in conjunction with that section.

Percentage of Initial Principal Balance Outstanding For:

                                     Class A-PO                                  Class A-1 and Class A-2
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                                SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----








































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-1

APPENDIX C (Continued)

Percentage of Initial Principal Balance Outstanding For:

                              Class A-3 and Class A-15                                  Class A-4
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                               SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----








































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-2

APPENDIX C (Continued)

Percentage of Initial Principal Balance Outstanding For:

                               Class A-5 and Class A-6                                  Class A-7
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                               SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----











































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-3

APPENDIX C (Continued)

Percentage of Initial Principal Balance Outstanding For:

                                      Class A-8                                         Class A-9
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                               SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----








































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-4

APPENDIX C (Continued)

Percentage of Initial Principal Balance Outstanding For:

                                     Class A-10                                         Class A-11
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                               SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----








































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-5

APPENDIX C (Continued)

Percentage of Initial Principal Balance Outstanding For:

                              Class A-12 and Class A-14                                 Class A-13
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                               SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----








































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-6

APPENDIX C (Continued)

Percentage of Initial Principal Balance Outstanding For:

                                     Class A-R                              Class B-1, Class B-2 and Class B-3
                                 Certificates at the                               Certificates at the
                               Following Percentages of                          Following Percentages of
                                         SPA                                               SPA
                   -----------------------------------------------   -----------------------------------------------
Distribution Date    0%  100%  250%  300%  400%  500%  750%   1000%    0%  100%  250%  300%  400%  500%  750%   1000%
-----------------  ---   ---   ---   ---   ---   ---   ---   -----   ---   ---   ---   ---   ---   ---   ---   -----








































Weighted
  Average Life
  (years)(1)


(1) The weighted average life of an Offered Certificate is determined by (i) multiplying the amount of net reduction of Principal Balance by the number of years from the date of the issuance of such Certificate to the related Distribution Date, (ii) adding the results and (iii) dividing the sum by the aggregate net reduction of Principal Balance referred to in clause (i).

* Indicates a percentage greater than zero but less than 0.5% of the initial Principal Balance of such Class.

C-7

APPENDIX D -Senior Sensitivity Tables

Sensitivity of the Pre-Tax Yield to Maturity of the Class A-PO Certificates to Prepayments at an Assumed Purchase Price of [_____]% of the Initial Principal Balance (plus Accrued Interest)

                                                  Percentages of SPA
                                 -----------------------------------------------
                                   0%  100%  250%  300%  400%  500%  750%  1000%
                                 ---   ---   ---   ---   ---   ---   ---  -----
Pre-Tax Yield To Maturity (CBE)

Sensitivity of the Pre-Tax Yield to Maturity of the Class A-1 Certificates to Prepayments at an Assumed Purchase Price of [_____]% of the Initial Principal Balance (plus Accrued Interest)

Percentages of SPA

Level of LIBOR 0% 100% 250% 300% 400% 500% 750% 1000%

Sensitivity of the Pre-Tax Yield to Maturity of the Class A-6 Certificates to Prepayments at an Assumed Purchase Price of [_____]% of the Initial Principal Balance (plus Accrued Interest)

Percentages of SPA

Level of LIBOR 0% 100% 125% 250% 300% 400% 500% 750% 1000%

Sensitivity of the Pre-Tax Yield to Maturity of the Class A-7 Certificates to Prepayments at an Assumed Purchase Price of [_____]% of the Initial Principal Balance (plus Accrued Interest)

Percentages of SPA

Level of LIBOR 7% 9% 10% 11% 20% 50% 75% 1000%

D-1

APPENDIX E - Subordinate Sensitivity Tables

Sensitivity of Pre-Tax Yields to Maturity of the Class B-2 Certificates to Prepayments and Realized Losses at an Assumed Purchase Price of [_____]% of the Initial Principal Balance (plus Accrued Interest)

                                  Loss
                                Severity
Percentage of SDA              Percentage              Percentages of SPA
-----------------------------  ----------  --------------------------------------------
                                           0%  100%  250%  300%  400%  500%  750%  1000%
                                           --  ----  ----  ----  ----  ----  ----  -----

** The pre-tax yield to maturity will be less than (99.99)%

Sensitivity of Pre-Tax Yields to Maturity of the Class B-3 Certificates to Prepayments and Realized Losses at an Assumed Purchase Price of [_____]% of the Initial Principal Balance ( plus Accrued Interest)

                                  Loss
                                Severity
Percentage of SDA              Percentage              Percentages of SPA
-----------------------------  ----------  --------------------------------------------
                                           0%  100%  250%  300%  400%  500%  750%  1000%
                                           --  ----  ----  ----  ----  ----  ----  -----

** The pre-tax yield to maturity will be less than (99.99)%

The following table sets forth the amount of Realized Losses that would be incurred with respect to the Mortgage Loans under the assumptions used to generate the pre-tax yields to maturity in the preceding tables, expressed as a percentage of the aggregate outstanding principal balance of the Mortgage Loans as of the Cut-Off Date.

                                  Loss
                                Severity
Percentage of SDA              Percentage              Percentages of SPA
-----------------------------  ----------  --------------------------------------------
                                           0%  100%  250%  300%  400%  500%  750%  1000%
                                           --  ----  ----  ----  ----  ----  ----  -----

E-1

APPENDIX F - Planned Principal Balances

The following table sets forth for each Distribution Date the planned Principal Balances for the PAC I Group, expressed as a percentage of the initial aggregate Principal Balance of the PAC I Group.

Planned Principal Balances as Percentages of Initial Aggregate Principal Balance

PAC I Group

Percentages of Initial
Aggregate Principal
Distribution Date Balance

F-1

APPENDIX F (Continued)

The following table sets forth for each Distribution Date the planned Principal Balances for the PAC II Group, expressed as a percentage of the initial aggregate Principal Balance of the PAC II Group.

Planned Principal Balances as Percentages of Initial Aggregate Principal Balance

PAC II Group

Percentages of Initial
Aggregate Principal
Distribution Date Balance

F-2

                                          [WELLS FARGO LOGO]

Wells Fargo Asset Securities Corporation
                Depositor

         Wells Fargo Bank, N.A.
       Sponsor and Master Servicer

 Wells Fargo Alternative Loan 20 - Trust
             Issuing Entity

$[________________________]


(Approximate)

Mortgage Asset-Backed Pass-Through Certificates, Series 20 -


PROSPECTUS SUPPLEMENT


[Underwriter]

You should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus. No one has been authorized to provide you with different information.

The Offered Certificates are not being offered in any state where the offer is not permitted.

The Depositor does not claim the accuracy of the information in this prospectus supplement and the accompanying prospectus as of any date other than the dates stated on their respective covers.

Upon request, dealers will deliver a prospectus supplement and prospectus when acting as underwriters of the Offered Certificates and with respect to their unsold allotments or subscriptions. In addition, upon request all dealers selling the Offered Certificates will deliver a prospectus supplement and prospectus until ninety days following the date of this prospectus supplement.

[_____], 20


SUBJECT TO COMPLETION DATED MAY 20, 2008

PROSPECTUS

Wells Fargo Asset Securities Corporation
Depositor

Mortgage Asset-Backed Pass-Through Certificates
(Issuable in Series)


The information in this prospectus is not complete and may be changed. We may not sell these certificates until we deliver a final prospectus supplement and prospectus. This prospectus and the accompanying prospectus supplement are not an offer to sell these certificates and are not soliciting an offer to buy these certificates in any state where the offer or sale is not permitted.


You should carefully consider the risk factors beginning on page 12 of this prospectus.

Except as otherwise described in the applicable prospectus supplement, neither the certificates of any series nor the related underlying mortgage assets will be insured or guaranteed by any governmental agency or instrumentality or any other entity.

The certificates of each series will represent interests in the related issuing entity only and will not represent interests in or obligations of the depositor, the sponsor or any other entity.

This prospectus may be used to offer and sell any series of certificates only if accompanied by the prospectus supplement for that series.


Each Issuing Entity--

o will issue a series of mortgage asset-backed pass-through certificates, which will consist of one or more classes of certificates; and

o will own:

o a pool or pools of fixed or adjustable interest rate, mortgage loans which are secured by a first lien on a one- to four-family residential property; and/or

o mortgage-backed certificates that represent an interest in a pool or pools of mortgage loans.

Each Pool of Mortgage Assets--

o will be sold to the related issuing entity by the depositor, who will have in turn purchased the mortgage assets from Wells Fargo Bank, N.A.;

o will, in the case of mortgage loans, be underwritten to Wells Fargo Bank, N.A.'s standards or such other standards as described in this prospectus and the applicable prospectus supplement; and

o will, in the case of mortgage loans, be serviced by Wells Fargo Bank, N.A. individually or together with other servicers.

Each Series of Certificates--

o will represent interests in the related issuing entity;

o may provide credit support for certain classes by "subordinating" certain classes to other classes of certificates; any subordinate classes will be entitled to payment subject to the payment of more senior classes and may bear losses before more senior classes;

o may be entitled to the benefit of one or more of the other types of credit support or derivative instruments described in this prospectus and in more detail in the applicable prospectus supplement; and

o will be paid only from the assets of the related issuing entity.

Neither the SEC nor any state securities commission has approved the certificates or determined that this prospectus is accurate or complete. Any representation to the contrary is a criminal offense.


The date of this prospectus is [ ], 20


TABLE OF CONTENTS
PROSPECTUS

                                                                            Page

Important Notice About Information Presented in This Prospectus
   and the Applicable Prospectus Supplement....................................6

Summary of Prospectus..........................................................7

Risk Factors..................................................................12
   Limited Liquidity for Certificates.........................................12
   Limited Assets for Payment of Certificates.................................12
   Certificates May Not Be Appropriate For Certain Individual
      Investors...............................................................12
   Credit Enhancement is Limited in Amount and Coverage.......................13
   The Ratings of Your Certificates May Be Lowered or Withdrawn
      Which May Adversely Affect the Liquidity or Market Value
      of Your Certificates....................................................13
   Real Estate Market Conditions Affect Mortgage Loan Performance.............14
   Geographic Concentration May Increase Rates of Loss and
      Delinquency.............................................................14
   Mortgage Loans May Experience Greater Rates of Delinquency
      and Foreclosure Due to Underwriting Standards...........................15
   Rate of Prepayment on Mortgage Assets May Adversely Affect
      Average Lives and Yields on Certificates................................15
   Modification of a Mortgage Loan May Adversely Affect the
      Certificates............................................................16
   There Is a Risk that Interest Payments on the Mortgage Loans
      May Be Insufficient to Pay Interest on Your Certificates................16
   Increase in Index May Adversely Affect Yield on Certain
      Certificates of a Series................................................17
   The Weighted Average Life of a Companion Certificate is
      Particularly Sensitive to Prepayments...................................17
   Subordination of Super Senior Support Certificates and
      Subordinated Certificates Increases Risk of Loss........................17
   There Are Risks Relating to Second Lien Mortgage Loans.....................17
   The Inclusion of "Negative Amortization" Mortgage Loans in a
      Series May Adversely Affect Yield of Related Certificates...............18
   The Inclusion of Subsidy Mortgage Loans in a Series May
      Adversely Affect Yield of the Related Certificates......................19
   The Inclusion of Buy-Down Mortgage Loans in a Series May
      Adversely Affect Yield of the Related Certificates......................19
   Balloon Loans May Have a Greater Default Risk at Maturity..................19
   Collateral Securing Cooperative Loans May Diminish in Value................20
   Leaseholds May Be Subject to Default Risk on the Underlying
      Lease...................................................................20
   Exercise of Rights Under Special Servicing Agreements May Be
      Adverse to Other Certificateholders.....................................20
   Special Powers of the FDIC in the Event of Insolvency of the
      Sponsor Could Delay or Reduce Distributions on the
      Certificates............................................................21
   Insolvency of the Depositor May Delay or Reduce Collections
      on Mortgage Loans.......................................................22
   Book-Entry Certificates May Experience Decreased Liquidity
      and Payment Delay.......................................................22
   Cash Flow Agreements and External Credit Enhancements are
      Subject to Third Party Risk.............................................23
   Servicing Transfer Following Event of Default May Result in
      Payment Delays or Losses................................................23
   Consumer Protection Laws May Limit Remedies................................23
   The Recording of the Mortgages of a Series in the Name of
      MERS May Affect the Yield on the Certificates...........................24

The Trust Estates.............................................................24
   General....................................................................24
   Mortgage Loans.............................................................25
   Mortgage Certificates......................................................30
   Cash Flow Agreements.......................................................31
      General.................................................................31
      Guaranteed Investment Contract..........................................31
      Yield Maintenance Agreements............................................32
      Swap Agreements.........................................................32

2

The Sponsor...................................................................32

Wells Fargo Bank's Mortgage Loan Programs.....................................35
   Mortgage Loan Production Sources...........................................35
   Acquisition of Mortgage Loans from Correspondents..........................36
   Mortgage Loan Underwriting.................................................37
      General.................................................................37
      Retention Program.......................................................41
      Non-Agency Conduit Program..............................................42
      Role of Loan Underwriter Discretion.....................................42
      Alt-A Mortgage Loans....................................................42

Static Pool Information.......................................................52

The Depositor.................................................................52

Description of the Certificates...............................................54
   General....................................................................54
   Definitive Form............................................................54
   Book-Entry Form............................................................55
      General.................................................................55
      Secondary Market Trading................................................58
      Certain U.S. Federal Income Tax Documentation Requirements
         of Book-Entry Certificates...........................................60
   Distributions to Certificateholders........................................60
      General.................................................................60
      Unscheduled Principal Receipts..........................................62
      Distributions of Interest...............................................63
      Distributions of Principal..............................................65
   Categories of Classes of Certificates......................................65
      Principal Types.........................................................65
      Interest Types..........................................................67
   Pass-Through Rates Based on LIBOR..........................................67
      General.................................................................67
      Determination of LIBOR..................................................67
   Subordination..............................................................68
   Other Credit Enhancement...................................................70
      General.................................................................70
      Limited Guarantee.......................................................70
      Financial Guaranty Insurance Policy or Surety Bond......................70
      Letter of Credit........................................................70
      Pool Insurance Policy...................................................71
      Special Hazard Insurance Policy.........................................72
      Mortgagor Bankruptcy Bond...............................................72
      Reserve Fund............................................................73
      Cross Collateralization.................................................73
      Overcollateralization...................................................73
      Excess Interest.........................................................74
   Exchangeable Certificates..................................................74
      General.................................................................74
      Exchanges...............................................................74
      Procedures..............................................................76

Prepayment and Yield Considerations...........................................76
   Pass-Through Rates.........................................................76
   Effects of Defaults........................................................77
   Scheduled Delays in Distributions..........................................77
   Effect of Principal Prepayments............................................77
   Weighted Average Life of Certificates......................................77
   Refinancings...............................................................79

Servicing of the Mortgage Loans...............................................80
   The Master Servicer........................................................80
      General.................................................................80
      Master Servicing Experience and Procedures of Wells Fargo
         Bank.................................................................82
   The Servicers..............................................................83
   Servicing Experience and Procedures of Wells Fargo Bank....................84
      Servicing Experience....................................................84
      Servicing Procedures....................................................85
   Payments on Mortgage Loans.................................................87
   Periodic Advances and Limitations Thereon..................................90
   PMI Advances...............................................................91
   Collection and Other Servicing Obligations.................................91
   Enforcement of Due-on-Sale Clauses; Realization Upon
      Defaulted Mortgage Loans................................................91
   Insurance Policies.........................................................93
      Standard Hazard Insurance Policies......................................93
      Primary Mortgage Insurance Policies.....................................94
   Fixed Retained Yield, Servicing Compensation and Payment of
      Expenses................................................................95
   Evidence as to Compliance..................................................95
   Changes in Servicing.......................................................96
      Changes in Timing of Remittances of Unscheduled Principal
         Receipts in Full and Elimination of Month End Interest...............96
      Changes in Unscheduled Principal Receipt Period.........................96
   Servicer Defaults..........................................................97

The Pooling and Servicing Agreement...........................................97
   Assignment of Mortgage Loans to the Trustee................................97
   Representations and Warranties.............................................99
   Optional Purchases........................................................100
   Reports to Certificateholders.............................................100
   List of Certificateholders................................................102
   Events of Default.........................................................102
   Rights Upon Event of Default..............................................103
   Amendment.................................................................104

3

   Termination; Optional Purchase of Mortgage Loans..........................104
   The Trustee...............................................................105
   The Custodian.............................................................106
   Special Servicing Agreements..............................................106

The Trust Agreement..........................................................107
   Assignment of Mortgage Certificates to the Trustee........................107
   Representations and Warranties............................................107
   Payments on Mortgage Certificates.........................................108
   Reports to Certificateholders.............................................110
   List of Certificateholders................................................111
   Events of Default.........................................................111
   Rights Upon Event of Default..............................................111
   Amendment.................................................................112
   Termination; Optional Purchase of Mortgage Certificates...................113
   The Securities Administrator..............................................114
      General................................................................114
      Securities Administration Experience and Procedures of
         Wells Fargo Bank....................................................116
   Evidence as to Compliance.................................................116
   The Trustee...............................................................116

Certain Legal Aspects of the Mortgage Loans..................................117
   General...................................................................117
   Condominiums..............................................................118
   Cooperatives..............................................................118
   Foreclosure...............................................................118
   Foreclosure on Shares of Cooperatives.....................................119
   Leaseholds................................................................120
   Rights of Redemption......................................................120
   Anti-Deficiency Legislation, the Bankruptcy Code and Other
      Limitations on Lenders.................................................121
   Forfeiture for Drug, RICO and Money Laundering Violations.................122
   Homeowners Protection Act of 1998.........................................123
   Texas Home Equity Loans...................................................123
   Servicemembers Civil Relief Act and Similar Laws..........................123
   Environmental Considerations..............................................124
   "Due-on-Sale" Clauses.....................................................126
   Applicability of Usury Laws...............................................126
   Enforceability of Certain Provisions......................................127

Material Federal Income Tax Consequences.....................................127
   Federal Income Tax Consequences for REMIC Certificates....................128
      General................................................................128
      Status of REMIC Certificates...........................................128
      Qualification as a REMIC...............................................129
      Taxation of Regular Certificates.......................................130
      Taxation of Residual Certificates......................................136
      Taxes That May Be Imposed on the REMIC Pool............................143
      Liquidation of the REMIC Pool..........................................144
      Administrative Matters.................................................144
      Limitations on Deduction of Certain Expenses...........................144
      Taxation of Certain Foreign Investors..................................145
      Backup Withholding.....................................................146
      Reporting Requirements.................................................146
   Federal Income Tax Consequences for Certificates as to Which
      No REMIC Election Is Made..............................................146
      General................................................................146
      Tax Status.............................................................147
   Premium and Discount......................................................148
      Premium................................................................148
      Original Issue Discount................................................148
      Market Discount........................................................148
   Recharacterization of Servicing Fees......................................148
   Sale or Exchange of Certificates..........................................149
   Stripped Certificates.....................................................149
      General................................................................149
      Status of Stripped Certificates........................................150
      Taxation of Stripped Certificates......................................151
   Reporting Requirements and Backup Withholding.............................152
   Taxation of Certain Foreign Investors.....................................153
   Federal Income Tax Consequences for Exchangeable Certificates.............153
      Tax Status.............................................................153
      Exchangeable Certificates Representing Proportionate
         Interests in Two or More Exchangeable REMIC Certificates............153
      Exchangeable Certificates Representing Disproportionate
         Interests in Exchangeable REMIC Certificates........................153
      Sales, Exchanges and Other Dispositions of Exchangeable
         Certificates........................................................154

ERISA Considerations.........................................................154
   General...................................................................154
   Certain Requirements Under ERISA..........................................155
      General................................................................155
      Parties in Interest/Disqualified Persons...............................155
      Delegation of Fiduciary Duty...........................................155
   Administrative Exemptions.................................................156
      Individual Administrative Exemptions...................................156
      PTE 83-1...............................................................157
   Exempt Plans..............................................................158

4

   Unrelated Business Taxable Income-Residual Certificates...................158

Legal Investment.............................................................158

Accounting Considerations....................................................160

Plan of Distribution.........................................................160

Use of Proceeds..............................................................161

Legal Matters................................................................161

Rating.......................................................................161

Reports to Certificateholders................................................161

Where You Can Find More Information..........................................162

Incorporation of Certain Information by Reference............................162

Index of Prospectus Definitions..............................................164

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IMPORTANT NOTICE ABOUT INFORMATION PRESENTED IN THIS
PROSPECTUS AND THE APPLICABLE PROSPECTUS SUPPLEMENT

Information is provided to you about the certificates in two separate documents that progressively provide more detail: (a) this prospectus, which provides general information, some of which may not apply to a particular series of certificates, including your series, and (b) the applicable prospectus supplement, which will describe the specific terms of your series of certificates, including:

o the principal balances and/or interest rates of each class;

o the timing and priority of interest and principal payments;

o statistical and other information about the mortgage loans;

o information about credit enhancement, if any, for each class;

o the ratings for each class; and

o the method for selling the certificates.

You should rely only on the information provided in this prospectus and the applicable prospectus supplement including the information incorporated by reference. No one has been authorized to provide you with different information. The certificates are not being offered in any state where the offer is not permitted. The depositor does not claim the accuracy of the information in this prospectus or the applicable prospectus supplement as of any date other than the dates stated on their respective covers.

Cross-references are included in this prospectus and in the applicable prospectus supplement to captions in these materials where you can find further related discussions. The foregoing table of contents and the table of contents included in the applicable prospectus supplement provide the pages on which these captions are located.

You can find a listing of the pages where capitalized terms used in this prospectus are defined under the caption "Index of Prospectus Definitions" beginning on page 164 in this prospectus.

The depositor's principal executive office is located at 8480 Stagecoach Circle, Frederick, MD 21701, and the depositor's telephone number is (240) 586-5999.


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SUMMARY OF PROSPECTUS

o This summary highlights selected information from this document, but does not contain all of the information that you should consider in making your investment decision. To understand all of the terms of a series of certificates, please read this entire document and the applicable prospectus supplement carefully.

o This summary provides an overview of certain calculations, cash flows and other information to aid your understanding of the terms of the certificates and is qualified by the full description of these calculations, cash flows and other information in this prospectus and the applicable prospectus supplement.

RELEVANT PARTIES FOR EACH SERIES OF CERTIFICATES

Issuing Entity

Each series of certificates will be issued by a separate common law trust. Each trust will be formed, and each series of certificates will be issued, under a separate pooling and servicing agreement or trust agreement as specified in the applicable prospectus supplement.

Sponsor

Wells Fargo Bank, N.A. will be the sponsor of each series of certificates issued by a trust containing mortgage loans. The mortgage loans will either be originated by Wells Fargo Bank, N.A. or purchased by Wells Fargo Bank, N.A. from various entities that originated the mortgage loans to Wells Fargo Bank, N.A.'s underwriting standards or as otherwise specified in the prospectus supplement. Wells Fargo Bank, N.A. will sell the mortgage loans to the depositor on the closing date specified in the applicable prospectus supplement by means of a mortgage loan purchase agreement between Wells Fargo Bank, N.A. and the depositor.

Wells Fargo Bank, N.A. or another entity named in the prospectus supplement will be the sponsor of each series of certificates issued by a trust containing mortgage certificates. The sponsor named in the prospectus supplement will sell the mortgage certificates to the depositor on the closing date specified in such prospectus supplement by means of a mortgage certificate purchase agreement between the sponsor and the depositor.

Depositor

Wells Fargo Asset Securities Corporation will act as depositor for each series of certificates. The depositor will acquire the mortgage loans and/or mortgage certificates from the sponsor and will transfer the applicable mortgage assets to each trust. The depositor is a direct, wholly-owned subsidiary of Wells Fargo Bank, N.A. which is an indirect, wholly-owned subsidiary of Wells Fargo & Company. It is not expected that the depositor will have any business operations other than offering certificates and related activities.

Master Servicer

Wells Fargo Bank, N.A. will act as master servicer of each trust containing mortgage loans and will supervise the servicers and perform certain other administrative and reporting duties with respect to each series of certificates issued by a trust containing mortgage loans. In addition, the master servicer will generally be required to make advances with respect to the mortgage loans in each applicable trust to the extent that a servicer (other than Wells Fargo Bank, N.A.) fails to make a required advance.

Securities Administrator

To the extent specified in the applicable prospectus supplement, Wells Fargo Bank, N.A. will act as securities administrator of a trust. The securities administrator may perform general administrative and reporting duties on behalf of the trust for a series.

Servicers

Wells Fargo Bank, N.A. and, if specified in the applicable prospectus supplement, one or more other entities will service the mortgage loans in each trust containing mortgage loans. Each servicer will perform certain servicing functions with respect to the mortgage loans serviced by it pursuant to a related servicing agreement.

Trustee

A trustee for each trust will be named in the applicable prospectus supplement. The trustee generally will be responsible under the related

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agreement for providing general administrative services on behalf of the trust for a series. To the extent specified in the applicable prospectus supplement, a securities administrator may perform certain of the duties of the trustee.

Paying Agent

A paying agent for each trust will be named in the applicable prospectus supplement. The paying agent generally will be responsible under the related agreement for making distributions to certificateholders of a series.

Custodian

Wells Fargo Bank, N.A. or another entity (which may be the trustee) named in the applicable prospectus supplement will act as custodian for each series of certificates issued by a trust containing mortgage loans. Generally, the custodian will be responsible for holding and safeguarding the mortgage notes and other contents of the mortgage file on behalf of the certificateholders of a series.

THE MORTGAGE ASSETS

The assets included in each trust estate will be mortgage loans and/or mortgage certificates. Mortgage loans and mortgage certificates will collectively be referred to herein as mortgage assets.

The Mortgage Loans

Each trust containing mortgage loans will own the related mortgage loans (other than the fixed retained yield which is the portion of the mortgage interest rate, if any, not contained in the trust) and certain other related property, as specified in the applicable prospectus supplement.

The mortgage loans in each trust estate:

o will be fixed or adjustable interest rate, mortgage loans secured by first liens on one- to four-family residential properties;

o will have been acquired by the depositor from Wells Fargo Bank, N.A.;

o will have been originated by Wells Fargo Bank, N.A. or an affiliate or will have been acquired by Wells Fargo Bank, N.A. directly or indirectly from other mortgage loan originators; and

o will have been underwritten either to Wells Fargo Bank, N.A.'s general or alternative standards or to other standards specified in the applicable prospectus supplement.

See "The Trust Estates" and "Wells Fargo Bank's Mortgage Loan Programs--Mortgage Loan Underwriting."

You should refer to the applicable prospectus supplement for the precise characteristics or expected characteristics of the mortgage loans included in a particular trust estate.

The Mortgage Certificates

Each trust containing mortgage certificates will own the related mortgage certificates and certain other related property, as specified in the applicable prospectus supplement.

Each mortgage certificate will represent an interest in a pool or pools of mortgage loans and the right to receive payments of principal and/or interest on the mortgage loans. The related prospectus supplement will describe the mortgage certificates for a series in detail including the underlying mortgage loans and any credit enhancement for the mortgage certificates.

The mortgage certificates represent interests in a pool or pools of mortgage loans comprising the assets of one or more trusts established by the depositor. Therefore, any discussions in this prospectus relating to the mortgage loans underlying any series of certificates will also apply to the mortgage loans underlying a series of mortgage certificates and discussions in this prospectus relating to a series of certificates will also be applicable to such mortgage certificates.

DISTRIBUTIONS ON THE CERTIFICATES

Each series of certificates will include one or more classes. A class of certificates will be entitled, to the extent of funds available, to receive distributions from collections on the related mortgage assets and, to the extent specified in the applicable prospectus supplement, from any credit enhancements or cash flow agreements described in this prospectus.

Interest Distributions

With respect to each series of certificates, interest on the related mortgage assets at the weighted average of their mortgage interest rates or pass-through rates, as applicable, after deducting any servicing fees, administrative fees and certain other amounts as described in this prospectus or in the applicable prospectus supplement, will be passed through to

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holders of the related classes of certificates in accordance with the particular terms of each class of certificates. The terms of each class of certificates will be described in the applicable prospectus supplement. See "Description of the Certificates--Distributions to Certificateholders--Distributions of Interest."

Except as otherwise specified in the applicable prospectus supplement, interest on each class of certificates of each series will accrue at the pass-through rate for each class indicated in the applicable prospectus supplement on their outstanding principal balance or notional amount.

Principal Distributions

With respect to a series of certificates, principal payments (including prepayments) on the related mortgage assets will be passed through to holders of the related certificates or otherwise applied in accordance with the related agreement on each distribution date. Distributions in reduction of principal balance will be allocated among the classes of certificates of a series in the manner specified in the applicable prospectus supplement. See "Description of the Certificates--Distributions to Certificateholders--Distributions of Principal."

Distribution Dates

Distributions on the certificates will be made on each distribution date which is generally the 25th day of each month, or, if such day is not a business day, the business day following the 25th day. If so specified in the applicable prospectus supplement, distributions on certificates may be made on a different day of each month or may be made quarterly, or semi-annually, on the dates specified in such prospectus supplement. The cut-off date, if any, for each series will be the date specified in the applicable prospectus supplement.

Record Dates

Distributions will be made on each distribution date to certificateholders of record at the close of business on the last business day of the month preceding the month in which such distribution date occurs (unless a different date is specified in the applicable prospectus supplement).

CREDIT ENHANCEMENT

Subordination

A series of certificates may include one or more classes of senior certificates and one or more classes of subordinated certificates. The rights of the holders of subordinated certificates of a series to receive distributions will be subordinated to such rights of the holders of the senior certificates of the same series to the extent and in the manner specified in the applicable prospectus supplement.

Subordination is intended to enhance the likelihood of the timely receipt by the senior certificateholders of their proportionate share of scheduled monthly principal and interest payments on the related mortgage assets and to protect them from losses. This protection will be effected by:

o the preferential right of the senior certificateholders to receive, prior to any distribution being made in respect of the related subordinated certificates on each distribution date, current distributions on the related mortgage assets of principal and interest due them on each distribution date out of the funds available for distributions on such date;

o the right of such holders to receive future distributions on the mortgage assets that would otherwise have been payable to the holders of subordinated certificates; and/or

o the prior allocation to the subordinated certificates of all or a portion of losses realized on the underlying mortgage assets.

Other Types of Credit Enhancement

If so specified in the applicable prospectus supplement, the certificates of any series, or any one or more classes of a series, may, in addition to or in lieu of subordination, be entitled to the benefits of one or more of the following types of credit enhancement:

o limited guarantee o letter of credit

o financial guaranty o reserve fund

o insurance policy o cross-collateralization

o surety bond o overcollateralization

o mortgage pool insurance policy o excess interest

See "Description of the Certificates--Other Credit Enhancement." In addition, if specified in the

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applicable prospectus supplement, amounts received under any cash flow agreement described under "The Trust Estate--Cash Flow Agreements" may also be used to provide credit enhancement for one or more classes of certificates.

PERIODIC ADVANCES ON DELINQUENT PAYMENTS

In the event that a payment on a mortgage loan is delinquent, the servicer of the mortgage loan will be obligated, to the extent specified in the related servicing agreement, to make cash advances if the servicer determines that it will be able to recover such amounts from future payments and collections on the mortgage loan. A servicer who makes periodic advances will be reimbursed for these as described in this prospectus and in the applicable prospectus supplement. If the servicer fails to make a required principal or interest advance, the master servicer or trustee will be required to make these advances from its own funds, unless such party determines that it will not be able to recover those amounts from future payments and collections on the mortgage loans.

See "Servicing of the Mortgage Loans--Periodic Advances and Limitations Thereon."

FORMS OF CERTIFICATES

The certificates will be issued either:

o in book-entry form through the facilities of DTC; or

o in fully registered, certificated form.

If you own book-entry certificates, you will not receive a physical certificate representing your ownership interest in such book-entry certificates, except under extraordinary circumstances which are discussed in "Description of the Certificates--Book-Entry Form" in this prospectus. Instead, DTC will effect payments and transfers by means of its electronic record keeping services, acting through certain participating organizations. This may result in certain delays in your receipt of distributions and may restrict your ability to pledge your securities. Your rights with respect to book-entry certificates may generally only be exercised through DTC and its participating organizations.

See "Description of the Certificates--Book-Entry Form."

OPTIONAL PURCHASE OF CERTAIN MORTGAGE LOANS

If so specified in the prospectus supplement for a series issued by a trust containing mortgage loans, the depositor may, subject to the terms of the applicable pooling and servicing agreement, purchase from the related trust:

o any defaulted mortgage loan during the periods specified under "The Pooling and Servicing Agreement--Optional Purchases"; and

o any defaulted mortgage loan or mortgage loan as to which default is reasonably foreseeable as to which the originator of such mortgage loan breached a representation or warranty to Wells Fargo Bank, N.A., as sponsor, regarding the characteristics of such mortgage loan.

See "The Pooling and Servicing Agreement--Optional Purchases."

OPTIONAL PURCHASE OF ALL MORTGAGE ASSETS AND TERMINATION OF THE TRUST

If so specified in the prospectus supplement with respect to a series, all of the mortgage assets in the related trust (or one or more groups of mortgage assets, if specified in the applicable prospectus supplement) and any property acquired with respect to such mortgage assets may be purchased by the depositor, the sponsor of such series or such other party as is specified in the applicable prospectus supplement. Any such purchase must be made in the manner and at the price specified in "The Pooling and Servicing Agreement----Termination; Optional Purchase of Mortgage Loans" or "The Trust Agreement--Termination; Optional Purchase of Mortgage Certificates," as applicable.

In the event that an election is made to treat the related trust estate or one or more segregated pools of assets in the trust estate as a REMIC, any such purchase will be effected only pursuant to a "qualified liquidation," as defined under Section 860F(a)(4)(A) of the Internal Revenue Code of 1986, as amended.

Exercise of the right of purchase will effect the early retirement of the certificates of that series.

See "Prepayment and Yield Considerations."

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ERISA LIMITATIONS

If you are a fiduciary of any employee benefit plan subject to the fiduciary responsibility or prohibited transaction provisions of ERISA, you should carefully review with your own legal advisors whether the purchase or holding of certificates could give rise to a transaction prohibited or otherwise impermissible under ERISA or other similar rules or regulations.

See "ERISA Considerations."

TAX STATUS

The treatment of the certificates for federal income tax purposes will depend on:

o whether a REMIC election is made with respect to a series of certificates; and

o if a REMIC election is made, whether the certificates are regular interests or residual interests.

If one or more REMIC elections are made, certificates that are regular interests will be treated as newly issued debt instruments of the REMIC and must be accounted for under an accrual method of accounting. Certificates that are residual interests are not treated as debt instruments, but rather must be treated according to the rules prescribed in the Internal Revenue Code for REMIC residual interests, including restrictions on transfer and the reporting of net income or loss of the REMIC, including the possibility of a holder of such certificate having taxable income without a corresponding distribution of cash to pay taxes currently due.

If the certificates represent interests in a grantor trust, beneficial owners of certificates generally are treated as owning an undivided beneficial interest in the mortgage loans that are assets of the trust.

See "Material Federal Income Tax Consequences."

LEGAL INVESTMENT

The applicable prospectus supplement will specify whether the class or classes of certificates offered will constitute "mortgage related securities" for purposes of the Secondary Mortgage Market Enhancement Act of 1984, as amended. If your investment authority is subject to legal restrictions you should consult your own legal advisors to determine whether and to what extent such certificates constitute legal investments for you.

See "Legal Investment" in this prospectus and in the applicable prospectus supplement.

RATING

Certificates of any series will not be offered pursuant to this prospectus and a prospectus supplement unless each offered class is rated in one of the four highest rating categories by at least one nationally recognized statistical rating organization.

o A security rating is not a recommendation to buy, sell or hold the certificates of any series and is subject to revision or withdrawal at any time by the assigning rating agency.

o Ratings do not address the effect of prepayments on the yield you may anticipate when you purchase your certificates.

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RISK FACTORS

You should consider, among other things, the following factors in connection with the purchase of certificates. Any risk described with respect to certificates backed by mortgage loans will also be applicable to a series backed by those mortgage certificates.

Limited Liquidity for Certificates

The liquidity of your certificates may be limited. You should consider that:

o a secondary market for the certificates of any series may not develop, or if it does, it may not provide you with liquidity of investment, or it may not continue for the life of the certificates of any series;

o the prospectus supplement for any series of certificates may indicate that an underwriter intends to establish a secondary market in such certificates, but no underwriter will be obligated to do so; and

o unless specified in the applicable prospectus supplement, the certificates will not be listed on any securities exchange.

In addition to these considerations, the secondary market for mortgage-backed securities has experienced periods of illiquidity and may do so in the future. Illiquidity means that there may not be any purchasers for your class of certificates. Although any class of certificates may experience illiquidity, it is more likely that classes of certificates that are more sensitive to prepayment, credit or interest rate risk will experience illiquidity. You should consider that illiquidity may also result from legal or regulatory changes, or from the adoption or change of accounting rules, which affect the certificates generally or particular types of certificateholders.

Limited Assets for Payment of Certificates

Except for any related insurance policies and any reserve fund or credit enhancement described in the applicable prospectus supplement:

o mortgage assets included in the related trust estate will be the sole source of payments on the certificates of a series;

o the certificates of any series will not represent an interest in or obligation of the depositor, the sponsor, the master servicer, the securities administrator, the paying agent, any servicer, the trustee or any of their affiliates, except for the depositor's limited obligations with respect to certain breaches of its representations and warranties, limited obligations of a servicer with respect to its servicing obligations and limited obligations of the master servicer with respect to its master servicing obligations; and

o neither the certificates of any series nor the related mortgage assets will be guaranteed or insured by any governmental agency or instrumentality, the depositor, the sponsor, the master servicer, the securities administrator, the paying agent, any servicer, the trustee, any of their affiliates or any other person.

Consequently, in the event that payments on the mortgage assets underlying your series of certificates are insufficient or otherwise unavailable to make all payments required on your certificates, there will be no recourse to the depositor, the sponsor, the master servicer, the securities administrator, any servicer, the trustee, the paying agent or, except as specified in the applicable prospectus supplement, any other entity.

Certificates May Not Be Appropriate For Certain Individual Investors

If you are an individual investor who does not have sufficient resources or expertise to evaluate the particular characteristics of a series of certificates, the series of certificates may not be an appropriate investment for you. This may be the case because, among other things:

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o if you purchase your certificates at a price other than par, your yield to maturity will be sensitive to the uncertain rate and timing of principal prepayments on the applicable mortgage loans;

o the rate of principal distributions on, and the weighted average life of, the certificates will be sensitive to the uncertain rate and timing of principal prepayments on the applicable mortgage loans and the priority of principal distributions among the classes of certificates of such series, and, as such, the certificates may be inappropriate investments for you if you require a distribution of a particular amount of principal on a specific date or an otherwise predictable stream of distributions;

o you may not be able to reinvest amounts distributed in respect of principal on your certificates (which distributions in general, are expected to be greater during periods of relatively low interest rates) at a rate at least as high as the applicable pass-through rate or your expected yield;

o a secondary market for the certificates may not develop or provide you with liquidity of investment; and

o you must report interest as well as original issue discount, if any, on the accrual method of accounting, even if you are otherwise using the cash method of accounting.

If you are an individual investor considering the purchase of a certificate of a series, you should carefully consider other risk factors discussed in this prospectus and the applicable prospectus supplement.

Credit Enhancement is Limited in Amount and Coverage

With respect to each series of certificates, credit enhancement may be provided in limited amounts to cover certain types of losses on the underlying mortgage assets. Credit enhancement will be provided in one or more of the forms referred to in this prospectus, including: subordination of other classes of certificates of the same series; a limited guarantee; a financial guaranty insurance policy; a surety bond; a letter of credit; a pool insurance policy; a special hazard insurance policy; a mortgagor bankruptcy bond; a reserve fund; cross-collateralization; overcollateralization; excess interest; and any combination of the preceding types of credit enhancement. To the extent that a trust estate contains mortgage certificates, credit enhancement may be provided solely by virtue of the provision of one or more of the preceding types of credit enhancement to the underlying mortgage certificates. See "Description of the Certificates--Other Credit Enhancement."

Regardless of the form of credit enhancement provided:

o the amount of coverage will be limited in amount and in most cases will be subject to periodic reduction in accordance with a schedule or formula; and

o may provide only very limited coverage as to certain types of losses, and may provide no coverage as to certain other types of losses.

In the event losses exceed the amount of coverage provided by any credit enhancement or losses of a type not covered by any credit enhancement occur, such losses will be borne by the holders of the related certificates (or certain classes).

None of the depositor, the sponsor, the master servicer, the securities administrator, any servicer, the paying agent nor any of their affiliates will have any obligation to replace or supplement any credit enhancement, or to take any other action to maintain any rating of any class of certificates of such series.

See "Description of the Certificates--Other Credit Enhancement."

The Ratings of Your Certificates May Be Lowered or Withdrawn Which May Adversely Affect the Liquidity or Market Value of Your Certificates

It is a condition to the issuance of the certificates of a series offered by a prospectus supplement that the certificates be rated in one of the four highest rating categories by a nationally recognized statistical rating agency. A security rating is not a recommendation to buy, sell or hold securities and may be subject to revision or

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withdrawal at any time. No person is obligated to maintain the rating on any certificate, and accordingly, there can be no assurance to you that the ratings assigned to any certificate on the date on which the certificate is originally issued will not be lowered or withdrawn by a rating agency at any time thereafter. The rating(s) of any series of certificates by any applicable rating agency may be lowered following the initial issuance of the certificates as a result of the downgrading of the obligations of any applicable credit support provider, or as a result of losses on the related mortgage assets in excess of the levels contemplated by the rating agency at the time of its initial rating analysis or, in the case of a series backed by mortgage certificates, as a result of a downgrading of the mortgage certificates. Neither the depositor nor the sponsor nor any of their respective affiliates will have any obligation to replace or supplement any credit support, or to take any other action to maintain any rating(s) of such series of certificates. If any rating is revised or withdrawn, the liquidity or the market value of your certificate may be adversely affected.

Real Estate Market Conditions Affect Mortgage Loan Performance

An investment in securities such as the certificates, which generally represent interests in pools of residential mortgage loans or mortgage certificates backed by pools of residential mortgage loans, may be affected by a decline in real estate values and changes in the mortgagor's financial condition. There is no assurance that the values of the mortgaged properties securing the mortgage loans underlying any series of certificates have remained or will remain at their levels on the dates of origination of the related mortgage loans.

If the residential real estate market should experience an overall decline in property values such that the outstanding balances of the mortgage loans underlying a series and any secondary financing on the mortgaged properties, become equal to or greater than the value of the mortgaged properties, delinquencies, foreclosures and losses could be higher than those now generally experienced in the mortgage lending industry and those experienced in Wells Fargo Bank, N.A.'s or other servicers' servicing portfolios.

To the extent that losses on mortgage loans underlying a series are not covered by credit enhancement, certificateholders of the series will bear all risk of loss resulting from default by mortgagors and will have to look primarily to the value of the mortgaged properties for recovery of the outstanding principal and unpaid interest on the defaulted mortgage loans. See "The Trusts Estates--Mortgage Loans" and "Wells Fargo Bank's Mortgage Loan Programs--Mortgage Loan Underwriting."

Geographic Concentration May Increase Rates of Loss and Delinquency

In addition to risk factors related to the residential real estate market generally, certain geographic regions of the United States from time to time will experience weaker regional economic conditions and housing markets or be directly or indirectly affected by natural disasters or civil disturbances such as earthquakes, hurricanes, floods, eruptions or riots. Mortgage loans in such areas will experience higher rates of loss and delinquency than on mortgage loans generally. Although mortgaged properties located in certain identified flood zones will be required to be covered by flood insurance, to the minimum amount required by the sponsor, as described under "Servicing of the Mortgage Loans--Insurance Policies," such amount may be significantly smaller than the unpaid principal balance of the related mortgage loan. In addition, no mortgaged properties will otherwise be required to be insured against earthquake damage or any other loss not covered by standard hazard insurance policies, as described under "Servicing of the Mortgage Loans--Insurance Policies."

The ability of mortgagors to make payments on the mortgage loans may also be affected by factors which do not necessarily affect property values, such as adverse economic conditions generally, in particular geographic areas or industries, or affecting particular segments of the borrowing community (such as mortgagors relying on commission income and self-employed mortgagors). Such occurrences may accordingly affect the actual rates of delinquencies, foreclosures and losses on the mortgage loans underlying a series of certificates.

The mortgage loans underlying certain series of certificates may be concentrated in certain regions. Such concentration may present risk considerations in addition to those generally present for similar mortgage-backed securities without such concentration. See "Wells Fargo Bank's Mortgage Loan Programs--Mortgage Loan Underwriting."

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Mortgage Loans May Experience Greater Rates of Delinquency and Foreclosure

Due to Underwriting Standards

Some of the mortgage loans underlying a series of certificates may be mortgage loans that, due to borrower credit characteristics, do not meet the sponsor's general underwriting policies for "prime" mortgage loans. In addition, all or a portion of the mortgage loans underlying a series of certificates may have been originated under the sponsor's "alternative" mortgage loan underwriting program. Under the "alternative" program, certain of the mortgage loans may have been originated with reduced or no documentation, higher maximum loan-to-value ratios, lower FICO scores, less restrictive requirements for investment properties or "equity take out" financings, and may have been secured by shares in cooperative housing corporations, condotels or unique parcels of land or may have been made to foreign nationals. In addition, a portion of the mortgage loans may have been originated with no documentation or may be no ratio loans, stated loans or stated reduced loans for which ratios of the related prospective borrowers' debt service on the mortgage loan and total debt obligations to income were not required to be taken into account in making the loan or for which no information regarding income or assets was required. As a consequence of the mortgage loans being underwriting in accordance with these underwriting standards, delinquencies, foreclosures and cumulative losses may be expected to be more likely with respect to these mortgage loans than with respect to mortgage loans originated in accordance with the sponsor's "prime" underwriting guidelines.

For a description of the underwriting guidelines applicable to the mortgage loans underlying a series of securities, see "The Wells Fargo's Mortgage Loan Programs--Mortgage Loan Underwriting."

Rate of Prepayment on Mortgage Assets May Adversely Affect Average Lives and Yields on Certificates

The yield of the certificates of each series will depend in part on the rate of principal payment on the mortgage loans included in a trust estate (including prepayments, liquidations due to defaults and repurchases) or underlying the mortgage certificates included in a trust estate and, in the case of a series backed by mortgage certificates, the priority of allocations of principal payments on the underlying mortgage loans among the mortgage certificates and other certificates of the same series. Such yield may be adversely affected, depending upon whether a particular certificate is purchased at a premium or a discount, by a higher or lower than anticipated rate of prepayments on the related mortgage assets. In particular:

o the yield on classes of certificates entitling their holders primarily or exclusively to payments of interest, such as interest only certificates, or primarily or exclusively to payments of principal, such as principal only certificates, will be extremely sensitive to the rate of prepayments on the related mortgage loans; and

o the yield on certain classes of certificates may be relatively more sensitive to the rate of prepayment of specified mortgage assets than other classes of certificates.

The rate of prepayments on mortgage loans is influenced by a number of factors, including:

o prevailing mortgage market interest rates;

o local and national economic conditions;

o homeowner mobility; and

o the ability of the borrower to obtain refinancing.

In addition, your yield may be adversely affected by interest shortfalls which may result from the timing of the receipt of prepayments or liquidations to the extent that such interest shortfalls are not covered by aggregate compensating interest or other mechanisms specified in the applicable prospectus supplement. Your yield will also be adversely affected to the extent that losses on the mortgage assets in the related trust estate are allocated to your certificates and may be adversely affected to the extent of unadvanced delinquencies on the mortgage loans in the related trust (or on the mortgage loans underlying any mortgage certificates in the related trust estate). Classes of certificates identified in the applicable prospectus supplement as subordinated certificates are more likely to be affected by delinquencies and losses than other classes of certificates.

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If you are purchasing certificates at a discount, and specifically if you are purchasing principal only certificates, you should consider the risk that if principal payments on the mortgage assets or, in the case of any ratio strip certificates, the related mortgage assets, occur at a rate slower than you expected, your yield will be lower than you expected. Further information relating to yield on those certificates will be included in the applicable prospectus supplement, including a table demonstrating the particular sensitivity of any class of principal only certificates to the rate of prepayments.

If you are purchasing certificates at a premium, or are purchasing an interest only certificate, you should consider the risk that if principal payments on the mortgage assets or, in the case of any interest only certificates entitled to a portion of interest paid on certain mortgage assets with higher mortgage interest rates or pass-through rates, those mortgage assets, occur at a rate faster than you expected, your yield may be lower than you expected. If you are purchasing interest only certificates, you should consider the risk that a rapid rate of principal payments on the applicable mortgage assets could result in your failure to recover your initial investment. Further information relating to yield on those certificates will be included in the applicable prospectus supplement, including, in the case of interest only certificates, a table demonstrating the particular sensitivity of those interest only certificates to the rate of prepayments.

Modification of a Mortgage Loan May Adversely Affect the Certificates

In instances in which a mortgage loan is in default, or if default is reasonably foreseeable, the applicable servicer, if it determines it is in the best interests of the certificateholders in the aggregate for the related series, may permit a modification of the mortgage loan rather than proceeding with foreclosure. Modification may have the effect of reducing the interest rate on the mortgage loan, forgiving the payment of principal or interest or extending the final maturity date of the mortgage loan (though not beyond the final scheduled distribution date for the related certificates as set forth in the applicable prospectus supplement). Any modification of a mortgage loan to reduce the interest rate or forgive principal or interest will result in reduced collections from that mortgage loan and, to the extent not covered by the related credit support, reduced distributions or losses on one or more classes of the related certificates.

There Is a Risk that Interest Payments on the Mortgage Loans May Be Insufficient to Pay Interest on Your Certificates

When a mortgage loan is prepaid in full, the mortgagor pays interest on the amount prepaid only to the date of prepayment. Liquidation proceeds and amounts received in settlement of insurance claims are also likely to include interest only to the time of payment or settlement. When a mortgage loan is prepaid in full or in part, an interest shortfall may result depending on the timing of the receipt of the prepayment and the timing of when those prepayments are passed through to certificateholders. To partially mitigate this reduction in yield, the master servicer is required to cover a portion of the shortfall in interest collections that are attributable to prepayments in full on the mortgage loans, but only up to the amount of compensating interest for such distribution date as described under "Description of the Certificates--Distributions to Certificateholders--Distributions of Interest" in this prospectus. To the extent these shortfalls from the mortgage loans are not covered by the amount of compensating interest or other mechanisms specified in the applicable prospectus supplement, they will be allocated among the classes of interest bearing certificates issued by a trust containing mortgage loans as described in the applicable prospectus supplement under "Description of the Certificates--Interest." No comparable interest shortfall coverage will be provided by the master servicer for partial prepayments or with respect to liquidations of any mortgage loans. Any interest shortfall arising from liquidations will be covered by means of the subordination of the rights of subordinate certificateholders of a trust containing mortgage loans or any other credit support arrangements described in this prospectus. Any interest shortfall arising from partial prepayments will be allocated among the classes of interest bearing certificates as described in the applicable prospectus supplement under "Description of the Certificates--Interest."

The prospectus supplement for any series backed by mortgage certificates will describe the allocation to the related certificates of any interest shortfalls arising from the interest prepayments that have been allocated to the mortgage certificates.

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Increase in Index May Adversely Affect Yield on Certain Certificates of a Series

Certain series of certificates may contain inverse floating rate certificates. If you are purchasing inverse floating rate certificates of a series, you should consider the risk that a high rate of the applicable index may result in a lower actual yield than you expected or a negative yield. In particular, you should consider the risk that high constant rates of the applicable index or high constant prepayment rates on the mortgage loans (or on the mortgage loans underlying any mortgage certificates included in a trust estate) may result in the failure to recover your initial investment.

The particular sensitivities of the inverse floating rate certificates are separately displayed in tables in an Appendix to the applicable prospectus supplement.

See "Prepayment and Yield Considerations" in the applicable prospectus supplement.

The Weighted Average Life of a Companion Certificate is Particularly Sensitive to Prepayments

Because on any distribution date companion certificates will not receive principal distributions until the planned amortization certificates, targeted amortization certificates or scheduled certificates they support have been paid to their planned, targeted or scheduled balances, and will receive all principal distributions in excess of those required to pay the planned amortization certificates, targeted amortization certificates or scheduled certificates to their planned, targeted or scheduled balances, the weighted average life of a companion certificate of a series is particularly sensitive to principal prepayments on the mortgage loans of such series.

In addition, investors should also note that any mortgage certificates included in a trust estate could be companion certificates and therefore the certificates issued by such series will be particularly sensitive to principal prepayments on the mortgage loans underlying any mortgage certificates included in the trust estate.

Subordination of Super Senior Support Certificates and Subordinated Certificates Increases Risk of Loss

Certain series of certificates may contain super senior support certificates. If you purchase a class of super senior support certificates of a series, you should consider the risk that after the aggregate principal balance of the subordinated certificates of the series has been reduced to zero, the principal portion of realized losses allocated to the related class of super senior certificates of a series will be borne by your class of super senior support certificates (in addition to the principal portion of realized losses allocated to such class of super senior support certificates) and not by the related class of super senior certificates so long as the principal balance of such class of super senior support certificates remains outstanding. See "Description of the Certificates" in the applicable prospectus supplement.

The rights of the holders of each class of subordinated certificates of a series to receive distributions will be subordinated to such rights of the holders of the senior certificates of the series and the holders of the lower-numbered classes of subordinated certificates of the series, if any. In addition, realized losses will be allocated to the subordinated certificates of a series in the reverse order in which they are entitled to distributions of principal before being allocated to the senior certificates of a series. Accordingly, if you are purchasing subordinated certificates, you will be more likely to experience losses as a result of the occurrence of losses or interest shortfalls on the mortgage loans of the related series. See "Description of the Certificates" in the applicable prospectus supplement.

A trust containing mortgage certificates may include super senior support certificates or subordinated certificates. Therefore, while the certificates issued by such trust may not be super senior support or subordinated certificates, they may be subject to the same risks because the mortgage certificates underlying such certificates are subject to such risk.

There Are Risks Relating to Second Lien Mortgage Loans

With respect to certain of the mortgage loans of a series (or certain of the mortgage loans underlying mortgage certificates of a series), at the time of origination of the first lien mortgage loan, the originator or another lender may have originated a second lien mortgage loan. With respect to mortgage loans that have second lien mortgage loans encumbering the same mortgaged property, foreclosure frequency may be increased relative to mortgage loans that

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do not have second lien mortgage loans behind them because mortgagors have less equity in the mortgaged property. Investors should also note that any mortgagor may obtain second lien mortgage loans at any time subsequent to the date of origination of their first lien mortgage loan from the originator or from any other lender. See table with the heading "Original Combined Loan-To-Value Ratios" in Appendix A of the prospectus supplement for the certificates or, if applicable, the related mortgage certificates. To the extent known by the depositor, information relating to any second lien mortgage loans relating to the mortgage loans for a series will be specified in an appendix or exhibit to the applicable prospectus supplement containing the applicable mortgage loan information.

The Inclusion of "Negative Amortization" Mortgage Loans in a Series May Adversely Affect Yield of Related Certificates

If so specified in the applicable prospectus supplement, a trust estate (or a trust estate underlying a trust estate containing mortgage certificates) may contain "negative amortization" mortgage loans. The mortgage interest rates on mortgage loans that allow for "negative amortization" will adjust monthly but their monthly payments and amortization schedules adjust annually and are subject to payment caps. During a period of rising interest rates, as well as prior to the annual adjustment to the monthly payment made by the mortgagor, the amount of interest accruing on the principal balance of such mortgage loans may exceed the amount of the scheduled monthly payment. As a result, a portion of the accrued interest on such a mortgage loan may become "deferred interest" which will be added to the principal balance of such mortgage loan and will also bear interest at the applicable mortgage interest rate. The excess, if any, of the aggregate amount of any deferred interest on such mortgage loans over the aggregate amount of partial and full prepayments received from mortgagors on the related mortgage loans in any month will reduce the amount of interest distributable on the classes of certificates of such series identified in the applicable prospectus supplement. Because partial and full prepayments received from mortgagors on the related mortgage loans will be used to pay deferred interest to certain classes of certificates of a series, principal distributions on the certificates of such series may occur at a slower rate than if all deferred interest on the mortgage loans was allocated in reduction of current interest distributions on such certificates. In addition, due to the priority of distributions, a class of subordinate certificates may fail to receive all or part of the deferred interest allocable to it if full and partial prepayments on such mortgage loans otherwise available for such purpose are required to pay interest (other than as a result of negative amortization of such mortgage loans) or principal on more senior classes of certificates of such series due, for example, to unadvanced delinquencies or losses on the related mortgage loans.

If the mortgage interest rates on "negative amortization" mortgage loans decrease prior to their annual adjustment in monthly payment, a larger portion of the monthly payment will be applied to the unpaid principal balance of such mortgage loans, which may cause the related classes of certificates to amortize more quickly. Conversely, if the mortgage interest rates on "negative amortization" mortgage loans increase prior to their annual adjustment in monthly payment, a smaller portion of the monthly payment will be applied to the unpaid principal balance of such mortgage loans, which may cause the related classes of certificates to amortize more slowly. If the unpaid principal balance of a "negative amortization" mortgage loan exceeds the original balance of the mortgage loan by the maximum amount specified in the related mortgage note, the monthly payment due on that mortgage loan will be recast without regard to the related payment cap in order to provide for the outstanding balance of the mortgage loan to be paid in full at its maturity. In addition, on the fifth adjustment date of a "negative amortization" mortgage loan, and every fifth adjustment date thereafter and the last adjustment date prior to such mortgage loan's maturity, the monthly payment due on that mortgage loan will be recast without regard to the related payment cap in order to provide for the outstanding balance of the mortgage loan to be paid in full at its maturity by the payment of equal monthly installments. These features may affect the rate at which principal on these mortgage loans is paid and may create a greater risk of default if the borrowers are unable to pay the monthly payments on the related increased principal balances.

On each distribution date, the deferred interest on any "negative amortization" mortgage loans will be allocated to the related classes of certificates as described in the applicable prospectus supplement. Any such allocation of deferred interest could, as a result, affect the maturity of the affected classes of certificates of such series. The amount of deferred interest, if any, with respect to such mortgage loans for a given month will reduce the amount of interest collected on these mortgage loans and available to be distributed to the related classes of certificates of such series. The resulting reduction in interest collections on such mortgage loans will be offset, in part or in whole, by applying principal prepayments received on such mortgage loans to interest distributions on the related classes of

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certificates. For any distribution date, the deferred interest on such mortgage loans, net of the amount of any offsetting prepayments, will be deducted from the interest payable to the related certificates as described in the applicable prospectus supplement. The amount of the reduction of accrued interest distributable to each related class of certificates attributable to net deferred interest will be added to the principal balance of that class of certificates. Only the amount by which the principal prepayments received on such mortgage loans exceed the amount of deferred interest on the such mortgage loans will be distributed as principal to the related classes of certificates of such series in accordance with the priorities described in the applicable prospectus supplement.

For a description of "negative amortization" mortgage loans and deferred interest, see "The Trust Estates-Mortgage Loans."

The effects on the yield of any class of certificates of a series due to the inclusion of any "negative amortization" mortgage loans in the related trust estate will be further described in the related prospectus supplement.

The Inclusion of Subsidy Mortgage Loans in a Series May Adversely Affect Yield of the Related Certificates

If so specified in the applicable prospectus supplement, a trust estate (or a trust estate underlying a trust estate containing mortgage certificates) may contain subsidy loans. The monthly payments made by the related mortgagors of a subsidy loan will be less than the scheduled monthly payments on such mortgage loans with the present value of the resulting difference in payment being provided by the employer of the mortgagor.

Generally, employers may terminate subsidy programs in the event of (i) the mortgagor's death, retirement, resignation or termination of employment, (ii) the full prepayment of the subsidy loan by the mortgagor, (iii) the sale or transfer by the mortgagor of the related mortgaged property as a result of which the mortgagee is entitled to accelerate the subsidy loan pursuant to the "due-on-sale" clause contained in the mortgage, or (iv) the commencement of foreclosure proceedings or the acceptance of a deed in lieu of foreclosure. In addition, some subsidy programs provide that if prevailing market rates of interest on mortgage loans similar to a subsidy loan are less than the mortgage interest rate of such subsidy loan, the employer may request that the mortgagor refinance such subsidy loan and may terminate the related subsidy agreement if the mortgagor fails to do so. In the event that the mortgagor refinances a subsidy loan, the new loan will not be included in the trust estate and the resulting prepayment in full of the subsidy loan may adversely affect the yield on one or more classes of certificates of the related series, particularly interest only certificates or certificates purchased at a premium over their principal balance. In the event a subsidy agreement is terminated, the amount remaining in the related subsidy account will be returned to the employer, and the mortgagor will be obligated to make the full amount of all remaining scheduled payments, if any. If the related mortgagor is unable to make the full amount of all remaining scheduled payments, the yield on the related classes of certificates may be adversely affected.

For a description of subsidy loans, see "The Trust Estates-Mortgage Loans" herein.

The Inclusion of Buy-Down Mortgage Loans in a Series May Adversely Affect Yield of the Related Certificates

If so specified in the applicable prospectus supplement, a trust estate (or a trust estate underlying a trust estate containing mortgage certificates) may contain mortgage loans subject to temporary buy-down plans pursuant to which the monthly payments made by the mortgagor during the early years of the mortgage loan will be less than the scheduled monthly payments on such mortgage loan. The resulting difference in payment will be compensated for from an amount contributed by the seller of the related mortgaged property or another source, including the originator of the mortgage loan (generally on a present value basis) and placed in a custodial account by the related servicer. If the mortgagor of a mortgage loan subject to a temporary buy-down plan is unable to make the increased monthly payment after the buy-down funds are exhausted, the yield on the related class of certificates may be adversely affected.

Balloon Loans May Have a Greater Default Risk at Maturity

If so specified in the applicable prospectus supplement, a trust estate (or a trust estate underlying a trust estate containing mortgage certificates) may contain mortgage loans that provide for a lump-sum payment of the

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unamortized principal balance of the mortgage loan at maturity. See "Description of the Mortgage Loans" in the applicable prospectus supplement.

Because borrowers under this type of mortgage loan are required to make a relatively large single payment upon maturity, it is possible that the default risk associated with such mortgage loans is greater than that associated with fully-amortizing mortgage loans. The ability of a mortgagor on this type of mortgage loan to repay the mortgage loan upon maturity frequently depends upon the mortgagor's ability:

o to refinance the mortgage loan, which will be affected by a number of factors, including, without limitation, the level of mortgage interest rates available in the primary mortgage market at the time, the mortgagor's equity in the related mortgaged property, the financial condition of the mortgagor, the condition of the mortgaged property, tax law, general economic conditions and the general willingness of financial institutions and primary mortgage bankers to extend credit; or

o to sell the related mortgaged property at a price sufficient to permit the mortgagor to make the lump-sum payment.

Collateral Securing Cooperative Loans May Diminish in Value

If specified in the applicable prospectus supplement, a trust estate (or a trust estate underlying a trust estate containing mortgage certificates) may contain cooperative loans. There are certain risks that differentiate cooperative loans from other types of mortgage loans. Ordinarily, the cooperative incurs a blanket mortgage in connection with the construction or purchase of the cooperative's apartment building and the underlying land. The interests of the occupants under proprietary leases or occupancy agreements to which the cooperative is a party are generally subordinate to the interest of the holder of the blanket mortgage. If the cooperative is unable to meet the payment obligations arising under its blanket mortgage, the mortgagee holding the blanket mortgage could foreclose on that mortgage and terminate all subordinate proprietary leases and occupancy agreements. In addition, the blanket mortgage on a cooperative may provide financing in the form of a mortgage that does not fully amortize with a significant portion of principal being due in one lump sum at final maturity. The inability of the cooperative to refinance this mortgage and its consequent inability to make such final payment could lead to foreclosure by the mortgagee providing the financing. A foreclosure in either event by the holder of the blanket mortgage could eliminate or significantly diminish the value of the collateral securing the cooperative loans.

Leaseholds May Be Subject to Default Risk on the Underlying Lease

If specified in the applicable prospectus supplement, a trust estate (or a trust estate underlying a trust estate containing mortgage certificates) may contain mortgage loans that are secured by leasehold mortgages. Leasehold mortgages are subject to certain risks not associated with mortgage loans secured by a fee estate of the mortgagor. The most significant of these risks is that the ground lease creating the leasehold estate could terminate, leaving the leasehold mortgagee without its security. The ground lease may terminate, if among other reasons, the ground lessee breaches or defaults in its obligations under the ground lease or there is a bankruptcy of the ground lessee or the ground lessor. Any leasehold mortgages underlying a series of certificates will contain provisions protective of the mortgagee as described under "The Trust Estates -- Mortgage Loans," such as the right of the leasehold mortgagee to receive notices from the ground lessor of any defaults by the mortgagor and to cure those defaults, with adequate cure periods; if a default is not susceptible of cure by the leasehold mortgagee, the right to acquire the leasehold estate through foreclosure or otherwise; the ability of the ground lease to be assigned to and by the leasehold mortgagee or purchaser at a foreclosure sale and for the simultaneous release of the ground lessee's liabilities under the new lease; and the right of the leasehold mortgagee to enter into a new ground lease with the ground lessor on the same terms and conditions as the old ground lease upon a termination.

Exercise of Rights Under Special Servicing Agreements May Be Adverse to Other Certificateholders

The pooling and servicing agreement for a series issued by a trust containing mortgage loans will permit the master servicer at the direction of the depositor to enter into a special servicing agreement with an unaffiliated holder of a class of Class B Certificates or a class of securities representing interests in one or more classes of Class B Certificates and/or other subordinated mortgage pass-through certificates, pursuant to which the holder may

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instruct the master servicer to instruct the servicer, to the extent provided in the related underlying servicing agreement, to commence or delay foreclosure proceedings with respect to delinquent mortgage loans. This right is intended to permit the holder of a class of certificates that is highly sensitive to losses on the mortgage loans to attempt to mitigate losses by exercising limited power of direction over servicing activities which accelerate or delay realization of losses on the mortgage loans. Such directions may, however, be adverse to the interest of those classes of senior certificates (including certificates that are backed by mortgage certificates which are senior certificates of the related series) that are more sensitive to prepayments than to losses on the related mortgage loans. In particular, accelerating foreclosure will adversely affect the yield to maturity on interest only certificates, while delaying foreclosure will adversely affect the yield to maturity of principal only certificates.

Special Powers of the FDIC in the Event of Insolvency of the Sponsor Could Delay or Reduce Distributions on the Certificates

The mortgage assets of a trust estate will be originated or acquired by Wells Fargo Bank, N.A., a national bank whose deposits are insured to the applicable limits by the FDIC, or an entity named in the prospectus supplement which may also be a national bank whose deposits are insured to the applicable limits by the FDIC. If the sponsor is a national bank whose deposits are insured to the applicable limits by the FDIC and such sponsor becomes insolvent, is in an unsound condition or engages in violations of its bylaws or regulations applicable to it or if similar circumstances occur, the FDIC could act as conservator and, if a receiver were appointed, would act as a receiver for such sponsor. As receiver, the FDIC would have broad powers to:

o require the applicable trust, as assignee of the depositor, to go through an administrative claims procedure to establish its rights to payments collected on the mortgage assets;

o request a stay of proceedings to liquidate claims or otherwise enforce contractual and legal remedies against such sponsor, or

o with respect to a trust containing mortgage loans, repudiate without compensation Wells Fargo Bank, N.A.'s ongoing master servicing obligations under the related pooling and servicing agreement and Wells Fargo Bank, N.A.'s ongoing servicing obligations under the applicable underlying servicing agreement, such as its duty to collect and remit payments or otherwise service the mortgage loans.

If the FDIC were to take any of those actions, distributions on the certificates could be delayed or reduced.

By statute, the FDIC as conservator or receiver of a sponsor is authorized to repudiate any "contract" of such sponsor upon payment of "actual direct compensatory damages." This authority may be interpreted by the FDIC to permit it to repudiate the transfer of the mortgage assets to the depositor. Under an FDIC regulation, however, the FDIC as conservator or receiver of a bank has stated that it will not reclaim, recover or recharacterize a bank's transfer of financial assets in connection with a securitization or participation, provided that the transfer meets all conditions for sale accounting treatment under generally accepted accounting principles, other than the "legal isolation" condition as it applies to institutions for which the FDIC may be appointed as conservator or receiver, was made for adequate consideration and was not made fraudulently, in contemplation of insolvency, or with the intent to hinder, delay or defraud the bank or its creditors. For purposes of the FDIC regulation, the term securitization means, as relevant, the issuance by a special purpose entity of beneficial interests the most senior class of which at time of issuance is rated in one of the four highest categories assigned to long-term debt or in an equivalent short-term category (within either of which there may be sub-categories or gradations indicating relative standing) by one or more nationally recognized statistical rating organizations. A special purpose entity, as the term is used in the regulation, means a trust, corporation, or other entity demonstrably distinct from the insured depository institution that is primarily engaged in acquiring and holding (or transferring to another special purpose entity) financial assets, and in activities related or incidental to these actions, in connection with the issuance by the special purpose entity (or by another special purpose entity that acquires financial assets directly or indirectly from the special purpose entity) of beneficial interests. The transactions contemplated by this prospectus and the applicable prospectus supplement will be structured so that this FDIC regulation should apply to the transfer of the mortgage assets from the applicable sponsor to the depositor.

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If a condition required under the FDIC regulation, or other statutory or regulatory requirement applicable to the transaction, were found not to have been satisfied, the FDIC as conservator or receiver might refuse to recognize the sponsor's transfer of the mortgage assets to the depositor. In that event, the depositor could be limited to seeking recovery based upon its security interest in the mortgage assets. The FDIC's statutory authority has been interpreted by the FDIC and at least one court to permit the repudiation of a security interest upon payment of actual direct compensatory damages measured as of the date of conservatorship or receivership. These damages do not include damages for lost profits or opportunity, and no damages would be paid for the period between the date of conservatorship or receivership and the date of repudiation. The FDIC could delay its decision whether to recognize the sponsor's transfer of the mortgage assets for a reasonable period following its appointment as conservator or receiver for the sponsor. If the FDIC were to refuse to recognize the sponsor's transfer of the mortgage assets, distributions on the certificates could be delayed or reduced.

If the FDIC acted as receiver for Wells Fargo Bank, N.A. after its insolvency, the FDIC could prevent the termination of Wells Fargo Bank, N.A. as a master servicer or servicer of the mortgage loans contained in the related trust, even if a contractual basis for termination exists. This inability to terminate Wells Fargo Bank, N.A. as a master servicer or servicer could result in a delay or possibly a reduction in distributions on the certificates of a series (or the mortgage certificates underlying a series) to the extent Wells Fargo Bank, N.A., as master servicer or servicer, received, but did not remit to the trustee or the securities administrator, mortgage loan collections before the date of insolvency or if Wells Fargo Bank, N.A. failed to make any required advances.

Insolvency of the Depositor May Delay or Reduce Collections on Mortgage Loans

Neither the United States Bankruptcy Code nor similar applicable state laws prohibit the depositor from filing a voluntary application for relief under these laws. However, the transactions contemplated by this prospectus and the applicable prospectus supplement will be structured so that the voluntary or involuntary application for relief under the bankruptcy laws by the depositor is unlikely. The depositor is a separate, limited purpose subsidiary, the certificate of incorporation of which contains limitations on the nature of the depositor's business, including the ability to incur debt other than debt associated with the transactions contemplated by this prospectus, and restrictions on the ability of the depositor to commence voluntary or involuntary cases or proceedings under bankruptcy laws without the prior unanimous affirmative vote of all its directors (who are required to consider the interests of the depositor's creditors, in addition to the depositor's stockholders in connection the filing of a voluntary application for relief under applicable insolvency laws). Further, the transfer of the mortgage assets to the related trust will be structured so that the trustee has no recourse to the depositor, other than for breaches of representations and warranties about the mortgage assets.

If the depositor were to become the subject of a proceeding under the bankruptcy laws, a court could conclude that the transfer of the mortgage assets from the depositor to the trust should not be characterized as an absolute transfer, and accordingly, that the mortgage assets should be included as part of the depositor's estate. Under these circumstances, the bankruptcy proceeding could delay or reduce distributions on the certificates. In addition, a bankruptcy proceeding could result in the temporary disruption of distributions on the certificates of a series.

Book-Entry Certificates May Experience Decreased Liquidity and Payment Delay

Since transactions in the classes of book-entry certificates of any series generally can be effected only through DTC, DTC participants and indirect DTC participants:

o your ability to pledge book-entry certificates to someone who does not participate in the DTC system, or to otherwise act with respect to such book-entry certificates, may be limited due to the lack of a physical certificate;

o you may experience delays in your receipt of payments on book-entry certificates because distributions will be made by the paying agent on behalf of the master servicer or securities administrator, as applicable, to Cede, as nominee for DTC;

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o you may experience delays in your receipt of payments on book-entry certificates in the event of misapplication of payments by DTC, DTC participants or indirect DTC participants or bankruptcy or insolvency of those entities and your recourse will be limited to your remedies against those entities; and

o the liquidity of book-entry certificates in any secondary trading market that may develop may be limited because investors may be unwilling to purchase securities for which they cannot obtain delivery of physical certificates.

See "Description of the Certificates--Book-Entry Form."

Cash Flow Agreements and External Credit Enhancements are Subject to Third Party Risk

The assets of a trust estate may, if specified in the applicable prospectus supplement, include agreements, such as interest rate swap, cap, floor or similar agreements, which will require the provider of such instrument or counterparty to make payments to the trust estate under the circumstances described in the prospectus supplement. To the extent that payments on the certificates of the related series (or on the mortgage certificates underlying a series) depend in part on payments to be received under this type of agreement, the ability of the trust estate to make payments on the certificates will be subject to the credit risk of the counterparty.

In addition, the ratings assigned to the certificates of a series (or on the mortgage certificates underlying a series) may depend in part on the ratings assigned to the provider of certain types of external credit enhancement, such as a mortgage pool insurance policy, surety bond, financial guaranty insurance policy or limited guarantee. Any reduction in the ratings assigned to the provider of one of these types of external credit enhancement could result in the reduction of the ratings assigned to the certificates of the series. A reduction in the ratings assigned to the certificates of a series is likely to affect adversely the liquidity and market value of the certificates.

See "The Trust Estates--Cash Flow Agreements" and "Description of the Certificates--Other Credit Enhancement" herein.

Servicing Transfer Following Event of Default May Result in Payment Delays or Losses

If an event of default occurs under a pooling and servicing agreement or underlying servicing agreement for a trust containing mortgage loans, the trustee for the related series may, in its discretion or pursuant to direction from certificateholders, remove the defaulting master servicer or servicer, as applicable, and succeed to its responsibilities, or may petition a court to appoint a successor master servicer or servicer. The trustee or the successor master servicer or servicer will be entitled to reimbursement of its costs of effecting the servicing transfer from the predecessor master servicer or servicer, or from the assets of the related trust if the predecessor fails to pay. In the event that reimbursement to the trustee or the successor master servicer or servicer is made from trust assets, the resulting shortfall will be borne by holders of the related certificates. In addition, during the pendency of a servicing transfer or for some time thereafter, mortgagors of the related mortgage loans may delay making their monthly payments or may inadvertently continue making payments to the predecessor servicer, potentially resulting in delays in distributions on the related certificates.

Consumer Protection Laws May Limit Remedies

There are various federal and state laws, public policies and principles of equity that protect consumers. Among other things, these laws, policies and principles:

o regulate interest rates and other charges;

o require certain disclosures;

o require licensing of mortgage loan originators;

o require the lender to provide credit counseling and/or make affirmative determinations regarding the borrower's ability to repay the mortgage loan;

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o prohibit discriminatory lending practices;

o limit or prohibit certain mortgage loan features, such as prepayment penalties or balloon payments;

o regulate the use of consumer credit information; and

o regulate debt collection practices.

Violation of certain provisions of these laws, policies and principles:

o may limit a servicer's ability to collect all or part of the principal of or interest on the mortgage loans;

o may entitle the borrower to a refund of amounts previously paid; and

o could subject a servicer to damages and administrative sanctions.

The depositor will generally be required to repurchase any mortgage loan which, at the time of origination, did not comply with such federal and state laws or regulations, however that remedy may not be adequate to fully compensate the related trust estate. In addition, Wells Fargo Bank, N.A., as the sponsor of the related series will be required to pay to the depositor, and the depositor will be required to pay to the applicable trust, any costs or damages incurred by the related trust as a result of a violation of these laws or regulations. See "The Pooling and Servicing Agreement--Representations and Warranties."

See "Certain Legal Aspects of the Mortgage Loans."

The Recording of the Mortgages of a Series in the Name of MERS May Affect the Yield on the Certificates

The mortgages or assignments of mortgage for some of the mortgage loans in a trust may have been recorded in the name of Mortgage Electronic Registration Systems, Inc., or MERS, solely as nominee for the originator and its successors and assigns, including the applicable trust. Subsequent assignments of those mortgages are registered electronically through the MERS system. However, if MERS discontinues the MERS system and it becomes necessary to record an assignment of mortgage to the trustee of a series, any related expenses will be paid by the related trust and will reduce the amount available to make distributions on the certificates.

The recording of mortgages in the name of MERS is a relatively new practice in the mortgage lending industry. Public recording officers and others may have limited, if any, experience with lenders seeking to foreclose mortgages, assignments of which are registered with MERS. Accordingly, delays and additional costs in commencing, prosecuting and completing foreclosure proceedings and conducting foreclosure sales of the mortgaged properties could result. Those delays and the additional costs could in turn delay the distribution of liquidation proceeds to certificateholders and increase the amount of losses on the related mortgage loans.

THE TRUST ESTATES

General

The assets underlying each Series of Certificates (each, a "Trust Estate") will consist primarily of (a) fixed or adjustable interest rate, first mortgage loans ("Mortgage Loans") evidenced by promissory notes (the "Mortgage Notes") secured by mortgages, deeds of trust or other instruments creating first liens (the "Mortgages") on some or all of the following six types of property (as so secured, the "Mortgaged Properties"), to the extent set forth in the applicable prospectus supplement: (i) one- to four-family detached residences, (ii) condominium units, including those where features of the property may include maid service, a front desk or resident manager, rental pools and up to 20% of commercial space ("condotels"), (iii) units within planned unit developments,
(iv) long-term leases with respect to any of the foregoing, (v) shares issued by private non-profit housing corporations ("Cooperatives") and the related proprietary leases or occupancy agreements granting exclusive rights to occupy specified units in such Cooperatives' buildings and (vi) manufactured homes and/or (b) previously issued Certificates of a Series which are rated in one of the four highest rating categories by a Rating Agency (the "Mortgage Certificates" and, together

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with the Mortgage Loans, the "Mortgage Assets") together with payments in respect of the Mortgage Assets and certain accounts, obligations or agreements, in each case as specified in the related prospectus supplement. In addition, a Trust Estate may also include (i) amounts held from time to time in the Certificate Account, (ii) any primary mortgage insurance, hazard insurance, title insurance or other insurance policies relating to a Mortgage Loan, (iii) any property which initially secured a Mortgage Loan and which has been acquired by foreclosure or trustee's sale or deed in lieu of foreclosure or trustee's sale, (iv) if applicable, and to the extent set forth in the applicable prospectus supplement, any reserve fund or funds and (v) if applicable, and to the extent set forth in the applicable prospectus supplement, contractual obligations of any person to make payments in respect of any form of credit enhancement, any cash flow agreement or any interest subsidy agreement. A Trust Estate containing Mortgage Loans will not include the portion of interest on the Mortgage Loans which constitutes the Fixed Retained Yield, if any. See "Servicing of the Mortgage Loans--Fixed Retained Yield, Servicing Compensation and Payment of Expenses."

Mortgage Loans

The Mortgage Loans will have been acquired by the Depositor from Wells Fargo Bank. The Mortgage Loans will have been originated by Wells Fargo Bank or will have been acquired by Wells Fargo Bank from other affiliated or unaffiliated mortgage loan originators. Each Mortgage Loan will have been underwritten either to Wells Fargo Bank's general or alternative standards as set forth herein, or to such other standards set forth in the applicable prospectus supplement. See "Wells Fargo Bank's Mortgage Loan Programs--Mortgage Loan Production Sources" and "--Mortgage Loan Underwriting." The prospectus supplement for each Series will set forth the respective number and principal amounts of Mortgage Loans (i) originated by Wells Fargo Bank or its affiliates and (ii) purchased by Wells Fargo Bank or its affiliates from unaffiliated mortgage loan originators through Wells Fargo Bank's mortgage loan purchase programs. If any originator or group of affiliated originators, apart from Wells Fargo Bank and its affiliates, originated 10% or more of the aggregate principal balance of the Mortgage Loans in a Trust Estate, the applicable prospectus supplement will disclose the identity of the originator and, if such originator or group of affiliated originators originated 20% or more of the aggregate principal balance of the Mortgage Loans, the applicable prospectus supplement will provide information about the originator's form of organization and, to the extent material, a description of the originator's origination program and how long it has been engaged in originating mortgage loans of the same type.

Each of the Mortgage Loans will be secured by a Mortgage on a Mortgaged Property located in any of the 50 states, the District of Columbia or the territories of the United States. The borrowers for each of the Mortgage Loans will be natural persons or, under certain conditions, borrowers may be inter vivos revocable trusts established by natural persons.

If specified in the applicable prospectus supplement, the Mortgage Loans may be secured by leases on real property under circumstances that Wells Fargo Bank determines in its discretion are commonly acceptable to institutional mortgage investors. A Mortgage Loan secured by a lease on real property is secured not by a fee simple interest in the Mortgaged Property but rather by a lease under which the mortgagor has the right, for a specified term, to use the related real estate and the residential dwelling located on the property. Generally, a Mortgage Loan will be secured by a lease only if (i) the use of leasehold estates as security for mortgage loans is customary in the area, (ii) the lease is not subject to any prior lien that could result in termination of the lease and (iii) the term of the lease ends at least five years beyond the maturity date of the related Mortgage Loan. The provisions of each lease securing a Mortgage Loan will expressly permit (i) mortgaging of the leasehold estate, (ii) assignment of the lease without the lessor's consent and (iii) acquisition by the holder of the Mortgage, in its own or its nominee's name, of the rights of the lessee upon foreclosure or assignment in lieu of foreclosure, unless alternative arrangements provide the holder of the Mortgage with substantially similar protections. No lease will contain provisions which (i) provide for termination upon the lessee's default without the holder of the Mortgage being entitled to receive written notice of, and opportunity to cure, such default,
(ii) provide for termination in the event of damage or destruction as long as the Mortgage is in existence or (iii) prohibit the holder of the Mortgage from being insured under the hazard insurance policy or policies related to the premises.

The prospectus supplement will set forth certain information, as of the Cut-Off Date or another specified date, to the extent known to the Depositor, detailing information about the Mortgage Loans in the Trust Estate including:
(i) the geographic distribution of Mortgaged Properties, (ii) the number and aggregate unpaid principal balances of

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the Mortgage Loans by category of Mortgaged Property, (iii) the number and aggregate unpaid principal balances of the Mortgage Loans by remaining terms to maturity and the range and weighted average of remaining terms to maturity of the Mortgage Loans, (iv) the earliest and latest months of origination and the latest maturity date of the Mortgage Loans and the number and aggregate unpaid principal balances of the Mortgage Loans by year of origination, (v) the range and weighted average of current Mortgage Interest Rates borne by the Mortgage Loans and the number and aggregate unpaid principal balances of the Mortgage Loans by range of current Mortgage Interest Rates, (vi) if such Mortgage Loans have varying Net Mortgage Interest Rates, the weighted average Net Mortgage Interest Rate of the Mortgage Loans, (vii) the range and weighted average of Loan-to-Value Ratios and Combined Loan-to-Value Ratios at the time of origination of the Mortgage Loans and the number and aggregate unpaid principal balances of the Mortgage Loans by range of Loan-to-Value Ratio and Combined Loan-to-Value Ratio at the time of origination of the Mortgage Loans, (viii) the range and weighted average of unpaid principal balances of the Mortgage Loans and the number and aggregate unpaid principal balances of the Mortgage Loans by range of original principal balances, (ix) the number and aggregate unpaid principal balances of the Mortgage Loans by documentation type, (x) the number and aggregate unpaid principal balances of the Mortgage Loans by original FICO Scores for the Mortgage Loans, (xi) the number and aggregate unpaid principal balances of the Mortgage Loans by purpose of each Mortgage Loan, (xii) the number and aggregate unpaid principal balances of the Mortgage Loans by occupancy type for each Mortgage Loan, (xiii) the number and aggregate unpaid principal balances of the Mortgage Loans by debt-to-income ratio at the time of origination of the Mortgage Loans, (xiv) the range of loan age and weighted average loan age of the Mortgage Loans and (xv) if the Trust Estate contains Interest Only Mortgage Loans, the number and aggregate unpaid principal balances of the Interest Only Mortgage Loans and the remaining interest only term and weighted average remaining interest only term for the Interest Only Mortgage Loans in the Trust Estate. If the Mortgage Loans include adjustable rate Mortgage Loans, the applicable prospectus supplement will also set forth the following additional information: (i) the number and aggregate unpaid principal balances of the Mortgage Loans by range of gross margins, (ii) the number and aggregate unpaid principal balances of the Mortgage Loans by range of rate ceilings and (iii) the number and aggregate unpaid principal balances of the Mortgage Loans by months to first adjustment date.

The Mortgage Loans in a Trust will generally have monthly payments due on the first of each month (each, a "Due Date") but may, if so specified in the applicable prospectus supplement, have payments due on a different day of each month. Unless specified in the applicable prospectus supplement, monthly payments consisting of both principal and interest will be due on each Mortgage Loan in a Trust. Each Mortgage Loan will be of one of the following types of mortgage loans:

a. Fixed Rate Loans. If so specified in the applicable prospectus supplement, a Trust Estate may include fixed rate, fully-amortizing Mortgage Loans providing for level monthly payments of principal and interest and terms at origination or modification of not more than 40 years. If specified in the applicable prospectus supplement, fixed rates on certain Mortgage Loans may be converted to adjustable rates after origination of such Mortgage Loans and upon the satisfaction of other conditions specified in the applicable prospectus supplement. If so specified in the applicable prospectus supplement, the Pooling and Servicing Agreement will require the Depositor or another party identified in the applicable prospectus supplement to repurchase each such converted Mortgage Loan at the price set forth in the applicable prospectus supplement. A Trust Estate containing fixed rate Mortgage Loans may contain convertible Mortgage Loans which have converted from an adjustable interest rate prior to the formation of the Trust Estate and which are subject to no further conversions.

b. Adjustable Rate Loans. If so specified in the applicable prospectus supplement, a Trust Estate may include adjustable rate, fully-amortizing Mortgage Loans having an original or modified term to maturity of not more than 40 years with a related Mortgage Interest Rate which generally adjusts initially either six months, one, three, five, seven or ten years subsequent to the initial Due Date, and thereafter at either six-month, one-year or other intervals over the term of the Mortgage Loan to equal the sum of a fixed margin set forth in the related Mortgage Note and an index. The applicable prospectus supplement will set forth the relevant index and the highest, lowest and weighted average margin with respect to the adjustable rate mortgage loans in the related Trust. Common indices include one-month, three-month, six-month and one-year LIBOR (an average of the interest rate on one-month, three-month, six-month or one-year dollar-denominated deposits traded between banks in London), CMT (weekly or monthly average yields of U.S. treasury short and long-term securities, adjusted to a constant maturity), COFI (an index of the weighted average interest rate paid by savings institutions in Nevada, Arizona and California), MTA (a one-year average of the monthly average yields of U.S. treasury securities) and the Prime Rate (an interest rate

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charged by banks for short-term loans to their most creditworthy customers). The applicable prospectus supplement will also indicate any initial, periodic or lifetime limitations on changes in any per annum Mortgage Rate at the time of any adjustment.

If specified in the applicable prospectus supplement, adjustable rates on certain Mortgage Loans may be converted to fixed rates after origination of such Mortgage Loans and upon the satisfaction of the conditions specified in the applicable prospectus supplement. If specified in the applicable prospectus supplement, the Depositor or another party will generally be required to repurchase each such converted Mortgage Loan at the price set forth in the applicable prospectus supplement. A Trust Estate containing adjustable rate Mortgage Loans may contain convertible Mortgage Loans which have converted from a fixed interest rate prior to the formation of the Trust Estate.

If so specified in the applicable prospectus supplement, a Trust Estate may contain adjustable rate Mortgage Loans with original terms to maturity of not more than 40 years and flexible payment options ("Option ARM Mortgage Loans"). The initial required monthly payment is fully amortizing based on the initial mortgage interest rate (which may be a rate that is less than the sum of the applicable index at origination and the gross margin specified in the related Mortgage). After an introductory period of a few months, the borrower may select from up to three payment options each month: (i) a monthly payment of principal and interest sufficient to fully amortize the mortgage loan based on the remaining scheduled term of the loan, (ii) an interest only payment that would cover solely the amount of interest that accrued during the previous month (this option is only available if it would exceed the minimum payment option for the month), or (iii) a minimum payment equal to either (a) the initial monthly payment, (b) the monthly payment as of the most recent annual adjustment date, or (c) the monthly payment as of the most recent automatic adjustment, whichever is most recent. The minimum payment adjusts annually after the first payment date but is subject to a payment cap which limits any increase or decrease to no more than a specified percentage (the "Payment Cap") of the previous year's minimum payment amount. In addition, the minimum payment is subject to an automatic adjustment every five years or if the outstanding principal balance of the mortgage loan exceeds a specified percentage of the original principal balance, in each case without regard to the Payment Cap limitation. On each annual adjustment date and in the event of an automatic adjustment, the minimum monthly payment is adjusted to an amount sufficient to fully amortize the mortgage loan based on the then-current mortgage interest rate and remaining scheduled term of the loan, unless, in the case of an annual adjustment, the monthly payment is restricted by the Payment Cap limitation, in which case the monthly payment is adjusted by the Payment Cap. A minimum payment may not cover the amount of interest accrued during a month and may not pay down any principal. Any interest not covered by a monthly payment ("Deferred Interest") will be added to the principal balance of the Mortgage Loan. This is called "negative amortization" and results in an increase in the amount of principal the borrower owes. Interest will then accrue on this new larger principal balance. The index for an Option ARM Mortgage Loan will be determined monthly or at other less frequent intervals specified in the applicable prospectus supplement.

c. Interest Only Mortgage Loans. If so specified in the applicable prospectus supplement, a Trust Estate may contain (i) Mortgage Loans having an original term to maturity of not more than 40 years with a Mortgage Interest Rate which adjusts initially either six months, one, three, five, seven or ten years subsequent to the initial payment date, and thereafter at six-month, one-year or other intervals (with corresponding adjustments in the amount of monthly payments) over the term of the mortgage loan to equal the sum of the related gross margin and index, and providing for monthly payments of interest only prior to the date specified in the related Mortgage Note and monthly payments of principal and interest after the date specified in the related Mortgage Note sufficient to fully-amortize the Mortgage Loans over their remaining terms to maturity ("Adjustable Rate Interest Only Mortgage Loans") or (ii) fixed rate, fully-amortizing Mortgage Loans having an original term to maturity of not more than 40 years providing for monthly payments of interest only prior to a date specified in the Mortgage Note and monthly payments of principal and interest after such date sufficient to fully-amortize the Mortgage Loans over their remaining terms to maturity ("Fixed Rate Interest Only Mortgage Loans" and, together with Adjustable Rate Interest Only Mortgage Loans, "Interest Only Mortgage Loans").

d. Graduated Payment Loans. If so specified in the applicable prospectus supplement, a Trust Estate may contain fixed rate, graduated payment Mortgage Loans having original or modified terms to maturity of not more than 40 years with monthly payments during the first year calculated on the basis of an assumed interest rate which is a specified percentage below the Mortgage Rate on such Mortgage Loan. Such monthly payments increase at the

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beginning of the second year by a specified percentage of the monthly payment during the preceding year and each year specified thereafter to the extent necessary to amortize the Mortgage Loan over the remainder of its term or other shorter period. Mortgage Loans incorporating such graduated payment features may include (i) "Graduated Pay Mortgage Loans," pursuant to which amounts constituting Deferred Interest are added to the principal balances of such mortgage loans, (ii) "Tiered Payment Mortgage Loans," pursuant to which, if the amount of interest accrued in any month exceeds the current scheduled payment for such month, such excess amounts are paid from a subsidy account (usually funded by a home builder or family member) established at closing and (iii) "Growing Equity Mortgage Loans," for which the monthly payments increase at a rate which has the effect of amortizing the loan over a period shorter than the stated term.

e. Subsidy Loans. If so specified in the applicable prospectus supplement, a Trust Estate may contain Mortgage Loans subject to temporary interest subsidy agreements ("Subsidy Loans") pursuant to which the monthly payments made by the related mortgagors will be less than the scheduled monthly payments on such Mortgage Loans with the present value of the resulting difference in payment ("Subsidy Payments") being provided by the employer of the mortgagor, generally on an annual or quarterly basis. Subsidy Payments will generally be placed in a custodial account ("Subsidy Account") by the related Servicer. Despite the existence of a subsidy program, a mortgagor remains primarily liable for making all scheduled payments on a Subsidy Loan and for all other obligations provided for in the related Mortgage Note and Mortgage Loan.

The terms of the subsidy agreements relating to Subsidy Loans generally range from one to ten years. Subsidy Loans are offered by employers generally through either a "graduated" or "fixed" subsidy loan program, or programs that combine features of graduated and fixed subsidy loan programs. The subsidy agreements relating to Subsidy Loans made under a graduated program generally will provide for subsidy payments that result in effective subsidized interest rates between three percentage points (3%) and five percentage points (5%) below the Mortgage Interest Rates specified in the related Mortgage Notes during the term of the subsidy agreement. Generally, under a graduated program, the subsidized rate for a Mortgage Loan will increase approximately one percentage point per year until it equals the full Mortgage Interest Rate. For example, if the initial subsidized interest rate is five percentage points below the Mortgage Interest Rate in year one, the subsidized rate will increase to four percentage points below the Mortgage Interest Rate in year two, and likewise until year six, when the subsidized rate will equal the Mortgage Interest Rate. Where the subsidy agreements relating to Subsidy Loans are in effect for longer than five years, the subsidized interest rates generally increase at smaller percentage increments for each year. The subsidy agreements relating to Subsidy Loans made under a fixed program generally will provide for subsidized interest rates at fixed percentages (generally one percentage point to two percentage points) below the Mortgage Interest Rates for the term of the subsidy agreements. The subsidy agreements relating to Subsidy Loans pursuant to combination fixed/graduated programs generally will provide for an initial fixed subsidy of up to five percentage points below the related Mortgage Interest Rate for up to five years, and then a periodic reduction in the subsidy for up to five years, at an equal fixed percentage per year until the subsidized rate equals the Mortgage Interest Rate.

Generally, employers may terminate subsidy programs in the event of (i) the mortgagor's death, retirement, resignation or termination of employment, (ii) the full prepayment of the Subsidy Loan by the mortgagor, (iii) the sale or transfer by the mortgagor of the related Mortgaged Property as a result of which the mortgagee is entitled to accelerate the Subsidy Loan pursuant to the "due-on-sale" clause contained in the Mortgage, or (iv) the commencement of foreclosure proceedings or the acceptance of a deed in lieu of foreclosure. In addition, some subsidy programs provide that if prevailing market rates of interest on mortgage loans similar to a Subsidy Loan are less than the Mortgage Interest Rate of such Subsidy Loan, the employer may request that the mortgagor refinance such Subsidy Loan and may terminate the related subsidy agreement if the mortgagor fails to do so. In the event the mortgagor refinances a Subsidy Loan, the new loan will not be included in the Trust Estate. See "Prepayment and Yield Considerations." In the event a subsidy agreement is terminated, the amount remaining in the Subsidy Account will be returned to the employer, and the mortgagor will be obligated to make the full amount of all remaining scheduled payments, if any. The mortgagor's reduced monthly housing expense as a consequence of payments under a subsidy agreement is used by Wells Fargo Bank in determining certain expense-to-income ratios utilized in underwriting a Subsidy Loan. See "Wells Fargo Bank's Mortgage Loan Programs--Mortgage Loan Underwriting."

f. Buy-Down Loans. If so specified in the applicable prospectus supplement, a Trust Estate may contain Mortgage Loans subject to temporary buy-down plans ("Buy-Down Loans") pursuant to which the monthly

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payments made by the mortgagor during the early years of the Mortgage Loan will be less than the scheduled monthly payments on the Mortgage Loan. The resulting difference in payment will be compensated for from an amount contributed by the seller of the related Mortgaged Property or another source, including the originator of the Mortgage Loan (generally on a present value basis) and placed in a custodial account (the "Buy-Down Fund") by the related Servicer. If the mortgagor on a Buy-Down Loan prepays such Mortgage Loan in its entirety, or defaults on such Mortgage Loan and the Mortgaged Property is sold in liquidation thereof, during the period when the mortgagor is not obligated, on account of the buy-down plan, to pay the full monthly payment otherwise due on such loan, the unpaid principal balance of such Buy-Down Loan will be reduced by the amounts remaining in the Buy-Down Fund with respect to such Buy-Down Loan, and such amounts will be deposited in the Servicer Custodial Account or the Certificate Account, net of any amounts paid with respect to such Buy-Down Loan by any insurer, guarantor or other person pursuant to a credit enhancement arrangement described in the applicable prospectus supplement.

g. Balloon Loans. If so specified in the applicable prospectus supplement, a Trust Estate may contain Mortgage Loans which are amortized over a fixed period not exceeding 40 years but which have shorter terms to maturity ("Balloon Loans") causing the outstanding principal balance of the related Mortgage Loan to be due and payable at the end of a certain specified period (the "Balloon Period"). The borrower of such Balloon Loan will be obligated to pay the entire outstanding principal balance of the Balloon Loan at the end of the related Balloon Period. In the event the related mortgagor refinances a Balloon Loan at maturity, the new loan will not be included in the Trust Estate. See "Prepayment and Yield Considerations."

h. Pledged Asset Mortgage Loans. If so specified in the applicable prospectus supplement, a Trust Estate may contain fixed rate mortgage loans having original terms to stated maturity of not more than 40 years which are either (i) secured by a security interest in additional collateral (normally securities) ("Additional Collateral") owned by the borrower, (ii) supported by a third party guarantee (usually a parent of the borrower) which is in turn secured by a security interest in Additional Collateral (usually securities) owned by such guarantor or (iii) supported by a third party letter of credit ("LOC") (any such loans supported by Additional Collateral, the "Additional Collateral Pledged Asset Mortgage Loans," any such loans supported by LOCs, the "LOC Pledged Asset Mortgage Loans" and together with the Additional Collateral Pledged Asset Mortgage Loans, the "Pledged Asset Mortgage Loans").

With respect to an Additional Collateral Pledged Asset Mortgage Loan, the amount of the Additional Collateral generally does not exceed 30% of the original principal balance of such Additional Collateral Pledged Asset Mortgage Loan. The requirement to maintain Additional Collateral terminates when the principal balance of an Additional Collateral Pledged Asset Mortgage Loan is paid down to a predetermined amount. The pledge agreement and the security interest in such Additional Collateral will be assigned to the Trustee. It is anticipated that, in the event of a loss upon the liquidation of an Additional Collateral Pledged Asset Mortgage Loan, Merrill Lynch Credit Corporation, which will administer the Additional Collateral, will attempt to realize on the related security interest. No assurance can be given as to the amount of proceeds, if any, that might be realized from such Additional Collateral. In no event will the Trust Estate be permitted to acquire ownership of the Additional Collateral. Ambac Assurance Corporation (the "Surety Bond Provider") has previously issued a limited purpose surety bond (the "Limited Purpose Surety Bond"), to cover the Additional Collateral Pledged Asset Mortgage Loans, which is intended to guarantee payment to the Trust Estate of certain shortfalls in the net proceeds realized from the liquidation of any required Additional Collateral (such amount not to exceed 30% of the original principal amount of an Additional Collateral Pledged Asset Mortgage Loan) to the extent any such shortfall results in a loss of principal on an Additional Collateral Pledged Asset Mortgage Loan upon liquidation. The Limited Purpose Surety Bond will not cover any payments on the Certificates of the related Servicer that are recoverable or sought to be recovered as voidable preferences under applicable law. Although the Limited Purpose Surety Bond is limited in amount (the "Maximum Amount"), the Depositor has been advised by the Surety Bond Provider that the Maximum Amount is, and will be, sufficient to cover all potential claims on behalf of the Trust Estate with respect to the Additional Collateral securing an Additional Collateral Pledged Asset Mortgage Loan and on behalf of other assignees of additional collateral securing similar mortgage loans covered by such Limited Purpose Surety Bond.

In connection with each LOC Pledged Asset Mortgage Loan, the borrower pledged securities it owns to UBS Financial Services Inc. as security for an LOC issued by UBS Financial Services Inc. in favor of Wells Fargo Bank, as originator of such Mortgage Loan. The amount of pledged securities which can be drawn under each LOC (the "Pledged Value") is generally equal to at least 20% of the purchase price or appraised value of the Mortgaged

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Property (whichever is less). The Pledged Value may be reduced by the amount of the borrower's equity in the property or any down payment made by such borrower. Pursuant to an agreement between the borrower and Wells Fargo Bank, in the event that the borrower becomes ninety days or more delinquent on an LOC Pledged Asset Mortgage Loan, Wells Fargo Bank will have the right, at its option, to draw on all or a portion of the LOC for an amount up to the LOC's Pledged Value. Wells Fargo Bank, as Servicer, may then, at its discretion, either (i) immediately apply the proceeds from drawing on the LOC as a curtailment or partial prepayment of the unpaid principal balance of the LOC Pledged Asset Mortgage Loan or (ii) apply the proceeds from drawing on the LOC at a later date in accordance with Wells Fargo Bank's default and servicing procedures. With respect to some of the LOC Pledged Asset Mortgage Loans, on the Closing Date, Wells Fargo Bank will assign its right to receive the proceeds of the LOCs to the Depositor, which in turn, will assign such right to the Trust. However, Wells Fargo Bank will remain the beneficiary of the LOCs. Wells Fargo Bank will agree in the Underlying Servicing Agreement to make all draws on the LOCs in accordance with their terms on behalf of the Trust. This obligation will continue even if Wells Fargo Bank is no longer the Servicer of the LOC Pledged Asset Mortgage Loans. With respect to the remaining LOC Pledged Asset Mortgage Loans, on the Closing Date, Wells Fargo Bank will assign the LOCs to the Depositor, which, in turn, will assign the LOCs to the Trust which will become the beneficiary thereunder. For these LOC Pledged Asset Mortgage Loans, Wells Fargo Bank (and any successor Servicer) will agree in the Underlying Servicing Agreement to make claims on the LOCs in accordance with their terms on behalf of the Trust. No assurance can be given as to the amount of proceeds, if any, that might be realized from an LOC related to an LOC Pledged Asset Mortgage Loan. The Trust will not have any interest in the securities which a borrower has pledged to UBS Financial Services Inc. in connection with any LOC Pledged Asset Mortgage Loan.

Mortgage Certificates

The Mortgage Certificates will be acquired by the Depositor from Wells Fargo Bank or one or more affiliated or unaffiliated entities named in the applicable prospectus supplement. The Mortgage Certificates will be backed by residential mortgage loans as described in the applicable prospectus supplement or a prospectus for the Mortgage Certificates delivered simultaneously with the prospectus supplement.

All of the Mortgage Certificates will be registered in the name of the Trustee or its nominee, or the Securities Administrator or its nominee, on behalf of the Trustee or, in the case of Mortgage Certificates issued only in book-entry form, a financial intermediary (which may be the Securities Administrator) that is a member of the Federal Reserve System or of a clearing corporation on the books of which the security is held. Each Mortgage Certificate will evidence an interest in a pool of Mortgage Loans of a type described in the previous section.

The Mortgage Certificates will consist of mortgage asset-backed pass-through certificates previously issued in a transaction for which Wells Fargo Asset Securities Corporation acted as Depositor. The Mortgage Certificates may be of any type described under "Description of the Certificates--Categories of Classes of Certificates" in this prospectus and may be Exchangeable Certificates. The terms of any Mortgage Certificates that are included in a Trust Estate will be described in the related prospectus supplement.

The Sponsor of a Series backed by Mortgage Certificates (other than Wells Fargo Bank) will have acquired the Mortgage Certificates in open market transactions or in privately negotiated transactions which may be through affiliates. The Sponsor may have acted as an underwriter of the Mortgage Certificates and the Mortgage Certificates may constitute part of its unsold allotment.

The prospectus supplement for a Series issued by a Trust containing Mortgage Certificates or a prospectus for the Mortgage Certificates delivered simultaneously with the prospectus supplement will specify to the extent material, among other things, the following:

o the aggregate approximate principal amount and type of the Mortgage Certificates to be included in the Trust Estate;

o certain characteristics of the mortgage loans underlying the Mortgage Certificates (the "Underlying Loans") including:

o the payment features of such Underlying Loans;

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o the servicing fee or range of servicing fees with respect to the Underlying Loans; and

o the minimum and maximum stated maturities of the Underlying Loans at origination;

o the Mortgage Certificate Pass-Through Rates for the Mortgage Certificates;

o the weighted average Mortgage Certificate Pass-Through Rate;

o the underlying sponsor, trustee and servicer of the trust that issued the Mortgage Certificates;

o the credit support for the Mortgage Certificates;

o any cashflow agreements, such as yield maintenance agreements or swap agreements, relating to the Mortgage Certificates; and

o the terms on which the Underlying Loans may, or are required to be, purchased prior to maturity of the Mortgage Certificates.

For any Series of Certificates backed by Mortgage Certificates:

o the prospectus and prospectus supplement relating to the offering of the Mortgage Certificates will be delivered along with, or will be combined with, the prospectus supplement for the offering of the Series of Certificates backed by Mortgage Certificates;

o the related prospectus supplement will describe the plan of distribution for both the Mortgage Certificates and the Series of Certificates backed by Mortgage Certificates, and

o the issuing entity, depositor, sponsor and each underwriter for the offering of the Series of Certificates backed by Mortgage Certificates will be an underwriter for the offering of the Mortgage Certificates.

Cash Flow Agreements

General

If specified in the applicable prospectus supplement, the Trust Estate may include cash flow agreements consisting only of one or more guaranteed investment contracts, swap agreements or interest rate cap or floor agreements (also called yield maintenance agreements), each of which agreements is intended to reduce the effects of interest rate fluctuations on the assets or on one or more Classes of Certificates (each, a "Cash Flow Agreement"). The applicable prospectus supplement will describe the name, organizational form and general character of the business of the counterparty under any Cash Flow Agreement. In addition, the prospectus supplement for the related Series of Certificates will disclose whether the aggregate significance percentage related to any entity or group of affiliated entities providing a Cash Flow Agreement is less than 10%, at least 10% but less than 20%, or 20% or more, calculated in accordance with Item 1115 of Regulation AB (17 C.F.R. 229.1115). To the extent this percentage is (a) 10% or more but less than 20%, the applicable prospectus supplement will provide financial data required by Item 301 of Regulation S-K (17 C.F.R. 229.301) or (b) 20% or more, the related prospectus supplement will provide financial statements required by Item 1115(b)(2) of Regulation AB (17 C.F.R. 229.1115) and, in either case, the applicable prospectus supplement will contain a description of the operation and material terms of the Cash Flow Agreement, including, without limitation, conditions to payment or limits on the timing or amount of payments and material provisions relating to the termination or substitution of the Cash Flow Agreement. Copies of the Cash Flow Agreement, if any, relating to a Series of Certificates will be filed with the SEC as an exhibit to a Current Report on Form 8-K.

Guaranteed Investment Contract

If specified in the applicable prospectus supplement, the Trustee (or other party specified in the applicable prospectus supplement) on behalf of the Trust may enter into one or more guaranteed investment contracts. Guaranteed investment contracts are generally used to maximize the investment income on funds held between

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Distribution Dates pending distribution to Certificateholders. Under a guaranteed investment contract, the issuer of the contract, which is typically a highly rated financial institution, guarantees a fixed or floating rate of interest over the life of the contract, as well as the ultimate return of the principal. Any payments received from the issuer of the contract by the Trust will be distributed to the related Class or Classes of Certificates as specified in the applicable prospectus supplement.

Yield Maintenance Agreements

If specified in the applicable prospectus supplement, the Trustee (or other party specified in the applicable prospectus supplement) on behalf of the Trust will enter into one or more yield maintenance agreements in order to support the yield of one or more Classes of Certificates. The counterparty to a yield maintenance agreement will receive an upfront payment and the Trust will have no ongoing payment obligations. Generally, if one-month LIBOR or another index specified in the applicable prospectus supplement exceeds a percentage for a particular date specified in the applicable prospectus supplement, the counterparty to the yield maintenance agreement will be required to pay to the Trustee (or other party specified in the applicable prospectus supplement) an amount equal to that excess multiplied by a notional amount or the principal balance or balances of one or more Classes of Certificates multiplied by one-twelfth. This amount may be adjusted to reflect the actual number of days in the Interest Accrual Period for the related Class or Classes of Certificates and will be paid to the Class or Classes of Certificates as specified in the applicable prospectus supplement.

Swap Agreements

If specified in the applicable prospectus supplement, the Trustee (or other party specified in the applicable prospectus supplement) on behalf of the Trust will enter into a swap agreement to support the yield on one or more Classes of Certificates. Under the swap agreement, the Trust will be obligated to pay an amount equal to a certain percentage of a notional amount set forth in the applicable prospectus supplement to the counterparty and the Trust will be entitled to receive an amount equal to one-month LIBOR or another interest rate index specified in the applicable prospectus supplement on the notional amount from the counterparty, until the swap agreement is terminated. Only the net amount of the two obligations will be paid by the appropriate party. In the event that the Trust is required to make a payment to the counterparty, that payment will be paid on the related Distribution Date prior to distributions to Certificateholders. Generally, any payments received from the counterparty by the Trust will be distributed to cover certain shortfalls as set forth in the applicable prospectus supplement.

If specified in the applicable prospectus supplement, the Trustee (or other party specified in the applicable prospectus supplement) on behalf of the Trust will enter into one or more interest rate swap agreements to cover any shortfalls on one or more Classes of Certificates in the event those Certificates are auctioned to third-party investors on a date specified in the applicable prospectus supplement and the proceeds from the auction are less than the outstanding principal balance of the applicable Class or Classes of Certificates plus any accrued and unpaid interest. In the event the proceeds from the auction are greater than the outstanding principal balance of the applicable Class or Classes of Certificates plus any accrued and unpaid interest, this excess will be paid to the counterparty or counterparties under the swap agreement(s).

THE SPONSOR

Wells Fargo Bank, N.A. ("Wells Fargo Bank") or another entity named in the prospectus supplement will be the sponsor (the "Sponsor") of each Series of Certificates. Wells Fargo Bank will be the Sponsor for any Series issued by a Trust containing Mortgage Loans. Wells Fargo Bank will also be the Paying Agent for each Series of Certificates and will be the Master Servicer and a Servicer for each Series of Certificates issued by a Trust containing Mortgage Loans and the Securities Administrator for each Series of Certificates issued by a Trust containing Mortgage Certificates. Wells Fargo Bank is an indirect, wholly-owned subsidiary of Wells Fargo & Company. Wells Fargo Bank is a national banking association and is engaged in a wide range of activities typical of a national bank. On February 20, 2004, Wells Fargo Bank Minnesota, National Association was merged into Wells Fargo Bank. Wells Fargo Bank Minnesota, National Association was formerly called Norwest Bank Minnesota, National Association. Norwest Bank Minnesota, National Association changed its name to Wells Fargo Bank Minnesota, National Association on July 8, 2000.

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On May 8, 2004, Wells Fargo Home Mortgage, Inc., a wholly-owned subsidiary of Wells Fargo Bank, was merged into Wells Fargo Bank. Wells Fargo Home Mortgage, Inc. was engaged principally in the business of (i) originating, purchasing and selling residential mortgage loans in its own name and through certain of its affiliates (the "Wells Fargo Affiliates") and (ii) servicing residential mortgage loans for its own account or for the account of others. The origination and servicing activities formerly carried on by Wells Fargo Home Mortgage, Inc. are now performed by the Wells Fargo Home Mortgage division of Wells Fargo Bank. Wells Fargo Bank is an approved servicer of Fannie Mae, Freddie Mac and the Government National Mortgage Association. Wells Fargo Bank's principal office is located in San Francisco, California.

Wells Fargo Bank has sponsored publicly offered securitization transactions since 1996. Wells Fargo Bank and it affiliates have originated residential mortgage loans, commercial mortgage loans, auto loans, home equity loans, credit card receivables and student loans. Wells Fargo Bank and it affiliates have also served as sponsors, issuers, master servicers, servicers and trustees in a wide array of securitization transactions. While Wells Fargo Bank currently does not rely on securitization as a material funding source, the Depositor's securitization programs are a material funding source for Wells Fargo Bank's residential mortgage loan production.

Wells Fargo Bank conducts the securitization of residential mortgage loans originated by it or acquired by it from Correspondents through three securitization programs of the Depositor, which is a wholly-owned subsidiary of Wells Fargo Bank. The Depositor's Wells Fargo Alternative Mortgage Backed Securities ("WFALT") program is used to securitize the following types of residential mortgage loans that were originated or acquired by Wells Fargo Bank:

a. Fixed rate mortgage loans having original terms to maturity of approximately twenty years to approximately forty years, and which mortgage loans were originated pursuant to Wells Fargo Bank's underwriting guidelines for "prime" mortgage loans and in connection with the purchases of residences of relocated employees of various corporate employers that participated in the relocation program of Wells Fargo Bank and of various non-participant employers ("Prime 30-Year Fixed Rate Relocation Loans");

b. Fixed rate mortgage loans having original terms to maturity of approximately twenty years to approximately forty years, and which mortgage loans were originated pursuant to the Wells Fargo Bank's underwriting guidelines for "prime" mortgage loans and which were not originated in connection with any relocation program ("Prime 30-Year Fixed Rate Non-Relocation Loans" and, together with Prime 30-Year Fixed Rate Relocation Loans, "Prime 30-Year Fixed Rate Loans");

c. Fixed rate mortgage loans having original terms to maturity of approximately ten years to approximately fifteen years, and which mortgage loans were originated pursuant to the Wells Fargo Bank's underwriting guidelines for "prime" mortgage loans ("Prime 15-Year Fixed Rate Loans" and, together with Prime 30-Year Fixed Rate Loans, "Prime Fixed Rate Loans");

d. Adjustable rate mortgage loans having original terms to maturity of approximately ten to approximately forty years, and which mortgage loans were originated pursuant to the Wells Fargo Bank's underwriting guidelines for "prime" mortgage loans ("Prime Adjustable Rate Loans" and, together with Prime Fixed Rate Loans, "Prime Loans");

e. Fixed rate mortgage loans having original terms to maturity of approximately ten years to approximately forty years, and which mortgage loans were originated pursuant to Wells Fargo Bank's underwriting guidelines for "Alt-A Prime" mortgage loans ("Alt-A Prime Fixed Rate Loans");

f. Adjustable rate mortgage loans having original terms to maturity of approximately ten years to approximately forty years, and which mortgage loans were originated pursuant to Wells Fargo Bank's underwriting guidelines for "Alt-A Prime" mortgage loans ("Alt-A Prime Adjustable Rate Loans");

g. Fixed rate mortgage loans having original terms to maturity of approximately ten years to approximately forty years, and which mortgage loans were originated pursuant to Wells Fargo Bank's underwriting guidelines for "Alt-A Minus" mortgage loans ("Alt-A Minus Fixed Rate Loans"); and

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h. Adjustable rate mortgage loans having original terms to maturity of approximately ten years to approximately forty years, and which mortgage loans were originated pursuant to Wells Fargo Bank's underwriting guidelines for "Alt-A Minus" mortgage loans ("Alt-A Minus Adjustable Rate Loans").

From and including 1996 and through 2007, Wells Fargo Bank and its affiliates and predecessors originated or acquired a total of $2.733 trillion of residential mortgage loans, which include the types of mortgage loans listed above as well as other types of residential mortgage loans originated or acquired by Wells Fargo Bank and its affiliates and predecessors. The table below sets forth for each of the periods indicated the number and aggregate original principal balance of mortgage loans originated or acquired by Wells Fargo Bank (other than any mortgage loans sold to Fannie Mae, Freddie Mac and Federal Home Loan Banks or mortgage loans insured or guaranteed by the Government National Mortgage Association, Federal Housing Administration or Department of Veterans Affairs) for each of the different "asset types" set forth in the table:

                                                          2005                       2006                        2007
                                                          ----                       ----                        ----
                                                                                          Aggregate
                                                             Aggregate                     Original                   Aggregate
                                                No. of   Original Principal   No. of      Principal       No. of  Original Principal
Asset Type                                       Loans    Balance of Loans    Loans    Balance of Loans   Loans    Balance of Loans
----------------------------------
Prime 30-Year Fixed Rate Relocation Loans         1,662        $834,847,437    1,795       $942,828,963    3,023      $1,859,707,794
Prime 30-Year Fixed Rate Non-Relocation Loans    56,987      27,717,640,372   48,644     22,134,618,223   52,054      28,933,977,082
Prime 15-Year Fixed Rate Loans                    5,664       3,050,313,288    2,507      1,230,499,787    2,215       1,400,838,857
Prime Adjustable Rate Loans*                    133,547      61,563,540,910   71,276     39,675,838,574   35,574      23,233,635,489
Alt-A Prime Fixed Rate Loans                      2,445         556,193,433    5,320      1,209,020,397   12.436       3,715,294,105
Alt-A Prime Adjustable Rate Loans*                    0                   0    1,220        420,962,607    3,786       1,568,299,371
Alt-A Minus Fixed Rate Loans                     24,630       4,499,161,624   23,218      4,343,902,519    2,652         582,694,232
Alt-A Minus Adjustable Rate Loans                 8,143       1,772,154,001    1,413        293,559,837      362          97,798,467


* All of the mortgage loans previously reported under "Alt-A Prime Adjustable Rate Loans" for 2005 were "prime" investment property mortgage loans. In 2006, Wells Fargo Bank changed the classification of "prime" adjustable rate investment property mortgage loans so that such mortgage loans are classified as Prime Adjustable Rate Loans and are now reported under that "asset type" for all periods shown.

Only Certificates backed by, or Certificates backed by Mortgage Certificates backed by, Prime 30-Year Fixed Rate Relocation Loans, Prime 30-Year Fixed Rate Non-Relocation Loans, Prime 15-Year Fixed Rate Loans, Prime Adjustable Rate Loans, Alt-A Prime Fixed Rate Loans, Alt-A Prime Adjustable Rate Loans, Alt-A Minus Fixed Rate Loans and/or Alt-A Minus Adjustable Rate Loans are securitized under the Depositor's WFALT securitization program and will be offered pursuant to this prospectus. The aggregate initial unpaid principal balance of residential mortgage asset-backed securities issued under the Depositor's WFALT securitization programs and those of its predecessors from and including 1996 through 2007 is $8.236 billion.

The following table shows the aggregate initial principal balances of residential mortgage asset-backed securities relating to each of the different "asset types" set forth in the table which have been offered under the Depositor's WFALT securitization program during each of the years indicated and the total number of issuances of residential mortgage asset-backed securities which have been offered under the Depositor's WFALT securitization program for each of the years indicated:

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                                                     2005                2006                2007
                                              -----------------   -----------------   -----------------
Asset                                         Aggregate Initial   Aggregate Initial   Aggregate Initial
Type                                          Principal Balance   Principal Balance   Principal Balance
-----------------------------------------     -----------------   -----------------   -----------------
Prime 30-Year Fixed Rate Relocation Loans             *                   *                   *
Prime 30-Year Fixed Rate                              *                   *                   *
Non-Relocation Loans
Prime 15-Year Fixed Rate Loans                        *                   *                   *
Prime Adjustable Rate Loans                           *                   *                   *
Alt-A Prime Fixed Rate Loans                    $217,289,883              *              $3,891,787,108
Alt-A Prime Adjustable Rate Loans*                    *                   *              $1,236,495,036
Alt-A Minus Fixed Rate Loans                    $344,994,234              *                   *
Alt-A Minus Adjustable Rate Loans                     *                   *                   *
                                                     2005                2006                2007
                                              -----------------   -----------------   -----------------
Total Number of Issuances                             2                   0                   6


* There were no Mortgage Loans of this "asset type" offered under the Depositor's WFALT securitization program for the years indicated.

The Mortgage Loans included in the Depositor's residential mortgage asset-backed securitization programs are either originated by Wells Fargo Bank or purchased by Wells Fargo Bank or an affiliate of Wells Fargo Bank from various entities that originated the Mortgage Loans to Wells Fargo Bank's general or alternative underwriting standards or other underwriting standards which will be described in the prospectus supplement. See "The Trust Estates-Mortgage Loans" in this prospectus. Wells Fargo Bank sells the mortgage loans to the Depositor by means of a mortgage loan purchase agreement between Wells Fargo Bank and the Depositor. Wells Fargo Bank acts as servicer of some or all of the mortgage loans included in its securitization program and also acts as master servicer for each trust containing Mortgage Loans, supervising the servicers and performing certain other administrative and reporting duties with respect to each series of certificates relating to each such trust. Wells Fargo Bank acts as securities administrator for each trust containing Mortgage Certificates, performing securities administration services and certain other administrative and reporting duties with respect to each series of certificates relating to each such trust.

See "Wells Fargo Bank's Mortgage Loan Programs," "Servicing of the Mortgage Loans," "The Pooling and Servicing Agreement" and "The Trust Agreement" for more information about Wells Fargo Bank, its securitization programs and underwriting criteria used to originate the Mortgage Loans and its material roles and duties in each securitization.

WELLS FARGO BANK'S MORTGAGE LOAN PROGRAMS

Mortgage Loan Production Sources

Wells Fargo Bank originates and acquires mortgage loans through a network of retail, wholesale and correspondent offices located throughout many states in the United States, the District of Columbia and several of the territories of the United States. Wells Fargo Bank also receives applications for home mortgage loans on toll-free telephone numbers that can be called from anywhere in the United States. Wells Fargo Bank also provides information and accepts applications through the internet.

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The following are Wells Fargo Bank's primary sources of mortgage loan originations: (i) direct contact with prospective borrowers (including borrowers with mortgage loans currently serviced by Wells Fargo Bank or borrowers referred by borrowers with mortgage loans currently serviced by Wells Fargo Bank), (ii) referrals from realtors, other real estate professionals and prospective borrowers, (iii) referrals from selected corporate clients, (iv) referrals from or originations by Wells Fargo Bank's Private Mortgage Banking division and other affiliated banks, which specializes in providing services to individuals meeting certain earnings, liquidity or net worth parameters, (v) referrals from or originations by several joint ventures into which Wells Fargo Bank, through its wholly owned subsidiary, Wells Fargo Ventures, LLC, has entered with realtors and banking institutions (the "Joint Ventures") and (vi) referrals from mortgage brokers and similar entities. In addition to its own mortgage loan originations, Wells Fargo Bank acquires qualifying mortgage loans from other unaffiliated originators ("Correspondents"). See "--Acquisition of Mortgage Loans from Correspondents" below. The relative contribution of each of these sources to Wells Fargo Bank's origination business, measured by the volume of loans generated, tends to fluctuate over time.

Wells Fargo Ventures, LLC owns at least a 50% interest in each of the Joint Ventures, with the remaining ownership interest in each being owned by a realtor or a banking institution having significant contact with potential borrowers. Mortgage loans that are originated by Joint Ventures in which Wells Fargo Bank's partners are realtors are generally made to finance the acquisition of properties marketed by such Joint Venture partners. Applications for mortgage loans originated through Joint Ventures are generally taken by Joint Venture employees and underwritten by Wells Fargo Bank in accordance with its standard underwriting criteria. Such mortgage loans are then closed by the Joint Ventures in their own names and subsequently purchased by Wells Fargo Bank or the Wells Fargo Affiliates.

Wells Fargo Bank may directly contact prospective borrowers (including borrowers with mortgage loans currently serviced by Wells Fargo Bank) through general and targeted solicitations. Such solicitations are made through direct mailings, mortgage loan statement inserts and television, radio and print advertisements and by telephone. Wells Fargo Bank's targeted solicitations may be based on characteristics such as the borrower's mortgage loan interest rate or payment history and the geographic location of the mortgaged property. See "Prepayment and Yield Considerations."

Many of Wells Fargo Bank's corporate clients are companies that sponsor relocation programs for their employees and in connection with which Wells Fargo Bank provides mortgage financing. Eligibility for a relocation loan is based, in general, on an employer's providing financial assistance to the relocating employee in connection with a job-required move. Although Subsidy Loans are typically generated through such corporate-sponsored programs, the assistance extended by the employer need not necessarily take the form of a loan subsidy. Not all relocation loans are generated by Wells Fargo Bank through referrals from its corporate clients; some relocation loans are generated as a result of referrals from mortgage brokers and similar entities and others are generated through Wells Fargo Bank's acquisition of mortgage loans from other originators. Also among Wells Fargo Bank's corporate clients are various professional associations. These associations, as well as the other corporate clients, promote the availability of a broad range of Wells Fargo Bank mortgage products to their members or employees, including refinance loans, second-home loans and investment-property loans.

Acquisition of Mortgage Loans from Correspondents

In order to qualify for participation in Wells Fargo Bank's mortgage loan purchase programs, lending institutions must (i) meet and maintain certain net worth and other financial standards, (ii) demonstrate experience in originating residential mortgage loans, (iii) meet and maintain certain operational standards, (iv) evaluate each loan offered to Wells Fargo Bank for consistency with Wells Fargo Bank's underwriting guidelines or the standards of a pool insurer and represent that each loan was underwritten in accordance with Wells Fargo Bank standards or the standards of a pool insurer and (v) utilize the services of qualified appraisers.

The contractual arrangements with Correspondents may involve the commitment by Wells Fargo Bank to accept delivery of a certain dollar amount of mortgage loans over a period of time. This commitment may be satisfied either by delivery of mortgage loans one at a time or in multiples as aggregated by the Correspondent. With respect to Alt-A Minus Mortgage Loans, the contractual arrangements with Correspondents may also involve the delegation of all underwriting functions to such Correspondents ("Delegated Underwriting"), which will result

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in Wells Fargo Bank not performing any underwriting functions prior to acquisition of the loan but instead relying on such Correspondents' representations and, in the case of bulk purchase acquisitions from such Correspondents, Wells Fargo Bank's post-purchase reviews of samplings of mortgage loans acquired from such Correspondents regarding the Correspondents' compliance with Wells Fargo Bank's underwriting standards. In all instances, however, acceptance by Wells Fargo Bank is contingent upon the loans being found to satisfy Wells Fargo Bank's program standards or the standards of a pool insurer. Wells Fargo Bank may also acquire mortgage loans in negotiated transactions under which the mortgage loans may have been originated by the seller or another third party according to underwriting standards that may have varied materially from Wells Fargo Bank's general or alternative underwriting standards. To the extent that 20% or more of the aggregate principal balance of the Mortgage Loans in a Trust Estate are underwritten by a Correspondent whose underwriting standards vary materially from Wells Fargo Bank's general or alternative underwriting standards, the applicable prospectus supplement will describe such underwriting standards for such Mortgage Loans.

Mortgage Loan Underwriting

The Trust for each Series of Certificates will include Mortgage Loans, or Mortgage Certificates backed by Mortgage Loans, which have been underwritten in accordance with one or more of the following: (i) Wells Fargo Bank's "general" underwriting standards, (ii) Wells Fargo Bank's "retention program," (iii) Wells Fargo Bank's modified underwriting standards that have been applied in the underwriting of mortgage loans under Wells Fargo Bank's "alternative" mortgage loan underwriting program, (iv) the underwriting standards of a pool insurer and
(v) the underwriting standards of participants in Wells Fargo Bank's non-agency conduit program.

General

The underwriting functions of Wells Fargo Bank are performed in offices throughout many states in the United States, the District of Columbia, and several of the territories of the United States. Wells Fargo Bank may not elect to delegate underwriting authority to any broker or correspondent. Wells Fargo Bank employs loan credit underwriters to scrutinize the applicant's credit profile and to evaluate whether an impaired credit history is a result of adverse circumstances or a continuing inability or unwillingness to meet credit obligations in a timely manner. Personal circumstances such as divorce, family illnesses or deaths and temporary job loss due to layoffs and corporate downsizing will often impair the credit record of certain borrowers.

Wells Fargo Bank's underwriting standards are applied by or on behalf of Wells Fargo Bank to evaluate the applicant's credit standing and ability to repay the loan, as well as the value and adequacy of the mortgaged property as collateral. A prospective borrower applying for a mortgage loan is required to complete a detailed application. The loan application elicits pertinent information about the applicant, with particular emphasis on the applicant's financial health (assets, liabilities, income and expenses), the property being financed and the type of loan desired. A self-employed applicant may be required to submit his or her most recent signed federal income tax returns. With -respect to every applicant, credit reports are obtained from commercial reporting services, summarizing the applicant's credit history with merchants and lenders. Generally, significant unfavorable credit information reported by the applicant or a credit reporting agency must be explained by the applicant. The credit review process generally is streamlined for borrowers with a qualifying Mortgage Score.

The underwriting standards that guide the determination represent a balancing of several factors that may affect the ultimate recovery of the loan amount, including, among others, the amount of the loan, the ratio of the loan amount to the property value (i.e., the lower of the appraised value of the mortgaged property and the purchase price), the borrower's means of support and the borrower's credit history. Wells Fargo Bank's guidelines for underwriting may vary according to the nature of the borrower or the type of loan, since differing characteristics may be perceived as presenting different levels of risk. With respect to certain Mortgage Loans, the originators of such loans may have contracted with unaffiliated third parties to perform the underwriting process. Except as described below, the Mortgage Loans will be underwritten by or on behalf of Wells Fargo Bank generally in accordance with the standards and procedures described herein.

Wells Fargo Bank may supplement the mortgage loan underwriting process with either its own proprietary scoring system or scoring systems developed by third parties such as Freddie Mac's Loan Prospector, Fannie Mae's Desktop Underwriter or scoring systems developed by private mortgage insurance companies. These scoring

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systems assist Wells Fargo Bank in the mortgage loan approval process by providing consistent, objective measures of borrower credit and certain loan attributes. For "prime" borrowers, such objective measures are then used to evaluate loan applications and assign each application a "Mortgage Score."

The portion of the Mortgage Score related to borrower credit history is generally based on computer models developed by a third party. These models evaluate information available from three major credit reporting bureaus regarding historical patterns of consumer credit behavior in relation to default experience for similar types of borrower profiles. A particular borrower's credit patterns are then considered in order to derive a "FICO Score" which indicates a level of default probability over a two-year period.

The Mortgage Score is used to determine the type of underwriting process and which level of underwriter will review the loan file. For transactions which are determined to be low-risk transactions, based upon the Mortgage Score and other parameters (including the mortgage loan production source), the lowest underwriting authority is generally required. For moderate and higher risk transactions, higher level underwriters and a full review of the mortgage file are generally required. Borrowers who have a satisfactory Mortgage Score (based upon the mortgage loan production source) are generally subject to streamlined credit review (which relies on the scoring process for various elements of the underwriting assessments). Such borrowers may also be eligible for a reduced documentation program and are generally permitted a greater latitude in the application of borrower debt-to-income ratios.

With respect to all mortgage loans underwritten by Wells Fargo Bank, Wells Fargo Bank's underwriting of a mortgage loan may be based on data obtained by parties other than Wells Fargo Bank that are involved at various stages in the mortgage origination or acquisition process. This typically occurs under circumstances in which loans are subject to an alternative approval process, as when Correspondents, certain mortgage brokers or similar entities that have been approved by Wells Fargo Bank to process loans on its behalf, or independent contractors hired by Wells Fargo Bank to perform underwriting services on its behalf ("contract underwriters") make initial determinations as to the consistency of loans with Wells Fargo Bank underwriting guidelines. Wells Fargo Bank may also permit these third parties to utilize scoring systems in connection with their underwriting process. The underwriting of mortgage loans acquired by Wells Fargo Bank pursuant to a Delegated Underwriting arrangement with a Correspondent may not be reviewed prior to acquisition of the mortgage loan by Wells Fargo Bank although the mortgage loan file is reviewed by Wells Fargo Bank to confirm that certain documents are included in the file. In addition, in order to be eligible to sell mortgage loans to Wells Fargo Bank pursuant to a Delegated Underwriting arrangement, the originator must meet certain requirements including, among other things, certain quality, operational and financial guidelines. See "--Acquisition of Mortgage Loans from Correspondents" above.

Verifications of employment, income, assets or mortgages may be used to supplement the loan application and the credit report in reaching a determination as to the applicant's ability to meet his or her monthly obligations on the proposed mortgage loan, as well as his or her other mortgage payments (if any), living expenses and financial obligations. A mortgage verification involves obtaining information regarding the borrower's payment history with respect to any existing mortgage the applicant may have. This verification is accomplished by either having the present lender complete a verification of mortgage form, evaluating the information on the credit report concerning the applicant's payment history for the existing mortgage, communicating, either verbally or in writing, with the applicant's present lender or analyzing cancelled checks provided by the applicant. Verifications of income, assets or mortgages may be waived under certain programs offered by Wells Fargo Bank, but Wells Fargo Bank's underwriting guidelines require, in most instances, a verbal or written verification of employment to be obtained. In some cases, employment histories may be obtained through one of various employment verification sources, including the borrower's employer, employer sponsored web sites or third party services specializing in employment verifications. In addition, the loan applicant may be eligible for a loan approval process permitting reduced documentation. The above referenced reduced documentation options and waivers limit the amount of documentation required for an underwriting decision and have the effect of increasing the relative importance of the credit report and the appraisal. Documentation requirements vary based upon a number of factors, including the purpose of the loan, the amount of the loan, the ratio of the loan amount to the property value and the mortgage loan production source. Wells Fargo Bank accepts alternative methods of verification, in those instances where verifications are part of the underwriting decision; for example, salaried income may be substantiated either by means of a form independently prepared and signed by the applicant's employer or by means of the applicant's most recent paystub and/or W-2 (or, in the case of a self-employed applicant, one or more years of the applicant's tax

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return). Loans underwritten using alternative verification methods are considered by Wells Fargo Bank to have been underwritten with "full documentation." In cases where two or more persons have jointly applied for a mortgage loan, the gross incomes and expenses of all of the applicants, including nonoccupant co-mortgagors, are combined and considered as a unit.

In general, borrowers applying for loans must demonstrate that their Debt-to-Income Ratio does not exceed a certain maximum level. Such maximum level varies depending on a number of factors including Loan-to-Value Ratio, a borrower's credit history, a borrower's liquid net worth, the potential of a borrower for continued employment advancement or income growth, the ability of the borrower to accumulate assets or to devote a greater portion of income to basic needs such as housing expense, a borrower's Mortgage Score and the type of loan for which the borrower is applying. These calculations are based on the amortization schedule and the interest rate of the related loan, with the ratio being computed on the basis of the proposed monthly mortgage payment. Generally, the rate used to qualify a borrower for an adjustable-rate mortgage loan with an initial fixed rate period of more than one year is the note rate; provided that if the adjustable-rate mortgage loan has an initial fixed period of three years, an interest only term of three years and a Debt-to-Income Ratio of greater than 36% then the borrower must be qualified using the note rate plus 2%. Generally, the rate used to qualify a borrower for a adjustable-rate mortgage loan with an initial fixed rate period of one year or less is (a) the note rate for a mortgage loan with a Loan-to-Value Ratio of less than or equal to 80% and (b) the note rate plus 2% for mortgage loans with a Loan-to-Value Ratio greater than 80%. In evaluating applications for Subsidy Loans and Buy-Down Loans, the ratio is determined by including in the applicant's total monthly debt the proposed monthly mortgage payment reduced by the amount expected to be applied on a monthly basis under the related subsidy agreement or buy-down agreement or, in certain cases, the mortgage payment that would result from an interest rate lower than the Mortgage Interest Rate but higher than the effective rate to the mortgagor as a result of the subsidy agreement or the buy-down agreement. In the case of interest only mortgage loans, no principal payment is considered in determining the mortgagor's total debt for purposes of such ratio, however, under certain circumstances the interest rate used may be higher than the actual interest rate on the mortgage loan. See "The Trust Estates--Mortgage Loans." In the case of the mortgage loans of certain applicants referred by Wells Fargo Bank's Private Mortgage Banking division, qualifying income may be based on an "asset dissipation" approach under which future income is projected from the assumed liquidation of a portion of the applicant's specified assets. In evaluating an application with respect to a "non-owner-occupied" property, which Wells Fargo Bank defines as a property leased to a third party by its owner (as distinct from a "second home," which Wells Fargo Bank defines as an owner-occupied, non-rental property that is not the owner's principal residence), Wells Fargo Bank will include projected rental income net of certain mortgagor obligations and other assumed expenses or loss from such property to be included in the applicant's monthly gross income or total monthly debt in calculating the foregoing ratio. A mortgage loan secured by a two- to four-family Mortgaged Property is considered to be an owner-occupied property if the borrower occupies one of the units; rental income on the other units is generally taken into account in evaluating the borrower's ability to repay the mortgage loan.

Secondary financing may be provided by Wells Fargo Bank, any of its affiliates or other lenders simultaneously with the origination of the first lien mortgage loan. Wells Fargo Bank or one of its affiliates may provide such secondary financing in the form of a flexible home equity line of credit, the available balance under which may increase on a quarterly basis by one dollar for each dollar applied in payment of the principal balance of the first lien mortgage loan during the preceding quarter (any such loan, a "Home Asset ManagementSM Account Loan"). In addition, the available balance of such line of credit may be eligible for increase on an annual basis by one dollar for each dollar, if any, by which the value of the related Mortgaged Property has increased over the prior year, as determined pursuant to a statistically derived home price index. The payment obligations under both primary and secondary financing are included in the computation of the Debt-to-Income Ratio, and the combined amount of primary and secondary loans will be used to calculate the Combined Loan-to-Value Ratio. Wells Fargo Bank does not restrict a borrower from obtaining secondary financing after origination of the first lien mortgage loan.

Mortgage Loans will generally not have had at origination a Loan-to-Value Ratio in excess of 95%; provided that, for Mortgage Loans originated on or after December 17, 2007, there are certain additional requirements if the Loan-to-Value Ratio exceeds 90%. However, if so specified in the applicable prospectus supplement, Mortgage Loans that had Loan-to-Value Ratios at origination in excess of 95% may be included in the related Trust Estate. The "Loan-to-Value Ratio" or "LTV" is the ratio, expressed as a percentage, of the principal amount of the Mortgage Loan at origination to the lesser of (i) the appraised value of the related Mortgaged Property, as established by an appraisal obtained by the originator generally no more than four months prior to origination

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(subject to the exceptions set forth in the following sentence), or (ii) the sale price for such property. An appraisal for (i) a construction to permanent mortgage loan can be obtained up to 18 months prior to origination; provided that if the property is a manufactured home, the appraisal must be obtained no more than six months prior to origination, (ii) a newly constructed property can be obtained up to 12 months prior to origination if an appraisal update is obtained within six months of origination; provided that if the property is located in an area with declining property values, the appraisal must be obtained no more than four months prior to origination and (iii) an existing property can be obtained up to 12 months prior to origination if an appraisal update is obtained within four months of origination. For the purpose of calculating the Loan-to-Value Ratio of any Mortgage Loan that is the result of the refinancing (including a refinancing for "equity take out" purposes) of an existing mortgage loan, the appraised value of the related Mortgaged Property is generally determined by reference to an appraisal obtained in connection with the origination of the replacement loan. In connection with certain of its mortgage originations, Wells Fargo Bank currently obtains appraisals through Valuation Information Technology, LLC (doing business as RELS Valuation)("RELS"), an entity jointly owned by an affiliate of Wells Fargo Bank and an unaffiliated third party. The "Combined Loan-to-Value Ratio" or "CLTV" is the ratio, expressed as a percentage, of (i) the principal amount of the Mortgage Loan at origination plus (a) any junior mortgage encumbering the related Mortgaged Property originated by the Sponsor or of which the Sponsor has knowledge at the time of the origination of the Mortgage Loan or (b) the total available amount of any home equity line of credit originated by the Sponsor or of which the Sponsor has knowledge at the time of the origination of the Mortgage Loan, over (ii) the lesser of (a) the appraised value of the related Mortgaged Property at origination or (b) the sales price for such property.

No assurance can be given that values of the Mortgaged Properties have remained or will remain at the levels which existed on the dates of appraisal (or, where applicable, on the dates of appraisal updates) of the related Mortgage Loans. The appraisal of any Mortgaged Property reflects the individual appraiser's judgment as to value, based on the market values of comparable homes sold within the recent past in comparable nearby locations and on the estimated replacement cost. The appraisal relates both to the land and to the structure; in fact, a significant portion of the appraised value of a Mortgaged Property may be attributable to the value of the land rather than to the residence. Because of the unique locations and special features of certain Mortgaged Properties, identifying comparable properties in nearby locations may be difficult. The appraised values of such Mortgaged Properties will be based to a greater extent on adjustments made by the appraisers to the appraised values of reasonably similar properties rather than on objectively verifiable sales data. As a result of the implementation of guideline changes by Wells Fargo Bank recently, if a Mortgaged Property is located in an area that Wells Fargo Bank determines has been impacted by significant property value declines, then the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted may be subject to a 5% decrease. If residential real estate values generally or in particular geographic areas decline such that the outstanding balances of the Mortgage Loans and any secondary financing on the Mortgaged Properties in a particular Trust Estate become equal to or greater than the values of the related Mortgaged Properties, the actual rates of delinquencies, foreclosures and losses could be higher than those now generally experienced in the mortgage lending industry and those now experienced in Wells Fargo Bank's servicing portfolios. In addition, adverse economic conditions generally, in particular geographic areas or industries, or affecting particular segments of the borrowing community (such as mortgagors relying on commission income and self-employed mortgagors) and other factors which may or may not affect real property values, including the purposes for which the Mortgage Loans were made and the uses of the Mortgaged Properties, may affect the timely payment by mortgagors of scheduled payments of principal and interest on the Mortgage Loans and, accordingly, the actual rates of delinquencies, foreclosures and losses with respect to any related Trust Estate. See "Prepayment and Yield Considerations--Weighted Average Life of Certificates." To the extent that such losses are not covered by the methods of credit support or the insurance policies described herein, they will be borne by holders of the Certificates of the Series evidencing interests in such Trust Estate.

Wells Fargo Bank originates mortgage loans pursuant to its general underwriting guidelines with Loan-to-Value Ratios in excess of 80% either with or without the requirement to obtain primary mortgage insurance. In cases for which such primary mortgage insurance is obtained, the percentage of the unpaid principal balances of the mortgage loan as set forth in the following table (the "Prime Coverage Percentage") will be covered by primary mortgage insurance (subject to certain standard policy exclusions for default arising from, among other things, fraud or negligence in the origination or servicing of a Mortgage Loan, including misrepresentation by the mortgagor or other persons involved in the origination thereof) from an approved primary mortgage insurance company, typically until the unpaid principal balance of the Mortgage Loan is reduced to an amount that will result in a Loan-to-Value Ratio less than or equal to 80%.

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The Prime Coverage Percentages generally required by Wells Fargo Bank at various levels of Loan-to-Value Ratios are as follows:

                        Prime Coverage Percentages

  Loan-to-Value        Category I Prime Mortgage         Category II Prime
     Ratios                      Loans                    Mortgage Loans
95.01% to 97.00%                  30%                           25%
90.01% to 95.00%                  30%                           25%
85.01% to 90.00%                  25%                           12%
80.01% to 85.00%                  12%                            6%

"Category I Prime Mortgage Loans" includes fixed rate Mortgage Loans with terms to maturity of 25 or 30 years, Balloon Loans amortized over 30 years but with 5 or 7 year terms to maturity and adjustable rate Mortgage Loans with terms to maturity of 30 years and fixed interest rate periods of 5, 7 or 10 years from origination.

"Category II Prime Mortgage Loans" includes fixed rate Mortgage Loans with terms to maturity of 10, 15 or 20 years.

In cases for which such primary mortgage insurance is not obtained, loans having Loan-to-Value Ratios exceeding 80% are required to be secured by primary residences or second homes (excluding Cooperatives). Generally, each loan originated without primary mortgage insurance will have been made at an interest rate that was higher than the rate would have been had the Loan-to-Value Ratios been 80% or less or had primary mortgage insurance been obtained. The prospectus supplement will specify the number and percentage of Mortgage Loans contained in the Trust Estate for a particular Series of Certificates with Loan-to-Value Ratios at origination in excess of 80% which are not covered by primary mortgage insurance.

Except as described below, Mortgage Loans will generally be covered by an appropriate standard form American Land Title Association ("ALTA") title insurance policy, or a substantially similar policy or form of insurance acceptable to Fannie Mae or Freddie Mac. The Depositor will represent and warrant to the Trustee of any Trust Estate containing Mortgage Loans that the Mortgaged Property related to each Mortgage Loan is free and clear of all encumbrances and liens having priority over the first lien of the related Mortgage, subject to certain limited exceptions as set forth below under "The Pooling and Servicing Agreement--Representations and Warranties."

Retention Program

A borrower with at least one mortgage loan serviced by Wells Fargo Bank may be eligible for Wells Fargo Bank's retention program. Provided such a borrower is current in his or her mortgage payment obligations, Wells Fargo Bank may permit a refinancing of one or more of the borrower's mortgage loans that are serviced by Wells Fargo Bank or another servicer to a current market interest rate without applying any significant borrower credit or property underwriting standards. As a result, borrowers who qualify under the retention program may not need to demonstrate that their current Debt-to-Income Ratio does not exceed a certain percentage; Wells Fargo Bank may not obtain a current credit report for the borrower or apply a new FICO Score to the refinanced loan; and the borrower may not be required to provide any verifications of current employment, income level or extent of assets. In addition, no current appraisal or indication of market value may be required with respect to the properties securing the mortgage loans which are refinanced under the retention program. A borrower may participate in this retention program through a refinancing of one or more of his or her existing mortgage loans by either replacing any such loan with a new mortgage loan at a current market interest rate or, in the case of a mortgage loan that had been originated or purchased by Wells Fargo Bank, by executing a modification agreement under which the interest rate on the existing mortgage loan is reduced to a current market rate. Mortgage Loans initially included in the Trust Estate for a particular Series of Certificates may have been the subject of a refinancing under the retention program and, to the extent that borrowers become eligible for the retention program after their Mortgage Loans have been included in a particular Trust Estate, such Mortgage Loans may be refinanced under such program. See "Prepayment and Yield Considerations" in this prospectus and in the prospectus supplement for a description of the potential effects on Certificateholders resulting from such refinancings.

Wells Fargo Bank may also apply the retention program to its existing borrowers who obtain new purchase money mortgage loans secured by primary residences where the initial principal balance of the new loan would not

-41-

exceed 150% of the original principal balance of the previous loan. Borrowers may be pre-approved under this program if they have a satisfactory payment history with Wells Fargo Bank as well as a satisfactory FICO Score. Wells Fargo Bank may waive verifications of borrower income and assets under this program and may not impose any limitation on the ratio of a borrower's current total debt obligation in relation to current monthly income. A new appraisal will be obtained with respect to the residence securing the new purchase money mortgage loan.

Non-Agency Conduit Program

If so specified in the related prospectus supplement, a Trust Estate may contain Mortgage Loans acquired by Wells Fargo Bank under its non-agency conduit program. Under the non-agency conduit program, Wells Fargo Bank acquires mortgage loans from third parties who originate such mortgage loans in accordance with their guidelines, which generally conform to Wells Fargo Bank guidelines. However, there may be some significant differences from Wells Fargo Bank's guidelines and any differences will be described in the related prospectus supplement.

Role of Loan Underwriter Discretion

On a case-by-case basis, a Wells Fargo Bank loan underwriter may make the determination that the prospective borrower warrants loan parameters beyond the general underwriting criteria described above or the specific criteria applicable to Alt-A Mortgage Loans described below based upon the presence of acceptable compensating factors. Examples of compensating factors include, but are not limited to, Loan-to-Value Ratio, Debt-to-Income Ratio, long-term stability of employment and/or residence, credit scores, verified cash reserves or reduction in overall monthly expenses. For example, Wells Fargo Bank permits Debt-to-Income Ratios to exceed guidelines when the applicant has documented compensating factors for exceeding ratio guidelines such as documented excess funds in reserves after closing, a history of making a similar sized monthly debt payment on a timely basis, substantial residual income after monthly obligations are met, evidence that ratios will be reduced shortly after closing when a financed property under contract for sale is sold, or additional income has been verified for one or more applicants that is ineligible for consideration as qualifying income.

Alt-A Mortgage Loans

The underwriting standards applicable to mortgage loans under Wells Fargo Bank's "alternative" mortgage loan underwriting program permit different underwriting criteria as compared to Wells Fargo Bank's general underwriting criteria, additional types of mortgaged properties or categories of borrowers such as "foreign nationals" without a FICO Score who hold certain types of visas and have acceptable credit references (such Mortgage Loans, "Foreign National Loans"), and include certain other less restrictive parameters. Generally, relative to the "general" underwriting standards, these standards include higher loan amounts, higher maximum Loan-to-Value Ratios, higher maximum Combined Loan-to-Value Ratios (in each case, relative to Mortgage Loans with otherwise similar characteristics) in cases of simultaneous primary and secondary financings, less restrictive requirements for "equity take out" refinancing, the removal of limitations on the number of permissible mortgage loans that may be extended to one borrower financing a primary residence and the ability to originate mortgage loans with Loan-to-Value Ratios in excess of 80% without the requirement to obtain primary mortgage insurance.

On July 10, 2006, Wells Fargo Bank implemented new expanded financing solutions for underwriting their "alternative" mortgage loans (the "EFA Program"). Under the EFA Program, mortgage loans are divided into two general categories, "Alt-A Prime" and "Alt-A Minus" and such mortgage loans, "Alt-A Prime Mortgage Loans" and "Alt-A Minus Mortgage Loans." Borrower and mortgage loan characteristics will determine whether a mortgage loan falls within the Alt-A Prime or Alt-A Minus category. The differences between these categories are discussed herein. All "alternative" mortgage loans originated by Wells Fargo Bank on and after July 10, 2006 were originated under the EFA Program guidelines. Unless otherwise specified, the descriptions contained herein are applicable to loans originated before and after the implementation of the EFA Program.

For mortgage loans originated under the EFA Program, if the property is a second home or investment property, the borrower is not permitted to finance more than six one-to-four family residences (including the borrowers primary residence) with Wells Fargo Bank. If the property is a primary residence, there is no limitation on the number of one-to-four family residences that a borrower may finance with Wells Fargo Bank.

-42-

Alt-A Mortgage Loans will generally not have had at origination a Loan-to-Value in excess of 100%. Generally, Wells Fargo Bank originates Alt-A Prime Loans with Loan-to-Value Ratios in excess of 80% with the requirement to obtain primary mortgage insurance and Alt-A Minus Mortgage Loans with Loan-to-Value Ratios in excess of 80% either with or without the requirement to obtain primary mortgage insurance. Generally, for Alt-A Prime Loans the primary insurance is paid by the borrower and for Alt-A Minus Mortgage Loans the primary mortgage insurance is paid by Wells Fargo Bank. In cases where primary mortgage insurance is obtained, the percentage of the unpaid principal balances of the mortgage loans as set forth in the following table (the "Alt-A Coverage Percentage") will be covered by primary mortgage insurance (subject to certain standard policy exclusions for default arising from, among other things, fraud or negligence in the origination or servicing of a Mortgage Loan, including misrepresentation by the mortgagor or other persons involved in the origination thereof) from an approved primary mortgage insurance company, typically until the unpaid principal balance of the Mortgage Loan is reduced to an amount that will result in a Loan-to-Value Ratio less than or equal to 80%.

The Alt-A Coverage Percentages generally required by Wells Fargo Bank for Alt-A Mortgage Loans at various levels of Loan-to-Value Ratios and documentation types are as follows:

Alt-A Coverage Percentages

                                                  Category I Alt-A    Category II Alt-A
Loan-to-Value Ratios     Documentation Types       Mortgage Loans      Mortgage Loans
97.01% to 100.00%         Full documentation            35%           35% for Alt-A Minus
                                                                      30% for Alt-A Prime
95.01% to 97.00%          Full documentation            30%                  25%
90.01% to 95.00%       All documentation levels         30%                  25%
85.01% to 90.00%       All documentation levels         25%                  12%
80.01% to 85.00%       All documentation levels         12%                   6%

"Category I Alt-A Mortgage Loans" includes Mortgage Loans with terms to maturity in excess of 20 years.

"Category II Alt-A Mortgage Loans" includes Mortgage Loans with terms to maturity of less than or equal to 20 years.

Under a program available to eligible borrowers who meet certain underwriting criteria and for which program a minimum down payment of only 3% is required, Alt-A Mortgage Loans may be originated with Loan-to-Value Ratios between 95.01% and 97% with the application of less restrictive maximum qualifying ratios of borrower monthly housing debt or total monthly debt obligations to borrower monthly income and reduced minimum requirements for primary mortgage insurance coverage ("3% Solution Loans"). In addition, under a program available to eligible borrowers who meet certain underwriting criteria and for which program no down payment is required, Alt-A Mortgage Loans may be originated with Loan-to-Value Ratios of 100%; provided that the property related to such Mortgage Loans is a single unit primary residence.

With respect to mortgaged property types, mortgage loans may be secured by shares in cooperative housing corporations, manufactured homes, investment properties permitted under less stringent guidelines, condotels (features of which may include maid service, a front desk or resident manager, rental pools and up to 20% of commercial space), and the mortgaged properties may represent an unusually high percentage of land vs. structure or have other unique characteristics.

In connection with its Alt-A Minus program in effect prior to July 10, 2006, Wells Fargo Bank established classifications with respect to the credit profile of the applicant, and each loan was placed into one of thirteen credit levels denoted as "F9 through F1," with certain levels subdivided by Stated Reduced, as described in the table below. Terms of mortgage loans originated by Wells Fargo Bank under the Alt-A Minus program, as well as maximum Loan-to-Value Ratios, vary depending on the credit level classification of the applicant. Loan applicants with less favorable credit profiles generally were restricted to consideration for loans with higher interest rates, lower maximum loan amounts and lower Loan-to-Value Ratios than applicants with more favorable credit profiles. Except for loans originated under the "No Ratio" program, the maximum total Debt-to-Income Ratio for each credit level is generally 50%. "Debt-to-Income Ratio" is the ratio, expressed as a percentage, of (i) the amount of the monthly debt obligations (including the proposed new housing payment and related expenses such as, but not

-43-

limited to, property taxes and insurance) over (ii) the mortgagor's gross monthly income, as of the origination of the Mortgage Loan. Subject to the consideration of certain compensating factors, the general criteria used by Wells Fargo Bank's underwriting staff in classifying loan applicants were as follows:

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                                                                                                                    Maximum
      Credit                        Existing Mortgage                    Documentation                           Combined Loan
       Level                             History                             Type            FICO Score(1)     to Value Ratio(2)
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F9                   2 x 30;  Mortgage or rent payments no more than  No documentation        700 or higher        95% CLTV @
                     30 days late at application  time and a maximum                                               LTV < 95%
                     of two  30-day  late  payments  in the  last 12
                            months
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F8                   2 x 30;  Mortgage or rent payments no more than  No documentation        660-699              95% CLTV @
                     30 days late at application  time and a maximum                                               LTV <95%
                     of two  30-day  late  payments  in the  last 12
                            months
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F7                   0 x 30;  Mortgage or rent payments no more than  No documentation        620-659              95% CLTV @
                     30 days late at application  time and no 30-day                                               LTV <95%
                     late payments in the last 12 months
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F6                   2 x 30;  Mortgage or rent payments no more than  Stated with option      700 or higher        95% CLTV @
                     30 days late at application  time and a maximum  of verification of                           LTV <95%
                     of two  30-day  late  payments  in the  last 12  assets; maximum
                            months                                    Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F6 Stated Reduced    1 x 30;  Mortgage or rent payments no more than  Stated with option      700 or higher        95% CLTV @
                     30 days late at application  time and a maximum  of verification of                           LTV <80%
                     of one  30-day  late  payment  in the  last  12  assets; maximum
                            months                                    Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F5                   2 x 30;  Mortgage or rent payments no more than  Stated with option      660-699              95% CLTV @
                     30 days late at application  time and a maximum  of verification of                           LTV <95%
                     of two  30-day  late  payments  in the  last 12  assets; maximum
                            months                                    Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F5 Stated Reduced    1 x 30;  Mortgage or rent payments no more than  Stated with option      660-699              95% CLTV @
                     30 days late at application  time and a maximum  of verification of                           LTV <80%
                     of one  30-day  late  payment  in the  last  12  assets; maximum
                            months                                    Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F4                   0 x 30;  Mortgage or rent payments no more than  Stated with option      640-659              95% CLTV @
                     30 days late at application  time and no 30-day  of verification of                           LTV <95%
                     late payments in the last 12 months              assets; maximum
                                                                      Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F4 Stated Reduced    1 x 30;  Mortgage or rent payments no more than  Stated with option      640-659              95% CLTV @
                     30 days late at application  time and a maximum  of verification of                           LTV <80%
                     of one  30-day  late  payment  in the  last  12  assets; maximum
                            months                                    Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F3                   0 x 30;  Mortgage or rent payments no more than  Stated with option      620-639              95% CLTV @
                     30 days late at application  time and no 30-day  of verification of                           LTV <95%
                     late payments in the last 12 months              assets; maximum
                                                                      Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F3 Stated Reduced    1 x 30;  Mortgage or rent payments no more than  Stated with option      620-639              95% CLTV @
                     30 days late at application  time and a maximum  of verification of                           LTV <80%
                     of one  30-day  late  payment  in the  last  12  assets; maximum
                            months                                    Debt-to-Income
                                                                        Ratio of 50%
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F2                   2 x 30;  Mortgage or rent payments no more than  No Ratio with           600 or higher        95% CLTV @
                     30 days late at application  time and a maximum  option of                                    LTV <95%
                     of two  30-day  late  payments  in the  last 12  verification of
                            months                                    assets
-------------------  -----------------------------------------------  -------------------  -----------------  -------------------
F1                   0 x 30;  Mortgage or rent payments no more than  No Ratio with           620-659              95% CLTV @
                     30 days late at application  time and no 30-day  option of                                    LTV <95%
                     late payments in the last 12 months              verification of
                                                                      assets


(1) Lower of two, middle of three FICO Scores used. If only one FICO Score is obtained, then that score is used.

(2) The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios are subject to downward adjustment based upon a number of factors including without limitation, mortgage loan amount, the mortgage loan program, the purpose of the mortgage loan, the level of documentation, the type of mortgaged property and whether or not the mortgaged property is owner-occupied. In addition, the Combined Loan-to-Value Ratio only reflects simultaneous secondary financing provided by Wells Fargo Bank or of which Wells Fargo Bank is aware at the time of funding of the related mortgage loan. Wells Fargo Bank does not restrict a borrower from obtaining secondary financing after the origination of a mortgage loan. 100% CLTV allowed when verification of assets option chosen, with loan amounts less than or equal to $500,000 and LTV less than or equal to 80%.

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For the purpose of assigning (a) the credit levels designated as Stated Reduced in the table above, consecutive monthly payments having the same delinquency characterization (e.g., 30-day late or 60-day late) were counted as a single late payment of such delinquency characterization and (b) the credit levels other than those designated as Stated Reduced in the table above, consecutive monthly payments having the same delinquency characterization (e.g., 30-day late or 60-day late) are each counted as an additional occurrence of such delinquency characterization. Wells Fargo Bank used the foregoing categories and characteristics as guidelines only.

The Mortgage Loans originated or acquired by Wells Fargo Bank under the Alt-A Minus program before July 10, 2006 had loan terms of 15, 20 or 30 years and fully amortize over such terms and the principal amounts generally ranged from a minimum of $10,000 to a maximum of $1,000,000. Wells Fargo Bank generally did not originate or acquire any Mortgage Loans under the Alt-A Minus program before July 10, 2006 for which the Loan-to-Value Ratio at origination exceeded 100% or for which the Combined Loan-to-Value Ratio at origination exceeded 100% in the event of concurrent secondary financing. The Mortgage Loans originated or acquired by Wells Fargo Bank under the Alt-A Minus program before July 10, 2006 are generally secured by single-family detached residences, condominium units or two-to four-family residences, and such properties may or may not be occupied by the owner. It was Wells Fargo Bank's policy not to accept commercial properties or unimproved land as collateral for Mortgage Loans originated under the Alt-A Minus program before July 10, 2006. Wells Fargo Bank, may have, however, accepted mixed-use properties such as a property where more than 80% is used for residential purposes and the balance is used for commercial purposes.

The Alt-A Minus program before July 10, 2006 includes No Ratio documentation program, No Documentation program, Stated documentation program and Stated Reduced documentation program.

Under the EFA Program, Wells Fargo Bank revised its underwriting program to include expanded credit score requirements and Loan-to-Value Ratios and Combined Loan-to-Value Ratios, higher loan amounts and more documentation types and property types. The Mortgage Loans originated or acquired by Wells Fargo Bank under the EFA Program include the following: Fixed Rate Loans with terms of 15, 20 or 30 years which fully amortize over such terms; 30 and 40-year Balloon Loans; and various types of adjustable-rate mortgage loans. There is no minimum loan amount for Mortgage Loans originated or acquired by Wells Fargo Bank under the EFA Program (except for Correspondent Loans, which have a minimum loan amount of $50,000) and the maximum loan amounts are $6,000,000 for Alt-A Prime and $4,000,000 for Alt-A Minus.

Wells Fargo Bank implemented more conservative underwriting criteria with respect to Alt-A Minus Mortgage Loans with loan applications taken on or after February 16, 2007 and April 9, 2007. As a result of the changes implemented, underwriting criteria applicable to a Mortgage Loan may differ depending on the channel through which the loan was originated. Wells Fargo Bank originates loans through (a) its wholesale channel, which is comprised of third-party mortgage brokers who originate mortgage loans pursuant to Wells Fargo Bank's underwriting standards (such mortgage loans, "Wholesale Loans"), (b) its retail channel, which is comprised of a network of branch offices (such mortgage loans, "Retail Loans") and (c) its Correspondents (such mortgage loans, "Correspondent Loans"). Unless otherwise specified herein, the descriptions of the underwriting criteria apply to loans originated through all origination channels.

In addition, Wells Fargo Bank implemented more conservative underwriting criteria with respect to Alt-A Prime Mortgage Loans with loan applications taken on or after August 15, 2007, September 21, 2007 and September 22, 2007. The significant changes resulting from the implementation of these more conservative underwriting criteria are described herein.

To be eligible for Alt-A Prime, a borrower must have (i) a minimum FICO Score of 680 and (ii) a mortgage or rent history with (a) no mortgage or rent payments 30 days late at application time, (b) no mortgage or rent payments 60 days late in the last twelve months, (c) no more than two 30-day late mortgage or rent payments in the last twelve months and (d) no rolling late payments. In addition, for loan applications taken on or after August 15, 2007, to be eligible for Alt-A Prime (a) if a mortgage loan is an Interest Only Mortgage Loan, it must be originated under either the Full or Stated documentation program and (b) if the related Mortgaged Property experiences a large increase in property value over a short period of time, the borrower must provide additional documentation (such as a more detailed appraisal) supporting an increase in property value. In addition, for loan applications taken on or after September 21, 2007, Alt-A Prime Mortgage Loans are subject to a maximum loan amount of $2,000,000 and

46

must be originated under either the Full Documentation program or the Stated documentation program. To be eligible for Alt-A Minus, a borrower must have (i) a minimum FICO Score of 620 provided that Wholesale and Correspondent Loans originated under any documentation program other than the Full documentation program must have a minimum FICO Score of 640 and (ii) a mortgage or rent history with (a) no mortgage or rent payments 30 days late at application time,
(b) no mortgage or rent payments 60-days late in the last twelve months, (c) no more than two 30-day late mortgage or rent payments in the last twelve months and (d) no more than six rolling late payments for delinquencies no longer than 30 days. Wells Fargo Bank generally does not originate or acquire any Mortgage Loans under the EFA Program for which the Loan-to-Value Ratio at origination exceeds 100% or for which the Combined Loan-to-Value Ratio at origination exceeds 100% in the event of concurrent secondary financing. The Mortgage Loans originated or acquired by Wells Fargo Bank under the EFA Program are generally secured by single-family detached residences, planned unit developments, condotels, condominium units, unwarrantable condominium units or two-to four-family residences, and such properties may or may not be occupied by the owner; provided however, that for Alt-A Minus Mortgage Loans with loan applications taken on or after February 16, 2007, First Time Home Buyers are limited to one- or two-unit primary residences. In addition, for Alt-A Mortgage Loans with loan applications taken on or after April 9, 2007, First Time Home Buyers must show a satisfactory payment history. It is Wells Fargo Bank's policy not to accept commercial properties or unimproved land as collateral for Mortgage Loans originated under the EFA Program. However, Wells Fargo Bank will accept mixed-use properties such as a property where more than 80% is used for residential purposes and the balance is used for commercial purposes. In addition, for Alt-A Mortgage Loans with loan applications taken on or after April 9, 2007 that are Retail Loans (a) if the property is non-owner occupied or a second home, minimum loan amounts apply, (b) if the property is non-owner occupied and the purpose is equity take out refinance, the borrower must show a history of property ownership for twelve months and a borrower is permitted a maximum of two purchases or re-financings in the previous twelve months and (c) if the Loan-to-Value Ratio and Combined Loan-to-Value Ratio is 100%, there is a minimum FICO Score of 640.

A "First Time Home Buyer" is a borrower who has not had an ownership interest in a property in the last 36 months.

The EFA program includes No Ratio Loans with a borrower's option to verify assets, Stated Loans with a borrower's option to verify assets, Full Documentation Loans and No Documentation Loans.

The following table sets forth the different documentation types, occupancy types, maximum loan amounts and maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for the Alt-A Prime and Alt-A Minus Mortgage Loans relating to one to four family residences, condominiums and units within planned unit developments that are originated under the EFA Program:

                                                                                                       Maximum Combined
                                              Occupancy          Maximum        Maximum Loan to         Loan to Value
 Credit Level       Documentation Type          Type           Loan Amount       Value Ratio(1)            Ratio(1)
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        Full                     Owner               $6,000,000            100%                   100%
                                            occupied
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        Full                     Second home        $6,000,000(2)          95%                    100%
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        Full                     Non-owner           $4,000,000            90%                    100%
                                            occupied
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        Stated with option       Owner               $6,000,000            95%                    100%
                   of verification of       occupied
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        Stated with option       Second home        $6,000,000(2)          90%                    90%
                   of verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        Stated with option       Non-owner           $4,000,000            90%                    90%
                   of verification of       occupied
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        No Ratio with            Owner               $4,000,000            95%                    100%
                   option of                occupied
                   verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        No Ratio with            Second home        $4,000,000(2)          90%                    90%
                   option of
                   verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        No Ratio with            Non-owner           $3,000,000            90%                    90%
                   option of                occupied
                   verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        No Documentation         Owner               $3,000,000            95%                    95%
                                            occupied
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        No Documentation         Second home         $3,000,000            80%                    80%

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                                                                                                       Maximum Combined
                                              Occupancy          Maximum        Maximum Loan to         Loan to Value
 Credit Level       Documentation Type          Type           Loan Amount       Value Ratio(1)            Ratio(1)
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Prime        No Documentation         Non-owner           $1,000,000            75%                    75%
                                            occupied
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        Full                     Owner               $4,000,000            100%                   100%
                                            occupied(3)
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        Full                     Second              $4,000,000            95%                    100%
                                            home(3)
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        Full                     Non-owner           $3,000,000         80%/85%(4)                100%
                                            occupied
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        Stated with option       Owner               $4,000,000            95%                    100%
                   of verification of       occupied(3)
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        Stated with option       Second              $2,000,000            90%                    90%
                   of verification of       home(3)
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        Stated with option       Non-owner           $2,000,000         80%/85%(4)                90%
                   of verification of       occupied
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        No ratio with            Owner               $4,000,000            95%                    100%
                   option of                occupied(3)
                   verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        No ratio with            Second             $2,000,000(2)          90%                    90%
                   option of                home(3)
                   verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        No ratio with            Non-owner           $1,000,000         80%/85%(4)                90%
                   option of                occupied
                   verification of
                   assets
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        No Documentation         Owner               $2,000,000            95%                    95%
                                            occupied(3)
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        No Documentation         Second             $2,000,000(2)          75%                    75%
                                            home(3)
---------------    ---------------------    --------------     -------------    -----------------    ---------------------
Alt-A Minus        No Documentation         Non-owner            $750,000             75%                    75%
                                            occupied


(1) The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios are subject to downward adjustment based upon a number of factors including without limitation, mortgage loan amount, the purpose of the mortgage loan and the type of mortgaged property. In addition, the Combined Loan-to-Value Ratio only reflects simultaneous secondary financing provided by Wells Fargo Bank or of which Wells Fargo Bank is aware at the time of funding of the related first lien Mortgage Loan. Wells Fargo Bank does not restrict a borrower from obtaining secondary financing after the origination of the first lien Mortgage Loan. The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for Alt-A Minus Mortgage Loans with loan applications taken on or after (a) February 16, 2007 that are considered higher risk transactions are subject to downward adjustment and
(b) April 6, 2007 is 95% for Correspondent Loans. In addition, the maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for Alt-A Prime Mortgage Loans with loan applications taken on or after September 22, 2007 are subject to a 5% reduction, subject to certain exceptions if certain enhanced appraisal requirements are met, if a Mortgaged Property has a Loan-to-Value Ratio and Combined Loan to-Value Ratio of greater than 80% and is located in an area that Wells Fargo Bank determines has been impacted by significant property value declines. In addition, as a result of the guideline changes on August 15, 2007, Wells Fargo Bank expanded the criteria used to determine if an area is considered to be a rural area and therefore subject to lower maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios.

(2) The maximum loan amounts are subject to downward adjustment based upon certain factors including property type and purpose of the mortgage loan.

(3) For Alt-A Minus Mortgage Loans with loan applications taken on or after February 16, 2007, three- to four-unit owner occupied and three- to four-unit second homes must be originated under the Full documentation program. For Alt-A Minus Mortgage Loans with loan applications taken on or after February 16, 2007, non-owner occupied three- to four-unit properties can be originated with all documentation types.

(4) For Alt-A Minus Mortgage Loans with loan applications taken on or after February 16, 2007, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio is 80% for Wholesale and Correspondent Loans and 85% for Retail Loans.

The following loan purposes are permitted for one to four family residences, condominiums and units within planned unit developments: purchase, rate/term refinance and cash-out refinance.

48

The following table sets forth the different documentation types, occupancy types, maximum loan amounts and maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for the Alt-A Prime and Alt-A Minus Mortgage Loans relating to cooperative units that are originated under the EFA Program:

                                                                       Maximum
                                                 Maximum Loan       Loan-to-Value           Maximum Combined
  Documentation Type         Occupancy Type         Amount             Ratio(1)          Loan-to-Value Ratio(1)
------------------------    -----------------    --------------    -----------------     -----------------------
Full                        Owner occupied        $1,000,000             80%                      80%
------------------------    -----------------    --------------    -----------------     -----------------------
Full                        Second home           $1,000,000             80%                      80%
------------------------    -----------------    --------------    -----------------     -----------------------
Full                        Non-owner             $1,000,000             80%                      80%
                            occupied
------------------------    -----------------    --------------    -----------------     -----------------------
Stated with option of       Owner occupied        $1,000,000             75%                      75%
verification of assets
------------------------    -----------------    --------------    -----------------     -----------------------
Stated with option of       Second home           $1,000,000             75%                      75%
verification of assets
------------------------    -----------------    --------------    -----------------     -----------------------
Stated with option of       Non-owner             $1,000,000             75%                      75%
verification of assets      occupied
------------------------    -----------------    --------------    -----------------     -----------------------
No Ratio with option        Owner occupied        $1,000,000             70%                      N/A
of verification of
assets
------------------------    -----------------    --------------    -----------------     -----------------------
No Ratio with option        Second home           $1,000,000             70%                      N/A
of verification of
assets
------------------------    -----------------    --------------    -----------------     -----------------------
No Ratio with option        Non-owner             $1,000,000             70%                      N/A
of verification of          occupied
assets


(1) The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios are subject to downward adjustment based upon a number of factors including without limitation, mortgage loan amount. In addition, the Combined Loan-to-Value Ratio only reflects simultaneous secondary financing provided by Wells Fargo Bank or of which Wells Fargo Bank is aware at the time of funding of the related first lien Mortgage Loan. Wells Fargo Bank does not restrict a borrower from obtaining secondary financing after the origination of the first lien Mortgage Loan. Secondary financing is only available for full documentation and stated documentation with option of verification of assets. The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for Alt-A Minus Mortgage Loans with loan applications taken on or after (a) February 16, 2007 that are considered higher risk transactions are subject to downward adjustment and (b) April 6, 2007 is 95% for Correspondent Loans. In addition, the maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for Alt-A Prime Mortgage Loans with loan applications taken on or after September 22, 2007 are subject to a 5% reduction, subject to certain exceptions if certain enhanced appraisal requirements are met, if a Mortgaged Property has a Loan-to-Value Ratio and Combined Loan to-Value Ratio of greater than 80% and is located in an area that Wells Fargo Bank determines has been impacted by significant property value declines. In addition, as a result of the guideline changes on August 15, 2007, Wells Fargo Bank expanded the criteria used to determine if an area is considered to be a rural area and therefore subject to lower maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios.

The following loan purposes are permitted for cooperative units: purchase and rate/term refinance.

The following table sets forth the different documentation types, occupancy types, maximum loan amounts and maximum Loan-to-Value Ratios for the Alt-A Prime and Alt-A Minus Mortgage Loans relating to condotels that are originated under the EFA Program:

                                                                                  Maximum
                                                                               Loan-to-Value
  Documentation Type         Occupancy Type        Maximum Loan Amount           Ratio(1)
-----------------------    --------------------    ---------------------    --------------------
Full                       Owner occupied               $1,000,000                  80%
-----------------------    --------------------    ---------------------    --------------------
Full                       Second home                  $1,000,000                  80%
-----------------------    --------------------    ---------------------    --------------------
Full                       Non-owner occupied           $1,000,000                  80%
-----------------------    --------------------    ---------------------    --------------------
Stated with option of      Owner occupied               $1,000,000                  75%
verification of assets
-----------------------    --------------------    ---------------------    --------------------
Stated with option of      Second home                  $1,000,000                  75%
verification of assets
-----------------------    --------------------    ---------------------    --------------------
Stated with option of      Non-owner occupied           $1,000,000                  75%
verification of assets
-----------------------    --------------------    ---------------------    --------------------
No Ratio with option       Owner occupied               $1,000,000                  70%
of verification of
assets

49

                                                                                  Maximum
                                                                               Loan-to-Value
  Documentation Type         Occupancy Type        Maximum Loan Amount           Ratio(1)
-----------------------    --------------------    ---------------------    --------------------
No Ratio with option       Second home                  $1,000,000                  70%
of verification of
assets
-----------------------    --------------------    ---------------------    --------------------
No Ratio with option       Non-owner occupied           $1,000,000                  70%
of verification of
assets


(1) The maximum Loan-to-Value Ratios are subject to downward adjustment based upon a number of factors including without limitation, mortgage loan amount. Secondary financing is not available for condotels.

The following loan purposes are permitted for condotels: purchase and rate/term refinance.

The following table sets forth the different documentation types, occupancy types, maximum loan amounts and maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for the Alt-A Prime and Alt-A Minus Mortgage Loans for which the borrower is a foreign national that are originated under the EFA Program:

                                                                      Maximum
                                                Maximum Loan       Loan-to-Value           Maximum Combined
  Documentation Type      Occupancy Type(1)        Amount             Ratio(2)          Loan-to-Value Ratio(2)
----------------------    -----------------    --------------    -----------------     -----------------------
Full                      Owner occupied         $1,000,000             80%                     80%
----------------------    -----------------    --------------    -----------------     -----------------------
Full                      Second home            $1,000,000             80%                     80%
----------------------    -----------------    --------------    -----------------     -----------------------
Stated with option        Owner occupied         $1,000,000             75%                     75%
of verification of
assets
----------------------    -----------------    --------------    -----------------     -----------------------
Stated with option        Second home            $1,000,000             75%                     75%
of verification of
assets
----------------------    -----------------    --------------    -----------------     -----------------------
No Ratio with option      Owner occupied         $1,000,000             75%                     75%
of verification of
assets(3)
----------------------    -----------------    --------------    -----------------     -----------------------
No Ratio with option      Second home            $1,000,000             75%                     75%
of verification of
assets(3)


(1) Property types permitted include one to four family residence, condominiums and units within planned unit developments; provided however, that three and four family residences are not permitted for second homes.

(2) The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios are subject to downward adjustment based upon a number of factors including without limitation, mortgage loan amount. In addition, the Combined Loan-to-Value Ratio only reflects simultaneous secondary financing provided by Wells Fargo Bank or of which Wells Fargo Bank is aware at the time of funding of the related first lien Mortgage Loan. Wells Fargo Bank does not restrict a borrower from obtaining secondary financing after the origination of the first lien Mortgage Loan. Secondary financing is only available for full documentation and stated documentation with option of verification of assets. The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios are reduced by 5% for borrowers without a FICO Score. The maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for Alt-A Minus Mortgage Loans with loan applications taken on or after (a) February 16, 2007 that are considered higher risk transactions are subject to downward adjustment and (b) April 6, 2007 is 95% for Correspondent Loans. In addition, the maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios for Alt-A Prime Mortgage Loans with loan applications taken on or after September 22, 2007 are subject to a 5% reduction, subject to certain exceptions if certain enhanced appraisal requirements are met, if a Mortgaged Property has a Loan-to-Value Ratio and Combined Loan to-Value Ratio of greater than 80% and is located in an area that Wells Fargo Bank determines has been impacted by significant property value declines. In addition, as a result of the guideline changes on August 15, 2007, Wells Fargo Bank expanded the criteria used to determine if an area is considered to be a rural area and therefore subject to lower maximum Loan-to-Value Ratios and Combined Loan-to-Value Ratios.

(3) Borrowers with no FICO Score are not eligible for No Ratio with option of verification of assets.

The following loan purposes are permitted for mortgage loans for which the borrower is a foreign national: purchase and rate/term refinance.

Borrowers who satisfy certain guidelines regarding credit history may have been approved under the "No Ratio" documentation program (such Mortgage Loans, "No Ratio Loans") or under the "No Documentation"

50

program (such Mortgage Loans, "No Documentation Loans"). In the case of No Ratio Loans, the borrower's would not have been required to provide any information in the loan application regarding their income nor would there have been the calculation of any ratios, as part of the loan underwriting decision, of the borrower's expected monthly housing debt or total monthly debt obligations to the borrower's monthly income; provided however that the source of income and the source and amount of assets are stated on the application. In connection with such No Ratio program, the borrower has the option to verify assets and certain minimum "cash reserves" are required. In addition, in some instances a verification of the borrower's employment may have been obtained. Under the No Ratio program, for Alt-A Minus Mortgage Loans with loan application taken on or after February 16, 2007 (i) the borrower must be self employed, (ii) if the property is non-owner occupied, the assets of the borrower must be verified,
(iii) housing payment history is required for First Time Home Buyers and (iv)
(a) if the mortgage loan is a Wholesale or Correspondent Loan and the borrower has a FICO Score of 620-679, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted is 80%, (b) if the mortgage loan is a Retail Loan and the borrower has a FICO Score of 640-679, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted is 85% and (c) if the borrower has a FICO Score of 680 or higher, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted is 85% for Wholesale and Correspondent Loans and 90% for Retail Loans. In the case of the No Documentation program, borrowers may not have been required to provide any information in their loan application regarding their employment and in that instance employment would not have been verified. Also, in the case of the No Documentation program, borrowers would not have been required to provide any information in their loan application regarding their income or assets. For Mortgage Loans with loan applications taken on or after February 16, 2007, the No Documentation program is not available for Alt-A Minus Mortgage Loans.

In the case of the "Stated" documentation program (such Mortgage Loans, "Stated Loans"), the borrower's income would not have been verified and the borrower has the option to verify assets and certain minimum "cash reserves" are required. Under the Stated program the borrower's employment, income sources and assets must be stated on the signed loan application. The borrower's income as stated must be reasonable for the borrower's occupation as determined at the discretion of the loan underwriter. Similarly, the borrower's assets as stated must be reasonable for the borrower's income as determined at the discretion of the loan underwriter. Under the Stated documentation program, for Alt-A Minus Mortgage Loans with loan application taken on or after February 16, 2007 (i) the borrower must be self employed, (ii) if the property is non-owner occupied, the assets of the borrower must be verified and (iii) (a) if the mortgage loan is a Wholesale or Correspondent Loan and the borrower has a FICO Score of 620-679, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted is 80%, (b) if the mortgage loan is a Retail Loan and the borrower has a FICO Score of 640-679, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted is 85% and (c) if the borrower has a FICO Score of 680 or higher, the maximum Loan-to-Value Ratio and Combined Loan-to-Value Ratio permitted is 85% for Wholesale and Correspondent Loans and 90% for Retail Loans. For Alt-A Minus Mortgage Loans with loan application taken on or after April 6, 2007 originated under the Stated documentation program, certain reserve requirements must be met if the Loan-to-Value Ratio and Combined Loan-to-Value Ratio is greater than 90% or the loan amount is over $450,000.

In connection with its Alt-A Minus program in effect prior to July 10, 2006, in certain circumstances borrowers who did not qualify for other reduced documentation programs may have qualified for the "Stated Reduced" documentation program (such Mortgage Loans, "Stated Reduced Loans"). Maximum Loan-to-Value Ratios are lower under the Stated Reduced program than for other reduced documentation programs. In the case of the Stated Reduced documentation program, the borrower's income would not have been verified, the borrower's assets may have been verified and certain minimum "cash reserves" required. Under the Stated Reduced program the borrower's employment, income sources and assets must be stated on the signed loan application. The borrower's income as stated must be reasonable for the borrower's occupation as determined in the discretion of the loan underwriter. Similarly, the borrower's assets as stated must be reasonable for the borrower's occupation as determined in the discretion of the loan underwriter. The Stated Reduced program is not available for any mortgage loans originated under the guidelines of the EFA Program.

In the case of the "Full" documentation program (such Mortgage Loans, "Full Documentation Loans"), all sections of the mortgage loan application must be complete with borrower's employment, income and assets. A minimum of two years of continuous employment or source of income must be disclosed for each borrower. Generally, self-employed borrowers should have at least a two year history in the same business in the same market

51

area and must provide previous year's W-2 and current pay stub with year-to-date earnings or, if unavailable, must provide previous year's tax return. For loans originated under the Full Documentation program, a verbal verification of employment is required and assets must be disclosed, documented and verified. In addition, Full Documentation Loans are subject to a maximum Debt-to-Income Ratio of 55%. For Alt-A Minus Mortgage Loans with loan application taken on or after April 6, 2007 originated under the Full Documentation program, certain reserve requirements must be met if the Loan-to-Value Ratio and Combined Loan-to-Value Ratio is greater than 90% or the loan amount is over $450,000.

Wells Fargo Bank's underwriting of every Alt-A Mortgage Loan submitted (as to which underwriting authority has not been delegated) consists of a credit review. In addition, Wells Fargo Bank's underwriting of every Alt-A Mortgage Loan submitted consists of a separate appraisal conducted by (i) a third-party appraiser, (ii) an appraiser approved by RELS, or (iii) RELS itself. Appraisals generally conform to current Fannie Mae and Freddie Mac secondary market requirements for residential property appraisals. All appraisals are subject to an internal appraisal review irrespective of the Loan-to-Value Ratio, the amount of the Mortgage Loan or the identity of the appraiser. Certain loans require a third party review in the form of either a desk review or field review. At the discretion of Wells Fargo Bank, each Mortgage Loan is subject to further review in the form of a desk review, field review or additional full appraisal.

STATIC POOL INFORMATION

Historical delinquency, cumulative loss and prepayment information for various "asset types" is available via a website established by Wells Fargo Bank. Such static pool performance information will relate to either (1) prior residential mortgage loan pools securitized by Wells Fargo Bank in registered offerings through the Depositor's WFALT program or (2) prior originations of, or purchases by, Wells Fargo Bank of residential mortgage loans based on the vintage years of such prior originations or purchases. In the case of prior originations or purchases, such mortgage loans will not include any loans sold to Fannie Mae or Freddie Mac and certain mortgage loans serviced for the Federal Home Loan Banks, mortgage loans insured or guaranteed by the Government National Mortgage Association, the Federal Housing Administration or the Department of Veterans Affairs or mortgage loans sold by Wells Fargo Bank which are no longer serviced by Wells Fargo Bank. Such static pool performance information will be accompanied by a summary of original characteristics of the prior securitized pools or prior originations or purchases. Each prospectus supplement for a Series will provide the website and instructions regarding where an investor can find information relating to the specific asset type or types included in the applicable Trust or, if the Trust contains Mortgage Certificates, the asset types included in the trust underlying such Mortgage Certificates. There can be no assurance that the information provided in the website will be representative of the results that may be experienced with respect to the Mortgage Loans included in a Trust Estate containing Mortgage Loans or, if the Trust Estate contains Mortgage Certificates, any underlying Trust Estate.

THE DEPOSITOR

Wells Fargo Asset Securities Corporation (the "Depositor") is a direct, wholly owned subsidiary of Wells Fargo Bank and an indirect, wholly owned subsidiary of Wells Fargo & Company. The Depositor was incorporated in the State of Delaware on March 28, 1996 as Norwest Asset Securities Corporation. On April 7, 2000, Norwest Integrated Structured Assets, Inc., an affiliate of the Depositor, was merged into and with the Depositor. On April 17, 2000, the Depositor changed its name from Norwest Asset Securities Corporation to Wells Fargo Asset Securities Corporation.

The limited purposes of the Depositor are, in general, to acquire, own and sell mortgage loans; to issue, acquire, own, hold and sell mortgage pass-through securities and home equity asset-backed pass-through securities which represent ownership interests in mortgage loans, collections thereon and related properties; and to engage in any acts which are incidental to, or necessary, suitable or convenient to accomplish, the foregoing.

The Depositor maintains its principal office at 8480 Stagecoach Circle, Frederick, MD 21701. Its telephone number is (240) 586-5999.

52

At the time of the formation of any Trust Estate, the Depositor will be the sole owner of all the related Mortgage Loans and/or Mortgage Certificates. The Depositor will have acquired (i) the Mortgage Loans included in any Trust Estate from Wells Fargo Bank and/or (ii) the Mortgage Certificates included in any Trust Estate from Wells Fargo Bank or one or more other entities named in the prospectus supplement. The Depositor will have limited obligations and rights under the applicable Agreement after the Closing Date for any Series, including but not limited to, repurchasing or substituting Mortgage Assets in a Trust Estate in the event of defective documentation or upon the breach of certain representations and warranties made by the Depositor, and repurchasing at its option, certain defaulted Mortgage Loans or, in the circumstances described under "The Pooling and Servicing Agreement--Termination; Optional Purchase of Mortgage Loans," repurchasing all or a portion of the Mortgage Assets of a Series.

The applicable Agreement will also provide that neither the Depositor nor any subcontractor, nor any director, officer, employee or agent of the Depositor, will be under any liability to the Trust Estate or the Certificateholders, for the taking of any action or for refraining from the taking of any action in good faith pursuant to the applicable Agreement, or for errors in judgment; provided, however, that neither the Depositor, any subcontractor, nor any such person will be protected against any liability that would otherwise be imposed by reason of willful misfeasance, bad faith or gross negligence in the performance of his or its duties or by reason of reckless disregard of his or its obligations and duties thereunder. The applicable Agreement will further provide that the Depositor, any subcontractor, and any director, officer, employee or agent of the Depositor shall be entitled to indemnification by the Trust Estate and will be held harmless against any loss, liability or expense incurred in connection with the performance of their duties and obligations and any legal action relating to the applicable Agreement (including any loss, liability or expense incurred in connection with the Depositor's indemnification of the Custodian), the Certificates or the Mortgage Loans of a Series (except for amounts due in connection with a breach of a representation or warranty concerning the applicable Mortgage Loans), other than any loss, liability or expense incurred by reason of willful misfeasance, bad faith or gross negligence in the performance of its duties under the applicable Agreement or by reason of reckless disregard of its obligations and duties thereunder. In addition, the applicable Agreement will provide that the Depositor will not be under any obligation to appear in, prosecute or defend any legal action unless such action is related to its duties under the applicable Agreement and, in its opinion, does not involve it in any expense or liability. The Depositor may, however, in its discretion, undertake any such action deemed by it necessary or desirable with respect to the applicable Agreement and the rights and duties of the parties thereto and the interests of the Certificateholders thereunder if the Certificateholders offer the Depositor reasonable security or indemnity against the costs, expenses and liabilities that may be incurred. In such event, the legal expenses and costs of such action and any liability resulting therefrom will be expenses, costs and liabilities of the Trust Estate and the Depositor will be entitled to be reimbursed therefor out of the Certificate Account, and any loss to the Trust Estate arising from such right of reimbursement will be allocated first to the Subordinated Certificates of a Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable Agreement.

53

DESCRIPTION OF THE CERTIFICATES

General

A separate common law trust (a "Trust") will serve as the "Issuing Entity" and issue each series (each, a "Series") of certificates (the "Certificates"). Each Series of Certificates will include one or more classes (each, a "Class"). In addition, any Class of Certificates may consist of two or more non-severable components, each of which may exhibit any of the principal or interest payment characteristics described herein with respect to a Class of Certificates. A Series may include one or more Classes of Certificates entitled, to the extent of funds available, to receive distributions from collections on the related Mortgage Assets and, to the extent specified in the applicable prospectus supplement, from any credit enhancements described in this prospectus.

Each Series of Certificates will be issued on the date specified in the applicable prospectus supplement (the "Closing Date") pursuant to (i) in the case of a Series issued by a Trust containing Mortgage Loans (or both Mortgage Loans and Mortgage Certificates), a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement") among the Depositor, the Master Servicer and the Trustee named in the applicable prospectus supplement or (ii) in the case of a Series issued by a Trust containing only Mortgage Certificates, a Trust Agreement (the "Trust Agreement," and together with the Pooling and Servicing Agreement, the "Agreements" and each, an "Agreement" ) among the Depositor, the Securities Administrator and the Trustee named in the applicable prospectus supplement.

Distributions to Certificateholders of all Series (other than the final distribution in retirement of the Certificates) will, unless another method is specified in the applicable prospectus supplement, be made by wire transfer in immediately available funds, provided the Paying Agent is furnished with appropriate wiring instructions not less than seven business days prior to the related Distribution Date. If a Certificateholder has not notified the Paying Agent with the time period set forth in the immediately preceding sentence, distributions will be made by check mailed to the address of the person entitled thereto (which in the case of Book-Entry Certificates will be Cede as nominee for DTC) as it appears on the certificate register. The final distribution in retirement of Certificates will be made only upon presentation and surrender of the Certificates at the office or agency maintained by the Paying Agent or other entity for such purpose, as specified in the final distribution notice to Certificateholders.

Each Series of Certificates will represent ownership interests in the related Trust Estate. An election may be made to treat the Trust Estate (or one or more segregated pools of assets therein) with respect to a Series of Certificates as a REMIC. If such an election is made, such Series will consist of one or more Classes of Certificates that will represent "regular interests" within the meaning of Code Section 860G(a)(1) (such Class or Classes collectively referred to as the "Regular Certificates") and one Class of Certificates with respect to each REMIC that will be designated as the "residual interest" within the meaning of Code Section 860G(a)(2) (the "Residual Certificates") representing the right to receive distributions as specified in the prospectus supplement for such Series. See "Material Federal Income Tax Consequences."

Definitive Form

Certificates of a Series that are issued in fully registered, certificated form are referred to herein as "Definitive Certificates." Distributions of principal of, and interest on, the Definitive Certificates will be made directly to holders of Definitive Certificates in accordance with the procedures set forth in the applicable Agreement. The Definitive Certificates of a Series offered hereby and by means of the applicable prospectus supplements will be transferable and exchangeable at the office or agency maintained by the Master Servicer or Securities Administrator, as certificate registrar, or such other entity for such purpose set forth in the applicable prospectus supplement. No service charge will be made for any transfer or exchange of Definitive Certificates, but the Master Servicer or Securities Administrator, as certificate registrar, or such other entity may require payment of a sum sufficient to cover any tax or other governmental charge in connection with such transfer or exchange.

In the event that an election is made to treat the Trust Estate (or one or more segregated pools of assets therein) as a REMIC, the "residual interest" thereof will be issued as a Definitive Certificate. No legal or beneficial interest in all or any portion of any "residual interest" may be transferred without the receipt by the transferor and the Master

54

Servicer or Securities Administrator, as applicable, or other entity acting as certificate registrar of an affidavit signed by the transferee stating, among other things, that the transferee (i) is not a disqualified organization within the meaning of Code Section 860E(e) or an agent (including a broker, nominee, or middleman) thereof and (ii) understands that it may incur tax liabilities in excess of any cash flows generated by the residual interest. Further, the transferee must state in the affidavit that it (x) historically has paid its debts as they have come due, (y) intends to pay its debts as they come due in the future and (z) intends to pay taxes associated with holding the residual interest as they become due. The transferor must certify to the Master Servicer or Securities Administrator, as applicable, or other entity acting as certificate registrar that, as of the time of the transfer, it has no actual knowledge that any of the statements made in the transferee affidavit are false and no reason to know that the statements made by the transferee pursuant to clauses (x), (y) and (z) of the preceding sentence are false. See "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates--Taxation of Residual Certificates--Tax-Related Restrictions on Transfer of Residual Certificates."

Book-Entry Form

General

Each Class of Certificates of a Series issued in book-entry form ("Book-Entry Certificates") initially will be represented by one or more physical certificates registered in the name of Cede & Co. ("Cede"), as nominee of The Depository Trust Company ("DTC"), which will be the "holder" or "Certificateholder" of such Certificates, as such terms are used herein. Any person acquiring an interest in a Book-Entry Certificate (a "Beneficial Owner") will hold such Certificates through DTC in the United States, or, if specified in the applicable prospectus supplement, Clearstream or Euroclear in Europe, if they are participants of such systems (the "Participants"), or indirectly through organizations which are Participants in such systems (the "Indirect Participants"). Clearstream and Euroclear will hold omnibus positions on behalf of their Participants through customers' securities accounts in Clearstream's and Euroclear's names on the books of their respective depositaries which in turn will hold such positions in customers' securities accounts in the depositaries' names on the books of DTC. Citibank will act as depositary for Clearstream and JPMorgan Chase Bank, National Association will act as depositary for Euroclear (in such capacities, individually the "Relevant Depositary" and collectively the "European Depositaries"). No Beneficial Owner will be entitled to receive a Definitive Certificate representing such person's interest in the Book-Entry Certificate, except as set forth below. Unless and until Definitive Certificates are issued under the limited circumstances described herein, all references to actions taken by Certificateholders or holders shall, in the case of the Book-Entry Certificates, refer to actions taken by DTC upon instructions from its DTC Participants, and all references herein to distributions, notices, reports and statements to Certificateholders or holders shall, in the case of the Book-Entry Certificates, refer to distributions, notices, reports and statements to DTC or Cede, as the registered holder of the Book-Entry Certificates, as the case may be, for distribution to Beneficial Owners in accordance with DTC procedures.

DTC is a limited purpose trust company organized under the laws of the State of New York, a member of the Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code and a "clearing agency" registered pursuant to Section 17A of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). DTC was created to hold securities for its participating organizations ("DTC Participants") and to facilitate the clearance and settlement of securities transactions among DTC Participants through electronic book-entries, thereby eliminating the need for physical movement of certificates. DTC Participants include securities brokers and dealers (which may include any underwriter identified in the prospectus supplement applicable to any Series), banks, trust companies and clearing corporations. Indirect access to the DTC system also is available to Indirect Participants, including banks, brokers, dealers, trust companies and other institutions that clear through or maintain a custodial relationship with a DTC Participant, either directly or indirectly.

The brokerage firm, bank, thrift institution or other financial intermediary (each, a "Financial Intermediary") that maintains a Beneficial Owner's account will record the Beneficial Owner's ownership of a Book-Entry Certificate in its records for such purpose. In turn, the Financial Intermediary's ownership of such Book-Entry Certificate will be recorded on the records of DTC (or of a DTC Participant that acts as agent for the Financial Intermediary, whose interest will in turn be recorded on the records of DTC, if the Beneficial Owner's Financial Intermediary is not a DTC Participant, and, if applicable, on the records of Clearstream or Euroclear, as appropriate).

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Beneficial Owners will receive all distributions of principal of and interest on the Book-Entry Certificates from the Paying Agent through DTC and DTC Participants. While the Book-Entry Certificates are outstanding, under the rules, regulations and procedures creating and affecting DTC and its operations (the "Rules"), DTC is required to make book-entry transfers among DTC Participants on whose behalf it acts with respect to the Book-Entry Certificates and is required to receive and transmit distributions of principal of, and interest on, the Book-Entry Certificates. Participants and Indirect Participants with whom Beneficial Owners have accounts with respect to Book-Entry Certificates are similarly required to make book-entry transfers and receive and transmit such distributions on behalf of their respective Beneficial Owners. Accordingly, although Beneficial Owners will not possess certificates representing their respective interests in the Book-Entry Certificates, the Rules provide a mechanism by which Beneficial Owners will receive distributions and will be able to transfer their interest.

Unless and until Definitive Certificates are issued, Beneficial Owners who are not Participants may transfer ownership of Book-Entry Certificates only through Participants and Indirect Participants by instructing such Participants and Indirect Participants to transfer Book-Entry Certificates, by book-entry transfer, through DTC, for the account of the purchasers of such Book-Entry Certificates, which account is maintained with their respective Participants. Under the Rules and in accordance with DTC's normal procedures, transfers of ownership of Book-Entry Certificates will be executed through DTC and the accounts of the respective Participants at DTC will be debited and credited. Similarly, the Participants and Indirect Participants will make debits or credits, as the case may be, on their records on behalf of the selling and purchasing Beneficial Owners. Beneficial Owners will not be recognized by the Paying Agent (or other transaction parties) as Certificateholders, as such term is used in the applicable Agreement, and Beneficial Owners will be permitted to exercise the rights of Certificateholders only indirectly through DTC and its DTC Participants.

Because DTC can only act on behalf of DTC Participants, who in turn act on behalf of Indirect Participants and certain banks, the ability of a Beneficial Owner to pledge Book-Entry Certificates to persons or entities that do not participate in the DTC system, or to otherwise act with respect to such Book-Entry Certificates, may be limited due to the lack of a physical certificate for such Book-Entry Certificates.

If specified in the applicable prospectus supplement, the Book-Entry Certificates will be offered globally and may be held by investors through any of DTC, Clearstream or Euroclear. These Book-Entry Certificates will be tradable as home market instruments in both the European and U.S. domestic markets. Initial settlement and all secondary trades will settle in same-day funds.

Non-U.S. holders (as described below) of Book-Entry Certificates will be subject to U.S. withholding taxes unless such holders meet certain requirements and deliver appropriate U.S. tax documents to the securities clearing organizations or their participants.

Investors electing to hold their Book-Entry Certificates through DTC with respect to such global offering will follow the settlement practices applicable to conventional eurobonds, except that there will be no temporary global security and no "lock-up" or restricted period. Investor securities custody accounts will be credited with their holdings against payment in same-day funds on the settlement date.

Investors electing to hold their Book-Entry Certificates through Clearstream or Euroclear accounts will follow the settlement procedures applicable to conventional eurobonds, except that there will be no temporary global security and no lock-up' or restricted period. Book-Entry Certificates will be credited to the securities custody accounts on the settlement date against payment in same-day funds.

Clearstream International ("Clearstream"), a Luxembourg limited liability company, was formed in January 2000 through the merger of Cedel International and Deutsche Boerse Clearing.

Clearstream is registered as a bank in Luxembourg, and as such is subject to regulation by the Institute Monetaire Luxembourgeois and the Luxembourg Monetary Authority, which supervises Luxembourg banks.

Clearstream holds securities for its customers ("Clearstream Participants") and facilitates the clearance and settlement of securities transactions by electronic book-entry transfers between their accounts. Clearstream provides various services, including safekeeping, administration, clearance and settlement of internationally traded securities and securities lending and borrowing. Clearstream also deals with domestic securities markets in several countries

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through established depository and custodial relationships. Clearstream has established an electronic bridge with Euroclear Bank S.A./N.V. as the Euroclear Operator in Brussels to facilitate settlement of trades between systems. Clearstream currently accepts over 200,000 securities issues on it books.

Clearstream's customers are world-wide financial institutions including underwriters, securities brokers and dealers, banks, trust companies and clearing corporations. Clearstream's United States customers are limited to securities brokers and dealers and banks. Currently, Clearstream has approximately 2,500 customers located in over 80 countries, including all major European countries, Canada and the United States. Indirect access to Clearstream is available to other institutions which clear through or maintain custodial relationship with an account holder of Clearstream.

The Euroclear System ("Euroclear") was created in 1968 to hold securities for its participants ("Euroclear Participants") and to clear and settle transactions between Euroclear Participants through simultaneous electronic book-entry delivery against payment, thereby eliminating the need for physical movement of certificates and any risk from lack of simultaneous transfers of securities and cash. Transactions may be settled in a variety of currencies, including United States dollars. Euroclear includes various other securities, including securities lending and borrowing and interfaces with domestic markets in several countries generally similar to the arrangements for cross-market transfers with DTC described above. Euroclear is operated by Euroclear Bank S.A./N.V. (the "Euroclear Operator"). All operations are conducted by the Euroclear Operator, and all Euroclear securities clearance accounts and Euroclear cash accounts are accounts with the Euroclear Operator. Euroclear plc establishes policy for Euroclear on behalf of Euroclear Participants. Euroclear Participants include banks (including central banks), securities brokers and dealers and other professional financial intermediaries. Indirect access to Euroclear is also available to other firms that clear through or maintain a custodial relationship with a Euroclear Participant, either directly or indirectly.

Securities clearance accounts and cash accounts with the Euroclear Operator are governed by the Terms and Conditions Governing Use of Euroclear and the related Operating Procedures of the Euroclear System and applicable Belgian law (collectively, the "Terms and Conditions"). The Terms and Conditions govern transfers of securities and cash within Euroclear, withdrawals of securities and cash from Euroclear, and receipts of payments with respect to securities in Euroclear. All securities in Euroclear are held on a fungible basis without attribution of specific certificates to specific securities clearance accounts. The Euroclear Operator acts under the Terms and Conditions only on behalf of Euroclear Participants, and has no record of or relationship with persons holding through Euroclear Participants.

Distributions on the Book-Entry Certificates will be made on each Distribution Date to Cede, as nominee of DTC. DTC will be responsible for crediting the amount of such payments to the accounts of the applicable DTC Participants in accordance with DTC's normal procedures. Each DTC Participant will be responsible for disbursing such payments to the Beneficial Owners of the Book-Entry Certificates that it represents and to each Financial Intermediary for which it acts as agent. Each such Financial Intermediary will be responsible for disbursing funds to the Beneficial Owners of the Book-Entry Certificates that it represents.

Under a book-entry format, Beneficial Owners of the Book-Entry Certificates may experience some delay in their receipt of payments, since such payments will be forwarded by the Paying Agent to Cede. Distributions with respect to Certificates held through Clearstream or Euroclear will be credited to the cash accounts of Clearstream Participants or Euroclear Participants in accordance with the relevant system's rules and procedures, to the extent received by the Relevant Depositary. Such distributions will be subject to tax reporting in accordance with relevant United States tax laws and regulations. See "Material Federal Income Tax Consequences -- Taxation of Certain Foreign Investors" and "-- Backup Withholding" herein.

DTC has advised the Depositor that, unless and until Definitive Certificates are issued, DTC will take any action the holders of the Book-Entry Certificates are permitted to take under the applicable Agreement only at the direction of one or more DTC Participants to whose DTC accounts the Book-Entry Certificates are credited, to the extent that such actions are taken on behalf of Financial Intermediaries whose holdings include such Book-Entry Certificates. Clearstream or the Euroclear Operator, as the case may be, will take any other action permitted to be taken by a Certificateholder under the applicable Agreement on behalf of a Clearstream Participant or Euroclear Participant only in accordance with its relevant rules and procedures and subject to the ability of the Relevant Depositary to effect such actions on its behalf through DTC. DTC may take actions, at the direction of the related

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DTC Participants, with respect to some Book-Entry Certificates which conflict with actions taken with respect to other Book-Entry Certificates.

Although DTC, Clearstream and Euroclear have agreed to the foregoing procedures in order to facilitate transfers of Book-Entry Certificates among Participants, they are under no obligation to perform or continue to perform such procedures and such procedures may be discontinued at any time.

None of the Depositor, the Master Servicer (if any), the Securities Administrator (if any), the Paying Agent or the Trustee will have any responsibility for any aspect of the records relating to or payments made on account of beneficial ownership interests of the Book-Entry Certificates held by Cede, as nominee for DTC, or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests. In the event of the insolvency of DTC, a Participant or an Indirect Participant in whose name Book-Entry Certificates are registered, the ability of the Beneficial Owners of such Book-Entry Certificates to obtain timely payment and, if the limits of applicable insurance coverage by the Securities Investor Protection Corporation are exceeded or if such coverage is otherwise unavailable, ultimate payment, of amounts distributable with respect to such Book-Entry Certificates may be impaired.

The Book-Entry Certificates will be converted to Definitive Certificates and reissued to Beneficial Owners or their nominees, rather than to DTC or its nominee, only if (i) the Paying Agent is advised in writing that DTC is no longer willing or able to discharge properly its responsibilities as depository with respect to the Book-Entry Certificates and the Paying Agent is unable to locate a qualified successor or (ii) after the occurrence of any other event specified in the applicable prospectus supplement.

Upon the occurrence of any event described in the immediately preceding paragraph, the Paying Agent will be required to notify all Beneficial Owners through DTC Participants of the availability of Definitive Certificates. Upon surrender by DTC of the physical certificates representing the Book-Entry Certificates and receipt of instructions for re- registration, the Paying Agent will reissue the Book-Entry Certificates as Definitive Certificates to Beneficial Owners. The procedures relating to payment on and transfer of Certificates initially issued as Definitive Certificates will thereafter apply to those Book-Entry Certificates that have been reissued as Definitive Certificates.

Secondary Market Trading

Since the purchaser determines the place of delivery, it is important to establish at the time of the trade where both the purchaser's and seller's accounts are located to ensure that settlement can be made on the desired value date.

Trading between DTC Participants. Secondary market trading between DTC Participants will be settled using the procedures applicable to prior mortgage loan asset backed certificates issues in same-day funds.

Trading between Clearstream and/or Euroclear Participants. Secondary market trading between Clearstream Participants or Euroclear Participants will be settled using the procedures applicable to conventional eurobonds in same-day funds.

Trading between DTC seller and Clearstream or Euroclear purchaser. When Book-Entry Certificates are to be transferred from the account of a DTC Participant to the account of a Clearstream Participant or a Euroclear Participant, the purchaser will send instructions to Clearstream or Euroclear through a Clearstream Participant or Euroclear Participant at least one business day prior to settlement. Clearstream or Euroclear will instruct the respective Depositary, as the case may be, to receive the Book-Entry Certificates against payment. Payment will include interest accrued on the Book-Entry Certificates from and including the last coupon payment date to and excluding the settlement date, on the basis of either a 360-day year comprised of 30-day months or the actual number of days in such accrual period and a year assumed to consist of 360 days, as applicable. For transactions settling on the 31st of the month, payment will include interest accrued to and excluding the first day of the following month. Payment will then be made by the respective Depositary of the DTC Participant's account against delivery of the Book-Entry Certificates. After settlement has been completed, the Book-Entry Certificates will be credited to the respective clearing system and by the clearing system, in accordance with its usual procedures, to the Clearstream Participant's or Euroclear Participant's account. The securities credit will appear the next day

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(European time) and the cash debt will be back-valued to, and the interest on the Book-Entry Certificates will accrue from, the value date (which would be the preceding day when settlement occurred in New York). If settlement is not completed on the intended value date (i.e., the trade fails), the Clearstream or Euroclear cash debt will be valued instead as of the actual settlement date.

Clearstream Participants and Euroclear Participants will need to make available to the respective clearing systems the funds necessary to process same-day funds settlement. The most direct means of doing so is to preposition funds for settlement, either from cash on hand or existing line of credit, as they would for any settlement occurring within Clearstream or Euroclear. Under this approach, they may take on credit exposure to Clearstream or Euroclear until the Book-Entry Certificates are credited to their accounts one day later.

As an alternative, if Clearstream or Euroclear has extended a line of credit to them, Clearstream Participants or Euroclear Participants can elect not to preposition funds and allow that credit line to be drawn upon the finance settlement. Under this procedure, Clearstream Participants or Euroclear Participants purchasing Book-Entry Certificates would incur overdraft charges for one day, assuming they cleared the overdraft when the Global Securities were credited to their accounts. However, interest on the Book-Entry Certificates would accrue from the value date. Therefore, in many cases the investment income on the Book-Entry Certificates earned during that one-day period may substantially reduce or offset the amount of such overdraft charges, although this result will depend on each Clearstream Participant's or Euroclear Participant's particular cost of funds.

Since the settlement is taking place during New York business hours, DTC Participants can employ their usual procedures for sending Book-Entry Certificates to the respective European Depositary for the benefit of Clearstream Participants or Euroclear Participants. The sale proceeds will be available to the DTC seller on the settlement date. Thus, to the DTC Participants a cross-market transaction will settle no differently than a trade between two DTC Participants.

Trading between Clearstream or Euroclear Seller and DTC Purchaser. Due to time zone differences in their favor, Clearstream Participants and Euroclear Participants may employ their customary procedures for transactions in which Book-Entry Certificates are to be transferred by the respective clearing system, through the respective Depositary, to a DTC Participant. The seller will send instructions to Clearstream or Euroclear through a Clearstream Participant or Euroclear Participant at least one business day prior to settlement. In these cases Clearstream or Euroclear will instruct the respective Depositary, as appropriate, to deliver the Book-Entry Certificates to the DTC Participant's account against payment. Payment will include interest accrued on the Book-Entry Certificates from and including the last coupon payment to and excluding the settlement date on the basis of either a 360-day year comprised of 30-day months or the actual number of days in such accrual period and a year assumed to consist of 360 days, as applicable. For transactions settling on the 31st of the month, payment will include interest accrued to and excluding the first day of the following month. The payment will then be reflected in the account of the Clearstream Participant or Euroclear Participant the following day, and receipt of the cash proceeds in the Clearstream Participant's or Euroclear Participant's account would be back-valued to the value date (which would be the preceding day, when settlement occurred in New York). Should the Clearstream Participant or Euroclear Participant have a line of credit with its respective clearing system and elect to be in debt in anticipation of receipt of the sale proceeds in its account, the back-valuation will extinguish any overdraft incurred over that one-day period. If settlement is not completed on the intended value date (i.e., the trade fails), receipt of the cash proceeds in the Clearstream Participant's or Euroclear Participant's account would instead be valued as of the actual settlement date.

Finally, day traders that use Clearstream or Euroclear and that purchase Book-Entry Certificates from DTC Participants for delivery to Clearstream Participants or Euroclear Participants should note that these trades would automatically fail on the sale side unless affirmative action was taken. At least three techniques, as set forth below, should be readily available to eliminate this potential problem.

(a) borrowing through Clearstream or Euroclear for one day (until the purchase side of the day trade is reflected in their Clearstream or Euroclear accounts) in accordance with the clearing system's customary procedures;

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(b) borrowing the Book-Entry Certificates in the U.S. from a Participant no later than one day prior to settlement, which would give the Book-Entry Certificates sufficient time to be reflected in their Clearstream or Euroclear account in order to settle the sale side of the trade; or

(c) staggering the value dates for the buy and sell sides of the trade so that the value date for the purchase from the DTC Participant is at least one day prior to the value date for the sale to the Clearstream Participant or Euroclear Participant.

Certain U.S. Federal Income Tax Documentation Requirements of Book-Entry Certificates

A Beneficial Owner of Book-Entry Certificates holding securities through Clearstream or Euroclear (or through DTC if the holder has an address outside the U.S.) will be subject to the 30% U.S. withholding tax that generally applies to payments of interest (including original issue discount) on registered debt issued by U.S. Persons, unless (i) each clearing system, bank or other financial institution that holds customers' securities in the ordinary course of its trade or business in the chain of intermediaries between such beneficial owner and the U.S. entity required to withhold tax complies with applicable certification requirements and (ii) such beneficial owner takes one of the following steps to obtain an exemption or reduced tax rate:

Exemption from non-U.S. Persons (Form W-8BEN). Beneficial Owners of Book-Entry Certificates that are non-U.S. Persons can obtain a complete exemption from the withholding tax by filing a signed Form W-8BEN (Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding). If the information shown on Form W-8BEN changes, a new Form W-8BEN must be filed within 30 days of such change.

Exemption from non-U.S. Persons with effectively connected income (Form W-8ECI). A non-U.S. Person, including a non-U.S. corporation or bank with a U.S. branch, for which the interest income is effectively connected with its conduct of a trade or business in the United States, can obtain an exemption from the withholding tax by filing Form W-8ECI (Certificate of Foreign Person's Claim for Exemption from Withholding of Tax on Income Effectively Connected with the Conduct of a Trade or Business in the United States).

Exemption or reduced rate for non-U.S. Persons resident in treaty countries (Form W-8BEN). Non-U.S. Persons that are Beneficial Owners residing in a country that has a tax treaty with the United States can obtain an exemption or reduced tax rate (depending on the treaty terms) by filing Form W-8BEN.

Exemption for U.S. Persons (Form W-9). U.S. Persons can obtain a complete exemption from the withholding tax by filing Form W-9 (Payer's Request for Taxpayer Identification Number and Certification).

U.S. Federal Income Tax Reporting Procedure. The Beneficial Owner of a Book-Entry Certificate or, in the case of a Form W-8ECI filer, his agent, files by submitting the appropriate form to the person through whom it holds (the clearing agency, in the case of persons holding directly on the books of the clearing agency). Form W-8BEN and Form W-8ECI are effective until the third succeeding calendar year from the date the form is signed.

See "Material Federal Income Tax Consequences -- Taxation of Certain Foreign Investors" and " -- Taxation of Certain Foreign Investors" in this prospectus. Neither this discussion nor the discussion under "Material Federal Income Tax Consequences" referenced above covers all aspects of U.S. Federal income tax withholding that may be relevant to foreign holders in Book-Entry Certificates. Investors are advised to consult their own tax advisors for specific tax advice concerning their purchase, holding and disposing of the Book-Entry Certificates.

Distributions to Certificateholders

General

Distributions on the Certificates will generally be made on a day specified in the applicable prospectus supplement (or, if such day is not a business day, the business day following such day) of each month, commencing with the month specified in the applicable prospectus supplement (each, a "Distribution Date"). The "Determination Date" with respect to each Distribution Date will be the day of the month specified in the

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applicable prospectus supplement. The "Cut-Off Date," if any, for a Series will be the date specified in the applicable prospectus supplement. On each Distribution Date, each holder of a Certificate of a Class will, except as described in the following sentence, be entitled to receive its Certificate's Percentage Interest of the portion of the Pool Distribution Amount (as defined below) allocated to such Class. Generally, the undivided percentage interest (the "Percentage Interest") represented by any Certificate of a Class in distributions to such Class will be equal to the percentage obtained by dividing the initial principal balance (or notional amount) of such Certificate by the aggregate initial principal balance (or notional amount) of all Certificates of such Class. The Percentage Interest for a Certificate of a Class that receives distributions pursuant to request or random lot is equal to the percentage obtained by dividing the current principal balance (or notional amount) of the Certificate by the current principal balance (or notional amount) of the Class of which the Certificate is a part.

In general, the funds available for distribution to Certificateholders of a Series of Certificates with respect to each Distribution Date for a Series issued by a Trust containing Mortgage Loans (the "Pool Distribution Amount") will be the sum of all previously undistributed payments or other receipts on account of principal (including principal prepayments and Liquidation Proceeds, if any) and interest on or in respect of the related Mortgage Loans received by the related Servicer after the Cut-Off Date (except for amounts due on or prior to the Cut-Off Date), or received by the related Servicer on or prior to the Cut-Off Date but due after the Cut-Off Date, in either case received on or prior to the business day preceding the Determination Date in the month in which such Distribution Date occurs, plus all Periodic Advances with respect to payments due to be received on the Mortgage Loans on the Due Date preceding such Distribution Date, but excluding the following:

(a) amounts received as late payments of principal or interest respecting which one or more unreimbursed Periodic Advances has been made;

(b) those portions of each payment of interest on a particular Mortgage Loan which represent (i) the Fixed Retained Yield, if any, (ii) the applicable Servicing Fee, (iii) the applicable Master Servicing Fee, (iv) the Trustee Fee, if any, and (v) any other amounts described in the applicable prospectus supplement;

(c) all amounts representing scheduled payments of principal and interest due after the Due Date occurring in the month in which such Distribution Date occurs;

(d) all principal prepayments in full, all partial principal prepayments, the principal portion of all proceeds of any Mortgage Loans or property acquired in respect thereof, or liquidated pursuant to the Pooling and Servicing Agreement, net of related expenses, including Net Partial Liquidation Proceeds and Recoveries, and other unscheduled receipts in respect of principal of the Mortgage Loans other than proceeds of a repurchase of a Mortgage Loan by the Depositor or amounts deposited by the Depositor in the Certificate Account in connection with the substitution of a Mortgage Loan (collectively, "Unscheduled Principal Receipts") that were received by the Servicers after the Unscheduled Principal Receipts Period (as described under "--Unscheduled Principal Receipts" below) relating to the Distribution Date for the applicable type of Unscheduled Principal Receipt, and all related payments of interest on such amounts;

(e) all repurchase proceeds with respect to the Mortgage Loans repurchased by the Depositor on or following the Determination Date in the month in which such Distribution Date occurs and the excess of the unpaid principal balance of any Mortgage Loan for which a Mortgage Loan was substituted over the unpaid principal balance of such substitute Mortgage Loan on or following the Determination Date in the month in which such Distribution Date occurs;

(f) that portion of Liquidation Proceeds or insurance proceeds which represents any unpaid Servicing Fees, Master Servicing Fee or any Trustee Fee to which the related Servicer, the Trustee or the Master Servicer, respectively, is entitled, any unpaid Fixed Retained Yield and any unreimbursed Periodic Advances;

(g) if an election has been made to treat the applicable Trust Estate as a REMIC, any Liquidation Profits with respect to such Distribution Date;

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(h) all amounts representing certain expenses reimbursable to the Master Servicer, the Trustee, any Servicer and other amounts permitted to be withdrawn by the Master Servicer from the Certificate Account, in each case pursuant to the applicable Pooling and Servicing Agreement;

(i) all amounts in the nature of late fees, assumption fees, prepayment fees and similar fees and payments of interest related to principal prepayments received on or after the first day of the month in which a Distribution Date occurs and prior to the Determination Date in the month of such Distribution Date which the related Servicer is entitled to retain pursuant to the applicable Underlying Servicing Agreement;

(j) reinvestment earnings on payments received in respect of the Mortgage Loans; and

(k) any amounts reimbursable to the related Servicer to cover PMI Advances.

The applicable prospectus supplement for a Series will describe any material variation in the calculation of the Pool Distribution Amount for such Series.

A "Recovery" is an amount received in respect of principal which has previously been allocated as a Realized Loss to a Class of Certificates.

"Liquidation Profits" with respect to a Distribution Date and a liquidated Mortgage Loan will be the amount, if any, by which net Liquidation Proceeds on such liquidated Mortgage Loan exceed the unpaid principal balance thereof plus accrued interest thereon at the Mortgage Interest Rate.

"Liquidation Proceeds" are all amounts received by a Servicer in connection with the liquidation of defaulted Mortgage Loans or property acquired in respect thereof, whether through foreclosure sale or otherwise, including payments in connection with defaulted Mortgage Loans received from the mortgagor other than amounts required to be paid to the mortgagor pursuant to the terms of the applicable Mortgage Loan or otherwise pursuant to law. "Partial Liquidation Proceeds" are Liquidation Proceeds received by a Servicer on a Mortgage Loan prior to such Mortgage Loan becoming a Liquidated Loan and "Net Partial Liquidation Proceeds" are Partial Liquidation Proceeds less expenses incurred with respect to such liquidation.

In general, the "Pool Distribution Amount" for each Distribution Date with respect to a Series of Certificates issued by a Trust containing Mortgage Certificates will be equal to all amounts received by the Securities Administrator in respect of principal and interest on such Mortgage Certificates paid on the related Distribution Date for the Mortgage Certificates or in connection with a repurchase of any such Mortgage Certificates, but excluding the following:

(a) those portions of each payment of interest on the Mortgage Certificates which represent (i) the Trustee Fee, if any, (ii) the Securities Administrator Fee, if any, and (iii) any other amounts described in the applicable prospectus supplement;

(b) all amounts representing certain expenses reimburseable to the Securities Administrator or the Trustee and other amounts permitted to be withdrawn by the Securities Administrator from the Certificate Account, in each case pursuant to the applicable Trust Agreement; and

(c) reinvestment earnings on payments received in respect of the Mortgage Certificates.

Unscheduled Principal Receipts

The Pooling and Servicing Agreement for a Series backed by Mortgage Loans will specify, as to each type of Unscheduled Principal Receipt, a period (as to each type of Unscheduled Principal Receipt, the "Unscheduled Principal Receipt Period") during which all Unscheduled Principal Receipts of such type received by the Servicer will be distributed to the related Certificateholders on the related Distribution Date. Each Unscheduled Principal Receipt Period will either be (i) the one month period ending on the last day of the calendar month preceding the month in which the applicable Remittance Date occurs (such period a "Prior Month Receipt Period") or (ii) the

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one month period ending on the day preceding the Determination Date preceding the applicable Remittance Date (such period a "Mid-Month Receipt Period").

With respect to certain of the Mortgage Loans serviced by Wells Fargo Bank ("Type 1 Loans"), the Unscheduled Principal Receipt Period with respect to all types of Unscheduled Principal Receipts is a Mid-Month Receipt Period. With respect to certain other Mortgage Loans serviced by Wells Fargo Bank ("Type 2 Loans"), the Unscheduled Principal Receipt Period with respect to all types of Unscheduled Principal Receipts is a Prior Month Receipt Period. With respect to other Servicers, the Unscheduled Principal Receipt Period with respect to partial Unscheduled Principal Receipts is a Prior Month Receipt Period and with respect to Unscheduled Principal Receipts in full is either a Prior Month Receipt Period or a Mid-Month Receipt Period.

Distributions of Interest

With respect to each Series of Certificates, interest on the related Mortgage Loans at the weighted average of the applicable Net Mortgage Interest Rates thereof or interest on the related Mortgage Certificates at the weighted average of the applicable Net Mortgage Certificate Pass-Through Rates thereof, will be passed through monthly to holders of the related Classes of Certificates in the aggregate, in accordance with the particular terms of each such Class of Certificates.

With respect to a Trust Estate containing Mortgage Loans, the "Net Mortgage Interest Rate" for each such Mortgage Loan in a given period will equal the mortgage interest rate for such Mortgage Loan in such period, as specified in the related mortgage note as the same may be amended in accordance with any Servicer Modification (the "Mortgage Interest Rate"), less the portion thereof, if any, not contained in such Trust Estate (the "Fixed Retained Yield"), and less amounts payable to the applicable Servicer for servicing the Mortgage Loan (the "Servicing Fee"), the fee payable to the Master Servicer (the "Master Servicing Fee"), the fee payable to the Trustee (the "Trustee Fee"), if any, and any related expenses or other amounts specified in the applicable prospectus supplement. See "Servicing of the Mortgage Loans--Fixed Retained Yield; Servicing Compensation and Payment of Expenses" for a description of Fixed Retained Yield.

With respect to a Trust Estate containing Mortgage Certificates, the "Net Mortgage Certificate Pass-Through Rate" for each class of Mortgage Certificates will be the pass-through rate for such class (the "Mortgage Certificate Pass-Through Rate") less any expenses and other amounts specified in the related prospectus supplement, which may include but are not limited to, the Trustee Fee and the fee payable to the Securities Administrator (the "Securities Administrator Fee").

Interest will accrue on the principal balance (or notional amount, as described below) of each Class of Certificates entitled to interest at the pass-through rate (the "Pass-Through Rate") for such Class indicated in the applicable prospectus supplement (which may be a fixed rate or an adjustable rate) from the date and for the accrual periods (each, an "Interest Accrual Period") specified in such prospectus supplement. To the extent the Pool Distribution Amount is available therefore, interest accrued during each such specified period on each Class of Certificates entitled to interest (other than a Class of Accrual Certificates) will be distributable on the Distribution Dates specified in the applicable prospectus supplement until the principal balance (or notional amount) of such Class has been reduced to zero. Distributions allocable to interest on each Certificate that is not entitled to distributions allocable to principal will generally be calculated based on the notional amount of such Certificate. The notional amount of a Certificate will not evidence an interest in or entitlement to distributions allocable to principal but will be solely for convenience in expressing the calculation of interest and for certain other purposes.

With respect to any Class of Accrual Certificates, any interest that has accrued but is not paid on a given Distribution Date will be added to the principal balance of such Class of Certificates on that Distribution Date. Distributions of interest on each Class of Accrual Certificates will commence only after the occurrence of the events or the existence of the circumstance specified in such prospectus supplement and, prior to such time, or in the absence of such circumstances, the principal balance of such Class will increase on each Distribution Date by the amount of interest that accrued on such Class during the preceding interest accrual period but that was not required to be distributed to such Class on such Distribution Date. Any such Class of Accrual Certificates will thereafter accrue interest on its outstanding principal balance as so adjusted.

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When mortgagors prepay principal, or when principal is recovered through foreclosure sales or other liquidations of defaulted Mortgage Loans, or when other Unscheduled Principal Receipts occur, a full month's interest for the month of payment or recovery may not be paid or recovered, resulting in interest shortfalls to the extent that such payment or recovery is not included in the distribution to Certificateholders made in the month in which it is received. Interest shortfalls resulting from principal prepayments in full made by mortgagors ("Prepayments in Full") are referred to herein as "Prepayment Interest Shortfalls." The Master Servicer will be obligated, on or before each Distribution Date, to deposit into the Certificate Account for each Series of Certificates backed by Mortgage Loans, from the Master Servicer's own funds (including amounts otherwise payable to the Master Servicer in respect of such Distribution Date as Master Servicing Fees) an amount (such amount, "Compensating Interest") equal to the lesser of (i) the aggregate Prepayment Interest Shortfall with respect to such Distribution Date and (ii) the lesser of (X) the product of (A) 1/12th of 0.20% and (B) the aggregate Scheduled Principal Balance of the Mortgage Loans for such Distribution Date and (Y) the Available Master Servicing Compensation for such Distribution Date.

The "Available Master Servicing Compensation" for any Distribution Date will be equal to the sum of (a) the Master Servicing Fee for such Distribution Date,
(b) interest earned through the business day preceding the applicable Distribution Date on any Prepayments in Full remitted to the Master Servicer and deposited in the Certificate Account (which amount of interest with respect to Prepayments in Full on the Mortgage Loans serviced by Wells Fargo Bank is expected to be zero unless the Remittance Date for such Mortgage Loans changes as described below under "Servicing of the Mortgage Loans--Changes in Servicing") and (c) the aggregate amount of Month End Interest remitted by the Servicers to the Master Servicer pursuant to the related Underlying Servicing Agreements.

The actual amount of the Available Master Servicing Compensation is subject to a number of variables and depends, in part, on the provisions of the Underlying Servicing Agreements of the Servicers of the Mortgage Loans. For example, Wells Fargo Bank, as a Servicer, is not currently required to remit funds to the Master Servicer until the business day preceding the applicable Distribution Date. Therefore with respect to any loans serviced by Wells Fargo Bank the amount of Available Master Servicing Compensation determined under clause (b) would be zero.

The calculation of Month End Interest also varies depending on the provisions of the Underlying Servicing Agreements. With respect to the Mortgage Loans serviced by Wells Fargo Bank, "Month End Interest" for each Distribution Date will be equal to the lesser of (i) the aggregate Prepayment Interest Shortfalls with respect to the Mortgage Loans serviced by Wells Fargo Bank and (ii) the product of 1/12th of 0.20% and the aggregate scheduled principal balance (as determined in the applicable Underlying Servicing Agreement) of the Mortgage Loans serviced by Wells Fargo Bank. With respect to the Mortgage Loans serviced by each Other Servicer, Month End Interest for each Distribution Date depends in part on whether such Other Servicer has agreed to remit Prepayments in Full to the Master Servicer daily on a specified business day following receipt rather than waiting until the Remittance Date. Although an Underlying Servicing agreement may provide an exception, "Month End Interest" for Other Servicers will generally equal the lesser of (a) (i) with respect to Other Servicers remitting Prepayments in Full on a daily basis, the aggregate Curtailment Interest Shortfalls with respect to the Mortgage Loans serviced by such Other Servicer or (ii) with respect to Other Servicers not remitting Prepayments in Full on a daily basis, the sum of the aggregate Prepayment Interest Shortfalls and aggregate Curtailment Interest Shortfalls with respect to the Mortgage Loans serviced by such Other Servicer and (b) the sum of (X) for each Mortgage Loan serviced by such Other Servicer, the product of 1/12th of the applicable Servicing Fee Rate and the scheduled principal balance (as determined in the applicable Underlying Servicing Agreement) of such Mortgage Loan serviced by such Other Servicer and (Y) with certain exceptions, reinvestment earnings on payments received in respect of the Mortgage Loans or on other amounts on deposit in the related Servicer Custodial Account pursuant to the related Underlying Servicing Agreement on such Distribution Date. As described herein under "Servicing of the Mortgage Loans -- Changes in Servicing," a Servicer not currently remitting Prepayments in Full on a daily basis may agree to begin to do so at some time in the future. In conjunction therewith, the amount of Month End Interest such Servicer is required to remit may be decreased or such Servicer may be relieved of its obligation to remit any Month End Interest. If an Other Servicer that is not currently remitting Prepayments in Full on a daily basis begins to do so, any such change may have an impact on the amount of Compensating Interest by increasing the amount described in clause (b) of the definition of Available Master Servicing Compensation and decreasing the amount described in clause (c) of the definition thereof. No assurance can be given as to the timing of any such changes or that any such changes will occur.

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Any interest shortfalls arising from Unscheduled Principal Receipts in full that are not Prepayments in Full and any interest shortfalls resulting from the timing of the receipt of partial principal prepayments ("Curtailments") by mortgagors ("Curtailment Interest Shortfalls") or of other partial Unscheduled Principal Receipts with respect to the Mortgage Loans will not be offset by Compensating Interest.

Distributions of Principal

The principal balance of any Class of Certificates entitled to distributions of principal will generally be the original principal balance of such Class specified in such prospectus supplement, reduced by all distributions reported to the holders of such Certificates as allocable to principal and any losses on the related Mortgage Assets allocated to such Class of Certificates and (i) in the case of Accrual Certificates, increased by all interest accrued but not then distributable on such Accrual Certificates and (ii) in the case of a Series of Certificates representing interests in a Trust Estate containing adjustable rate Mortgage Loans, increased by any Deferred Interest allocable to such Class. The principal balance of a Class of Certificates generally represents the maximum specified dollar amount (exclusive of any interest that may accrue on such Class to which the holder thereof is entitled from the cash flow on the related Mortgage Assets at such time) and will decline to the extent of distributions in reduction of the principal balance of, and allocations of losses to such Class. Certificates with no principal balance will not receive distributions in respect of principal. The applicable prospectus supplement will specify the method by which the amount of principal to be distributed on the Certificates on each Distribution Date will be calculated and the manner in which such amount will be allocated among the Classes of Certificates entitled to distributions of principal.

Categories of Classes of Certificates

The Certificates of any Series may be comprised of one or more Classes. Such Classes, in general, fall into different categories. Certain of the more typical categories are defined below. The prospectus supplement for a Series of Certificates may identify the Classes which comprise such Series by reference to the following categories or another category specified in the applicable prospectus supplement. With respect to as Trust Estate containing Mortgage Certificates, one or more classes of such Mortgage Certificates may be identified as falling into one or more of the categories described below.

Principal Types

"Accretion Directed Certificates" are Certificates that receive principal payments from amounts that would otherwise be distributed as interest on specified Accrual Certificates. Such principal payments may be in lieu of or in addition to principal payments from principal receipts on the Mortgage Assets for the related Series.

"Companion Certificates" (also sometimes referred to as "Support Certificates") are Certificates that are entitled to receive principal payments on any Distribution Date only if scheduled payments have been made on specified Planned Amortization Certificates, Targeted Amortization Certificates and/or Scheduled Amortization Certificates.

"Component Certificates" are Certificates consisting of two or more specified components (each, a "Component") as described in the applicable prospectus supplement. The Components of a Class of Component Certificates may have different principal and/or interest payment characteristics but together constitute a single class and do not represent severable interests. Each Component of a Class of Component Certificates may be identified as falling into one or more of the categories described herein.

"Lockout Certificates" are Senior Certificates that are designed not to participate in, or to participate to a limited extent in (i.e., to be "locked out" of), for a specified period, the receipt of (1) principal prepayments on the Mortgage Assets that are allocated disproportionately to the Classes of Senior Certificates of such Series as a group pursuant to a "shifting interest" structure and/or (2) scheduled principal payments on the Mortgage Assets that are allocated to the Senior Certificates as a group. A Class of Lockout Certificates will typically not be entitled to receive, or will be entitled to receive only a restricted portion of, distributions of principal prepayments and/or scheduled principal payments, as applicable, for a period of several years, during which time all or a portion of such principal payments that it would otherwise be entitled to receive in the absence of a "lockout" structure will be distributed in reduction of the principal balances of other Senior Certificates. Lockout Certificates are designed to minimize weighted average life volatility during the lockout period.

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"Notional Amount Certificates" are Certificates having no principal balance and bearing interest on the related notional amount. The notional amount is a hypothetical amount used for calculating interest distributions.

"Pass-Through Certificates" are Senior Certificates that are entitled to receive a specified percentage of the principal payments that are distributable to the Senior Certificates or applicable group of Senior Certificates (other than any Ratio Strip Class) in the aggregate on each Distribution Date until the principal balances of all the Senior Certificates or applicable group of Senior Certificates are reduced to zero and that is not designated as a Class of Sequential Pay Certificates.

"Planned Amortization Certificates" (also sometimes referred to as "PAC Certificates") are Certificates that are designed to receive principal payments using a predetermined principal balance schedule derived by assuming two constant prepayment rates for the underlying Mortgage Assets. These two rates are the endpoints for the "structuring range" for a Class of Planned Amortization Certificates. The Planned Amortization Certificates in any Series may be subdivided into different categories (e.g., Planned Amortization Certificates I ("PAC I") Planned Amortization Certificates II ("PAC II") and so forth) derived using different structuring ranges and/or payment priorities. A Class of PAC Certificates is designed to provide protection against volatility of weighted average life if prepayments occur at a constant rate within the structuring range.

"Ratio Strip Certificates" are Certificates that are entitled to receive a constant proportion, or "ratio strip," of the principal payments on the underlying Mortgage Assets.

"Scheduled Amortization Certificates" (also sometimes referred to as "Scheduled Certificates") are Certificates that are designed to receive principal payments using a predetermined principal balance schedule but are not designated as Planned Amortization Certificates or Targeted Amortization Certificates. The schedule is derived by assuming either two constant prepayment rates or a single constant prepayment rate for the underlying Mortgage Loans. In the former case, the two rates are the endpoints for the "structuring range" for the Scheduled Amortization Certificates and such range generally is narrower than that for a Class of Planned Amortization Certificates. Typically, the Support Certificates for the applicable Series of Certificates generally will represent a smaller percentage of the Class of Scheduled Amortization Certificates than Support Certificates generally would represent in relation to a Class of Planned Amortization Certificates or Targeted Amortization Certificates. A Class of Scheduled Amortization Certificates is generally less sensitive to weighted average life volatility as a result of prepayments than a Class of Support Certificates but more sensitive than a Class of Planned Amortization Certificates or Targeted Amortization Certificates.

"Senior Certificates" are Certificates that are entitled to receive payments of principal and interest on each Distribution Date prior to the Classes of Subordinated Certificates.

"Sequential Pay Certificates" are Certificates that are entitled to receive principal payments in a prescribed sequence, that do not have a predetermined principal balance schedule and that, in most cases, are entitled to receive payments of principal continuously from the first Distribution Date on which it receives principal until they are retired. A Class of Sequential Pay Certificates may receive principal payments concurrently with one or more other Classes of Sequential Pay Classes. A single Class that is entitled to receive principal payments before or after other Classes in the same Series of Certificates may be identified as a Class of Sequential Pay Certificates.

"Subordinated Certificates" are Certificates that are entitled to receive payments of principal and interest on each Distribution Date only after the Senior Certificates and Classes of Subordinated Certificates with higher priority of distributions, if any, have received their full principal and interest entitlements.

"Super Senior Certificates" are Senior Certificates that will not bear their share of certain losses after the Classes of Subordinated Certificates are no longer outstanding for so long as one or more other specified Classes of Senior Certificates are outstanding.

"Super Senior Support Certificates" are Senior Certificates that bear certain losses allocated to one or more Classes of Super Senior Certificates after the Classes of Subordinated Certificates are no longer outstanding.

"Targeted Amortization Certificates" (also sometimes referred to as "TAC Certificates") are Certificates that are designed to receive principal payments using a predetermined principal balance schedule derived by

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assuming a single constant prepayment rate for the underlying Mortgage Assets. A Class of TAC Certificates is designed to provide some protection against shortening of weighted average life if prepayments occur at a rate exceeding the assumed constant prepayment rate used to derive the principal balances schedule of such Class of Certificates.

Interest Types

"Accrual Certificates" are Certificates that accrete the amount of accrued interest otherwise distributable on such Certificates, which amount will be added as principal to the principal balance of such Certificates on each applicable Distribution Date. Such accretion may continue until some specified event has occurred or until such Accrual Certificates are retired.

"Fixed Rate Certificates" are Certificates with an interest rate that is fixed throughout the life of the Class.

"Floating Rate Certificates" are Certificates with an interest rate that resets periodically based upon a designated index and that varies directly with changes in such index.

"Interest Only Certificates" are Certificates that are entitled to receive some or all of the interest payments made on the Mortgage Assets and little or no principal. Interest Only Certificates have either a nominal principal balance or a notional amount. A nominal principal balance represents actual principal that will be paid on the Certificates. It is referred to as nominal since it is extremely small compared to other Classes. A notional amount is the amount used as a reference to calculate the amount of interest due on a Class of Interest Only Certificates that is not entitled to any distributions in respect of principal.

"Inverse Floating Rate Certificates" are Certificates with an interest rate that resets periodically based upon a designated index and that varies inversely with changes in such index and with changes in the interest rate payable on the related Class of Floating Rate Certificates.

"Principal Only Certificates" are Certificates that do not bear interest and are entitled to receive only distributions in respect of principal.

"Step Coupon Certificates" are Certificates with a fixed interest rate that is reduced or increased to a different fixed rate after a specified period of time. The difference between the initial interest rate and the subsequent interest rate may be supported by a reserve fund established on the Closing Date.

"Variable Rate Certificates" are Certificates with an interest rate that resets periodically and is calculated by reference to the rate or rates of interest applicable to the Mortgage Assets.

Pass-Through Rates Based on LIBOR

General

The index used to determine the Pass-Through Rates for Floating Rate and Inverse Floating-Rate Certificates will be set forth in the applicable prospectus supplement. The index used may be the London interbank offered rate quotation for one-month U.S. dollar deposits ("LIBOR").

The Pass-Through Rates based on LIBOR for an Interest Accrual Period for Floating Rate and Inverse Floating Rate Certificates after the initial Interest Accrual Period will be determined on the second LIBOR Business Day preceding the commencement of each Interest Accrual Period (each, a "Rate Determination Date"). A "LIBOR Business Day" is a day on which banks are open for dealing in foreign currency and exchange in London, England and the City of New York.

Determination of LIBOR

On each Rate Determination Date, the Paying Agent will determine LIBOR for the succeeding Interest Accrual Period for the Floating Rate and Inverse Floating Rate Certificates of a Series. LIBOR will equal the interbank offered rate for one-month deposits in U.S. dollars as found on Page LIBOR01 as of 11:00
A.M. London time on

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such Rate Determination Date. As used therein, "Page LIBOR01" means the display designated as Reuters Screen LIBOR01 Page or such other page as may replace Reuters Screen LIBOR01 Page on that service for the purpose of displaying London interbank offered rates of major banks.

If on any Rate Determination Date the Paying Agent is unable to determine LIBOR on the basis of the method set forth in the preceding paragraph. LIBOR for the next Interest Accrual Period will be the higher of (x) LIBOR as determined on the previous Rate Determination Date or (y) the Reserve Interest Rate. The "Reserve Interest Rate" will be the rate per annum which the Paying Agent determines to be either (A) the arithmetic mean (rounding such arithmetic mean upwards if necessary to the nearest whole multiple of 1/16%) of the one-month U.S. dollar lending rate that the banks set forth in the applicable Agreement are quoting on the relevant Rate Determination Date, to the principal London offices of at least two leading banks in the London interbank market or (B) in the event that the Paying Agent can determine no such arithmetic mean, the lowest one-month U.S. lending rate that the banks set forth in the applicable Agreement are quoting on such Rate Determination Date to leading European banks.

If on any Rate Determination Date the Paying Agent is required but is unable to determine the Reserve Interest Rate in the manner provided in the preceding paragraph, LIBOR for the next Interest Accrual Period will be LIBOR as determined on the previous Rate Determination Date, or in the case of the first Rate Determination Date, the rate specified in the applicable Agreement.

The establishment of LIBOR by the Paying Agent and the Paying Agent's subsequent calculation of the Pass-Through Rates applicable to the Floating Rate and Inverse Floating Rate Certificates for the relevant Interest Accrual Period, in the absence of manifest error, will be final and binding.

Subordination

If so provided in the applicable prospectus supplement, one or more Classes of Senior Certificates will be entitled to receive all or a disproportionate percentage of the payments of principal that are received from borrowers in advance of their scheduled due dates and are not accompanied by amounts representing scheduled interest due after the months of such payments or of other unscheduled principal receipts or recoveries in the percentages and under the circumstances or for the periods specified in such prospectus supplement. Any such allocation of principal prepayments or other unscheduled receipts or recoveries in respect of principal to such Class or Classes of Senior Certificates will have the effect of accelerating the amortization of such Senior Certificates while increasing the interests evidenced by the Subordinated Certificates in the Trust Estate. Increasing the interests of the Subordinated Certificates relative to that of the Senior Certificates is intended to preserve the availability of the subordination provided by the Subordinated Certificates.

To the extent described in the related prospectus supplement, any Mortgage Certificates contained in a Trust Estate may be Senior Certificates which benefit from credit enhancement provided by the subordination of Subordinated Certificates of the same Series, or such Mortgage Certificates may be Subordinated Certificates, thereby providing subordination to other Certificates of the same Series.

If specified in the applicable prospectus supplement, the rights of the holders of the Subordinated Certificates of a Series of Certificates for which credit enhancement is provided through subordination to receive distributions with respect to the Mortgage Assets in the related Trust Estate will be subordinated to such rights of the holders of the Senior Certificates of the same Series. This subordination is intended to enhance the likelihood of regular receipt by holders of Senior Certificates of the full amount of scheduled monthly payments of principal and interest due them and to provide limited protection to the holders of the Senior Certificates against losses due to mortgagor defaults on the Mortgage Loans or Underlying Loans, as applicable.

The protection afforded to the holders of Senior Certificates of a Series of Certificates for which credit enhancement is provided through subordination by the subordination feature described above will be effected by (i) the preferential right of such holders to receive, prior to any distribution being made in respect of the related Subordinated Certificates on each Distribution Date, current distributions on the related Mortgage Assets of principal and interest due them on each Distribution Date out of the funds available for distribution on such date in the Certificate Account, (ii) by the right of such holders to receive future distributions on the Mortgage Assets that would otherwise have been payable to the holders of Subordinated Certificates and/or
(iii) by the prior allocation to the Subordinated Certificates of all or a portion of losses realized on the related Mortgage Assets.

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Realized Losses on Liquidated Loans (other than Excess Special Hazard Losses, Excess Fraud Losses and Excess Bankruptcy Losses as described below) will be allocated to the holders of Subordinated Certificates through a reduction of the amount of principal payments on the Mortgage Loans to which such holders are entitled before any corresponding reduction is made in respect of the Senior Certificates.

A "Realized Loss" is any Liquidated Loan Loss (including any Special Hazard Loss and any Fraud Loss) or any Bankruptcy Loss or the amount of any reduction in principal due or interest forgiven on a Mortgage Loan as a result of a Servicer Modification. A "Liquidated Loan" is a defaulted Mortgage Loan as to which the Servicer has determined that all recoverable liquidation and insurance proceeds have been received. However, a loan will be considered a Liquidated Loan if a PMI Advance has been made. See "Servicing of the Mortgage Loans--PMI Advances." A "Liquidated Loan Loss" on a Liquidated Loan for any Distribution Date is equal to the excess, if any, of (i) the unpaid principal balance of such Liquidated Loan, plus accrued interest thereon at the Mortgage Interest Rate through the last day of the month preceding the month in which such Distribution Date occurs, over (ii) net Liquidation Proceeds. For purposes of calculating the amount of any Liquidated Loan Loss, all net Liquidation Proceeds (after reimbursement of any previously unreimbursed Periodic Advance) will be applied first to accrued interest and then to the unpaid principal balance of the Liquidated Loan. A "Special Hazard Loss" is (A) a Liquidated Loan Loss suffered by a Mortgaged Property on account of direct physical loss exclusive of (i) any loss covered by a standard hazard insurance policy or, if the Mortgaged Property is located in an area identified in the Federal Register by the Federal Emergency Management Agency as having special flood hazards, a flood insurance policy, of the types described under "Servicing of the Mortgage Loans--Insurance Policies" and (ii) any loss caused by or resulting from (a) normal wear and tear, (b) dishonest acts of the Trustee, the Master Servicer or the Servicer or
(c) errors in design, faulty workmanship or faulty materials, unless the collapse of the property or a part thereof ensues or (B) a Liquidated Loan Loss arising from or related to the presence or suspected presence of hazardous wastes or substances on a Mortgaged Property. A "Fraud Loss" is a Liquidated Loan Loss incurred on a Liquidated Loan as to which there was fraud in the origination of such Mortgage Loan. A "Bankruptcy Loss" is a loss attributable to certain actions which may be taken by a bankruptcy court in connection with a Mortgage Loan, including a reduction by a bankruptcy court of the principal balance of or the interest rate on a Mortgage Loan or an extension of its maturity. A "Debt Service Reduction" means a reduction in the amount of monthly payments due to certain bankruptcy proceedings, but does not include any permanent forgiveness of principal. A "Deficient Valuation" with respect to a Mortgage Loan means a valuation by a court of the Mortgaged Property in an amount less than the outstanding indebtedness under the Mortgage Loan or any reduction in the amount of monthly payments that results in a permanent forgiveness of principal, which valuation or reduction results from a bankruptcy proceeding. Special Hazard Losses in excess of the amount, if any, specified in the applicable prospectus supplement (the "Special Hazard Loss Amount") are "Excess Special Hazard Losses." Fraud Losses in excess of the amount, if any, specified in the applicable prospectus supplement (the "Fraud Loss Amount") are "Excess Fraud Losses." Bankruptcy losses in excess of the amount, if any, specified in the applicable prospectus supplement (the "Bankruptcy Loss Amount") are "Excess Bankruptcy Losses." If and to the extent specified in the applicable prospectus supplement, Excess Special Hazard Losses, Excess Fraud Losses or Excess Bankruptcy Losses with respect to a Series backed by Mortgage Loans will be allocated on a pro rata basis among the related Classes of Senior and Subordinated Certificates. An allocation of a loss on a "pro rata basis" among two or more Classes of Certificates means an allocation on a pro rata basis to each such Class of Certificates on the basis of their then-outstanding principal balances in the case of the principal portion of a loss or based on the accrued interest thereon in the case of an interest portion of a loss.

For any Series of Certificates backed by Mortgage Loans where the amounts of the Special Hazard Loss Amount, Fraud Loss Amount and Bankruptcy Loss Amount for such Series of Certificates are each expected to be less than the amount of principal payments on the Mortgage Loans to which the holders of the Subordinated Certificates of such Series are initially entitled (such amount being subject to reduction, as described above, as a result of allocation of losses on liquidated Mortgage Loans that are not Special Hazard Losses, Fraud Losses or Bankruptcy Losses), the holders of Subordinated Certificates of such Series will bear the risk of Special Hazard Losses, Fraud Losses and Bankruptcy Losses to a lesser extent than they will bear other losses on Liquidated Loans.

Although the subordination feature described above is intended to enhance the likelihood of timely payment of principal and interest to the holders of Senior Certificates, shortfalls could result in certain circumstances. For example, a shortfall in the payment of principal otherwise due the holders of Senior Certificates could occur if losses

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realized on the Mortgage Assets in a Trust Estate were exceptionally high and were concentrated in a particular month.

The holders of Subordinated Certificates will not be required to refund any amounts previously properly distributed to them, regardless of whether there are sufficient funds on a subsequent Distribution Date to make a full distribution to holders of each Class of Senior Certificates of such Series.

Other Credit Enhancement

General

In addition to, or in substitution for, the subordination discussed above under "Description of the Certificates--Subordination", credit enhancement may be provided with respect to any Series of Certificates in one or more of the methods described below. The applicable prospectus supplement will describe the material terms of such credit enhancement, including any limits on the timing or amount of such credit enhancement or any conditions that must be met before such credit enhancement may be accessed. If the provider of the credit enhancement is liable or contingently liable to provide payments representing 10% or more of the cash flow supporting any offered Class of Certificates, the applicable prospectus supplement will disclose the name of the provider, the organizational form of the provider, the general character of the business of the provider and the financial information required by Item 1114(b)(2) of Regulation AB (17 C.F.R. 229.1114). Copies of the limited guarantee, financial guaranty insurance policy, surety bond, letter of credit, pool insurance policy, mortgagor bankruptcy bond, special hazard insurance policy or Cash Flow Agreement, if any, relating to a Series of Certificates will be filed with the SEC as an exhibit to a Current Report on Form 8-K.

Limited Guarantee

If specified in the prospectus supplement with respect to a Series of Certificates, credit enhancement may be provided in the form of a limited guarantee issued by a guarantor named in such prospectus supplement. The limited guarantee may cover deficiencies in amounts otherwise payable on some or all of the Certificates of a Series. The limited guarantee may cover timely distributions of interest or full distributions of principal or both on the basis of a schedule of principal distributions set forth in or determined in the manner specified in the applicable prospectus supplement. The limited guarantee may provide additional protection against losses on the Mortgage Assets included in a Trust Estate, provide payment of administrative expenses, or establish a minimum reinvestment rate on the payments made on the Mortgage Assets or principal payment rate on the Mortgage Assets. A limited guarantee will be limited in amount to the dollar amount or percentage of the principal balance of the Mortgage Assets or Certificates specified in the applicable prospectus supplement.

Financial Guaranty Insurance Policy or Surety Bond

If specified in the prospectus supplement with respect to a Series of Certificates, credit enhancement may be provided in the form of a financial guaranty insurance policy or a surety bond issued by one or more insurers named in such prospectus supplement. The financial guaranty insurance policy will guarantee, with respect to one or more Classes of Certificates of the related Series, timely distributions of interest and ultimate distributions of principal at the dates set forth in or determined in the manner specified in the prospectus supplement. If specified in the prospectus supplement, the financial guaranty insurance policy will also guarantee against any payment made to a Certificateholder that is subsequently recovered as a preferential transfer under the Bankruptcy Code.

Letter of Credit

If specified in the prospectus supplement for a Series of Certificates, credit enhancement may be provided by a letter of credit issued by a bank or other financial institution specified in the applicable prospectus supplement. Under the letter of credit, the provider will be obligated to pay up to an aggregate fixed dollar amount, net of previous drawings on the letter, equal to the percentage specified in the prospectus supplement of the unpaid principal balance of the Mortgage Assets or of one or more Classes of Certificates. If specified in the prospectus supplement, the letter of credit may permit drawings in the event of losses not covered by insurance policies or other credit support, such as losses arising from damage not covered by standard hazard insurance policies, losses

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resulting from the bankruptcy of a borrower and the application of certain provisions of the Bankruptcy Code, or losses resulting from denial of insurance coverage due to misrepresentations in connection with the origination of a Mortgage Loan. The amount available under the letter of credit will, in all cases, be reduced to the extent of the unreimbursed payments previously paid. The obligations of the provider under the letter of credit for each Series of Certificates will expire at the earlier of the date specified in the prospectus supplement or the termination of the Trust.

Pool Insurance Policy

If specified in the prospectus supplement relating to a Series of Certificates backed by Mortgage Loans, credit enhancement may be provided by a mortgage pool insurance policy for the Mortgage Loans in the related Trust Estate. Each mortgage pool insurance policy, in accordance with the limitations described in this prospectus and in the prospectus supplement, if any, will cover any loss by reason of default on a Mortgage Loan in an amount equal to a percentage specified in the applicable prospectus supplement of the unpaid principal balance of the Mortgage Loans. As described under "Servicing of the Mortgage Loans--Enforcement of "Due-on-Sale" Clauses; Realization Upon Defaulted Mortgage Loans," the Servicer or the Master Servicer, as the case may be, generally will be required to use its best efforts to maintain the mortgage pool insurance policy and to present claims to the pool insurer. The mortgage pool insurance policies, however, are not blanket policies against loss, since claims may only be made respecting particular defaulted Mortgage Loans and only upon satisfaction of specified conditions precedent described below. The mortgage pool insurance policies will generally not cover losses due to a failure to pay or denial of a claim under a primary mortgage insurance policy, regardless of the reason for nonpayment.

As more specifically provided in the applicable prospectus supplement, each mortgage pool insurance policy will provide for conditions under which claims may be presented and covered under the policy. Upon satisfaction of these conditions, the pool insurer will have the option either (a) to purchase the property securing the defaulted Mortgage Loan at a price equal to its unpaid principal balance plus accrued and unpaid interest at the applicable Mortgage Interest Rate to the date of purchase plus certain Advances, or (b) to pay the amount by which the sum of the unpaid principal balance of the defaulted Mortgage Loan plus accrued and unpaid interest at the Mortgage Interest Rate to the date of payment of the claim plus certain Advances exceeds the proceeds received from an approved sale of the Mortgaged Property, in either case net of certain amounts paid or assumed to have been paid under any related primary mortgage insurance policy.

Certificateholders may experience a shortfall in the amount of interest payable on the related Certificates in connection with the payment of claims under a mortgage pool insurance policy because the pool insurer is only required to remit unpaid interest through the date a claim is paid rather than through the end of the month in which the claim is paid. In addition, Certificateholders may also experience losses with respect to the related Certificates in connection with payments made under a mortgage pool insurance policy to the extent that the related Servicer expends funds to cover unpaid real estate taxes or to repair the related Mortgaged Property in order to make a claim under a mortgage pool insurance policy, as those amounts will not be covered by payments under the policy and will be reimbursable to the related Servicer from funds otherwise payable to the Certificateholders. If any Mortgaged Property securing a defaulted Mortgage Loan is damaged and proceeds, if any from the related hazard insurance policy or applicable special hazard insurance policy are insufficient to restore the damaged property to a condition sufficient to permit recovery under the mortgage pool insurance policy, a Servicer will generally not be required to expend its own funds to restore the damaged property unless it determines that (a) restoration will increase the proceeds to one or more Classes of Certificates on liquidation of the Mortgage Loan after reimbursement of the related Servicer for its expenses and (b) the expenses will be recoverable by it through Liquidation Proceeds or insurance proceeds.

A mortgage pool insurance policy and some primary mortgage insurance policies will generally not insure against loss sustained by reason of a default arising from, among other things, fraud or negligence in the origination or servicing of a Mortgage Loan, including misrepresentation by the mortgagor, the seller or other persons involved in the origination of the Mortgage Loan, failure to construct a mortgaged property in accordance with plans and specifications or bankruptcy, unless as specified in the applicable prospectus supplement, an endorsement to the mortgage pool insurance policy provides for insurance against that type of loss.

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The original amount of coverage under each mortgage pool insurance policy will be reduced over the life of the related Series of Certificates by the aggregate amount of claims paid less the aggregate of the net amounts realized by the pool insurer upon disposition of all foreclosed properties. The amount of claims paid includes some expenses incurred by the related Servicer or Master Servicer as well as accrued interest on delinquent Mortgage Loans to the date of payment of the claim. Accordingly, if aggregate net claims paid under any mortgage pool insurance policy reach the original policy limit, coverage under that mortgage pool insurance policy will be exhausted and any further losses will be borne by the related Certificates, to the extent not covered by other credit enhancements.

Special Hazard Insurance Policy

If specified in the prospectus supplement relating to a Series of Certificates backed by Mortgage Loans, credit enhancement may be provided by a special hazard insurance policy. Any insurance policy covering Special Hazard Losses obtained for a Trust will be issued by the insurer named in the applicable prospectus supplement. Each special hazard insurance policy will be subject to limitations described in this paragraph and in the applicable prospectus supplement, if any, and will protect the related Certificateholders from Special Hazard Losses. Aggregate claims under a special hazard insurance policy will be limited to the amount set forth in the related Pooling and Servicing Agreement and will be subject to reduction as described in the related Pooling and Servicing Agreement. A special hazard insurance policy will provide that no claim may be paid unless hazard and, if applicable, flood insurance on the Mortgaged Property securing the Mortgage Loan has been kept in force and other protection and preservation expenses have been paid by the related Servicer or Master Servicer, as the case may be.

In accordance with the foregoing limitations, a special hazard insurance policy will provide that, where there has been damage to the Mortgaged Property securing a foreclosed Mortgage Loan, title to which has been acquired by the insured, and to the extent the damage is not covered by the hazard insurance policy or flood insurance policy, if any, maintained by the mortgagor or the related Servicer or Master Servicer, as the case may be, the insurer will pay the lesser of (i) the cost of repair or replacement of the related Mortgaged Property or (ii) upon transfer of the property to the insurer, the unpaid principal balance of the Mortgage Loan at the time of acquisition of the related property by foreclosure or deed in lieu of foreclosure, plus accrued interest at the Mortgage Interest Rate to the date of claim settlement and certain expenses incurred by the related Servicer or Master Servicer, as the case may be, with respect to the related Mortgaged Property.

If the Mortgaged Property is transferred to a third party in a sale approved by the special hazard insurer, the amount that the special hazard insurer will pay will be the amount under (ii) above reduced by the net proceeds of the sale of the Mortgaged Property. If the unpaid principal balance plus accrued interest and certain Advances is paid by the special hazard insurer, the amount of further coverage under the related special hazard insurance policy will be reduced by that amount less any net proceeds from the sale of the Mortgaged Property. Any amount paid as the cost of repair of the property will further reduce coverage by that amount. Restoration of the property with the proceeds described under (i) above will satisfy the condition under any mortgage pool insurance policy that the property be restored before a claim under the policy may be validly presented with respect to the defaulted Mortgage Loan secured by the related Mortgaged Property. The payment described under (ii) above will render presentation of a claim relating to a Mortgage Loan under the related mortgage pool insurance policy unnecessary. Therefore, so long as a mortgage pool insurance policy remains in effect, the payment by the insurer under a special hazard insurance policy of the cost of repair or of the unpaid principal balance of the related Mortgage Loan plus accrued interest and certain Advances will not affect the total insurance proceeds paid to Certificateholders, but will affect the relative amounts of coverage remaining under the related special hazard insurance policy and mortgage pool insurance policy.

Mortgagor Bankruptcy Bond

If specified in the prospectus supplement relating to a Series of Certificates backed by Mortgage Loans, a bankruptcy bond to cover losses resulting from proceedings under the federal Bankruptcy Code with respect to a Mortgage Loan will be issued by an insurer named in the applicable prospectus supplement. Each bankruptcy bond will cover, to the extent specified in the applicable prospectus supplement, certain losses resulting from a reduction by a bankruptcy court of scheduled payments of principal and interest on a Mortgage Loan or a reduction by the court of the unpaid principal balance of a Mortgage Loan and will cover certain unpaid interest on the amount of a

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principal reduction from the date of the filing of a bankruptcy petition. The required amount of coverage under each bankruptcy bond will be set forth in the applicable prospectus supplement.

Reserve Fund

If specified in the applicable prospectus supplement, credit enhancement with respect to a Series of Certificates may be provided by the establishment of one or more reserve funds for the Series. Any reserve fund for a Series may be funded (i) by a deposit of cash, U.S. Treasury securities or instruments evidencing entitlements to principal or interest payments, letters of credit, demand notes, certificates of deposit or a combination thereof in the aggregate amount specified in the applicable prospectus supplement or (ii) by the deposit from time to time of certain amounts received on or in respect of the related Mortgage Assets, as specified in the applicable prospectus supplement.

Reserve funds may be established to provide limited protection, in an amount satisfactory to each Rating Agency, against certain interest shortfalls arising from the timing of principal prepayments, certain types of losses not covered by insurance policies or other credit support, such as losses arising from damage not covered by standard hazard insurance policies, losses resulting from the bankruptcy of a borrower and the application of certain provisions of the Bankruptcy Code or losses resulting from denial of insurance coverage due to fraud or misrepresentation in connection with the origination of a Mortgage Asset. Following each Distribution Date amounts in a reserve fund in excess of any required reserve fund amount may be released from the reserve fund under the conditions and to the extent specified in the prospectus supplement and will not be available for further application to the related Certificates.

If specified in the prospectus supplement, any reinvestment income or other gain from investments in Eligible Investments will be credited to the related reserve fund for the Series, and any loss resulting from the investments will be charged to the reserve fund. The reserve fund for a Series will not be a part of the Trust Estate.

Cross Collateralization

If specified in the applicable prospectus supplement, the beneficial ownership of separate groups of Mortgage Assets included in a Trust Estate may be evidenced by separate Classes of Certificates. In this case, credit support may be provided by a cross collateralization feature which requires that distributions be made to certain Classes from Mortgage Assets payments that would otherwise be distributed to Subordinated Certificates evidencing a beneficial ownership interest in other asset groups within the same Trust Estate. As a result, the amount of credit enhancement available to a Class of Certificates against future losses on the Mortgage Assets in which that Class represents an interest may be reduced as the result of losses on a group of Mortgage Assets in which that Class has no interest. The applicable prospectus supplement for a Series that includes a cross collateralization feature will describe its specific operation.

Overcollateralization

If specified in the applicable prospectus supplement, subordination provisions of a Series may be used to accelerate to a limited extent the amortization of one or more Classes of Certificates relative to the amortization of the related Mortgage Assets. The accelerated amortization is achieved by the application of certain excess interest to the payment of principal of one or more Classes of Certificates. This acceleration feature creates, with respect to the Mortgage Assets or a group of Mortgage Assets, overcollateralization which results from the excess of the aggregate principal balance of the related Mortgage Assets, or group of Mortgage Assets, over the principal balance of the related Class or Classes of Certificates. This acceleration may continue for the life of the related Certificates, or may have a shorter duration. Once the required level of overcollateralization is reached, and subject to certain provisions specified in the applicable prospectus supplement, this limited acceleration feature may cease or the acceleration may decrease, unless necessary to maintain the required level of overcollateralization.

In addition to overcollateralization which is built up during the life of the related Series as discussed in the preceding paragraph, if specified in the applicable prospectus supplement, a Series may contain overcollateralization at the initial issuance of the Certificates of such Series. Subject to certain provisions specified in the applicable prospectus supplement, the level of overcollateralization at initial issuance may increase, decrease or remain constant for the life of the related Certificates.

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Excess Interest

If specified in the applicable prospectus supplement, the Mortgage Assets in a Trust may generate more interest than is necessary to pay the interest earned on the Classes of Certificates each month. The excess interest may be used to maintain overcollateralization, to pay interest that was previously earned but not paid to certain Classes of Certificates and to reimburse certain Classes of Certificates for losses and certain shortfalls that they experienced previously.

If specified in the applicable prospectus supplement, amounts received by the Trustee (or other party specified in the applicable prospectus supplement) under any Cash Flow Agreement as described above under "The Trust Estates-Cash Flow Agreements" may also be used to provide credit enhancement for one or more Classes of Certificates.

Exchangeable Certificates

General

If specified in a prospectus supplement for a Series, certain Classes of Certificates may be Exchangeable REMIC Certificates or Exchangeable Certificates. "Exchangeable REMIC Certificates" are Certificates that may be exchanged in whole or in part, upon notice and the payment to the Master Servicer of an exchange fee, for proportionate interests in one or more specified Classes of Exchangeable Certificates in the same Series, as described in the applicable prospectus supplement. "Exchangeable Certificates" are Certificates that may be exchanged in whole or in part, upon notice and the payment to the Master Servicer of an exchange fee, for proportionate interests in one or more specified Classes of Exchangeable REMIC Certificates in the same Series, as described in the applicable prospectus supplement.

If a Series includes Exchangeable REMIC Certificates and Exchangeable Certificates, all of these Classes of Exchangeable REMIC Certificates and Exchangeable Certificates will be listed in the applicable prospectus supplement. At any time after their initial issuance, any Class of Exchangeable REMIC Certificates or multiple Classes of Exchangeable REMIC Certificates (such multiple Classes referred to as a "REMIC Combination") may be exchanged for the related Class of Exchangeable Certificates or related multiple Classes of Exchangeable Certificates (such multiple Classes referred to as an "Exchangeable Combination").

The descriptions in the related prospectus supplement of the Certificates of a Series that includes Exchangeable REMIC Certificates and Exchangeable Certificates, including descriptions of principal and interest distributions, registration and denominations of Certificates, credit enhancement, prepayment and yield considerations, tax and legal investment considerations and ERISA considerations, also will apply to each Class of Exchangeable REMIC Certificates and Exchangeable Certificates. The related prospectus supplement will separately describe the prepayment and yield considerations applicable to, and the risks of investment in, each Class of Exchangeable REMIC Certificates and Exchangeable Certificates. For example, separate decrement tables and yield tables, if applicable, will be included for each Class of Exchangeable Certificates.

Exchanges

If a holder of Exchangeable REMIC Certificates elects to exchange its Exchangeable REMIC Certificates for related Exchangeable Certificates, then:

o the aggregate principal balance of the related Exchangeable Certificates received in the exchange, immediately after the exchange, will equal the aggregate principal balance, immediately prior to the exchange, of the Exchangeable REMIC Certificates so exchanged (for purposes of an exchange, Interest Only Certificates will have a principal balance of zero);

o the aggregate amount of principal or interest payable on each Distribution Date with respect to the related Exchangeable Certificates received in the exchange will equal the aggregate amount of principal or interest that would have been payable on each Distribution Date with respect to the Exchangeable REMIC Certificates so exchanged as if the exchange had not occurred; and

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o the Class or Classes of Exchangeable REMIC and Exchangeable Certificates will be exchanged in the applicable proportions, if any, described in the applicable prospectus supplement.

Different types of combinations may exist. Any individual Series of Certificates may have multiple types of Combinations. Some examples of Combinations of Exchangeable REMIC Certificates and Exchangeable Certificates that differ in their interest characteristics include:

o Floating Rate Certificates and Inverse Floating Rate Certificates that are Exchangeable REMIC Certificates may be exchangeable, together, for Related Fixed Rate Certificates. In such a Combination, the Floating Rate Certificates and Inverse Floating Rate Certificates would produce, in the aggregate, an annual interest amount equal to that generated by the Related Fixed Rate Certificates. In addition, the aggregate principal balance of a Class of Floating Rate Certificates and a Class of Inverse Floating Rate Certificates would equal the aggregate principal balance of the Related Fixed Rate Certificates.

o Interest Only Certificates and Principal Only Certificates that are Exchangeable REMIC Certificates may be exchangeable, together, for related Exchangeable Certificates that are entitled to both principal and interest payments. In such a Combination, the principal balance of the Class of related Exchangeable Certificates would be equal to the principal balance of the Class of Principal Only Certificates, and the interest rate on the Class of related Exchangeable Certificates, when applied to the principal balance of this Related Class, would generate interest equal to the annual interest amount of the Interest Only Certificates.

o Two Classes of Fixed Rate Certificates that are Exchangeable REMIC Certificates with different interest rates may be exchangeable, together, for a single Class of related Exchangeable Certificates with a fixed interest rate. In such a Combination, the principal balance of the single Class of related Exchangeable Certificates would be equal to the aggregate principal balance of the two Classes of Exchangeable REMIC Certificates, and the single Class of related Exchangeable Certificates would have a fixed interest rate that, when applied to the aggregate principal balance of the two Classes of Exchangeable REMIC Certificates, would generate interest equal to the aggregate annual interest amount of the two Classes of Exchangeable REMIC Certificates.

In some Series, a Certificateholder may be able to exchange its Exchangeable REMIC Certificates for other related Exchangeable Certificates that have different principal payment characteristics. Some examples of Combinations that differ in the principal payment characteristics include:

o A Class of Exchangeable REMIC Certificates that is a Class of Accrual Certificates, and a second Class of Exchangeable REMIC Certificates that is a Class of Accretion Directed Certificates and receives all of the interest accrued on the Class of Accrual Certificates for so long as the Accrual Certificates are accreting, may be exchangeable, together, for a single Class of related Exchangeable Certificates that receives payments of interest continuously from the first Distribution Date on which it receives interest until it is retired.

o A Class of Exchangeable REMIC Certificates that is a Class of PAC, Scheduled Amortization or TAC Certificates, and a Class of Exchangeable REMIC Certificates that is a Class of Companion Certificates, may be exchangeable, together, for a Class of related Exchangeable Certificates that receives principal payments without regard to the amortization schedule for the Class of PAC, Scheduled Amortization or TAC Certificates from the first Distribution Date on which it receives principal until it is retired.

The holder of the Class or Classes of Exchangeable Certificates in any of the example Combinations described above may also exchange its Exchangeable Certificates for the related Exchangeable REMIC Certificates and this process may occur repeatedly in each direction.

A number of factors may limit the ability of a holder of Exchangeable REMIC Certificates or Exchangeable Certificates to effect an exchange. For example, the Certificateholder must own, at the time of the proposed exchange, the Class or Classes of Exchangeable REMIC Certificates or Exchangeable Certificates necessary to make the exchange in the necessary proportions. If a Certificateholder does not own the necessary Classes of Exchangeable REMIC Certificates or Exchangeable Certificates or does not own the necessary Classes of Exchangeable REMIC Certificates or Exchangeable Certificates in the proper proportions, the Certificateholder may

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not be able to obtain the desired Classes of Exchangeable REMIC Certificates or Exchangeable Certificates, as the case may be. The Certificateholder desiring to make the exchange may not be able to purchase the necessary Class of Exchangeable REMIC Certificates or Exchangeable Certificates from the then-current owner at a reasonable price, or the necessary proportion of the needed Class of Exchangeable REMIC Certificates or Exchangeable Certificates may no longer be available due to principal payments or prepayments that have been applied to, or losses that have been allocated to, that Class of Exchangeable REMIC Certificates or Exchangeable Certificates.

Procedures

The applicable prospectus supplement will describe the procedures that must be followed to make an exchange of Exchangeable REMIC Certificates and Exchangeable Certificates. A Certificateholder will be required to provide notice to the Master Servicer or Securities Administrator, as applicable, prior to the proposed exchange date within the time period specified in the applicable prospectus supplement. The notice must include, among other things, the outstanding principal balance or notional amount of the Exchangeable REMIC Certificates or Exchangeable Certificates to be exchanged and the related Exchangeable REMIC Certificates or Exchangeable Certificates to be received, and the proposed exchange date. When the Master Servicer or Securities Administrator, as applicable, receives this notice, it will provide instructions to the Certificateholder regarding delivery of the Exchangeable REMIC Certificates or Exchangeable Certificates and payment of the exchange fee. A Certificateholder's notice to the Master Servicer or Securities Administrator, as applicable, will become irrevocable on the second business day prior to the proposed exchange date specified in the applicable prospectus supplement. Any Exchangeable REMIC Certificates or Exchangeable Certificates that are Book-Entry Certificates will be subject to DTC's Rules.

If the applicable prospectus supplement describes exchange proportions for a Combination of Classes of Exchangeable REMIC Certificates or Exchangeable Certificates, these proportions will be based on the original, rather than the outstanding, principal balances or notional amounts of these Classes.

Distributions on an Exchangeable REMIC Certificate or Exchangeable Certificate received in an exchange will be made as described in the applicable prospectus supplement. Distributions will be made to the applicable Certificateholder of record as of the applicable Record Date.

PREPAYMENT AND YIELD CONSIDERATIONS

Pass-Through Rates

Any Class of Certificates of a Series may have a fixed Pass-Through Rate, or a Pass-Through Rate which varies based on changes in an index or based on changes with respect to the underlying Mortgage Assets (such as, for example, varying on the basis of changes in the weighted average Net Mortgage Interest Rate of the underlying Mortgage Loans or the weighted average Net Mortgage Certificate Pass-Through Rate of the underlying Mortgage Certificates, as applicable).

The prospectus supplement for each Series will specify the range and the weighted average of the Mortgage Interest Rates or Mortgage Certificate Pass-Through Rates, as applicable, and, if applicable, Net Mortgage Interest Rates or Net Mortgage Certificate Pass-Through Rates, as applicable, for the Mortgage Assets underlying such Series as of the Cut-Off Date. If the Trust Estate includes adjustable rate Mortgage Assets or includes Mortgage Assets with different Net Mortgage Interest Rates or Net Mortgage Certificate Pass-Through Rates, as applicable, the weighted average Net Mortgage Interest Rate or weighted average Net Mortgage Certificate Pass-Through Rate, as applicable, may vary from time to time as set forth below. See "The Trust Estates." The prospectus supplement for a Series will also specify the initial Pass-Through Rate for each Class of Certificates of such Series and will specify whether each such Pass-Through Rate is fixed or is variable.

The Net Mortgage Interest Rate for any adjustable rate Mortgage Loan will change with any changes in the index specified in the applicable prospectus supplement on which such Mortgage Interest Rate adjustments are based, subject to any applicable periodic or aggregate caps or floors on the related Mortgage Interest Rate. The weighted average Net Mortgage Interest Rate or Net Mortgage Certificate Pass-Through Rate, as applicable, with respect to any Series may vary due to changes in the Net Mortgage Interest Rates or Net Mortgage Certificate Pass-Through Rates of the related Mortgage Assets, to the timing of the Mortgage Interest Rate or Mortgage Certificate

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Pass-Through Rate readjustments of such Mortgage Assets and to different rates of payment of principal of fixed- or adjustable rate Mortgage Assets bearing different Mortgage Interest Rates or Mortgage Certificate Pass-Through Rates, as applicable.

Effects of Defaults

The rate of defaults on the Mortgage Loans will also affect the rate and timing of principal payments on the Mortgage Loans. In general, defaults on mortgage loans are expected to occur with greater frequency in their early years. The rate of default on Mortgage Loans that are secured by non-owner occupied properties, Mortgage Loans with higher Loan-to-Value Ratios and Mortgage Loans made to borrowers with higher debt-to-income ratios or borrowers approved under a No Ratio program, may be higher than for other types of Mortgage Loans. As a result of the Mortgage Loans being originated using "alternative" underwriting standards that, in certain respects, may be less stringent than the "general" standards applied by the Sponsor, the Mortgage Loans may experience rates of delinquency and cumulative loss that are higher than those experienced by mortgage loans that satisfy the standards generally applied by the Sponsor.

Scheduled Delays in Distributions

At the date of initial issuance of the Certificates of each Series offered hereby, the initial purchasers of a Class of Certificates may be required to pay accrued interest at the applicable Pass-Through Rate for such Class from the Cut-Off Date for such Series to, but not including, the date of issuance. The effective yield to Certificateholders will be below the yield otherwise produced by the applicable Pass-Through Rate because the distribution of principal and interest which is due on each Due Date will not be made until the 25th day (or, if such day is not a business day, the first business day following the 25th day) of the month in which such Due Date occurs (or until such other Distribution Date specified in the applicable prospectus supplement).

Effect of Principal Prepayments

When a Mortgage Loan is prepaid in full, the mortgagor pays interest on the amount prepaid only to the date of prepayment and not thereafter. Liquidation Proceeds (as defined herein) and amounts received in settlement of insurance claims are also likely to include interest only to the time of payment or settlement. When a Mortgage Loan is prepaid in full or in part, an interest shortfall may result depending on the timing of the receipt of the prepayment and the timing of when those prepayments are passed through to Certificateholders. To partially mitigate this reduction in yield with respect to Prepayments in Full, the Master Servicer will be obligated, on or before each Distribution Date, to pay Compensating Interest. No comparable interest shortfall coverage will be provided by the Master Servicer with respect to liquidations of any Mortgage Loans or partial principal payments. Any interest shortfall arising from prepayments not so covered or from liquidations will be covered as provided in the applicable prospectus supplement. See "Description of the Certificates -- Distributions to Certificateholders -- Distributions of Interest."

A lower rate of principal prepayments than anticipated would negatively affect the total return to investors in any Certificates of a Series that are offered at a discount to their principal amount and a higher rate of principal prepayments than anticipated would negatively affect the total return to investors in the Certificates of a Series that are offered at a premium to their principal amount. The yield on Certificates that are entitled solely or disproportionately to distributions of principal or interest may be particularly sensitive to prepayment rates, and further information with respect to yield on such Certificates will be included in the applicable prospectus supplement.

Weighted Average Life of Certificates

The Mortgage Loans may be prepaid in full or in part at any time. Mortgage Loans generally will not provide for a prepayment penalty but may so provide if indicated in the applicable prospectus supplement. Fixed rate Mortgage Loans generally will contain due-on-sale clauses permitting the mortgagee to accelerate the maturities of the Mortgage Loans upon conveyance of the related Mortgaged Properties, and adjustable rate Mortgage Loans under certain circumstances will permit creditworthy borrowers to assume the then-outstanding indebtedness on the Mortgage Loans.

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Prepayments on Mortgage Loans are commonly measured relative to a prepayment standard or model. The prospectus supplement for each Series of Certificates may describe one or more such prepayment standards or models and contain tables setting forth the weighted average life of each Class and the percentage of the original aggregate principal balance of each Class that would be outstanding on specified Distribution Dates for such Series and the projected yields to maturity on certain Classes thereof, in each case based on the assumptions stated in such prospectus supplement, including assumptions that prepayments on the Mortgage Loans (or the Underlying Loans in the case of a Series issued by a Trust containing Mortgage Certificates) are made at rates corresponding to various percentages of the prepayment standard or model specified in such prospectus supplement.

There is no assurance that prepayment of the Mortgage Loans underlying a Series of Certificates will conform to any level of the prepayment standard or model specified in the applicable prospectus supplement. A number of factors, including but not limited to homeowner mobility, economic conditions, natural disasters, changes in mortgagors' housing needs, job transfers, unemployment or, in the case of borrowers relying on commission income and self-employed borrowers, significant fluctuations in income or adverse economic conditions, mortgagors' net equity in the properties securing the mortgage loans, including the use of second or "home equity" mortgage loans by mortgagors or the use of the properties as second or vacation homes, servicing decisions, enforceability of due-on-sale clauses, mortgage market interest rates, mortgage recording taxes, competition among mortgage loan originators resulting in reduced refinancing costs, reduction in documentation requirements and willingness to accept higher Loan-to-Value Ratios, and the availability of mortgage funds, may affect prepayment experience. In general, however, if prevailing mortgage interest rates fall below the Mortgage Interest Rates borne by the Mortgage Loans underlying a Series of Certificates, the prepayment rates of such Mortgage Loans are likely to be higher than if prevailing rates remain at or above the rates borne by such Mortgage Loans. Conversely, if prevailing mortgage interest rates rise above the Mortgage Interest Rates borne by the Mortgage Loans, the Mortgage Loans are likely to experience a lower prepayment rate than if prevailing rates remain at or below such Mortgage Interest Rates. However, there can be no assurance that prepayments will rise or fall according to such changes in mortgage interest rates. It should be noted that Certificates of a Series may evidence an interest in a Trust Estate with different Mortgage Interest Rates or Mortgage Certificate Pass-Through Rates. Accordingly, the prepayment experience of such Certificates will to some extent be a function of the mix of interest rates of the Mortgage Loans and/or Mortgage Certificates. The amount of equity in a Mortgaged Property may also affect the rate of prepayments because as the amount of equity in the Mortgaged Property increases, the related borrower is more likely to enter into a "cash-out" refinancing of the Mortgaged Property, which will result in a prepayment in full of the Mortgage Loan. In addition, the terms of the Underlying Servicing Agreements will require the related Servicer to enforce any due-on-sale clause to the extent it has knowledge of the conveyance or the proposed conveyance of the underlying Mortgaged Property; provided, however, that any enforcement action that the Servicer determines would jeopardize any recovery under any related primary mortgage insurance policy will not be required and provided, further, that the Servicer may permit the assumption of defaulted Mortgage Loans. See "Servicing of the Mortgage Loans--Enforcement of Due-on-Sale Clauses; Realization Upon Defaulted Mortgage Loans" and "Certain Legal Aspects of the Mortgage Loans--Due-On-Sale Clauses" for a description of certain provisions of each Pooling and Servicing Agreement and certain legal developments that may affect the prepayment experience on the Mortgage Loans.

The effect of prepayments on the weighted average lives of Certificates backed by Mortgage Certificates will be a function of the rate of prepayments on the Underlying Loans and the allocation of such prepayments among the Mortgage Certificates and the other Certificates of the related Series.

Prepayments on the Mortgage Assets are also affected by the obligation or right of the Depositor, Wells Fargo Bank or other party specified in the applicable prospectus supplement to repurchase or purchase certain or all of the Mortgage Assets under certain circumstances. The Depositor will be obligated, under certain circumstances, to repurchase certain of the Mortgage Assets. In addition, if specified in the applicable prospectus supplement, the Pooling and Servicing Agreement will permit, but not require, the Depositor, and the terms of certain insurance policies relating to the Mortgage Loans may permit the applicable insurer, to purchase any Mortgage Loan which is in default or as to which default is reasonably foreseeable. The proceeds of any such purchase or repurchase will be deposited in the Certificate Account and such purchase or repurchase will have the same effect as a prepayment in full of the related Mortgage Loan. See "The Pooling and Servicing Agreement--Assignment of Mortgage Loans to the Trustee" and "--Optional Purchases." In addition, if so specified in the applicable prospectus supplement, the Depositor or another person identified therein will have the option to purchase all, but not less than all, of the Mortgage Assets in any Trust Estate under the limited conditions specified in such prospectus supplement. For any

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Series of Certificates for which an election has been made to treat the Trust Estate (or one or more segregated pools of assets therein) as a REMIC, any such purchase or repurchase may be effected only pursuant to a "qualified liquidation," as defined in Code Section 860F(a)(4)(A). See "The Pooling and Servicing Agreement--Termination; Optional Purchase of Mortgage Loans."

Refinancings

At the request of the mortgagor, a Servicer, including Wells Fargo Bank, may allow the refinancing of a Mortgage Loan in any Trust Estate serviced by such Servicer by accepting prepayments thereon and permitting a new loan secured by a Mortgage on the same property. Upon such refinancing, the new loan will not be included in the Trust Estate. A mortgagor may be legally entitled to require the Servicer to allow such a refinancing. Any such refinancing will have the same effect as a prepayment in full of the related Mortgage Loan. In this regard a Servicer may, from time to time, implement programs designed to encourage refinancing through such Servicer, including but not limited to general or targeted solicitations, or the offering of pre-approved applications, reduced or nominal origination fees or closing costs, or other financial incentives. A Servicer may also modify the payment terms of a defaulted Mortgage Loan or encourage selling a Mortgaged Property securing a defaulted Mortgage Loan for less than the unpaid principal balance of such Mortgage Loan.

Wells Fargo Bank has a retention program applicable to its servicing portfolio. Provided the borrower is current in his or her mortgage payment obligations, Wells Fargo Bank may agree to refinance the mortgage loan in order to reduce the borrower's mortgage interest rate, through the extension of a replacement loan or the execution of a modification agreement, without the application of any significant new borrower credit or property underwriting standards. Any such refinancing will have the same effect as a prepayment in full of the related Mortgage Loan. See "Wells Fargo Bank's Mortgage Loan Programs--Mortgage Loan Underwriting--Retention Program Standards." The streamlined procedures, minimal borrower cost and the absence of significant underwriting standards associated with this retention program may result in an increase in the number of Mortgage Loans eligible for refinancing and a narrowing of the interest rate differential that may otherwise need to exist before a refinancing is practical and economical for the borrower. These factors, together with increased borrower sophistication in general regarding the benefits of refinancing may also result in a significant increase in the rate of prepayments on the Mortgage Loans. In addition, the success of Wells Fargo Bank over time in attracting borrowers to its retention program who are current in their mortgage payment obligations may result in a higher proportion of Mortgage Loans not eligible for such program remaining in a Trust Estate, thereby increasing the relative percentage of delinquent Mortgage Loans in such Trust Estate.

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SERVICING OF THE MORTGAGE LOANS

The servicing of the Mortgage Loans in a Trust underlying a Series of Certificates will be performed by one or more Servicers, which may include Wells Fargo Bank or its affiliates. In addition, Wells Fargo Bank will act as master servicer with respect to each Series of Certificates issued by a Trust containing Mortgage Loans. The applicable prospectus supplement will identify
(i) each Servicer affiliated with Wells Fargo Bank, (ii) each Servicer that services 10% or more of the Mortgage Loans and (iii) any other material servicer that is responsible for performing an aspect of the servicing on which the performance of the related Mortgage Loans or Certificates are materially dependent.

The following is a summary of the material servicing provisions of the Underlying Servicing Agreements and the Pooling and Servicing Agreement that have been filed as exhibits to the registration statement of which this prospectus forms a part. The Pooling and Servicing Agreement (and, to the extent material, the Underlying Servicing Agreements) for each Series backed by Mortgage Loans will be filed with the SEC following the date of initial issuance of the related Certificates.

The Master Servicer

General

The master servicer (the "Master Servicer") with respect to each Series of Certificates issued by a Trust containing Mortgage Loans will be Wells Fargo Bank, as Sponsor of such Series. See "The Sponsor." Wells Fargo Bank conducts its master servicing and securities administration services at its offices in Columbia, Maryland. Its address there is 9062 Old Annapolis Road, Columbia, Maryland 21045-1951 and its telephone number is (410) 884-2000. The Master Servicer generally will (a) be responsible under each Pooling and Servicing Agreement for providing general administrative services for the Trust Estate, including, among other things, (i) administering and supervising the performance by the Servicers of their duties and responsibilities under the Underlying Servicing Agreements, (ii) oversight of payments received on Mortgage Loans,
(iii) monitoring the amounts on deposit in various trust accounts, (iv) calculation of the amounts payable to Certificateholders on each Distribution Date, (v) preparation of periodic reports to the Certificateholders with respect to the foregoing matters, (vi) preparation of federal and applicable state and local tax and information returns; (vii) preparation of reports, if any, required under the Exchange Act and (viii) performing certain of the servicing obligations of a terminated Servicer as described below under "--The Servicers";
(b) maintain any mortgage pool insurance policy, mortgagor bankruptcy bond, special hazard insurance policy or other form of credit support that may be required with respect to any such Series and (c) make advances of delinquent payments of principal and interest on the Mortgage Loans to the limited extent described herein under the heading "Servicing of Mortgage Loans--Periodic Advances and Limitations Thereon," if such amounts are not advanced by a Servicer (other than Wells Fargo Bank as a Servicer). The Master Servicer will also perform additional duties as described in the applicable Pooling and Servicing Agreement. The Master Servicer will be entitled to receive a portion of the interest payments on the Mortgage Loans included in the Trust Estate for such a Series to cover its fees as Master Servicer. The Master Servicer will be entitled to retain Liquidation Profits as additional master servicing compensation to the extent a Servicer is not entitled to retain such amounts as additional servicing compensation under the applicable Underlying Servicing Agreement. In addition, as additional compensation, the Master Servicer will be entitled to any income from investments of funds in the Certificate Account and Payment Account and any Liquidation Profits to which a Servicer is not entitled under the related Underlying Servicing Agreement. The Master Servicer may subcontract with any entity the obligations of the Master Servicer under any Pooling and Servicing Agreement. The Master Servicer will remain primarily liable for any such contractor's performance in accordance with the applicable Pooling and Servicing Agreement. The Master Servicer may be released from its obligations in certain circumstances.

The Master Servicer will be required to pay certain expenses incurred in connection with the administration of the Trust Estate, which will generally include, the fees and disbursements of any custodian, the fees of the Trustee or co-trustee, fees due to the independent accountants and expenses incurred in connection with distributions and reports to Certificateholders. Certain of these expenses will be reimbursable to the Master Servicer pursuant to the terms of the applicable Pooling and Servicing Agreement. Expenses that are reimbursable to the Master Servicer include, but are not limited to, legal expenses incurred in connection with the prosecution or defense of any legal

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action (including any such expenses incurred by the Trustee), expenses incurred as a result of a transfer of servicing, certain taxes incurred by the Master Servicer and certain additional compensation payable to the Master Servicer in the event its tax reporting obligations are materially increased as a result of changes to certain tax laws as set forth in the Pooling and Servicing Agreement. Any loss to the Trust Estate as a result of such reimbursement will be allocated first to the Subordinated Certificates of a Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable prospectus supplement.

The Master Servicer may not resign from its obligations and duties under the Pooling and Servicing Agreement for a Series, except (i) upon the appointment of a successor and the receipt by the Trustee of a letter from each Rating Agency rating the affected Series of Certificates that its resignation and the appointment of a successor will not result in a downgrade of such Certificates,
(ii) upon its determination that its duties thereunder are no longer permissible under applicable law or (iii) in the case of an assignment of its rights and delegation or its duties described below. No such resignation will become effective until the Trustee for such Series or a successor master servicer has assumed the Master Servicer's responsibilities, duties, liabilities and obligations under the Pooling and Servicing Agreement. If the Master Servicer resigns for any of the foregoing reasons and the Trustee is unable or unwilling to assume responsibility for its duties under the Pooling and Servicing Agreement, it may appoint another institution to so act as described under "The Pooling and Servicing Agreement--Rights Upon Event of Default."

The Pooling and Servicing Agreement will also provide that neither the Master Servicer nor any subcontractor, nor any director, officer, employee or agent of any of them, will be under any liability to the Trust Estate or the Certificateholders, for the taking of any action or for refraining from the taking of any action in good faith pursuant to the Pooling and Servicing Agreement, or for errors in judgment; provided, however, that neither the Master Servicer, any subcontractor, nor any such person will be protected against any liability that would otherwise be imposed by reason of willful misfeasance, bad faith or gross negligence in the performance of his or its duties or by reason of reckless disregard of his or its obligations and duties thereunder. The Pooling and Servicing Agreement will further provide that the Master Servicer, any subcontractor, and any director, officer, employee or agent of either of them shall be entitled to indemnification by the Trust Estate and will be held harmless against any loss, liability or expense incurred in connection with the performance of their duties and obligations and any legal action relating to the Pooling and Servicing Agreement, the Certificates or the Mortgage Loans of a Series, other than any loss, liability or expense incurred by reason of willful misfeasance, bad faith or gross negligence in the performance of his or its duties thereunder or by reason of reckless disregard of his or its obligations and duties thereunder. In addition, the Pooling and Servicing Agreement will provide that the Master Servicer will not be under any obligation to appear in, prosecute or defend any legal action unless such action is related to its duties under the Pooling and Servicing Agreement and, in its opinion, does not involve it in any expense or liability. The Master Servicer may, however, in its discretion, undertake any such action deemed by it necessary or desirable with respect to the Pooling and Servicing Agreement and the rights and duties of the parties thereto and the interests of the Certificateholders thereunder if the Certificateholders offer the Master Servicer reasonable security or indemnity against the costs, expenses and liabilities that may be incurred. In such event, the legal expenses and costs of such action and any liability resulting therefrom will be expenses, costs and liabilities of the Trust Estate and the Master Servicer will be entitled to be reimbursed therefor out of the Certificate Account, and any loss to the Trust Estate arising from such right of reimbursement will be allocated first to the Subordinated Certificates of a related Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable Pooling and Servicing Agreement.

Any person into which the Master Servicer may be merged or consolidated, or any person resulting from any merger, conversion or consolidation to which the Master Servicer is a party, or any person succeeding to the business through the transfer of substantially all of its assets or all assets relating to such business, or otherwise, of the Master Servicer will be the successor of the Master Servicer under the Pooling and Servicing Agreement for each applicable Series provided that such successor or resulting entity has a net worth of not less than $15,000,000 and is qualified to service mortgage loans for Fannie Mae or Freddie Mac.

The Master Servicer also has the right, without the prior written consent of the Trustee, to assign its rights and delegate its duties and obligations under the Pooling and Servicing Agreement for each applicable Series; provided that, if the Master Servicer desires to be released from its obligations under the Pooling and Servicing Agreement,

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(i) the purchaser or transferee accepting such assignment or delegation is qualified to service mortgage loans for Fannie Mae or Freddie Mac, (ii) the purchaser executes and delivers to the Depositor and the Trustee an agreement, in form and substance reasonably satisfactory to the Trustee, which contains an assumption by such purchaser or transferee of the due and punctual performance and observance of each covenant and condition to be performed or observed by the Master Servicer under the Pooling and Servicing Agreement from and after the date of such agreement; and (iii) each applicable Rating Agency's rating of any Certificates for such Series in effect immediately prior to such assignment, sale or transfer would not be qualified, downgraded or withdrawn as a result of such assignment, sale or transfer and the Certificates are not reasonably likely to be placed on credit review status by any such Rating Agency. The Master Servicer will be released from its obligations under the Pooling and Servicing Agreement upon any such assignment and delegation, except that the Master Servicer will remain liable for all liabilities and obligations incurred by it prior to the time that the conditions contained in clauses (i), (ii) and (iii) above are met. In addition, the Master Servicer shall have the right, without the written consent of the Trustee, to delegate to, subcontract with, authorize, or appoint an affiliate of the Master Servicer to perform and carry out any duties, covenants or obligations to be performed and carried out by the Master Servicer under the Pooling and Servicing Agreement and will so to delegate, subcontract, authorize or appoint to an affiliate of the Master Servicer any duties, covenants or obligations to be performed and carried out by the Master Servicer to the extent that such duties, covenants or obligations are to be performed in any state or states in which the Master Servicer is not authorized to do business as a foreign corporation but in which the affiliate is so authorized. In the event of any assignment of rights and delegation of duties by the Master Servicer, the Master Servicer will report such event on Form 8-K for so long as the related Issuing Entity is subject to the reporting requirements of the Exchange Act.

The Trustee or a successor master servicer is entitled to be reimbursed for its costs in effecting a master servicing transfer from the Master Servicer. In the event that the predecessor master servicer fails to reimburse the Trustee or successor master servicer, as applicable, the Trustee or successor master servicer will be entitled to reimbursement from the assets of the related Trust.

Master Servicing Experience and Procedures of Wells Fargo Bank

Wells Fargo Bank, including its predecessors, has been involved with the master servicing of residential mortgage loans since 1989. These master servicing activities include independently calculating monthly loan balances based on servicer data, comparing its results to servicer loan-level reports and reconciling any discrepancies with the servicers. The master servicing activities also include reviewing the servicing of defaulted loans for compliance with the terms of the applicable Pooling and Servicing Agreement. The master servicing activities are handled at Wells Fargo Bank's location in Columbia, Maryland.

The following table shows the number of issuances and the aggregate principal balances (as of the end of each year listed) of residential mortgage-backed securities for which Wells Fargo Bank acted as master servicer during each of the periods indicated:

            2005                             2006                            2007
            ----                             ----                            ----

 No. of         Aggregate        No. of         Aggregate        No. of        Aggregate
Issuances   Principal Balance   Issuances   Principal Balance   Issuances  Principal Balance
  1,096      $542,500,639,530     1,427     $748,854,234,778      1,676     $846,565,292,572

In addition, Wells Fargo Bank will be responsible for securities administration of each Trust. Wells Fargo Bank, including its predecessors, has been involved with the securities administration of residential mortgage loans, commercial mortgage loans, auto loans, student loans and collateralized debt obligations. Wells Fargo Bank, including its predecessors, has been involved in the securities administration of residential mortgage loans since 1989. These securities administration activities, which include calculations of payments on certificates are handled at Wells Fargo Bank's location in Columbia, Maryland.

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The following table shows the number of issuances and the aggregate principal balances (as of the end of each year listed) of residential mortgage-backed securities which Wells Fargo Bank acted as securities administrator during each of the periods indicated:

            2005                             2006                            2007
            ----                             ----                            ----

 No. of         Aggregate        No. of         Aggregate        No. of        Aggregate
Issuances   Principal Balance   Issuances   Principal Balance   Issuances  Principal Balance
  2,131      $766,507,104,520     2,767     $1,006,418,886,758   3,306    $1,120,224,428,393

The Servicers

For each Series issued by a Trust containing Mortgage Loans, Wells Fargo Bank and one or more other servicers (each, a "Servicer") specified in the applicable prospectus supplement, will provide certain customary servicing functions with respect to Mortgage Loans pursuant to separate servicing agreements with the Master Servicer, the Sponsor or an affiliate thereof (each, an "Underlying Servicing Agreement"). The rights of the Master Servicer, the Sponsor or such affiliate under the applicable Underlying Servicing Agreements in respect of the Mortgage Loans included in the Trust Estate for any such Series will be assigned (directly or indirectly) to the Trustee for such Series. The Servicers may be entitled to withhold their Servicing Fees and certain other fees and charges from remittances of payments received on Mortgage Loans serviced by them.

Each Servicer generally will be approved by Fannie Mae or Freddie Mac as a servicer of mortgage loans and must be approved by the Master Servicer. In determining whether to approve a Servicer, the Master Servicer will perform a review of the Servicer that includes minimum net worth requirements, servicing experience, errors and omissions and fidelity bond coverage and other standards to be set forth in the applicable Underlying Servicing Agreement. In addition, the Master Servicer's mortgage servicing personnel will review the Servicer's servicing record and evaluate the ability of the Servicer to conform with required servicing procedures. Once a Servicer is approved, the Master Servicer will continue to monitor the compliance of the Servicer according to the Underlying Servicing Agreement on an annual basis.

The duties to be performed by each Servicer include collection and remittance of principal and interest payments on the Mortgage Loans, administration of mortgage escrow accounts, collection of insurance claims, foreclosure procedures, and, if necessary, the advance of funds to the extent certain payments are not made by the mortgagor and have not been determined by the Servicer to be not recoverable under the applicable insurance policies with respect to such Series, from proceeds of liquidation of such Mortgage Loans or otherwise. Each Servicer also will provide such accounting and reporting services as are necessary to enable the Master Servicer to provide required information to the Trustee or Paying Agent with respect to the Mortgage Loans included in the Trust Estate for such Series. Each Servicer is entitled to a periodic Servicing Fee equal to a specified percentage of the outstanding principal balance of each Mortgage Loan serviced by such Servicer. With the consent of the Master Servicer, any of the servicing obligations of a Servicer may be delegated to another person approved by the Master Servicer. In addition, certain limited duties of a Servicer may be delegated without consent. In the event a Servicer delegates obligations to a subservicer that meets the thresholds provided in Item 1108(a)(3) of Regulation AB (17 C.F.R. 229.1108), the applicable prospectus supplement will provide the disclosure required by Item 1108(b) and (c) of Regulation AB (17 C.F.R. 229.1108). In the event that such appointment occurs after the issuance of the related series of Certificates, the Master Servicer will report such appointment on Form 8-K for so long as the related Issuing Entity is subject to the reporting requirements of the Exchange Act.

The Trustee, or if so provided in the applicable Pooling and Servicing Agreement, the Master Servicer, may terminate a Servicer who has failed to comply with its covenants or breached one of its representations contained in the Underlying Servicing Agreement or in certain other circumstances. Upon termination of a Servicer (other than Wells Fargo Bank as a Servicer), the Master Servicer will assume certain servicing obligations of the terminated Servicer, or, at its option, may appoint a substitute Servicer acceptable to the Trustee (which substitute Servicer may be Wells Fargo Bank) to assume the servicing obligations of the terminated Servicer. The Master Servicer's obligations to act as a servicer following the termination of an Underlying Servicing Agreement will not, however,

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require the Master Servicer to purchase a Mortgage Loan from a Trust Estate due to a breach by such Servicer of a representation or warranty in respect of such Mortgage Loan. Upon the termination of Wells Fargo Bank as Servicer, the Trustee will appoint a successor. See "--Servicer Defaults" below.

The Trustee or a successor servicer is entitled to be reimbursed for its costs in effecting a servicing transfer from the predecessor servicer or from the Master Servicer, who is entitled to reimbursement from the predecessor servicer. In the event that the predecessor servicer fails to reimburse the Master Servicer or the Trustee, the Master Servicer or the Trustee will be entitled to reimbursement from the assets of the related Trust.

The applicable Underlying Servicing Agreement provides that neither Wells Fargo Bank (as a Servicer), any subservicer appointed by it, nor any of their respective partners, directors, officers, employees or agents, or its delegees will be under any liability to the Master Servicer or the Trustee for any action taken or for refraining from the taking of any action in good faith pursuant to the related Underlying Servicing Agreement, or for errors in judgment; provided, however, that Wells Fargo Bank, any subservicer or any of their respective partners, directors, officers, employees or agents, or its delegees are not protected against any liability which would otherwise be imposed by reason of willful misfeasance, bad faith or gross negligence in the performance of his or its duties or by reason of reckless disregard of his or its obligations and duties under the related Underlying Servicing Agreement.

The applicable Underlying Servicing Agreement provides that Wells Fargo Bank (as a Servicer) may not sell or transfer the servicing of the applicable Mortgage Loans without the prior written consent of the Master Servicer. Any proposed transferee of servicing must agree to enter into a servicing agreement with the Master Servicer substantially in the form of the original Underlying Servicing Agreement and must be approved by the Master Servicer and the applicable Rating Agencies. The applicable Underlying Servicing Agreement permits Wells Fargo Bank to delegate certain of its duties under the applicable Underlying Servicing Agreement, provided that Wells Fargo Bank shall remain liable to the Master Servicer for the performance of the Servicer's duties and obligations under the applicable Underlying Servicing Agreement.

The information provided in the two preceding paragraphs describes provisions relating to the Underlying Servicing Agreement of Wells Fargo Bank. Any provisions of the Underlying Servicing Agreements of the other Servicers that are not substantially similar to the provisions set forth above will be described in the applicable prospectus supplement.

Servicing Experience and Procedures of Wells Fargo Bank

Servicing Experience

Wells Fargo Bank, including its predecessors, has many years of experience in servicing residential mortgage loans, commercial mortgage loans, auto loans, home equity loans, credit card receivables and student loans. Wells Fargo Bank, including its predecessors, has been servicing residential mortgage loans since 1974. These servicing activities, which include collections, loss mitigation, default reporting, bankruptcy, foreclosure and REO Property management, are handled at various Wells Fargo Bank locations including Frederick, Maryland, Fort Mill, South Carolina and other mortgage loan servicing centers.

Wells Fargo Bank's servicing portfolio of residential mortgage loans (which includes Alt-A Prime Fixed Rate Loans, Alt-A Prime Adjustable Rate Loan, Alt-A Minus Fixed Rate Loans and Alt-A Minus Adjustable Rate Loans as well as other types of residential mortgage loans serviced by Wells Fargo Bank) has grown from approximately $450 billion as of the end of 2000 to approximately $1.47 trillion as of the end of 2007.

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Wells Fargo Bank currently services Alt-A Prime Mortgage Loans in the same manner as it services mortgage loans originated pursuant to its "prime" underwriting guidelines. The table below sets forth for each of the dates indicated the number and aggregate unpaid principal balance of first lien, non-subprime, residential mortgage loans serviced by Wells Fargo Bank (other than any mortgage loans serviced for Fannie Mae or Freddie Mac and certain mortgage loans serviced for the Federal Home Loan Banks, mortgage loans insured or guaranteed by the Government National Mortgage Association, Federal Housing Administration or Department of Veterans Affairs or mortgage loans with respect to which Wells Fargo Bank has acquired the servicing rights, acts as subservicer, or acts as special servicer):

           As of                                      As of                                     As of
     December 31, 2005(1)                      December 31, 2006(1)                      December 31, 2007(2)
     --------------------                      --------------------                      --------------------
                 Aggregate Unpaid                             Aggregate                                  Aggregate
                     Principal                             Unpaid Principal                          Unpaid Principal
  No. of Loans   Balance of Loans         No. of Loans     Balance of Loans         No. of Loans     Balance of Loans
634,103          $229,014,862,911          646,723         $258,646,782,192         709,651          $298,085,009,923


(1) Includes mortgage loans originated pursuant to Wells Fargo Bank's underwriting guidelines for Alt-A Minus Mortgage Loans.

(2) Excludes mortgage loans originated pursuant to Wells Fargo Bank's underwriting guidelines for Alt-A Minus Mortgage Loans.

Wells Fargo Bank currently services Alt-A Minus Mortgage Loans in the same manner as it services first lien mortgage loans originated pursuant to its "subprime" underwriting guidelines (such mortgage loans, "Subprime First Lien Loans") and second lien mortgage loans originated pursuant to its "subprime" underwriting guidelines (such mortgage loans, "Subprime Second Lien Loans"). The table below sets forth for each of the dates indicated the number and aggregate unpaid principal balance of Subprime First Lien Loans, Subprime Second Lien Loans and Alt-A Minus Mortgage Loans serviced by Wells Fargo Bank (other than any mortgage loans serviced for Fannie Mae or Freddie Mac and certain mortgage loans serviced for the Federal Home Loan Banks, mortgage loans insured or guaranteed by the Government National Mortgage Association, Federal Housing Administration or Department of Veterans Affairs or mortgage loans with respect to which Wells Fargo Bank has acquired the servicing rights, acts as subservicer, or acts as special servicer):

                                         As of                       As of                       As of
                                   December 31, 2005           December 31, 2006           December 31, 2007
                                 ---------------------       ---------------------       -------------------
                                            Aggregate                   Aggregate                   Aggregate
                                            Original                    Original                    Original
                                            Principal                   Principal                   Principal
Asset                          No. of      Balance of      No. of      Balance of      No. of      Balance of
Type                            Loans         Loans         Loans         Loans         Loans         Loans
----------------------------   -------   ---------------   -------   ---------------   -------   ---------------
Subprime First Lien Loans      173,411   $26,214,367,714   190,395   $29,252,542,517   157,402   $24,416,104,782
Subprime Second Lien Loans       9,116       353,218,934    18,483       711,917,795    16,153       632,728,745
Alt-A Minus Mortgage Loans**         -                 -    62,351    11,088,435,185    57,964    10,372,462,960


* Wells Fargo Bank did not have a material servicing portfolio of Subprime Second Lien Loans as of the dates indicated.

** Prior to 2006, Wells Fargo Bank included Alt-A Minus Mortgage Loans in its servicing portfolio of non-subprime mortgage loans as described in the preceding table.

Servicing Procedures

Shortly after the funding of a loan, various types of loan information are loaded into Wells Fargo Bank's automated loan servicing system. Wells Fargo Bank then makes reasonable efforts to collect all payments called for under the Mortgage Loan documents and will, consistent with the applicable Pooling and Servicing Agreement and applicable Underlying Servicing Agreement and any pool insurance policy, primary mortgage insurance policy, bankruptcy bond or alternative arrangements, follow such collection procedures as are customary with respect to loans that are comparable to the Mortgage Loans. Wells Fargo Bank may, in its discretion, (i) waive any assumption fee, late payment or other charge in connection with a Mortgage Loan and (ii) to the extent not

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inconsistent with the coverage of such Mortgage Loan by a pool insurance policy, primary mortgage insurance policy, bankruptcy bond or alternative arrangements, if applicable, waive, vary or modify any term of any Mortgage Loan or consent to the postponement of strict compliance with any such term or in any matter grant indulgence to any borrower, subject to the limitations set forth in the applicable Pooling and Servicing Agreement and the applicable Underlying Servicing Agreement.

Wells Fargo Bank's collections policy is designed to identify payment problems sufficiently early to permit Wells Fargo Bank to address such delinquency problems and, when necessary, to act to preserve equity in a pre-foreclosure Mortgaged Property. Borrowers are billed on a monthly basis in advance of the due date. If a borrower attempts to use Wells Fargo Bank's Voice Response Unit ("VRU") to obtain loan information on or after a date on which a late charge is due, the VRU automatically transfers the call to the collection area. Collection procedures commence upon identification of a past due account by Wells Fargo Bank's automated servicing system. If timely payment is not received, Wells Fargo Bank's automated loan servicing system automatically places the Mortgage Loan in the assigned collection queue and collection procedures are generally initiated on the 16th day of delinquency. The account remains in the queue unless and until a payment is received, at which point Wells Fargo Bank's automated loan servicing system automatically removes the Mortgage Loan from that collection queue.

When a Mortgage Loan appears in a collection queue, a collector will telephone to remind the borrower that a payment is due. Follow-up telephone contacts with the borrower are attempted until the account is current or other payment arrangements have been made. When contact is made with a delinquent borrower, collectors present such borrower with alternative payment methods, such as Western Union, Phone Pay and Quick Collect, in order to expedite payments. Standard form letters are utilized when attempts to reach the borrower by telephone fail and/or in some circumstances, to supplement the phone contacts. Company collectors have computer access to telephone numbers, payment histories, loan information and all past collection notes. Wells Fargo Bank supplements the collectors' efforts with advanced technology such as predictive dialers and statistical behavioral software used to determine the optimal times to call a particular customer. Additionally, collectors may attempt to mitigate losses through the use of behavioral or other models that are designed to assist in identifying workout options in the early stages of delinquency. For those loans in which collection efforts have been exhausted without success, Wells Fargo Bank determines whether foreclosure proceedings are appropriate. The course of action elected with respect to a delinquent Mortgage Loan generally will be guided by a number of factors, including the related borrower's payment history, ability and willingness to pay, the condition and occupancy of the Mortgaged Property, the amount of borrower equity in the Mortgaged Property and whether there are any junior liens.

Regulations and practices regarding the liquidation of properties (e.g., foreclosure) and the rights of a borrower in default vary greatly from state to state. As such, all foreclosures are assigned to outside counsel, licensed to practice in the same state as the Mortgaged Property. Bankruptcies filed by borrowers are similarly assigned to appropriate local counsel. Communication with foreclosure and bankruptcy attorneys is maintained through the use of a software program, thus reducing the need for phone calls and faxes and simultaneously creating a permanent record of communication. Attorney timeline performance is managed using quarterly report cards. The status of foreclosures and bankruptcies is monitored by Wells Fargo Bank through its use of such software system. Bankruptcy filing and release information is received electronically from a third-party notification vendor.

Prior to a foreclosure sale, Wells Fargo Bank performs a market value analysis. This analysis includes: (i) a current valuation of the Mortgaged Property obtained through a drive-by appraisal or broker's price opinion conducted by an independent appraiser and/or a broker from a network of real estate brokers, complete with a description of the condition of the Mortgaged Property, as well as other information such as recent price lists of comparable properties, recent closed comparables, estimated marketing time and required or suggested repairs, and an estimate of the sales price; (ii) an evaluation of the amount owed, if any, for real estate taxes; and (iii) estimated carrying costs, brokers' fees, repair costs and other related costs associated with real estate owned properties. Wells Fargo Bank bases the amount it will bid at foreclosure sales on this analysis.

If Wells Fargo Bank acquires title to a property at a foreclosure sale or otherwise, it obtains an estimate of the sale price of the property and then hires one or more real estate brokers to begin marketing the property. If the Mortgaged Property is not vacant when acquired, local eviction attorneys are hired to commence eviction proceedings and/or negotiations are held with occupants in an attempt to get them to vacate without incurring the additional time and cost of eviction. Repairs are performed if it is determined that they will increase the net

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liquidation proceeds, taking into consideration the cost of repairs, the carrying costs during the repair period and the marketability of the property both before and after the repairs.

Wells Fargo Bank's loan servicing software also tracks and maintains tax and homeowners' insurance information and tax and insurance escrow information. Expiration reports are generated periodically listing all policies scheduled to expire. When policies lapse, a letter is automatically generated and issued advising the borrower of such lapse and notifying the borrower that Wells Fargo Bank will obtain lender-placed insurance at the borrower's expense.

Any material changes from the servicing policies and procedures of Wells Fargo Bank set forth herein will be described in the applicable prospectus supplement.

Payments on Mortgage Loans

The Master Servicer will, as to each Series of Certificates, establish and maintain a separate trust account in the name of the Master Servicer on behalf of the Trustee (the "Certificate Account"). Such account may be established at Wells Fargo Bank or an affiliate thereof. Each such account must be maintained with a depository institution ("Depository") either (i) whose long-term debt obligations (or, in the case of a depository institution which is part of a holding company structure, the long-term debt obligations of such parent holding company) are, at the time of any deposit therein rated in at least one of the two highest rating categories by each nationally recognized statistical rating organization that rated the related Series of Certificates, (ii) that is a federal or state charted depository institution or trust company acting in its fiduciary capacity with respect to such accounts which shall be trust accounts maintained with its trust department, or (iii) that is otherwise acceptable to the Rating Agency or Rating Agencies rating the Certificates of such Series and, if a REMIC election has been made, that would not cause the related Trust Estate (or one or more segregated pools of assets therein) to fail to qualify as a REMIC. To the extent that the portion of funds deposited in the Certificate Account at any time exceeds the limit of insurance coverage established by the Federal Deposit Insurance Corporation (the "FDIC"), such excess will be subject to loss in the event of the failure of the Depository. Such insurance coverage will be based on the number of holders of Certificates, rather than the number of underlying mortgagors. Holders of the Subordinated Certificates of a Series will bear any such loss up to the amount of principal payments on the related Mortgage Loans to which such holders are entitled.

Pursuant to the applicable Underlying Servicing Agreements with respect to a Series, each Servicer may be required to establish and maintain one or more accounts (collectively, the "Servicer Custodial Account") into which the Servicer will be required to deposit on a daily basis amounts received with respect to Mortgage Loans serviced by such Servicer included in the Trust Estate for such Series, as more fully described below. Each required Servicer Custodial Account must generally be a separate custodial account insured to the available limits by the FDIC or otherwise acceptable to the applicable Rating Agencies (such eligible account, an "Eligible Custodial Account") and limited to funds held with respect to a particular Series, unless the Underlying Servicing Agreement specifies that a Servicer may establish an account which is an eligible account to serve as a unitary Servicer Custodial Account both for such Series and for other Series of Certificates for which Wells Fargo Bank is the Master Servicer and having the same financial institution acting as Trustee and to be maintained in the name of such financial institution, in its respective capacities as Trustee for each such Series. Notwithstanding the foregoing, Wells Fargo Bank will be permitted to commingle funds in its Servicer Custodial Account with its general assets until such time as such funds are required to be remitted to the Certificate Account for so long as (i) a master guarantee of Wells Fargo Bank's remittance obligation has been issued by its parent, Wells Fargo & Company ("Wells Fargo") for the benefit of the Certificateholders and is currently in force and (ii) the short-term debt or long-term debt of Wells Fargo is rated by the Rating Agencies in their highest short-term or highest long-term category or in such lower rating category that would not result in a downgrading or withdrawal of the rating then assigned to any Class of Certificates by the Rating Agencies or result in any rated Class of Certificates being placed on credit review status by the Rating Agencies.

The "Remittance Date" with respect to any Distribution Date generally will be
(i) for any Mortgage Loan serviced by a Servicer other than Wells Fargo Bank, the 18th day of each month, or if any such day is not a business day, the preceding business day and (ii) for any Mortgage Loan serviced by Wells Fargo Bank, the 24th day of each month, or if any such day is not a business day, the preceding business day.

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Each Servicer will be required to deposit in the Certificate Account for each Series of Certificates backed by Mortgage Loans on the first Remittance Date any amounts representing scheduled payments of principal and interest on the Mortgage Loans serviced by such Servicer due after the applicable Cut-Off Date but received on or prior thereto, and will deposit in the Servicer Custodial Account on receipt and on the Remittance Date will remit to the Master Servicer for deposit in the Certificate Account, the following payments and collections received or made by such Servicer with respect to the Mortgage Loans serviced by such Servicer subsequent to the applicable Cut-Off Date (other than (a) payments due on or before the Cut-Off Date, (b) amounts held for future distribution, (c) amounts representing certain expenses reimbursable to the Servicer, (d) amounts representing reimbursements for Periodic Advances made by the Servicer, (e) amounts representing additional servicing compensation and (f) any other amounts permitted to be retained by the Servicer pursuant to the applicable Underlying Servicing Agreement):

(i) all payments on account of principal, including prepayments, and interest;

(ii) all Liquidation Proceeds less, to the extent permitted under the applicable Underlying Servicing Agreement, the amount of any expenses incurred in connection with the liquidation of such Mortgage Loans;

(iii) all proceeds received by the Servicer under any title, hazard or other insurance policy covering any such Mortgage Loan, other than proceeds to be applied to the restoration or repair of the property subject to the related Mortgage or released to the mortgagor in accordance with the Underlying Servicing Agreement;

(iv) all Periodic Advances made by the Servicer;

(v) all amounts withdrawn from Buy-Down Funds or Subsidy Funds, if any, with respect to such Mortgage Loans, in accordance with the terms of the respective agreements applicable thereto;

(vi) all proceeds of any such Mortgage Loans or property acquired in respect thereof purchased or repurchased pursuant to the Pooling and Servicing Agreement or the Underlying Servicing Agreement; and

(vii) all other amounts required to be deposited therein pursuant to the applicable Pooling and Servicing Agreement or the Underlying Servicing Agreement.

Notwithstanding the foregoing, if at any time the sums in (x) any Servicer Custodial Account, other than any Eligible Custodial Account, exceed $100,000 or
(y) any such Servicer Custodial Account, in certain circumstances, exceed such amount less than $100,000 as shall have been specified by the Master Servicer, the Servicer will be required within one business day to withdraw such excess funds from such account and remit such amounts to the Certificate Account.

Notwithstanding the foregoing, each Servicer will be entitled, at its election, either (a) to withhold and pay itself the applicable Servicing Fee from any payment or other recovery on account of interest as received and prior to deposit in the Servicer Custodial Account or (b) to withdraw from the Servicer Custodial Account the applicable Servicing Fee after the entire payment or recovery has been deposited in such account.

The Master Servicer or Trustee will deposit in the Certificate Account any Periodic Advances made by the Master Servicer or Trustee in the event of a Servicer default or as otherwise required by the Pooling and Servicing Agreement not later than the Distribution Date on which such amounts are required to be distributed. All other amounts will be deposited in the Certificate Account not later than the business day next following the day of receipt and posting by the Master Servicer. On or prior to each Distribution Date, the Master Servicer will cause to be deposited into the Payment Account for distribution by the Paying Agent to Certificateholders all amounts allocable to the Pool Distribution Amount for such Distribution Date.

If a Servicer, the Master Servicer or the Trustee deposits in the Certificate Account for a Series any amount not required to be deposited therein, the Master Servicer may at any time withdraw such amount from such account for itself or for remittance to such Servicer or the Trustee, as applicable. Funds on deposit in the Certificate Account may be invested in certain investments acceptable to the Rating Agencies ("Eligible Investments") maturing in general not later than the business day preceding the next Distribution Date. In the event that an election has been made to treat the Trust Estate (or one or more segregated pools of assets therein) with respect to a Series as a

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REMIC, no such Eligible Investments will be sold or disposed of at a gain prior to maturity unless the Master Servicer has received an opinion of counsel or other evidence satisfactory to it that such sale or disposition will not cause the Trust Estate (or segregated pool of assets) to be subject to the tax on "prohibited transactions" imposed by Code Section 860F(a)(1), otherwise subject the Trust Estate (or segregated pool of assets) to tax, or cause the Trust Estate (or any segregated pool of assets) to fail to qualify as a REMIC while any Certificates of the Series are outstanding. Except as otherwise specified in the applicable prospectus supplement, all income and gain realized from any such investment will be for the account of the Master Servicer as additional compensation and all losses from any such investment will be deposited by the Master Servicer out of its own funds to the Certificate Account immediately as realized.

The Master Servicer is permitted, from time to time, to make withdrawals from the Certificate Account for the following purposes, to the extent permitted in the applicable Pooling and Servicing Agreement (and, in the case of Servicer reimbursements by the Master Servicer, only to the extent funds in the respective Servicer Custodial Account are not sufficient therefor):

(i) to reimburse the Master Servicer, the Trustee or any Servicer for Advances;

(ii) to reimburse any Servicer for liquidation expenses and for amounts expended by itself or any Servicer, as applicable, in connection with the restoration of damaged property;

(iii) to pay to itself the applicable Master Servicing Fee and any other amounts constituting additional master servicing compensation, to pay any other fees described in the applicable prospectus supplement; and to pay to the owner thereof any Fixed Retained Yield;

(iv) to reimburse itself, any Servicer or the Trustee (or, in certain cases, the Depositor) for certain expenses (including amounts as to which a Servicer is entitled to reimbursement for taxes paid on behalf of the Trust Estate) or indemnities incurred by and recoverable by or reimbursable to itself, any Servicer or the Trustee, as applicable, or any reimbursement amounts owed to itself, any Servicer or the Trustee, as applicable;

(v) to pay to the Depositor, a Servicer or itself with respect to each Mortgage Loan or property acquired in respect thereof that has been repurchased by the Depositor or purchased by a Servicer or the Master Servicer all amounts received thereon and not distributed as of the date as of which the purchase price of such Mortgage Loan was determined;

(vi) to pay to itself any interest earned on or investment income earned with respect to funds in the Certificate Account (all such interest or income to be withdrawn not later than the next Distribution Date);

(vii) to pay to itself, the Servicer and the Trustee from net Liquidation Proceeds allocable to interest, the amount of any unpaid Master Servicing Fee or Servicing Fees and any unpaid assumption fees, late payment charges or other mortgagor charges on the related Mortgage Loan;

(viii) to remit funds to the Paying Agent;

(ix) to withdraw from the Certificate Account any amount deposited in such account that was not required to be deposited therein; and

(x) to clear and terminate the Certificate Account.

A paying agent (the "Paying Agent"), which may be the Master Servicer or the Trustee, will be appointed pursuant to the Pooling and Servicing Agreement to make distributions to Certificateholders of a Series. The Trustee may remove or replace the Paying Agent, other than Wells Fargo Bank, for so long as Wells Fargo Bank is acting as the Master Servicer. Wells Fargo Bank, as Master Servicer, will, on or prior to each Distribution Date, deposit in immediately available funds in an account designated by the Paying Agent, which may be the Certificate Account if Wells Fargo Bank is also acting as Paying Agent (the "Payment Account"), the amount required to be distributed to the Certificateholders on such Distribution Date. Funds on deposit in the Payment Account may be invested in Eligible Investments, as directed by the Master Servicer. All income and gain realized from any such investment will be for the account of the Master Servicer or such other party identified in the applicable prospectus supplement

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as additional compensation and all losses from any such investment will be deposited by such party out of its own funds to the Payment Account immediately as realized. Any fee payable to the Paying Agent will be paid by the Master Servicer.

The Trustee will cause any Paying Agent that is not the Trustee or the Master Servicer to execute and deliver to the Trustee an instrument in which such Paying Agent agrees with the Trustee that such Paying Agent will:

(i) hold all amounts deposited with it by the Master Servicer for distribution to Certificateholders in trust for the benefit of Certificateholders until such amounts are distributed to Certificateholders or otherwise disposed of as provided in the Pooling and Servicing Agreement;

(ii) give the Trustee notice of any default by the Master Servicer in remitting any required amount;

(iii) at any time during the continuance of any such default, upon written request to the Trustee, forthwith pay to the Trustee all amounts held in trust by such Paying Agent; and

(iv) if necessary in order to comply with the requirements of Regulation AB (17 C.F.R. 229), provide to the Depositor and the Master Servicer the assessment of compliance by such entity with the servicing criteria set forth in Item 1122(d) of Regulation AB (17 C.F.R. 229.1122) applicable to its duties and the related attestation reports.

Periodic Advances and Limitations Thereon

Generally each Servicer will be required to make (i) advances to cover delinquent payments of principal and interest (a "Periodic Advance") on such Mortgage Loan and (ii) other advances of cash ("Other Advances" and, collectively with Periodic Advances, "Advances") to cover(w) delinquent payments of taxes, insurance premiums, and other escrowed items, (x) credit counseling fees, (y) rehabilitation expenses and foreclosure costs, including reasonable attorneys' fees and (z) other customary costs and expenses incurred by the Servicer in the performance of its obligations, in either case unless such Servicer has determined that any subsequent payments on that Mortgage Loan or from the borrower will ultimately not be available to reimburse such Servicer for such amounts. The failure of the Servicer to make any required Periodic Advances or Other Advances under an Underlying Servicing Agreement constitutes a default under such agreement for which the Servicer will be terminated. Upon default by a Servicer, other than Wells Fargo Bank as a Servicer, the Master Servicer may, and upon default by Wells Fargo Bank, the Trustee may, be required to make Periodic Advances to the extent necessary to make required distributions on certain Certificates or certain Other Advances, provided that the Master Servicer or Trustee, as applicable, determines that funds will ultimately be available to reimburse it. In the case of Certificates of any Series for which credit enhancement is provided in the form of a mortgage pool insurance policy, the Depositor may obtain an endorsement to the mortgage pool insurance policy which obligates the pool insurer to advance delinquent payments of principal and interest. The pool insurer would only be obligated under such endorsement to the extent the mortgagor fails to make such payment and the Master Servicer or Trustee fails to make a required advance.

Any such Periodic Advances by the Servicers or the Master Servicer or Trustee, as the case may be, must be deposited into the applicable Servicer Custodial Account or the Certificate Account and will be due no later than the business day before the Distribution Date to which such delinquent payment relates. Advances by the Servicers or the Master Servicer or Trustee, as the case may be, will be reimbursable out of insurance proceeds or Liquidation Proceeds of, or, except for Other Advances, future payments on, the Mortgage Loans for which such amounts were advanced. If an Advance made by a Servicer, the Master Servicer or the Trustee later proves, or is deemed by the Master Servicer or the Trustee, to be unrecoverable, such Servicer, the Master Servicer or the Trustee, as the case may be, will be entitled to reimbursement from funds in the Certificate Account prior to the distribution of payments to the Certificateholders in accordance with the Pooling and Servicing Agreement.

Any Periodic Advances made by a Servicer, the Master Servicer or the Trustee with respect to Mortgage Loans included in the Trust Estate for any Series are intended to enable the Paying Agent to make timely payment of the scheduled distributions of principal and interest on the Certificates of such Series. However, neither the Master Servicer, the Trustee, the Paying Agent, any Servicer nor any other person will, except as otherwise specified in the applicable prospectus supplement, insure or guarantee the Certificates of a Series or the Mortgage Loans included in the related Trust Estate for any Certificates.

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PMI Advances

If a Servicer has recovered all Liquidation Proceeds with respect to a Mortgage Loan other than amounts it expects to receive from a primary mortgage insurer, the Servicer may, if the applicable Underlying Servicing Agreement so provides, advance the amount expected to be received from the primary mortgage insurer (a "PMI Advance"). If a PMI Advance is made, the Mortgage Loan will be considered a Liquidated Loan and the PMI Advance will be considered a part of the Liquidation Proceeds. The Servicer will be entitled to reimbursement for the PMI Advance from the amounts received from the primary mortgage insurer. In the event that the amount received from the primary mortgage insurer is less than the related PMI Advance, the Servicer will be entitled to recover the amount of the unreimbursed PMI Advance from any other funds on deposit in the applicable Servicer Custodial Account.

Collection and Other Servicing Obligations

Each Servicer will be required by the related Underlying Servicing Agreement to make reasonable efforts to collect all payments called for under the Mortgage Loans and, consistent with the applicable Underlying Servicing Agreement and any applicable agreement governing any form of credit enhancement, to follow such collection procedures as it follows with respect to mortgage loans serviced by it that are comparable to the Mortgage Loans. Consistent with the above, the Servicer may, in its discretion, (i) waive any prepayment charge, assumption fee, late payment charge or any other charge in connection with the prepayment of a Mortgage Loan and (ii) arrange with a mortgagor a schedule for the liquidation of deficiencies running for a period conforming to acceptable servicing practices (or such shorter period, if any, provided by the Underlying Servicing Agreement).

Under each Underlying Servicing Agreement, each Servicer, to the extent permitted by law, will establish and maintain one or more escrow accounts (each such account, a "Servicing Account") in which each such Servicer will be required to deposit any payments made by mortgagors in advance for taxes, assessments, primary mortgage (if applicable) and hazard insurance premiums and other similar items. Withdrawals from the Servicing Account may be made to effect timely payment of taxes, assessments, mortgage and hazard insurance, to refund to mortgagors amounts determined to be overages, to pay interest to mortgagors on balances in the Servicing Account, if required, and to clear and terminate such account. Each Servicer will be responsible for the administration of its Servicing Account. A Servicer will be obligated to advance certain amounts which are not timely paid by the mortgagors, to the extent that it determines, in good faith, that they will be recoverable out of insurance proceeds, liquidation proceeds, or otherwise. Alternatively, in lieu of establishing a Servicing Account, a Servicer may procure a performance bond or other form of insurance coverage, in an amount acceptable to the Master Servicer and each Rating Agency rating the related Series of Certificates, covering loss occasioned by the failure to escrow such amounts.

Enforcement of Due-on-Sale Clauses; Realization Upon Defaulted Mortgage Loans

With respect to each Mortgage Loan, the applicable Underlying Servicing Agreement will generally provide that, when any Mortgaged Property is about to be conveyed by the mortgagor, the Servicer will, to the extent it has knowledge of such prospective conveyance, exercise its rights to accelerate the maturity of such Mortgage Loan under the "due-on-sale" clause applicable thereto, if any, unless (i) such exercise is not permissible under applicable law; (ii) such exercise would result in loss of insurance coverage with respect to such Mortgage Loan or, in the case of a Servicer other than Wells Fargo Bank, would, in the Servicer's judgment, be reasonably likely to result in litigation by the mortgagor and such Servicer has not obtained the Master Servicer's consent to such exercise; or (iii) in the case of a Mortgage Loan having an adjustable interest rate, (a) the mortgagor causes to be submitted to the Servicer information required by the Servicer to evaluate the intended transferee as if a new loan were being made to the transferee; and (b) the Servicer reasonably determines that the Servicer's security will not be impaired by the loan assumption and that the risk of a breach of any covenant or agreement in the Mortgage Note or the Mortgage is acceptable to the Servicer. In any case, the Servicer is authorized to take or enter into an assumption and modification agreement from or with the person to whom such Mortgaged Property has been or is about to be conveyed, pursuant to which such person becomes liable under the Mortgage Note and, unless prohibited by applicable state law, the mortgagor remains liable thereon, provided that the Mortgage Loan will continue to be covered by any pool insurance policy and any related primary mortgage insurance policy and the Mortgage Interest Rate with respect to such Mortgage Loan and the payment terms shall remain unchanged. The Servicer will also be

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authorized, with the prior approval of the pool insurer and the primary mortgage insurer, if any, to enter into a substitution of liability agreement with such person, pursuant to which the original mortgagor is released from liability and such person is substituted as mortgagor and becomes liable under the Mortgage Note.

Each Underlying Servicing Agreement and Pooling and Servicing Agreement with respect to a Series backed by Mortgage Loans will require the Servicer or the Master Servicer, as the case may be, to present claims to the insurer under any insurance policy applicable to the Mortgage Loans included in the Trust Estate for such Series and to take such reasonable steps as are necessary to permit recovery under such insurance policies with respect to defaulted Mortgage Loans, or losses on the Mortgaged Property securing the Mortgage Loans.

Each Servicer is obligated under the applicable Underlying Servicing Agreement for each Series backed by Mortgage Loans to realize upon defaulted Mortgage Loans in accordance with its normal servicing practices, which will conform generally to those of prudent mortgage lending institutions which service mortgage loans of the same type in the same jurisdictions. The Servicer may exercise its discretion to enter into forbearance arrangements with borrowers for specified time periods, however, during such time periods the Servicer will report the related mortgage loan to be in a delinquent status. In addition, the Servicer is authorized under the applicable Underlying Servicing Agreement to permit the assumption of a defaulted Mortgage Loan rather than to foreclose or accept a deed-in-lieu of foreclosure if, in the Servicer's judgment, the default is unlikely to be cured and the assuming borrower meets Wells Fargo Bank's applicable underwriting guidelines. In connection with any such assumption, the Mortgage Interest Rate and the payment terms of the related Mortgage Note will not be changed. Each Servicer may also waive, modify or vary any term of a Mortgage Loan or consent to the postponement of strict compliance with any term or in any manner grant indulgence to a mortgagor. However, unless a Mortgage Loan is in default or, in the judgment of the Servicer, default is reasonably foreseeable and the Servicer determines such waiver, modification, postponement or indulgence is not materially adverse to Certificateholders in the aggregate, the Servicer will not change the Mortgage Interest Rate, defer or forgive the payment thereof of any principal or interest payments, reduce or increase the outstanding principal amount (except for actual payments of principal) or extend the final maturity date of such Mortgage Loan. If a Mortgage Loan is in default or default is reasonably foreseeable, the final maturity date of such Mortgage Loan may be extended but not beyond the final scheduled distribution date as set forth in the applicable prospectus supplement for the related Classes of Certificates. Any modification will be deemed to not materially adversely affect Certificateholders in the aggregate if the Servicer has reasonably determined that such modification is likely to increase the proceeds of such Mortgage Loan over the amount expected to be collected pursuant to foreclosure. A Servicer may permit the capitalization of unreimbursed Periodic Advances and the amount of any unreimbursed Other Advances previously made by the Servicer in connection with a Servicer Modification of a Mortgage Loan. A Servicer will be entitled to retain the portions of any modified monthly payment subsequently made by the borrower which represent (i) the amount so capitalized together with interest thereon and (ii) the principal portion of Periodic Advances unreimbursed to the Servicer as of the date of the Servicer Modification, together with interest thereon. In the event of a subsequent uncured default by the borrower under the related modification agreement, the Servicer will be entitled to recover, from Liquidation Proceeds on the related Mortgage Loan, the amount of all its Periodic Advances and/or Other Advances, including those that were capitalized at the time of the Servicer Modification, without interest on such advances except to the extent previously paid by the borrower. See also "The Pooling and Servicing Agreement--Optional Purchases," below, with respect to the Depositor's right to repurchase Mortgage Loans that are in default. Further, a Servicer may encourage selling a Mortgaged Property securing a defaulted Mortgage Loan for less than the unpaid principal balance of such Mortgage Loan. In connection with the decision of the Servicer regarding the foreclosure or assumption of a Mortgage Loan, the modification of the related Mortgage Note or any other action to be taken with respect to a defaulted Mortgage Loan, the Servicer is expressly permitted by the Underlying Servicing Agreement to take into account the interests of the borrower. The Servicer may also make other modifications if an opinion of counsel is delivered to the Trustee to the effect that such modification will not give rise to a new debt instrument for federal income tax purposes. However, no opinion is required to be delivered in connection with the reamortization of a Mortgage Loan over the remaining original term after the outstanding principal balance of the Mortgage Loan has been reduced by a Curtailment.

In the case of foreclosure or of damage to a Mortgaged Property from an uninsured cause, the Servicer will not be required to expend its own funds to foreclose or restore any damaged property, unless it reasonably determines (i) that such foreclosure or restoration will increase the proceeds to Certificateholders of such Series of liquidation of the Mortgage Loan after reimbursement to the related Servicer for its expenses and (ii) that such expenses will be

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recoverable to it through Liquidation Proceeds or any applicable insurance policy in respect of such Mortgage Loan. In the event that Servicer has expended its own funds for foreclosure or to restore damaged property, it will be entitled to be reimbursed from the Certificate Account for such Series an amount equal to all costs and expenses incurred by it.

Wells Fargo Bank as a Servicer will not be obligated to, and any other Servicer will not (except with the express written approval of the Master Servicer), foreclose on any Mortgaged Property which it believes may be contaminated with or affected by hazardous wastes or hazardous substances. See "Certain Legal Aspects of the Mortgage Loans--Environmental Considerations." If a Servicer does not foreclose on a Mortgaged Property, the Certificateholders of the related Series may experience a loss on the related Mortgage Loan. A Servicer will not be liable to the Certificateholders if it fails to foreclose on a Mortgaged Property which it believes may be so contaminated or affected, even if such Mortgaged Property is, in fact, not so contaminated or affected. Conversely, a Servicer will not be liable to the Certificateholders if, based on its belief that no such contamination or effect exists, the Servicer forecloses on a Mortgaged Property and takes title to such Mortgaged Property, and thereafter such Mortgaged Property is determined to be so contaminated or affected.

The Servicer may foreclose against property securing a defaulted Mortgage Loan either by foreclosure, by sale or by strict foreclosure and in the event a deficiency judgment is available against the mortgagor or other person (see "Certain Legal Aspects of the Mortgage Loans--Anti-Deficiency Legislation and Other Limitations on Lenders" for a discussion of the availability of deficiency judgments), may proceed for the deficiency. It is anticipated that in most cases the Servicer will not seek deficiency judgments, and will not be required under the applicable Underlying Servicing Agreement to seek deficiency judgments. In lieu of foreclosure, each Servicer may arrange for the sale by the borrower of the Mortgaged Property related to a defaulted Mortgage Loan to a third party, rather than foreclosing upon and selling such Mortgaged Property.

With respect to a Trust Estate (or any segregated pool of assets therein) as to which a REMIC election has been made, if the Trustee acquires ownership of any Mortgaged Property as a result of a default or reasonably foreseeable default of any Mortgage Loan secured by such Mortgaged Property, the Trustee (or Servicer acting on behalf of the Trustee) or Master Servicer will be required to dispose of such property prior to the close of the third calendar year following the year the Trust Estate acquired such property (or such shorter period if provided in the applicable Underlying Servicing Agreement) unless the Trustee
(a) receives an opinion of counsel to the effect that the holding of the Mortgaged Property by the Trust Estate will not cause the Trust Estate to be subject to the tax on "prohibited transactions" imposed by Code Section 860F(a)(1) or cause the Trust Estate (or any segregated pool of assets therein as to which one or more REMIC elections have been made or will be made) to fail to qualify as a REMIC or (b) applies for and is granted an extension of the applicable period in the manner contemplated by Code Section 856(e)(3). The Servicer also will be required to administer the Mortgaged Property in a manner which does not cause the Mortgaged Property to fail to qualify as "foreclosure property" within the meaning of Code Section 860G(a)(8) or result in the receipt by the Trust Estate of any "net income from foreclosure property" within the meaning of Code Section 860G(c)(2), respectively. In general, this would preclude the holding of the Mortgaged Property by a party acting as a dealer in such property or the receipt of rental income based on the profits of the lessee of such property. See "Material Federal Income Tax Consequences."

Insurance Policies

Standard Hazard Insurance Policies

Each Underlying Servicing Agreement will require the related Servicer to cause to be maintained for each Mortgage Loan a standard hazard insurance policy issued by a generally acceptable insurer insuring the improvements on the Mortgaged Property underlying such Mortgage Loan against loss by fire, with extended coverage (a "Standard Hazard Insurance Policy"). The Underlying Servicing Agreements will require that such Standard Hazard Insurance Policy be in an amount at least equal to the lesser of 100% of the insurable value of the improvements on the Mortgaged Property or the unpaid principal balance of such Mortgage Loan; provided, however, that such insurance may not be less than the minimum amount required to fully compensate for any damage or loss on a replacement cost basis. Each Servicer will also maintain on property acquired upon foreclosure, or deed in lieu of foreclosure, of any Mortgage Loan, a Standard Hazard Insurance Policy in an amount that is at least equal to the lesser of 100% of the insurable value of the improvements which are a part of such property or the

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principal balance of such Mortgage Loan plus accrued interest and liquidation expenses; provided, however, that such insurance may not be less than the minimum amount required to fully compensate for any damage or loss on a replacement cost basis. Any amounts collected under any such policies (other than amounts to be applied to the restoration or repair of the Mortgaged Property or released to the borrower in accordance with normal servicing procedures) will be deposited in the Servicer Custodial Account for remittance to the Certificate Account by a Servicer.

The Standard Hazard Insurance Policies covering the Mortgage Loans generally will cover physical damage to, or destruction of, the improvements on the Mortgaged Property caused by fire, lightning, explosion, smoke, windstorm, hail, riot, strike and civil commotion, subject to the conditions and exclusions particularized in each policy. Because the Standard Hazard Insurance Policies relating to such Mortgage Loans will be underwritten by different insurers and will cover Mortgaged Properties located in various states, such policies will not contain identical terms and conditions. The most significant terms thereof, however, generally will be determined by state law and generally will be similar. Most such policies typically will not cover any physical damage resulting from the following: war, revolution, governmental actions, floods and other water-related causes, earth movement (including earthquakes, landslides and mudflows), nuclear reaction, wet or dry rot, vermin, rodents, insects or domestic animals, hazardous wastes or hazardous substances, theft and, in certain cases, vandalism. The foregoing list is merely indicative of certain kinds of uninsured risks and is not all-inclusive.

In general, if the improvements on a Mortgaged Property are located in an area identified in the Federal Register by the Federal Emergency Management Agency as having special flood hazards (and such flood insurance has been made available) each Underlying Servicing Agreement will require the related Servicer to cause to be maintained a flood insurance policy meeting the requirements of the current guidelines of the Federal Insurance Administration with a generally acceptable insurance carrier. Generally, the Underlying Servicing Agreement will require that such flood insurance be in an amount not less than the least of (i) the outstanding principal balance of the Mortgage Loan, (ii) the full insurable value of the improvements, or (iii) the maximum amount of insurance which is available under the National Flood Insurance Program's regular program or its emergency program. Wells Fargo Bank does not provide financing for flood zone properties located in communities not participating in the National Flood Insurance Program or if available insurance coverage is, in its judgment, unrealistically low.

Wells Fargo Bank will not require that a standard hazard or flood insurance policy be maintained on the cooperative dwelling relating to any cooperative loan. Generally, the Cooperative itself is responsible for maintenance of hazard insurance for the property owned by the Cooperative and the tenant-stockholders of that Cooperative do not maintain individual hazard insurance policies. To the extent, however, that a Cooperative and the related borrower on a Mortgage Loan that is a cooperative loan do not maintain such insurance or do not maintain adequate coverage or any insurance proceeds are not applied to the restoration of damaged property, any damage to such borrower's cooperative dwelling or such Cooperative's building could significantly reduce the value of the collateral securing such Mortgage Loan that is a cooperative loan to the extent not covered by other credit support.

Each Servicer may maintain a lender-placed policy insuring against hazard losses on all of the Mortgaged Properties in lieu of maintaining the required Standard Hazard Insurance Policies and may maintain a lender-placed policy insuring against special hazards in lieu of maintaining any required flood insurance. Each Servicer will be liable for the amount of any deductible under a lender-placed policy if such amount would have been covered by a required Standard Hazard Insurance Policy or flood insurance, had it been maintained.

Any losses incurred with respect to Mortgage Loans due to uninsured risks (including earthquakes, mudflows, floods and hazardous wastes or hazardous substances) or insufficient hazard insurance proceeds will adversely affect distributions to the Certificateholders.

Primary Mortgage Insurance Policies

If so specified in the applicable Prospectus Supplement, the Servicer will maintain or cause to be maintained, as the case may be, in full force and effect, a primary mortgage insurance policy with regard to each Mortgage Loan for which such coverage is required. Primary mortgage insurance policies reimburse certain losses sustained by reason of defaults in payments by borrowers. The Servicer will not cancel or refuse to renew any such primary mortgage insurance policy in effect at the time of the initial issuance of a Series of Certificates that is required to be kept in force under the applicable Underlying Servicing Agreement unless the replacement primary mortgage

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insurance policy for such cancelled or nonrenewed policy is maintained with an insurer whose claims-paying ability is sufficient to maintain the current rating of the classes of Certificates of such Series that have been rated.

Fixed Retained Yield, Servicing Compensation and Payment of Expenses

Fixed Retained Yield with respect to any Mortgage Loan is that portion, if any, of interest at the Mortgage Interest Rate as of the Cut-off Date that is not included in the related Trust Estate. The prospectus supplement for a Series backed by Mortgage Loans will specify if there is any Fixed Retained Yield with respect to the Mortgage Loans of such Series. If so, the Fixed Retained Yield will be established on a loan-by-loan basis and will be specified in the schedule of Mortgage Loans delivered to the applicable Trustee or custodian. Wells Fargo Bank as Servicer may deduct the Fixed Retained Yield from mortgagor payments as received or deposit such payments in the Servicer Custodial Account or the Certificate Account for such Series and then either withdraw the Fixed Retained Yield from the Servicer Custodial Account or the Certificate Account. In the case of any Fixed Retained Yield with respect to Mortgage Loans serviced by a Servicer other than Wells Fargo Bank, the Master Servicer will make withdrawals from the Certificate Account for the purpose of remittances to Wells Fargo Bank as owner of the Fixed Retained Yield.

For each Series of Certificates issued by a Trust containing Mortgage Loans, each Servicer will be entitled to be paid the Servicing Fee on the related Mortgage Loans serviced by such Servicer until termination of the applicable Underlying Servicing Agreement. A Servicer, at its election, will pay itself the Servicing Fee for such Series with respect to each Mortgage Loan by (a) withholding the Servicing Fee from any scheduled payment of interest prior to deposit of such payment in the Servicer Custodial Account for such Series or (b) withdrawing the Servicing Fee from the Servicer Custodial Account after the entire interest payment has been deposited in such account. A Servicer may also pay itself out of the Liquidation Proceeds of a Mortgage Loan or other recoveries with respect thereto, or withdraw from the Servicer Custodial Account or request the Master Servicer to withdraw from the Certificate Account for remittance to the Servicer such amounts after the deposit thereof in such accounts, the Servicing Fee in respect of such Mortgage Loan as provided in the applicable Pooling and Servicing Agreement. The Servicing Fee or the range of Servicing Fees with respect to the Mortgage Loans underlying the Certificates of such Series will be specified in the applicable prospectus supplement. Additional servicing compensation in the form of prepayment charges, assumption fees, late payment charges or Liquidation Profits or otherwise will be retained by the Servicers, to the extent specified in the Underlying Servicing Agreement.

Generally, each Servicer will pay all expenses incurred in connection with the servicing of the Mortgage Loans serviced by such Servicer underlying a Series, including, without limitation, payment of the hazard insurance policy premiums. The Servicers will be entitled, in certain circumstances, to reimbursement from the Certificate Account of Periodic Advances, of Other Advances made by it to pay taxes, insurance premiums and similar items with respect to any Mortgaged Property, for expenditures incurred by it in connection with the restoration, foreclosure or liquidation of any Mortgaged Property (to the extent of Liquidation Proceeds or insurance policy proceeds in respect of such Mortgaged Property) or for certain property inspection expenses for defaulted Mortgage Loans or Mortgaged Properties owned by the Trust and of certain losses against which it is indemnified by the Trust Estate.

As set forth in the preceding paragraph, a Servicer may be entitled to reimbursement for certain expenses incurred by it, and payment of additional fees for certain extraordinary services rendered by it (provided that such fees do not exceed those which would be charged by third parties for similar services) in connection with the liquidation of defaulted Mortgage Loans and related Mortgaged Properties. In the event that claims are either not made or are not fully paid from any applicable form of credit enhancement, the related Trust Estate will suffer a loss to the extent that Liquidation Proceeds, after reimbursement of the Servicing Fee and the expenses of the Servicer, are less than the principal balance of the related Mortgage Loan.

Evidence as to Compliance

Each Servicer and the Master Servicer will deliver or make available annually, on or before the date specified in the applicable Underlying Servicing Agreement or Pooling and Servicing Agreement, as applicable, an officer's certificate stating that (i) a review of the activities of the Master Servicer or such Servicer during the preceding calendar year and of performance under the applicable Pooling and Servicing Agreement or Underlying Servicing Agreement has been made under the supervision of such officer, and (ii) to the best of such officer's knowledge,

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based on such review, the Master Servicer or such Servicer has fulfilled all its obligations under the applicable Pooling and Servicing Agreement or Underlying Servicing Agreement in all material respects throughout such year, or, if there has been a failure to fulfill any such obligation in any material respect, specifying each such failure known to such officer and the nature and status of the failure.

In addition, each Servicer and any other party that participates in the servicing and administration of the Mortgage Loans and other assets comprising a Trust will deliver annually a report that assesses compliance by that party, on a "servicing platform" level, with the servicing criteria set forth in Item 1122(d) of Regulation AB (17 C.F.R. 229.1122) (an "Assessment of Compliance") and each such Assessment of Compliance will contain the following:

o a statement of the party's responsibility for assessing compliance with the servicing criteria applicable to it;

o a statement that the party used the criteria in Item 1122(d) of Regulation AB to assess compliance with the applicable servicing criteria;

o the party's Assessment of Compliance for and as of the end of the prior calendar year, setting forth any material instance of noncompliance identified by the party; and

o a statement that a registered public accounting firm has issued an attestation report on the party's Assessment of Compliance for and as of the end of the prior calendar year.

Each party that is required to deliver an Assessment of Compliance will also be required to simultaneously deliver a report (an "Attestation Report") of a registered public accounting firm, prepared in accordance with the standards for attestation engagements issued or adopted by the Public Company Accounting Oversight Board, that expresses an opinion, or states that an opinion cannot be expressed, concerning the party's Assessment of Compliance.

Changes in Servicing

Changes in Timing of Remittances of Unscheduled Principal Receipts in Full and Elimination of Month End Interest

The Pooling and Servicing Agreement for each Series will provide that the Master Servicer may (but is not required), from time to time and without the consent of any Certificateholder or the Trustee, enter into an amendment (a) to an Underlying Servicing Agreement of any Servicer other than Wells Fargo Bank for the purpose of (i) eliminating or reducing Month End Interest and (ii) providing for the remittance of Unscheduled Principal Receipts in full by the applicable Servicer to the Master Servicer not later than the 24th day of each month (or if such day is not a business day, the previous business day), (b) to the Underlying Servicing Agreement of Wells Fargo Bank for the purpose of changing the applicable Remittance Date to the 18th day of each month (or if such day is not a business day, on the previous business day) or (c) to any Underlying Servicing Agreement for the purpose of effecting or facilitating compliance by the Servicer with Regulation AB (17 C.F.R. 229) or to conform the Underlying Servicing Agreement to industry practices relating to Regulation AB (17 C.F.R. 229). The Pooling and Servicing Agreement permits the Master Servicer to direct Wells Fargo Bank, as Servicer, to enter into any amendment pursuant to clause (b) or (c) of the immediately preceding sentence. No assurance can be given as to the timing of any such changes or that any such changes will occur.

Changes in Unscheduled Principal Receipt Period

The Pooling and Servicing Agreement for each Series will provide that the Master Servicer may (but is not required to), from time to time and without the consent of any Certificateholder or the Trustee, (i) direct Wells Fargo Bank, as Servicer under the related Underlying Servicing Agreement to change the Unscheduled Principal Receipt Period for the Type 2 Loans (to achieve consistency with the Type 1 Loans) to a Mid-Month Receipt Period and (ii) make any conforming changes incident thereto.

Changing the applicable Unscheduled Principal Receipt Period from a Prior Month Receipt Period to a Mid-Month Receipt Period may decrease the amount of interest shortfalls with respect to the applicable type of

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Unscheduled Principal Receipt. However, no assurance can be given as to the timing of any change to any Unscheduled Principal Receipt Period or that any such changes will occur.

Servicer Defaults

The Master Servicer, or if Wells Fargo Bank is the Servicer or the Underlying Servicing Agreement so provides, the Trustee will have the right pursuant to the Underlying Servicing Agreements to terminate a Servicer in certain events, including the breach by such Servicer of any of its material obligations under its Underlying Servicing Agreement. In the event of such termination, (i) the Trustee may enter into a substitute Underlying Servicing Agreement with the Master Servicer or another servicing institution acceptable to the Trustee and each Rating Agency; and (ii) in the case of a Servicer other than Wells Fargo Bank, the Master Servicer shall assume certain of the Servicer's servicing obligations under such Underlying Servicing Agreement, including the obligation to make Periodic Advances (limited as provided herein under the heading "Servicing of the Mortgage Loans--Periodic Advances and Limitations Thereon"), until such time as a successor servicer is appointed. The Master Servicer will be entitled to reimbursement for the costs and expenses associated with the transfer, including indemnity payments owed to the Trustee in connection with directing the Trustee to terminate an Underlying Servicing Agreement. To the extent the terminated Servicer does not reimburse the Master Servicer, the Master Servicer is entitled to reimbursement out of the Certificate Account which may result in a loss to the Certificates of the related Series. See "Servicing of the Mortgage Loans--Fixed Retained Yield, Servicing Compensation and Payment of Expenses".

THE POOLING AND SERVICING AGREEMENT

Assignment of Mortgage Loans to the Trustee

The Depositor will have acquired the Mortgage Loans included in each Trust Estate containing Mortgage Loans from Wells Fargo Bank pursuant to an agreement dated the applicable Closing Date (the "Mortgage Loan Purchase Agreement") between Wells Fargo Bank and the Depositor. In connection with the conveyance of the Mortgage Loans to the Depositor, Wells Fargo Bank will (i) agree to deliver to the Trustee or the custodian all of the documents which the Depositor is required to deliver to the Trustee; (ii) make certain representations and warranties to the Depositor which will be the basis of certain of the Depositor's representations and warranties to the Trustee or assign the representations and warranties made by a Correspondent to Wells Fargo Bank; and
(iii) agree to repurchase or substitute (or assign rights to a comparable agreement of a Correspondent) for any Mortgage Loan for which any document is not delivered or is found to be defective in any material respect, or which Mortgage Loan is discovered at any time not to be in conformance with any representation and warranty Wells Fargo Bank has made to the Depositor, if Wells Fargo Bank cannot deliver such document or cure such defect or breach within 60 days after notice thereof. In the event of a breach of a representation or warranty, generally there is no obligation to repurchase the affected Mortgage Loan or substitute a new Mortgage Loan therefor unless the breach materially and adversely affects the interests of the Certificateholders in the related Mortgage Loan. Such agreement will inure to the benefit of the Trustee and is intended to help ensure the Depositor's performance of its limited obligation to repurchase or substitute for Mortgage Loans. In addition, in the case of a breach of the representation that a Mortgage Loan at the time of its origination complied with any applicable federal, state or local predatory or abusive lending laws, Wells Fargo Bank will be required to pay to the Depositor any amount that the Depositor is required to pay pursuant to the Pooling and Servicing Agreement due to any costs or damages incurred by the Trust as a result of the violation of such laws. See "The Pooling and Servicing Agreement--Representations and Warranties."

At the time of issuance of each Series of Certificates issued by a Trust containing Mortgage Loans, the Mortgage Loans in the related Trust Estate will, pursuant to the applicable Pooling and Servicing Agreement, be assigned to the Trustee, together with all principal and interest received on or with respect to such Mortgage Loans after the applicable Cut-Off Date other than principal and interest due and payable on or before such Cut-Off Date and interest attributable to the Fixed Retained Yield on such Mortgage Loans, if any. See "Servicing of the Mortgage Loans--Fixed Retained Yield, Servicing Compensation and Payment of Expenses." The Trustee or its agent will, concurrently with such assignment, authenticate and deliver the Certificates evidencing such Series to the Depositor in exchange for the Mortgage Loans. Each Mortgage Loan will be identified in a schedule delivered to the applicable Trustee or custodian. Each such schedule will include, among other things, the unpaid principal balance

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as of the close of business on the applicable Cut-Off Date, the maturity date and the Mortgage Interest Rate for each Mortgage Loan in the related Trust Estate.

In addition, with respect to any Mortgage Loan in a Trust Estate, the mortgage or other promissory note or a lost note affidavit executed by the applicable Servicer, any assumption, consolidation, modification or conversion to fixed interest rate agreement and, a mortgage assignment in recordable form (or other documents as are required under applicable law to create perfected security interest in the Mortgaged Property in favor of the Trustee) will be delivered to the Trustee or, if indicated in the applicable prospectus supplement, to a custodian, which may be Wells Fargo Bank. Unless otherwise required by the Rating Agencies, assignments of the Mortgage Loans to the Trustee (or its nominee) will not be recorded in any jurisdiction, but will be delivered to the Trustee (or a custodian indicated in the applicable prospectus supplement) in recordable form, so that they can be recorded in the event recordation is necessary in connection with the servicing of a Mortgage Loan.

Notwithstanding the preceding paragraph, with respect to any Mortgage which has been recorded in the name of Mortgage Electronic Registration Systems, Inc. ("MERS") or its designee, no mortgage assignment in favor of the Trustee will be required to be prepared or delivered. Instead, the applicable Servicer will be required to take all actions as are necessary to cause the applicable Trust Estate to be shown as the owner of the related Mortgage Loan on the records of MERS for purposes of the system of recording transfers of beneficial ownership of mortgages maintained by MERS.

The Trustee or custodian will hold all Mortgage Loan documents delivered to it in trust for the benefit of Certificateholders of the related Series and will review such documents within 45 days of the date of the applicable Pooling and Servicing Agreement. If any document is not delivered or is found to be defective in any material respect, or if the Depositor is in breach of any of its representations and warranties, and such breach (other than certain breaches with respect to the principal balance of a Mortgage Loan) materially and adversely affects the interests of the Certificateholders in a Mortgage Loan, and the Depositor cannot deliver such document or cure such defect or breach within 60 days after receipt of final certification from the Trustee or custodian listing such defects or written notice of any such breach, the Depositor will, within 60 days of such certification or notice, either repurchase the related Mortgage Loan from the Trustee at a price equal to the then unpaid principal balance thereof, plus accrued and unpaid interest at the applicable Mortgage Interest Rate (minus any Fixed Retained Yield) through the last day of the month in which such repurchase takes place, or (in the case of a Series for which one or more REMIC elections have been or will be made, unless the maximum period as may be provided by the Code or applicable regulations of the Department of the Treasury ("Treasury Regulations") shall have elapsed since the execution of the applicable Pooling and Servicing Agreement) substitute for such Mortgage Loan a new mortgage loan having characteristics such that the representations and warranties of the Depositor made pursuant to the applicable Pooling and Servicing Agreement (except for representations and warranties as to the correctness of the applicable schedule of mortgage loans) would not have been incorrect had such substitute Mortgage Loan originally been a Mortgage Loan. In the case of a repurchased Mortgage Loan, the purchase price will be deposited by the Depositor in the Certificate Account. In the case of a substitute Mortgage Loan, the mortgage file relating thereto will be delivered to the Trustee or the custodian and the Depositor will deposit in the Certificate Account, an amount equal to the excess of (i) the unpaid principal balance of the Mortgage Loan which is substituted for, over (ii) the unpaid principal balance of the substitute Mortgage Loan, together with interest on such excess at the Mortgage Interest Rate (minus any Fixed Retained Yield) to the next scheduled Due Date of the Mortgage Loan which is being substituted for. In no event will any substitute Mortgage Loan have an unpaid principal balance greater than the Scheduled Principal Balance of the Mortgage Loan for which it is substituted (after giving effect to the scheduled principal payment due in the month of substitution on the Mortgage Loan substituted for), or a term greater than, a Net Mortgage Interest Rate different than or a Loan-to-Value Ratio greater than, the Mortgage Loan for which it is substituted. If substitution is to be made for an adjustable rate Mortgage Loan, the substitute Mortgage Loan will have an unpaid principal balance no greater than the Scheduled Principal Balance of the Mortgage Loan for which it is substituted (after giving effect to the scheduled principal payment due in the month of substitution on the Mortgage Loan substituted for), a Loan-to-Value Ratio less than or equal to, and a Net Mortgage Interest Rate equal to, that of the Mortgage Loan for which it is substituted, and will bear interest based on the same index, margin and frequency of adjustment as the substituted Mortgage Loan. The repurchase obligation and the mortgage substitution referred to above will constitute the sole remedies available to the Certificateholders or the Trustee with respect to missing or defective documents or breach of the Depositor's representations and warranties. However, the Depositor may be required to pay additional amounts to the applicable Trust upon the breach of the representation

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that a Mortgage Loan at the time of its origination complied with any applicable federal, state or local predatory or abusive lending laws, as described under "The Pooling and Servicing Agreement--Representations and Warranties."

The "Scheduled Principal Balance" of a Mortgage Loan as of any Distribution Date is the unpaid principal balance of such Mortgage Loan as specified in the amortization schedule at the time relating thereto (before any adjustment to such schedule by reason of bankruptcy (other than Deficient Valuations), moratorium or similar waiver or grace period or any Capitalized Advance Amounts) as of the Due Date occurring in the month preceding the month in which such Distribution Date occurs, after giving effect to any principal prepayments or other unscheduled recoveries of principal previously received, to any partial principal prepayments and Deficient Valuations occurring prior to such Due Date, to the payment of principal due on such Due Date irrespective of any delinquency in payment by the mortgagor, to the principal portion of any Realized Losses as a result of Servicer Modifications incurred prior to such Due Date and to any Unscheduled Principal Receipts (net of unreimbursed Periodic Advances, if applicable) received or applied during the applicable Unscheduled Principal Receipt Period for the Distribution Date in the month preceding the month in which such Distribution Date occurs or any Deficient Valuations occurring during the period corresponding to the applicable Unscheduled Principal Receipt Period for principal prepayments in full for such preceding Distribution Date.

A "Servicer Modification" with respect to a Mortgage Loan is a modification to the terms of such Mortgage Loan as to which the mortgagor is in default or as to which, in the judgment of the Servicer, default is reasonably foreseeable.

The "Capitalized Advance Amount" as of any Distribution Date is the amount of Advances that have been added to the unpaid principal balance of a Mortgage Loan in connection with a Servicer Modification.

Representations and Warranties

In connection with the transfer of the Mortgage Loans related to any Series by the Depositor to the Trust Estate, the Depositor will generally make certain representations and warranties regarding the Mortgage Loans. In certain cases in which Wells Fargo Bank acquired some or all of the Mortgage Loans related to a Series from a Correspondent, if so indicated in the applicable prospectus supplement, the Depositor may, rather than itself making representations and warranties, cause the representations and warranties made by the Correspondent in connection with its sale of Mortgage Loans to Wells Fargo Bank or the Wells Fargo Affiliates to be assigned to the Trust Estate. In such cases, the Correspondent's representations and warranties may have been made as of a date prior to the date of execution of the Pooling and Servicing Agreement. Such representations and warranties (whether made by the Depositor or another party) will generally include the following with respect to the Mortgage Loans, or each Mortgage Loan, as the case may be:

(i) the schedule of Mortgage Loans delivered to the applicable Trustee or custodian is correct in all material respects at the date or dates respecting which such information is furnished as specified therein;

(ii)immediately prior to the transfer and assignment contemplated by the Pooling and Servicing Agreement, the Depositor is the sole owner and holder of the Mortgage Loan, free and clear of any and all liens, pledges, charges or security interests of any nature and has full right and authority to sell and assign the same;

(iii) no Mortgage Note or Mortgage is subject to any right of rescission, set-off, counterclaim or defense;

(iv)the Mortgage Loan is covered by a title insurance policy (or in the case of any Mortgage Loan secured by a Mortgaged Property located in a jurisdiction where such policies are generally not available, an opinion of counsel of the type customarily rendered in such jurisdiction in lieu of title insurance is instead received);

(v) the Mortgage is a valid, subsisting and enforceable first lien on the related Mortgaged Property and the Mortgaged Property is free and clear of all encumbrances and liens having a priority over the first lien of the Mortgage except for those liens set forth in the Pooling and Servicing Agreement;

(vi) the Mortgaged Property is undamaged by water, fire, earthquake or earth movement, windstorm, flood, tornado or similar casualty (excluding casualty from the presence of hazardous wastes or hazardous substances,

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as to which no representation is made), in a manner which would adversely affect the value of the Mortgaged Property as security for the Mortgage Loan or the use for which the premises was intended;

(vii) all payments required to be made up to the Due Date immediately preceding the Cut-Off Date for such Mortgage Loan under the terms of the related Mortgage Note have been made and no Mortgage Loan had more than one delinquency in the 12 months preceding the Cut-Off Date;

(viii) each Mortgage Loan at the time it was originated complied in all material respects with applicable federal, state and local laws including, without limitation, usury, truth-in-lending, real estate settlement procedures, consumer credit protection, equal credit opportunity, predatory and abusive lending laws and disclosure laws;

(ix) no Mortgage Loan is a "high cost" loan as defined under any federal, state or local law applicable to such Mortgage Loan at the time of its origination; and

(x) no error, omission, misrepresentation, negligence, fraud or similar occurrence with respect to a Mortgage Loan has taken place on the part of Wells Fargo Bank, as an originator, or the mortgagor (except with respect to the accuracy of information regarding the mortgagor's income, source of income, or assets that is stated on the loan application by the mortgagor but not verified in the origination process pursuant to the underwriting guidelines applicable at the time of origination), or to the best of the Depositor's knowledge, any appraiser, any builder, or any developer, or any other party involved in the origination of the Mortgage Loan or in the application of any insurance in relation to such Mortgage Loan.

No representations or warranties are made by the Depositor or any other party as to the environmental condition of any Mortgaged Property including the absence, presence or effect of hazardous wastes or hazardous substances on such Mortgaged Property or any effect from the presence or effect of hazardous wastes or hazardous substances on, near or emanating from such Mortgaged Property. See "Certain Legal Aspects of the Mortgage Loans--Environmental Considerations" below.

See "--Assignment of Mortgage Loans to the Trustee" above for a description of the limited remedies available in connection with breaches of the foregoing representations and warranties. In addition to those remedies, in the case of a breach of the representation that a Mortgage Loan at the time of its origination complied with any applicable federal, state or local predatory or abusive lending laws, the Depositor (or other party making such representation) will be required to pay any costs or damages incurred by the applicable Trust as a result of the violation of such laws. Wells Fargo Bank will be required to pay to the Depositor any amount that the Depositor is required to pay pursuant to the immediately preceding sentence.

Optional Purchases

Subject to the requirements of the applicable Pooling and Servicing Agreement, the Depositor or the Master Servicer may, at such party's option, repurchase (i) any Mortgage Loan which is in default during one or more thirty-day periods specified in the Pooling and Servicing Agreement and (ii) any defaulted Mortgage Loan or Mortgage Loan as to which default is reasonably foreseeable as to which the originator of such Mortgage Loan breached a representation or warranty to Wells Fargo Bank, as Sponsor, regarding the characteristics of such Mortgage Loan, at a price equal to the unpaid principal balance thereof plus accrued interest thereon.

Reports to Certificateholders

The Master Servicer will, based on information provided by the Servicer, prepare and make available via the internet to Certificateholders of record of each Series backed by Mortgage Loans a Monthly Report setting forth the following information, if applicable:

(i) the applicable Determination Date, applicable record date and interest accrual period (if any) for calculating the distribution and the actual Distribution Date for the distribution;

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(ii) the amount of such distribution allocable to principal of the related Mortgage Loans, separately identifying the aggregate amount of any principal prepayments and Liquidation Proceeds and the amount of such distribution allocable to interest on the related Mortgage Loans;

(iii) if the distribution to Certificateholders is less than the full amount that would be distributable if there were sufficient funds available, the amount of the shortfall, the allocation of the shortfall between principal and interest and the aggregate amount of unpaid shortfalls with respect to the applicable Distribution Date and all prior Distribution Dates;

(iv) the amount of principal and interest paid on each Class of Certificates and the principal balance of each Class of Certificates prior to and after giving effect to the distributions of principal on the Distribution Date;

(v) the amount of master servicing compensation and servicing compensation with respect to the related Trust Estate and such other customary information as is required to enable Certificateholders to prepare their tax returns;

(vi) the amount of the aggregate Servicing Fees paid to each Servicer and Master Servicing Fees paid to the Master Servicer and the amount by which the master servicing compensation for the related Distribution Date has been reduced by interest shortfalls due to prepayments;

(vii) the amount of any Periodic Advances by any Servicer, the Master Servicer or the Trustee included in the amounts actually distributed to the Certificateholders;

(viii) to each holder of a Certificate entitled to the benefits of payments under any form of credit enhancement or from any reserve fund:

(a) the amounts so distributed under any such form of credit enhancement or from any such reserve fund on the applicable Distribution Date; and

(b) the amount of coverage remaining under any such form of credit enhancement and the balance in any such reserve fund, after giving effect to any payments thereunder and other amounts charged thereto on the Distribution Date;

(ix) any payments made or accrued relating to credit enhancement provided by a party, identifying the general purpose of the payments and the party receiving the payments;

(x) the Pass-Through Rate (if any) for each Class of Certificates;

(xi) the total number and principal balance of any REO Properties (and market value, if available) as of the close of business on the Determination Date preceding the Distribution Date;

(xii) the aggregate amount of Realized Losses incurred during the preceding calendar month;

(xiii) any expenses or indemnification amounts paid by the related Trust Estate, the specific purpose of each payment and the parties to whom these payments are made;

(xiv) the number and total principal balance of the Mortgage Loans as of the previous Distribution Date and the related Distribution Date, the weighted average mortgage interest rate and weighted average remaining term to maturity of the Mortgage Loans and cumulative prepayment amounts for the related Distribution Date;

(xv) the beginning and ending balances of the Certificate Account and any reserve fund for a Series;

(xvi) any material modifications, extensions or waivers to Mortgage Loan terms, fees, penalties or payments since the previous Distribution Date or cumulatively since the Closing Date;

(xvii) any material breaches of representations and warranties relating to the Mortgage Loans or material breaches of transaction covenants;

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(xviii) the number and aggregate principal amounts of Mortgage Loans (A) delinquent (exclusive of Mortgage Loans in foreclosure or bankruptcy) (for purposes of determining delinquency, a Mortgage Loan is considered delinquent if a payment was not received by the end of the month in which such payment was due), (B) in foreclosure, as of the close of business on the last day of the calendar month preceding the Distribution Date and (C) in bankruptcy as of the close of business on the last day of the calendar month preceding the Distribution Date;

(xix) the number and aggregate unpaid principal balances of the Mortgage Loans by range of current Mortgage Interest Rates;

(xx) pool factors for the related Distribution Date;

(xxi) the amount of excess cash flow, if any, for the related Distribution Date;

(xxii) with respect to any Mortgage Loan as to which there has been a Servicer Modification in the calendar month preceding the Distribution Date, the Scheduled Principal Balance as of the Distribution Date, the scheduled payment prior to modification and the scheduled payment after modification; and

(xxiii) whether any exchanges of Exchangeable REMIC Certificates and Exchangeable Certificates have taken place since the preceding Distribution Date and, if applicable, the class designations, principal balances or notional amounts, Pass-Through Rates, and any interest and/or principal paid, including any shortfalls allocated, with respect to any Classes of Certificates that were received by Certificateholders as a result of such exchange.

In addition, the Master Servicer will include in the statement any information specific to the Classes of Certificates offered by the applicable prospectus supplement and, within a reasonable period of time after the end of each calendar year, the Paying Agent will, upon request, furnish (or cause to be furnished) a report to each Certificateholder of record at any time during such calendar year such information as required by the Code and applicable regulations thereunder to enable Certificateholders to prepare their tax returns. In the event that an election has been made to treat the Trust Estate (or one or more segregated pools of assets therein) as a REMIC, the Trustee will be required to sign the federal and applicable state and local income tax returns of the REMIC (which will be prepared by the Master Servicer). See "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates--Administrative Matters."

List of Certificateholders

The Pooling and Servicing Agreement for each Series will require the Master Servicer or other entity acting as certificate registrar to provide access to the most current list of names and addresses of Certificateholders of such Series to any group of five or more Certificateholders who advise the Master Servicer or other entity acting as certificate registrar in writing that they desire to communicate with other Certificateholders with respect to their rights under the Pooling and Servicing Agreement or under the Certificates.

Events of Default

Events of Default under the Pooling and Servicing Agreement for each Series include (i) any failure by the Master Servicer to make a required deposit which continues unremedied for three business days after either (a) receipt by the Master Servicer of written notice of such failure by the Trustee for such Series, or to the Master Servicer and the Trustee by the holders of Certificates of such Series having voting rights allocated to such Certificates ("Voting Interests") aggregating not less than 25% of the Voting Interests represented by all Certificates for such Series or (b) solely in the case of the Master Servicer failing to remit any Periodic Advance, the date on which the Master Servicer certifies the amount of Periodic Advances for such Distribution Date to the Trustee; (ii) any failure by the Master Servicer duly to observe or perform in any material respect any other of its covenants or agreements in the Pooling and Servicing Agreement, or any material breach by the Master Servicer of its representations and warranties made in the Pooling and Servicing Agreement resulting in a loss to the Depositor or the related Trust Estate, which continues unremedied for 60 days after the giving of written notice of such failure to the Master Servicer by the Trustee or the Depositor, or to the Master Servicer and the Trustee by the holders of Certificates aggregating not less than 25% of the Voting Interests represented by all of the Certificates for such Series, or which continues unremedied for a lesser number of days set forth in the applicable Pooling and Servicing

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Agreement in the case of a failure to perform any covenants or agreements relating to the requirements of Regulation AB (17 C.F.R. 229), (iii) certain events of insolvency, readjustment of debt, marshaling of assets and liabilities or similar proceedings and certain actions by the Master Servicer indicating its insolvency, reorganization or inability to pay its obligations and (iv) the Master Servicer and any subservicer appointed by it becoming ineligible to service for both Fannie Mae and Freddie Mac (unless remedied within 90 days).

Upon the occurrence of an Event of Default under the Pooling and Servicing Agreement for a Series, the Trustee will be required pursuant to the applicable Pooling and Servicing Agreement to (a) give prompt notice to each Rating Agency of the Event of Default and (b) within 45 days after the occurrence of any Event of Default known to the Trustee, give written notice thereof to Certificateholders of a Series, unless such Event of Default shall have been cured or waived within said 45 day period.

Rights Upon Event of Default

So long as an Event of Default remains unremedied under the Pooling and Servicing Agreement for a Series, the Trustee for such Series or holders of Certificates of such Series evidencing not less than 66 2/3% of the Voting Interests in the Trust Estate for such Series may terminate all of the rights and obligations of the Master Servicer under the Pooling and Servicing Agreement and in and to the Mortgage Loans (other than the Master Servicer's right to recovery of the aggregate Master Servicing Fees due prior to the date of termination, and other expenses and amounts advanced pursuant to the terms of the Pooling and Servicing Agreement, which rights the Master Servicer will retain under all circumstances), whereupon the Trustee will succeed to all the responsibilities, duties and liabilities of the Master Servicer under the Pooling and Servicing Agreement and will be entitled to monthly compensation not to exceed the aggregate Master Servicing Fees together with the other compensation to which the Master Servicer is entitled under the Pooling and Servicing Agreement. In the event that the Trustee is unwilling or unable so to act, it may select, pursuant to the public bid procedure described in the applicable Pooling and Servicing Agreement, or petition a court of competent jurisdiction to appoint, a housing and home finance institution, bank or mortgage servicing institution with a net worth of at least $10,000,000 to act as successor to the Master Servicer under the provisions of the Pooling and Servicing Agreement; provided however, that until such a successor Master Servicer is appointed and has assumed the responsibilities, duties and liabilities of the Master Servicer under the Pooling and Servicing Agreement, the Trustee shall continue as the successor to the Master Servicer as described above. In the event such public bid procedure is utilized, the successor would be entitled to compensation in an amount equal to the aggregate Master Servicing Fees, together with the other compensation to which the Master Servicer is entitled under the Pooling and Servicing Agreement, and the Master Servicer would be entitled to receive the net profits, if any, realized from the sale of its rights and obligations under the Pooling and Servicing Agreement. The Trustee or the successor Master Servicer or Servicer will be entitled to be reimbursed from the predecessor Master Servicer (or the Trust if the predecessor Master Servicer is unable to fulfill its obligations under the Pooling and Servicing Agreement) for all costs associated with the transfer of servicing.

During the continuance of any Event of Default under the Pooling and Servicing Agreement for a Series, the Trustee for such Series will have the right to take action to enforce its rights and remedies and to protect and enforce the rights and remedies of the Certificateholders of such Series, and holders of Certificates evidencing not less than 25% of the Voting Interests for such Series may direct the time, method and place of conducting any proceeding for any remedy available to the Trustee or exercising any trust or power conferred upon the Trustee. However, the Trustee will not be under any obligation to pursue any such remedy or to exercise any of such trusts or powers unless such Certificateholders have offered the Trustee reasonable security or indemnity against the cost, expenses and liabilities which may be incurred by the Trustee thereby. Also, the Trustee may decline to follow any such direction if the Trustee determines that the action or proceeding so directed may not lawfully be taken or would involve it in personal liability or be unjustly prejudicial to the non-assenting Certificateholders.

No Certificateholder of a Series, solely by virtue of such holder's status as a Certificateholder, will have any right under the Pooling and Servicing Agreement for such Series to institute any proceeding with respect to the Pooling and Servicing Agreement, unless such holder previously has given to the Trustee for such Series written notice of default and unless the holders of Certificates evidencing not less than 25% of the Voting Interests for such Series have made written request upon the Trustee to institute such proceeding in its own name as Trustee thereunder and have offered to the Trustee reasonable indemnity and the Trustee for 60 days has neglected or refused to institute any such proceeding.

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Amendment

Each Pooling and Servicing Agreement may be amended by the Depositor, the Master Servicer and the Trustee without the consent of the Certificateholders,
(i) to cure any ambiguity or mistake, (ii) to correct or supplement any provision therein that may be inconsistent with any other provision therein or in this prospectus or the applicable prospectus supplement, (iii) to modify, eliminate or add to any of its provisions to such extent as shall be necessary to maintain the qualification of the related Trust Estate (or one or more segregated pools of assets therein) as a REMIC at all times that any Certificates are outstanding or to avoid or minimize the risk of the imposition of any tax on such Trust Estate pursuant to the Code that would be a claim against such Trust Estate, provided that the Trustee has received an opinion of counsel to the effect that such action is necessary or desirable to maintain such qualification or to avoid or minimize the risk of the imposition of any such tax and such action will not, as evidenced by such opinion of counsel, adversely affect in any material respect the interests of any Certificateholder,
(iv) to conform the obligations of the parties under the Pooling and Servicing Agreement, if necessary, to comply with the requirements of Regulation AB (17 C.F.R. 229), (v) to change the timing and/or nature of deposits into the Certificate Account, provided that such change will not, as evidenced by an opinion of counsel, adversely affect in any material respect the interests of any Certificateholder, (vi) to add to, modify or eliminate any provisions therein restricting transfers of the Certificates of a Series provided that the Depositor has determined in its sole discretion that any such modifications to the Pooling and Servicing Agreement will neither adversely affect the ratings on the Certificates nor give rise to a risk that the applicable REMIC or any Certificateholders will be subject to a tax caused by a transfer to a non-permitted transferee, (vii) to make certain provisions with respect to the form and/or denominations of, the manner of payments on or the transfer restrictions applicable to, certain Classes of Certificates initially retained by the Depositor or an affiliate, or (viii) to make any other provisions with respect to matters or questions arising under such Pooling and Servicing Agreement that are not inconsistent with the provisions thereof, provided that such action will not, as evidenced by an opinion of counsel, adversely affect in any material respect the interests of the Certificateholders of the related Series. Notwithstanding the foregoing, such action described in clause (v) or
(viii) will not be considered to adversely affect in any material respect the interest of Certificateholders and no opinion of counsel to that effect will be required if each Rating Agency rating the Certificates states in writing that such action would not result in the downgrading or withdrawal of the ratings then assigned to the Certificates. The Pooling and Servicing Agreement may also be amended by the Depositor, the Master Servicer and the Trustee with the consent of the holders of Certificates evidencing interests aggregating not less than 66 2/3% of the Voting Interests evidenced by the Certificates of each Class affected thereby, for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of such Pooling and Servicing Agreement or of modifying in any manner the rights of the Certificateholders; provided, however, that no such amendment may (i) reduce in any manner the amount of, or delay the timing of, any payments received on or with respect to Mortgage Loans that are required to be distributed on any Certificates, without the consent of the holder of such Certificate, (ii) adversely affect in any material respect the interests of the holders of a Class of Certificates of a Series in a manner other than that set forth in (i) above without the consent of the holders of Certificates aggregating not less than 66 2/3% of the Voting Interests evidenced by such Class, or (iii) reduce the aforesaid percentage of Certificates of any Class, the holders of which are required to consent to such amendment, without the consent of the holders of all Certificates of such Class affected then outstanding. Notwithstanding the foregoing, the Trustee will not consent to any such amendment if such amendment would subject the related Trust Estate (or any segregated pool of assets therein) to tax or cause the Trust Estate (or any segregated pool of assets therein) to fail to qualify as a REMIC.

Termination; Optional Purchase of Mortgage Loans

The obligations created by the Pooling and Servicing Agreement for a Series of Certificates will terminate on the Distribution Date following the final payment or other liquidation of the last Mortgage Loan subject thereto and the disposition of all property acquired upon foreclosure of any such Mortgage Loan. In no event, however, will the trust created by the Pooling and Servicing Agreement continue beyond the expiration of 21 years from the death of the last survivor of certain persons named in such Pooling and Servicing Agreement. For each Series of Certificates issued by a Trust containing Mortgage Loans, the Paying Agent will give written notice of termination of the Pooling and Servicing Agreement to each Certificateholder, and the final distribution will be made only upon surrender and cancellation of the Certificates at an office or agency appointed by the Depositor and specified in the notice of termination.

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The Pooling and Servicing Agreement for each Series of Certificates will permit, but not require, the Depositor, Wells Fargo Bank or such other party as is specified in the applicable prospectus supplement, to purchase from the Trust Estate for such Series all remaining Mortgage Loans and any REO Property (or one or more groups of Mortgage Loans and any related REO Property, if specified in the applicable prospectus supplement), and thereby effect an early retirement of the applicable Series of Certificates (or in the case of the optional purchase of one or more, but less than all, groups of Mortgage Loans, the Certificates relating to such group or groups), at a price equal to the sum of (a) the unpaid principal balance of each Mortgage Loan in the applicable group or groups plus
(b) the fair market value of other property (including any Mortgaged Property title to which has been acquired by the Trust Estate ("REO Property")) in the Trust Estate (or the related group or groups, if specified in the applicable prospectus supplement) plus accrued and unpaid interest. However, for so long as the purchasing party is subject to regulation by the OCC, the FDIC, the Federal Reserve or the OTS, the purchasing party may exercise its purchase option only if the aggregate fair market value of the Mortgage Loans and REO Properties is greater than or equal to the purchase price described in the preceding sentence. This right to purchase all remaining Mortgage Loans of a Series backed by Mortgage Loans (or one or more groups of Mortgage Loans of such Series, if specified in the applicable prospectus supplement) may be exercised on any Distribution Date when the aggregate Scheduled Principal Balance of the applicable Mortgage Loans is less than 10% of the aggregate unpaid principal balance of the applicable Mortgage Loans as of the Cut-Off Date for such Series or a lower percentage specified in the applicable prospectus supplement.

In the event that such party has caused the related Trust Estate (or any segregated pool of assets therein) to be treated as a REMIC, any such purchase will be effected only pursuant to a "qualified liquidation" as defined in Code
Section 860F(a)(4)(A) and, if the Trust Estate is liquidated other than in the manner specified in the Pooling and Servicing Agreement, the receipt by the Trustee and the Master Servicer of an opinion of counsel or other evidence that such other liquidation method (i) will constitute a "qualified liquidation" of the Trust Estate within the meaning of Code Section 860F(a)(4)(A) and (ii) will not cause the Trust Estate (or any segregated pool of assets) to fail to qualify as a REMIC. The exercise of such right will effect early retirement of the Certificates of that Series (or in the case of the optional purchase of one or more, but less than all, groups of Mortgage Loans, the Certificates relating to such group or groups), but the right so to purchase may be exercised only after the aggregate principal balance of the applicable Mortgage Loans at the time of purchase is less than a specified percentage of the aggregate principal balance at the Cut-Off Date for the Series, or after the date set forth in the applicable prospectus supplement.

The Trustee

The trustee under each Pooling and Servicing Agreement (each, a "Trustee") will be named in the applicable prospectus supplement. The commercial bank or trust company serving as Trustee may have normal banking relationships with the Depositor or any of its affiliates. With respect to certain Series of Certificates, a securities administrator may perform certain duties and functions normally performed by the Trustee. Any securities administrator will be a party to the Pooling and Servicing Agreement and will be named in the applicable prospectus supplement. Any securities administrator will have obligations and rights similar to the Trustee as described herein.

The Master Servicer will pay from its own funds (without right of reimbursement from the related Trust Estate) the fees of the Trustee incurred in connection with its responsibilities under the Pooling and Servicing Agreement.

The Pooling and Servicing Agreement will provide that the Trustee will be entitled to reimbursement from the Trust Estate for all reasonable expenses, disbursements and advances incurred or made by it in accordance with the provisions of the Pooling and Servicing Agreement to the extent permitted by Treasury regulations Section 1.860G-1(b)(3), which allows reimbursement for "unanticipated expenses," except (i) for any such expense, disbursement or advance arising from the Trustee's gross negligence, bad faith or willful misconduct and (ii) for any routine ongoing expenses incurred by the Trustee in the ordinary course of its duties. Any loss to the Trust Estate as a result of such reimbursement will be allocated first to the Subordinated Certificates of a Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable prospectus supplement.

The Trustee and any director, officer, employee or agent of the Trustee will be entitled to indemnification by the Trust Estate and held harmless against any loss, liability or expense (including reasonable attorney's fees) (a) incurred in connection with any claim or legal action relating to (i) the Pooling and Servicing Agreement, (ii) the

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Certificates, or (iii) the performance of any of the Trustee's duties under the Pooling and Servicing Agreement, unless the loss, liability or expense was incurred by reason of willful misfeasance, bad faith or gross negligence in the performance of any of the Trustee's duties under the Pooling and Servicing Agreement and (b) resulting from any tax or information return which was prepared by, or should have been prepared by, the applicable Servicer or Master Servicer.

The Trustee may resign at any time, in which event the Master Servicer will be obligated to appoint a successor trustee. The Master Servicer may also remove the Trustee if the Trustee ceases to be eligible to act as Trustee under the Pooling and Servicing Agreement, if the Trustee becomes incapable of acting as Trustee, if the Trustee becomes insolvent or in order to change the situs of the related Trust Estate for state tax reasons. Upon becoming aware of such circumstances, the Master Servicer will become obligated to appoint a successor trustee. The Trustee may also be removed at any time by the holders of Certificates evidencing not less than 51% of the Voting Interests in the related Trust Estate, except that, any Certificate registered in the name of the Depositor, the Master Servicer or any affiliate thereof will not be taken into account in determining whether the requisite Voting Interest in the Trust Estate necessary to effect any such removal has been obtained. Any resignation and removal of the Trustee, and the appointment of a successor trustee, will not become effective until acceptance of such appointment by the successor trustee. The Trustee, and any successor trustee, will be required to (a) be a corporation or association having its principal office in a state and city acceptable to the Depositor, organized and doing business under the laws of such state or the United States of America, authorized under such laws to exercise corporate trust powers having a combined capital and surplus of at least $50,000,000, or will be a member of a bank holding system, the aggregate combined capital and surplus of which is at least $50,000,000, provided that the Trustee's and any such successor trustee's separate capital and surplus shall at all times be at least the amount specified in Section 310(a)(2) of the Trust Indenture Act of 1939,
(b) be subject to supervision or examination by federal or state authorities and
(c) have a credit rating or be otherwise acceptable to the Rating Agencies.

In the event the predecessor trustee has resigned or is removed for cause, any costs associated with the appointment of a successor trustee are required to be paid by the predecessor and, if not paid, will be reimbursed to the successor trustee from the assets of the related Trust. Notwithstanding the foregoing, if the predecessor has been removed without cause, any costs associated with the appointment of a successor trustee will be reimbursed to the party incurring such costs from the assets of the related Trust.

The Custodian

The Sponsor or another entity (which may be the Trustee) named in the applicable prospectus supplement will act as custodian for each series of Certificates. Generally, the custodian will be responsible for holding and safeguarding the Mortgage Notes and other contents of the mortgage file on behalf of the Certificateholders of a Series.

If no custodian is initially named in the Pooling and Servicing Agreement, the Trustee will be authorized to appoint a custodian to maintain possession of the documents relating to the Mortgage Loans and to conduct the review of such documents described above. Any custodian so appointed will keep and review such documents as the Trustee's agent under a custodial agreement.

Subject to certain limitations, the custodian will be indemnified and held harmless by the Depositor from and against all claims, liabilities, losses, actions, suits or proceedings at law or in equity, or any other expenses, fees or charges, which the custodian may incur or with which the custodian may be threatened by reasons of its acting as custodian, including attorney's fees, and the cost of defending any action, suit or proceedings or resisting any claim other than any claim, liability, loss, action, suit or proceeding or other expense, fees, or charge caused by reason of any negligent act, negligent failure to act, or willful misconduct on the part of the custodian, or which shall constitute a willful breach of its duties.

Special Servicing Agreements

The Pooling and Servicing Agreement for a Series may permit the Master Servicer at the direction of the Depositor to enter into a special servicing agreement with an unaffiliated holder of a Class of Class B Certificates or of a class of securities representing interests in one or more Classes of Class B Certificates and/or other subordinated mortgage pass-through certificates. Pursuant to such an agreement, such holder may instruct the Master Servicer to

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instruct the Servicers, to the extent provided in the applicable Underlying Servicing Agreement to commence or delay foreclosure proceedings with respect to delinquent Mortgage Loans. Such commencement or delay at such holder's direction will be taken by the Master Servicer only after such holder deposits a specified amount of cash with the Master Servicer. Such cash will be available for distribution to Certificateholders if Liquidation Proceeds are less than they otherwise may have been had the Servicers acted pursuant to their normal servicing procedures. Such agreement may also provide for the right of the holder to purchase certain delinquent Mortgage Loans from the applicable Trust Estate at a price not less than the unpaid principal balance of such Mortgage Loans plus accrued interest thereon.

THE TRUST AGREEMENT

Assignment of Mortgage Certificates to the Trustee

The Depositor will have acquired the Mortgage Certificates included in the applicable Trust Estate from the Sponsor named in the applicable prospectus supplement pursuant to an agreement dated the applicable Closing Date (the "Mortgage Certificate Purchase Agreement") between such Sponsor and the Depositor. In connection with the conveyance of the Mortgage Certificates to the Depositor, the applicable Sponsor will (i) agree to deliver (by physical delivery or electronic book-entries through DTC) to the Trustee or the custodian (or other party specified in the applicable prospectus supplement) the Mortgage Certificates which the Depositor is required to deliver to the Trustee; (ii) make certain representations and warranties to the Depositor which will be the basis of certain of the Depositor's representations and warranties to the Trustee; and (iii) agree to repurchase any Mortgage Certificate under certain circumstances described in the applicable prospectus supplement. Generally there is no obligation to repurchase the affected Mortgage Certificate unless the breach materially and adversely affects the interests of the Certificateholders of a Series in the related Mortgage Certificate. Such agreement will inure to the benefit of the Trustee and is intended to help ensure the Depositor's performance of its limited obligation to repurchase Mortgage Certificates. See "--Representations and Warranties" below.

At the time of issuance of each Series of Certificates issued by a Trust containing Mortgage Certificates, such Mortgage Certificates will, pursuant to the applicable Trust Agreement, be assigned to the Trustee or Securities Administrator, on behalf of the Trustee, together with all distributions received on or with respect to such Mortgage Certificates after the applicable Cut-Off Date. The Trustee or its agent will, concurrently with such assignment, authenticate and deliver the Certificates evidencing such Series to the Depositor in exchange for the Mortgage Certificates. Each Mortgage Certificate will be identified in a schedule delivered to the applicable Trustee and the Securities Administrator. Each such schedule will include, among other things, the unpaid principal balance, the final distribution date and the Mortgage Certificate Pass-Through Rate for each Mortgage Certificate in the related Trust Estate.

Representations and Warranties

In connection with the transfer of the Mortgage Certificates related to any Series by the Depositor to the Trust Estate, the Depositor will generally make certain representations and warranties regarding the Mortgage Certificates. In certain cases and if so indicated in the applicable prospectus supplement, the Depositor may, rather than itself making representations and warranties, cause the representations and warranties made by the Sponsor under the Mortgage Certificate Purchase Agreement to be assigned to the Trust Estate. Such representations and warranties (whether made by the Depositor or the Sponsor) will generally include the following with respect to the Mortgage Certificates, or each Mortgage Certificate, as the case may be:

(i) Immediately prior to the transfer and assignment contemplated by the Trust Agreement, the Depositor (or, if applicable, the Sponsor) was the sole owner and holder of the Mortgage Certificates. The Mortgage Certificates were not assigned or pledged by the Depositor and the Depositor had good and marketable title thereto, and the Depositor had full right to transfer and sell the Mortgage Certificates to the Trustee free and clear of any encumbrance, participation interest, lien, equity, pledge, claim or security interest and had full right and authority subject to no interest or participation in, or agreement with any other party to sell or otherwise transfer the Mortgage Certificates.

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(ii) As of the Closing Date, the Depositor has transferred all right, title and interest in the Mortgage Certificates to the Trustee on behalf of the Trust.

(iii) As of the Closing Date, the Depositor has not transferred the Mortgage Certificates to the Trustee on behalf of the Trust with any intent to hinder, delay or defraud any of its creditors.

See "--Assignment of Mortgage Certificates to the Trustee" above for a description of the limited remedies available in connection with breaches of the foregoing representations and warranties.

Payments on Mortgage Certificates

The Securities Administrator will, as to each Series of Certificates, establish and maintain a separate trust account in the name of the Securities Administrator on behalf of the Trustee (the "Certificate Account"). Such account may be established at Wells Fargo Bank or an affiliate thereof. Each such account must be maintained with a Depository either (i) whose long-term debt obligations (or, in the case of a depository institution which is part of a holding company structure, the long-term debt obligations of such parent holding company) are, at the time of any deposit therein rated in at least one of the two highest rating categories by each nationally recognized statistical rating organization that rated the related Series of Certificates, (ii) that is a federal or state charted depository institution or trust company acting in its fiduciary capacity with respect to such accounts which shall be trust accounts maintained with its trust department, or (iii) that is otherwise acceptable to the Rating Agency or Rating Agencies rating the Certificates of such Series and, if a REMIC election has been made, that would not cause the related Trust Estate (or one or more segregated pools of assets therein) to fail to qualify as a REMIC. To the extent that the portion of funds deposited in the Certificate Account at any time exceeds the limit of insurance coverage established by the FDIC, such excess will be subject to loss in the event of the failure of the Depository. Such insurance coverage will be based on the number of holders of Certificates. Holders of the Subordinated Certificates of a Series will bear any such loss up to the amount of principal payments on the related Mortgage Certificates to which such holders are entitled.

The Securities Administrator will be required to deposit in the Certificate Account for each applicable Series of Certificates on or before the Distribution Date of each month, the following amounts:

(a) all distributions received on the Mortgage Certificates since the preceding Distribution Date;

(b) all proceeds of any such Mortgage Certificates purchased or repurchased pursuant to the Trust Agreement; and

(c) all other amounts required to be deposited therein pursuant to the applicable Trust Agreement.

On or prior to each Distribution Date, the Securities Administrator will cause to be deposited into the Payment Account for distribution by the Paying Agent to Certificateholders of Certificates backed by Mortgage Certificates all amounts allocable to the Pool Distribution Amount for such Distribution Date.

If the Securities Administrator or the Trustee deposits in the Certificate Account for a Series any amount not required to be deposited therein, the Securities Administrator may at any time withdraw such amount from such account for itself or the Trustee, as applicable. Funds on deposit in the Certificate Account may be invested in Eligible Investments maturing in general not later than the business day preceding the next Distribution Date. In the event that an election has been made to treat the Trust Estate (or one or more segregated pools of assets therein) with respect to a Series as a REMIC, no such Eligible Investments will be sold or disposed of at a gain prior to maturity unless the Securities Administrator has received an opinion of counsel or other evidence satisfactory to it that such sale or disposition will not cause the Trust Estate (or segregated pool of assets) to be subject to the tax on "prohibited transactions" imposed by Code Section 860F(a)(1), otherwise subject the Trust Estate (or segregated pool of assets) to tax, or cause the Trust Estate (or any segregated pool of assets) to fail to qualify as a REMIC while any Certificates of the related Series are outstanding. Except as otherwise specified in the applicable prospectus supplement, all income and gain realized from any such investment will be for the account of the Securities Administrator as additional compensation and all losses from any such investment will be deposited by the Securities Administrator out of its own funds to the Certificate Account immediately as realized.

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The Securities Administrator is permitted, from time to time, to make withdrawals from the Certificate Account for the following purposes, to the extent permitted in the applicable Trust Agreement:

(a) to pay to itself the applicable Securities Administrator Fee;

(b) to reimburse itself or the Trustee (or in certain cases the Depositor) for certain expenses or indemnities incurred by and recoverable by or reimbursable to itself or the Trustee, as applicable, or any reimbursement amounts owed to itself or the Trustee, as applicable;

(c) to pay to the Depositor or the Sponsor with respect to each Mortgage Certificate that has been repurchased by the Depositor or the Sponsor, all amounts received thereon and not distributed as of the date as of which the purchase price of such Mortgage Certificate was determined;

(d) to pay to itself any interest earned on or investment income earned with respect to funds in the Certificate Account (all such interest or income to be withdrawn not later than the next Distribution Date);

(e) to remit funds to the Paying Agent;

(f) to withdraw from the Certificate Account any amount deposited in such account that was not required to be deposited therein; and

(g) to clear and terminate the Certificate Account.

A paying agent (the "Paying Agent"), which may be the Securities Administrator or the Trustee, will be appointed pursuant to the Trust Agreement to make distributions to Certificateholders of a Series. The Trustee may remove or replace the Paying Agent, other than Wells Fargo Bank, for so long as Wells Fargo Bank is acting as the Securities Administrator. Wells Fargo Bank, as Securities Administrator, will, on or prior to each Distribution Date, deposit in immediately available funds in an account designated by the Paying Agent, which may be the Certificate Account if Wells Fargo Bank is also acting as Paying Agent (the "Payment Account"), the amount required to be distributed to the Certificateholders on such Distribution Date. Funds on deposit in the Payment Account may be invested in Eligible Investments, as directed by the Securities Administrator. All income and gain realized from any such investment will be for the account of the Securities Administrator or such other party identified in the applicable prospectus supplement as additional compensation and all losses from any such investment will be deposited by such party out of its own funds to the Payment Account immediately as realized. Any fee payable to the Paying Agent will be paid by the Securities Administrator.

The Trustee will cause any Paying Agent that is not the Trustee or the Securities Administrator to execute and deliver to the Trustee an instrument in which such Paying Agent agrees with the Trustee that such Paying Agent will:

(i) hold all amounts deposited with it by the Securities Administrator for distribution to Certificateholders in trust for the benefit of Certificateholders until such amounts are distributed to Certificateholders or otherwise disposed of as provided in the Trust Agreement;

(ii) give the Trustee notice of any default by the Securities Administrator in remitting any required amount;

(iii) at any time during the continuance of any such default, upon written request to the Trustee, forthwith pay to the Trustee all amounts held in trust by such Paying Agent; and

(iv) if necessary in order to comply with the requirements of Regulation AB (17 C.F.R. 229), provide to the Securities Administrator the assessment of compliance by such entity with the servicing criteria set forth in Item 1122(d) of Regulation AB (17 C.F.R. 229.1122) applicable to its duties and the related attestation reports.

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Reports to Certificateholders

The Securities Administrator will prepare and make available via the internet to Certificateholders of record of each applicable Series of Certificates backed by Mortgage Certificates a Monthly Report setting forth the following information, if applicable:

(i) the applicable record date and interest accrual period (if any) for calculating the distribution and the actual Distribution Date for the distribution;

(ii) the amount of such distribution allocable to principal of the related Mortgage Certificates and the amount of such distribution allocable to interest on the related Mortgage Certificates;

(iii) if the distribution to Certificateholders is less than the full amount that would be distributable if there were sufficient funds available, the amount of the shortfall, the allocation of the shortfall between principal and interest and the aggregate amount of unpaid shortfalls with respect to the applicable Distribution Date and all prior Distribution Dates;

(iv) the amount of principal and interest paid on each Class of Certificates and the principal balance of each Class of Certificates prior to and after giving effect to the distributions of principal on the Distribution Date;

(v) the amount of the aggregate Securities Administrator Fees (if any) and other compensation paid to the Securities Administrator;

(vi) to each holder of a Certificate entitled to the benefits of payments under any form of credit enhancement or from any reserve fund:

(a) the amounts so distributed under any such form of credit enhancement or from any such reserve fund on the applicable Distribution Date; and

(b) the amount of coverage remaining under any such form of credit enhancement and the balance in any such reserve fund, after giving effect to any payments thereunder and other amounts charged thereto on the Distribution Date;

(vii) any payments made or accrued relating to credit enhancement provided by a party, identifying the general purpose of the payments and the party receiving the payments;

(viii) the Pass-Through Rate (if any) for each Class of Certificates;

(ix) the aggregate amount of realized losses applied to the Mortgage Certificates as of the related underlying Distribution Date and the amount of such losses allocated to each Class of Certificates;

(x) any expenses or indemnification amounts paid by the related Trust Estate, the specific purpose of each payment and the parties to whom these payments are made;

(xi) the total principal balance of the Mortgage Certificates as of the previous Distribution Date and the related Distribution Date and the weighted average Mortgage Certificate Pass-Through Rate;

(xii) the beginning and ending balances of the Certificate Account for a Series;

(xiii) any material breaches of representations and warranties relating to the Mortgage Certificates or material breaches of transaction covenants;

(xiv) the amount of excess cash flow, if any, for the related Distribution Date; and

(xv) whether any exchanges of Exchangeable REMIC Certificates and Exchangeable Certificates have taken place since the preceding Distribution Date and, if applicable, the class designations, principal balances or notional amounts, Pass-Through Rates, and any interest and/or principal paid, including any shortfalls allocated, with respect to any Classes of Certificates (or Mortgage Certificates, if applicable) that were received by

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Certificateholders (or the certificateholder of the Mortgage Certificates, if applicable) as a result of such exchange.

In addition, the Securities Administrator will make available (a) the Monthly Report for the Mortgage Certificates for the related underlying Distribution Date, as described under "The Pooling and Servicing Agreement--Reports to Certificateholders" and (b) any information specific to the Classes of Certificates offered by the applicable prospectus supplement. Within a reasonable period of time after the end of each calendar year, the Paying Agent will, upon request, furnish (or cause to be furnished) a report to each Certificateholder of record at any time during such calendar year such information as required by the Code and applicable regulations thereunder to enable Certificateholders to prepare their tax returns. In the event that an election has been made to treat the Trust Estate (or one or more segregated pools of assets therein) as a REMIC, the Trustee will be required to sign the federal and applicable state and local income tax returns of the REMIC (which will be prepared by the Securities Administrator). See "Material Federal Income Tax Consequences--Federal Income Tax Consequences for REMIC Certificates--Administrative Matters."

List of Certificateholders

The Trust Agreement for each applicable Series will require the Securities Administrator or other entity acting as certificate registrar to provide access to the most current list of names and addresses of Certificateholders of such Series to any group of five or more Certificateholders who advise the Securities Administrator or other entity acting as certificate registrar in writing that they desire to communicate with other Certificateholders with respect to their rights under the Trust Agreement or under the Certificates.

Events of Default

Events of Default under the Trust Agreement for a Series include (i) any failure by the Securities Administrator to make a required deposit which continues unremedied for three business days after receipt by the Securities Administrator of written notice of such failure by the Trustee for such Series, or to the Securities Administrator and the Trustee by the holders of Certificates of such Series having voting rights allocated to such Certificates ("Voting Interests") aggregating not less than 25% of the Voting Interests represented by all Certificates for such Series; (ii) any failure by the Securities Administrator duly to observe or perform in any material respect any other of its covenants or agreements in the Trust Agreement, or any material breach by the Securities Administrator of its representations and warranties made in the Trust Agreement resulting in a loss to the Depositor or the related Trust Estate, which continues unremedied for 60 days after the giving of written notice of such failure to the Securities Administrator by the Trustee or the Depositor, or to the Securities Administrator and the Trustee by the holders of Certificates aggregating not less than 25% of the Voting Interests represented by all of the Certificates for such Series, or which continues unremedied for a lesser number of days set forth in the applicable Trust Agreement in the case of a failure to perform any covenants or agreements relating to the requirements of Regulation AB (17 C.F.R. 229) and (iii) certain events of insolvency, readjustment of debt, marshaling of assets and liabilities or similar proceedings and certain actions by the Securities Administrator indicating its insolvency, reorganization or inability to pay its obligations.

Upon the occurrence of an Event of Default under the Trust Agreement for a Series, the Trustee will be required pursuant to the applicable Trust Agreement to (a) give prompt notice to each Rating Agency of the Event of Default and (b) within 45 days after the occurrence of any Event of Default known to the Trustee, give written notice thereof to Certificateholders of a Series, unless such Event of Default shall have been cured or waived within said 45 day period.

Rights Upon Event of Default

So long as an Event of Default remains unremedied under the Trust Agreement for a Series, the Trustee for such Series or holders of Certificates of such Series evidencing not less than 66 2/3% of the Voting Interests in the Trust Estate for such Series may terminate all of the rights and obligations of the Securities Administrator under the Trust Agreement and in and to the Mortgage Certificates (other than the Securities Administrator's right to recovery of the aggregate Securities Administrator Fees due prior to the date of termination and other expenses pursuant to the terms of the Trust Agreement, which rights the Securities Administrator will retain under all circumstances), whereupon

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the Trustee will succeed to all the responsibilities, duties and liabilities of the Securities Administrator under the Trust Agreement and will be entitled to monthly compensation not to exceed the aggregate Securities Administrator Fees together with the other compensation to which the Securities Administrator is entitled under the Trust Agreement. In the event that the Trustee is unwilling or unable so to act, it may select, pursuant to the public bid procedure described in the applicable Trust Agreement, or petition a court of competent jurisdiction to appoint, a housing and home finance institution, bank or mortgage servicing institution with a net worth of at least $10,000,000 to act as successor to the Securities Administrator under the provisions of the Trust Agreement; provided however, that until such a successor Securities Administrator is appointed and has assumed the responsibilities, duties and liabilities of the Securities Administrator under the Trust Agreement, the Trustee shall continue as the successor to the Securities Administrator as described above. In the event such public bid procedure is utilized, the successor would be entitled to compensation in an amount equal to the aggregate Securities Administrator Fees, together with the other compensation to which the Securities Administrator is entitled under the Trust Agreement, and the Securities Administrator would be entitled to receive the net profits, if any, realized from the sale of its rights and obligations under the Trust Agreement. The Trustee or the successor Securities Administrator will be entitled to be reimbursed from the predecessor Securities Administrator (or the Trust if the predecessor Securities Administrator is unable to fulfill its obligations under the Trust Agreement) for all costs associated with the transfer of securities administration.

During the continuance of any Event of Default under the Trust Agreement for a Series, the Trustee for such Series will have the right to take action to enforce its rights and remedies and to protect and enforce the rights and remedies of the Certificateholders of such Series, and holders of Certificates evidencing not less than 25% of the Voting Interests for such Series may direct the time, method and place of conducting any proceeding for any remedy available to the Trustee or exercising any trust or power conferred upon the Trustee. However, the Trustee will not be under any obligation to pursue any such remedy or to exercise any of such trusts or powers unless such Certificateholders have offered the Trustee reasonable security or indemnity against the cost, expenses and liabilities which may be incurred by the Trustee thereby. Also, the Trustee may decline to follow any such direction if the Trustee determines that the action or proceeding so directed may not lawfully be taken or would involve it in personal liability or be unjustly prejudicial to the non-assenting Certificateholders.

No Certificateholder of a Series, solely by virtue of such holder's status as a Certificateholder, will have any right under the Trust Agreement for such Series to institute any proceeding with respect to the Trust Agreement, unless such holder previously has given to the Trustee for such Series written notice of default and unless the holders of Certificates evidencing not less than 25% of the Voting Interests for such Series have made written request upon the Trustee to institute such proceeding in its own name as Trustee thereunder and have offered to the Trustee reasonable indemnity and the Trustee for 60 days has neglected or refused to institute any such proceeding.

Amendment

Each Trust Agreement may be amended by the Depositor, the Securities Administrator and the Trustee without the consent of the Certificateholders, (i) to cure any ambiguity or mistake, (ii) to correct or supplement any provision therein that may be inconsistent with any other provision therein or in this prospectus or the applicable prospectus supplement, (iii) to modify, eliminate or add to any of its provisions to such extent as shall be necessary to maintain the qualification of the related Trust Estate (or one or more segregated pools of assets therein) as a REMIC at all times that any Certificates are outstanding or to avoid or minimize the risk of the imposition of any tax on such Trust Estate pursuant to the Code that would be a claim against such Trust Estate, provided that the Trustee has received an opinion of counsel to the effect that such action is necessary or desirable to maintain such qualification or to avoid or minimize the risk of the imposition of any such tax and such action will not, as evidenced by such opinion of counsel, adversely affect in any material respect the interests of any Certificateholder, (iv) to conform the obligations of the parties under the Trust Agreement, if necessary, to comply with the requirements of Regulation AB (17 C.F.R. 229), (v) to change the timing and/or nature of deposits into the Certificate Account, provided that such change will not, as evidenced by an opinion of counsel, adversely affect in any material respect the interests of any Certificateholder, (vi) to add to, modify or eliminate any provisions therein restricting transfers of the Certificates of the related Series provided that the Depositor has determined in its sole discretion that any such modifications to the Trust Agreement will neither adversely affect the ratings on such Certificates nor give rise to a risk that the applicable REMIC or any Certificateholders will be subject to a tax caused by a transfer to a non-permitted transferee, (vii) to make certain provisions with respect to the denominations of, and

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the manner of payments on, certain Classes of Certificates initially retained by the Depositor or an affiliate, or (viii) to make any other provisions with respect to matters or questions arising under such Trust Agreement that are not inconsistent with the provisions thereof, provided that such action will not, as evidenced by an opinion of counsel, adversely affect in any material respect the interests of the Certificateholders of the related Series. Notwithstanding the foregoing, such action described in clause (v) or (viii) will not be considered to adversely affect in any material respect the interest of Certificateholders and no opinion of counsel to that effect will be required if each Rating Agency rating the Certificates states in writing that such action would not result in the downgrading or withdrawal of the ratings then assigned to the Certificates. The Trust Agreement may also be amended by the Depositor, the Securities Administrator and the Trustee with the consent of the holders of Certificates evidencing interests aggregating not less than 66 2/3% of the Voting Interests evidenced by the Certificates of each Class affected thereby, for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of such Trust Agreement or of modifying in any manner the rights of the Certificateholders; provided, however, that no such amendment may (a) reduce in any manner the amount of, or delay the timing of, any payments received on or with respect to Mortgage Certificates that are required to be distributed on any Certificates, without the consent of the holder of such Certificate, (b) adversely affect in any material respect the interests of the holders of a Class of Certificates of a Series in a manner other than that set forth in (a) above without the consent of the holders of Certificates aggregating not less than 66 2/3% of the Voting Interests evidenced by such Class, or (c) reduce the aforesaid percentage of Certificates of any Class, the holders of which are required to consent to such amendment, without the consent of the holders of all Certificates of such Class affected then outstanding. Notwithstanding the foregoing, the Trustee will not consent to any such amendment if such amendment would subject the Trust Estate (or any segregated pool of assets therein) to tax or cause the Trust Estate (or any segregated pool of assets therein) to fail to qualify as a REMIC.

Termination; Optional Purchase of Mortgage Certificates

The obligations created by the Trust Agreement for a Series of Certificates will terminate on the Distribution Date following the final payment or other liquidation of the last Mortgage Certificate subject thereto. In no event, however, will the trust created by the Trust Agreement continue beyond the expiration of 21 years from the death of the last survivor of certain persons named in such Trust Agreement. For each applicable Series of Certificates, the Paying Agent will give written notice of termination of the Trust Agreement to each Certificateholder, and the final distribution will be made only upon surrender and cancellation of the Certificates at an office or agency appointed by the Depositor and specified in the notice of termination.

If so specified in the applicable prospectus supplement, the Trust Agreement for a Series of Certificates may permit, but not require, the Depositor, the Sponsor of such Series or such other party as is specified in the applicable prospectus supplement, to purchase from the Trust Estate for such Series all remaining Mortgage Certificates (or one or more groups of Mortgage Certificates if specified in the applicable prospectus supplement), and thereby effect an early retirement of the applicable Series of Certificates (or in the case of the optional purchase of one or more, but less than all, groups of Mortgage Certificates, the Certificates relating to such group or groups), at a price equal to the sum of (a) the unpaid principal balance of each Mortgage Certificate in the applicable group or groups plus (b) the fair market value of other property in the Trust Estate (or the related group or groups, if specified in the applicable prospectus supplement) plus accrued and unpaid interest. However, for so long as the purchasing party is subject to regulation by the OCC, the FDIC, the Federal Reserve or the OTS, the purchasing party may exercise its purchase option only if the aggregate fair market value of the Mortgage Certificates is greater than or equal to the purchase price described in the preceding sentence. If applicable, this right to purchase all remaining Mortgage Certificates of a Series (or one or more groups of Mortgage Certificates of such Series, if specified in the applicable prospectus supplement) may be exercised on any Distribution Date when the aggregate principal balance of the applicable Mortgage Certificates is less than 10% of the aggregate unpaid principal balance of the applicable Mortgage Certificates as of the Cut-Off Date for such Series or a lower percentage specified in the applicable prospectus supplement.

In the event that such party has caused the related Trust Estate (or any segregated pool of assets therein) to be treated as a REMIC, any such purchase will be effected only pursuant to a "qualified liquidation" as defined in Code
Section 860F(a)(4)(A) and, if the Trust Estate is liquidated other than in the manner specified in the Trust Agreement, the receipt by the Trustee and the Securities Administrator of an opinion of counsel or other evidence that such other liquidation method (i) will constitute a "qualified liquidation" of the Trust Estate within the meaning

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of Code Section 860F(a)(4)(A) and (ii) will not cause the Trust Estate (or any segregated pool of assets) to fail to qualify as a REMIC. The exercise of such right will effect early retirement of the Certificates of that Series (or in the case of the optional purchase of one or more, but less than all, groups of Mortgage Certificates, the Certificates relating to such group or groups).

In addition, the Depositor of the Underlying Loans has the right to repurchase all remaining Underlying Loans in the underlying trust estate and thereby effect early retirement of the Mortgage Certificates, subject to the aggregate scheduled principal balance of such Underlying Loans at the time of repurchase being less than 10% (or other percentage specified in the applicable prospectus supplement) of the aggregate unpaid principal balance of the Underlying Loans as of the underlying cut-off date. Upon the Depositor effecting such repurchase with respect to the underlying trust estate, the Securities Administrator will distribute amounts received in respect of the Mortgage Certificates in connection with such repurchase to the Certificateholders as described in the applicable prospectus supplement on the related Distribution Date. The proceeds from any such distribution may not be sufficient to distribute the full amount to which each Class of Certificates is entitled if the amount received on the Mortgage Certificates is less than the outstanding principal balance thereof plus all accrued and unpaid interest thereon. See "Pooling and Servicing Agreement--Termination; Optional Purchase of Mortgage Loans."

The Securities Administrator

General

The securities administrator (the "Securities Administrator") with respect to each Series of Certificates issued by a Trust containing Mortgage Certificates will be Wells Fargo Bank. See "The Sponsor." Wells Fargo Bank conducts its securities administration services at its offices in Columbia, Maryland. Its address there is 9062 Old Annapolis Road, Columbia, Maryland 21045-1951 and its telephone number is (410) 884-2000. The Securities Administrator generally will
(a) be responsible under each Trust Agreement for providing general administrative services for the Trust Estate for any Series issued by a Trust containing Mortgage Certificates, including, among other things, (i) oversight of payments received on Mortgage Certificates, (ii) monitoring the amounts on deposit in various trust accounts, (iii) calculation of the amounts payable to Certificateholders on each Distribution Date, (iv) preparation of periodic reports to the Certificateholders with respect to the foregoing matters, (v) preparation of federal and applicable state and local tax and information returns and (vi) preparation of reports, if any, required under the Exchange Act and (b) maintain any insurance policy or other form of credit support that may be required with respect to any such Series. The Securities Administrator will also perform additional duties as described in the applicable Trust Agreement. The Securities Administrator may be entitled to receive the Securities Administrator Fee or other compensation, as more fully described in the applicable prospectus supplement. The Securities Administrator may subcontract with any entity the obligations of the Securities Administrator under any Trust Agreement. The Securities Administrator will remain primarily liable for any such contractor's performance in accordance with the applicable Trust Agreement. The Securities Administrator may be released from its obligations in certain circumstances.

The Securities Administrator will be required to pay certain expenses incurred in connection with the administration of a Trust Estate containing Mortgage Certificates, which will generally include the fees and disbursements of any custodian, the fees of the Trustee or co-trustee, fees due to the independent accountants and expenses incurred in connection with distributions and reports to Certificateholders. Certain of these expenses will be reimbursable to the Securities Administrator pursuant to the terms of the applicable Trust Agreement. Expenses that are reimbursable to the Securities Administrator include, but are not limited to, legal expenses incurred in connection with the prosecution or defense of any legal action (including any such expenses incurred by the Trustee) and certain taxes incurred by the Securities Administrator. Any loss to the applicable Trust Estate as a result of such reimbursement will be allocated first to the Subordinated Certificates of the related Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable prospectus supplement.

The Securities Administrator may not resign from its obligations and duties under the Trust Agreement for a Series, except (i) upon the appointment of a successor and the receipt by the Trustee of a letter from each Rating Agency rating the affected Series of Certificates that its resignation and the appointment of a successor will not result in a downgrade of such Certificates,
(ii) upon its determination that its duties thereunder are no longer

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permissible under applicable law or (iii) in the case of an assignment of its rights and delegation or its duties described below. No such resignation will become effective until the Trustee for such Series or a successor Securities Administrator has assumed the Securities Administrator's responsibilities, duties, liabilities and obligations under the Trust Agreement. If the Securities Administrator resigns for any of the foregoing reasons and the Trustee is unable or unwilling to assume responsibility for its duties under the Trust Agreement, it may appoint another institution to so act as described under "The Trust Agreement--Rights Upon Event of Default."

The Trust Agreement will also provide that neither the Securities Administrator nor any subcontractor, nor any director, officer, employee or agent of any of them, will be under any liability to a Trust Estate containing Mortgage Certificates or the related Certificateholders, for the taking of any action or for refraining from the taking of any action in good faith pursuant to such Trust Agreement, or for errors in judgment; provided, however, that neither the Securities Administrator, any subcontractor, nor any such person will be protected against any liability that would otherwise be imposed by reason of willful misfeasance, bad faith or gross negligence in the performance of his or its duties or by reason of reckless disregard of his or its obligations and duties thereunder. The Trust Agreement will further provide that the Securities Administrator, any subcontractor, and any director, officer, employee or agent of either of them shall be entitled to indemnification by the applicable Trust Estate and will be held harmless against any loss, liability or expense incurred in connection with the performance of their duties and obligations and any legal action relating to the applicable Trust Agreement, the Certificates or the Mortgage Certificates of the related Series, other than any loss, liability or expense incurred by reason of willful misfeasance, bad faith or gross negligence in the performance of his or its duties thereunder or by reason of reckless disregard of his or its obligations and duties thereunder. In addition, the Trust Agreement will provide that the Securities Administrator will not be under any obligation to appear in, prosecute or defend any legal action unless such action is related to its duties under the Trust Agreement and, in its opinion, does not involve it in any expense or liability. The Securities Administrator may, however, in its discretion, undertake any such action deemed by it necessary or desirable with respect to the Trust Agreement and the rights and duties of the parties thereto and the interests of the Certificateholders thereunder if the Certificateholders offer the Securities Administrator reasonable security or indemnity against the costs, expenses and liabilities that may be incurred. In such event, the legal expenses and costs of such action and any liability resulting therefrom will be expenses, costs and liabilities of the Trust Estate and the Securities Administrator will be entitled to be reimbursed therefor out of the Certificate Account, and any loss to the Trust Estate arising from such right of reimbursement will be allocated first to the Subordinated Certificates of the related Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable Trust Agreement.

Any person into which the Securities Administrator may be merged or consolidated, or any person resulting from any merger, conversion or consolidation to which the Securities Administrator is a party, or any person succeeding to the business through the transfer of substantially all of its assets or all assets relating to such business, or otherwise, of the Securities Administrator will be the successor of the Securities Administrator under the Trust Agreement for each applicable Series provided that such successor or resulting entity has a net worth of not less than $15,000,000.

The Securities Administrator also has the right, without the prior written consent of the Trustee, to assign its rights and delegate its duties and obligations under the Trust Agreement for each applicable Series; provided that, if the Securities Administrator desires to be released from its obligations under the Trust Agreement, (i) the purchaser executes and delivers to the Depositor and the Trustee an agreement, in form and substance reasonably satisfactory to the Trustee, which contains an assumption by such purchaser or transferee of the due and punctual performance and observance of each covenant and condition to be performed or observed by the Securities Administrator under the Trust Agreement from and after the date of such agreement; and (ii) each applicable Rating Agency's rating of any Certificates for such Series in effect immediately prior to such assignment, sale or transfer would not be qualified, downgraded or withdrawn as a result of such assignment, sale or transfer and the Certificates are not reasonably likely to be placed on credit review status by any such Rating Agency. The Securities Administrator will be released from its obligations under the Trust Agreement upon any such assignment and delegation, except that the Securities Administrator will remain liable for all liabilities and obligations incurred by it prior to the time that the conditions contained in clauses (i) and (ii) above are met. In addition, the Securities Administrator shall have the right, without the written consent of the Trustee, to delegate to, subcontract with, authorize, or appoint an affiliate of the Securities Administrator to perform and carry out any duties, covenants or obligations to be performed and carried out by the Securities Administrator under the Trust Agreement and is required to delegate, subcontract, authorize or appoint to an affiliate of the Securities Administrator any duties, covenants or obligations to be performed and

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carried out by the Securities Administrator to the extent that such duties, covenants or obligations are to be performed in any state or states in which the Securities Administrator is not authorized to do business as a foreign corporation but in which the affiliate is so authorized.

The Trustee or a successor Securities Administrator is entitled to be reimbursed for its costs in effecting a securities administration transfer from the Securities Administrator. In the event that the predecessor Securities Administrator fails to reimburse the Trustee or successor Securities Administrator, as applicable, the Trustee or successor Securities Administrator will be entitled to reimbursement from the assets of the related Trust.

Securities Administration Experience and Procedures of Wells Fargo Bank

For a description of the securities administration experience and procedures of Wells Fargo Bank, see "Servicing of the Mortgage Loans--Master Servicing Experience and Procedures of Wells Fargo Bank."

Evidence as to Compliance

The Securities Administrator will deliver or make available annually, on or before the date specified in the applicable Trust Agreement, as applicable, an officer's certificate stating that (i) a review of the activities of the Securities Administrator during the preceding calendar year and of performance under the applicable Trust Agreement has been made under the supervision of such officer, and (ii) to the best of such officer's knowledge, based on such review, the Securities Administrator has fulfilled all its obligations under the applicable Trust Agreement in all material respects throughout such year, or, if there has been a failure to fulfill any such obligation in any material respect, specifying each such failure known to such officer and the nature and status of the failure.

In addition, the Securities Administrator and any other party that participates in the servicing and administration of the Mortgage Certificates and other assets comprising a Trust Estate will deliver annually an Assessment of Compliance. Each party that is required to deliver an Assessment of Compliance will also be required to simultaneously deliver an Attestation Report. See "Servicing of the Mortgage Loans--Evidence as to Compliance."

The Trustee

The trustee under each Trust Agreement (together with the trustee under each Pooling and Servicing Agreement, each a "Trustee") will be named in the applicable prospectus supplement. The commercial bank or trust company serving as Trustee may have normal banking relationships with the Depositor or any of its affiliates. The Securities Administrator will perform certain duties and functions normally performed by the Trustee.

The Trustee will be entitled to a fee in connection with its responsibilities under the Trust Agreement. The amount and manner of payment of the fee will be specified in the applicable prospectus supplement.

The Trust Agreement will provide that the Trustee will be entitled to reimbursement from the related Trust Estate for all reasonable expenses, disbursements and advances incurred or made by it in accordance with the provisions of such Trust Agreement to the extent permitted by Treasury regulations Section 1.860G-1(b)(3), which allows reimbursement for "unanticipated expenses," except (i) for any such expense, disbursement or advance arising from the Trustee's gross negligence, bad faith or willful misconduct and (ii) for any routine ongoing expenses incurred by the Trustee in the ordinary course of its duties. Any loss to the Trust Estate as a result of such reimbursement will be allocated first to the Subordinated Certificates of a Series before being allocated to the related Senior Certificates, or if such Series does not contain Subordinated Certificates, pro rata among the various Classes of Certificates or in another manner specified in the applicable prospectus supplement.

The Trustee and any director, officer, employee or agent of the Trustee will be entitled to indemnification by the applicable Trust Estate and held harmless against any loss, liability or expense (including reasonable attorney's fees)
(a) incurred in connection with any claim or legal action relating to (i) the Trust Agreement, (ii) the Certificates, or (iii) the performance of any of the Trustee's duties under the Trust Agreement, unless the loss, liability or expense was incurred by reason of willful misfeasance, bad faith or gross negligence in the performance of any of the

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Trustee's duties under the Trust Agreement and (b) resulting from any tax or information return which was prepared by, or should have been prepared by, the Securities Administrator.

The Trustee may resign at any time, in which event the Securities Administrator will be obligated to appoint a successor trustee. The Securities Administrator may also remove the Trustee if the Trustee ceases to be eligible to act as Trustee under the Trust Agreement, if the Trustee becomes incapable of acting as Trustee, if the Trustee becomes insolvent or in order to change the situs of the Trust Estate for state tax reasons. Upon becoming aware of such circumstances, the Securities Administrator will become obligated to appoint a successor trustee. The Trustee may also be removed at any time by the holders of Certificates evidencing not less than 51% of the Voting Interests in the applicable Trust Estate, except that, any Certificate registered in the name of the Depositor, the Securities Administrator or any affiliate thereof will not be taken into account in determining whether the requisite Voting Interest in such Trust Estate necessary to effect any such removal has been obtained. Any resignation and removal of the Trustee, and the appointment of a successor trustee, will not become effective until acceptance of such appointment by the successor trustee. The Trustee, and any successor trustee, will be required to
(a) be a corporation or association having its principal office in a state and city acceptable to the Depositor, organized and doing business under the laws of such state or the United States of America, authorized under such laws to exercise corporate trust powers having a combined capital and surplus of at least $50,000,000, or will be a member of a bank holding system, the aggregate combined capital and surplus of which is at least $50,000,000, provided that the Trustee's and any such successor trustee's separate capital and surplus shall at all times be at least the amount specified in Section 310(a)(2) of the Trust Indenture Act of 1939, (b) be subject to supervision or examination by federal or state authorities and (c) have a credit rating or be otherwise acceptable to the Rating Agencies.

In the event the predecessor trustee has resigned or is removed for cause, any costs associated with the appointment of a successor trustee are required to be paid by the predecessor and, if not paid, will be reimbursed to the successor trustee from the assets of the related Trust. Notwithstanding the foregoing, if the predecessor has been removed without cause, any costs associated with the appointment of a successor trustee will be reimbursed to the party incurring such costs from the assets of the related Trust.

CERTAIN LEGAL ASPECTS OF THE MORTGAGE LOANS

The following discussion contains summaries of certain legal aspects of mortgage loans which are general in nature. Because such legal aspects are governed by applicable state law (which laws may differ substantially), the summaries do not purport to be complete or to reflect the laws of any particular state, nor to encompass the laws of all states in which the security for the Mortgage Loans is situated. The summaries are qualified in their entirety by reference to the applicable federal and state laws governing the Mortgage Loans.

General

The Mortgage Loans will, in general, be secured by either first mortgages or first deeds of trust, depending upon the prevailing practice in the state in which the underlying property is located. A mortgage creates a lien upon the real property described in the mortgage. There are two parties to a mortgage:
the mortgagor, who is the borrower (or, in the case of a Mortgage Loan secured by a property that has been conveyed to an inter vivos revocable trust, the settlor of such trust); and the mortgagee, who is the lender. In a mortgage instrument state, the mortgagor delivers to the mortgagee a note or bond evidencing the loan and the mortgage. Although a deed of trust is similar to a mortgage, a deed of trust has three parties: a borrower called the trustor (similar to a mortgagor), a lender called the beneficiary (similar to a mortgagee), and a third-party grantee called the trustee. Under a deed of trust, the borrower grants the property, irrevocably until the debt is paid, in trust, generally with a power of sale, to the trustee to secure payment of the loan. The trustee's authority under a deed of trust and the mortgagee's authority under a mortgage are governed by the express provisions of the deed of trust or mortgage, applicable law, and, in some cases, with respect to the deed of trust, the directions of the beneficiary.

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Condominiums

Certain of the Mortgage Loans may be loans secured by condominium units. The condominium building may be a multi-unit building or buildings, or a group of buildings whether or not attached to each other, located on property subject to condominium ownership. Condominium ownership is a form of ownership of real property as to which each owner is entitled to the exclusive ownership and possession of his or her individual condominium unit. The owner also owns a proportionate undivided interest in all parts of the condominium building (other than the other individual condominium units) and all areas or facilities, if any, for the common use of the condominium units. The condominium unit owners appoint or elect the condominium association to govern the affairs of the condominium.

Cooperatives

Certain of the Mortgage Loans may be cooperative loans. The Cooperative either owns all the real property that comprises the project, including the land and the apartment building comprised of separate dwelling units and common areas or leases the land generally by a long term ground lease and owns the apartment building. The Cooperative is directly responsible for project management and, in most cases, payment of real estate taxes and hazard and liability insurance. If there is a blanket mortgage on the property and/or underlying land, as is generally the case, the Cooperative, as project mortgagor, is also responsible for meeting these mortgage obligations. Ordinarily, the Cooperative incurs a blanket mortgage in connection with the construction or purchase of the Cooperative's apartment building. The interest of the occupants under proprietary leases or occupancy agreements to which the Cooperative is a party are generally subordinate to the interest of the holder of the blanket mortgage in that building. See "Risk Factors-Collateral Securing Cooperative Loans May Diminish in Value" in this prospectus.

The Cooperative is owned by tenant stockholders who, through ownership of stock, shares or membership certificates in the corporation, receive proprietary leases or occupancy agreements which confer exclusive rights to occupy specific units. Generally, a tenant stockholder of a Cooperative must make a monthly payment to the Cooperative representing such tenant stockholder's pro rata share of the Cooperative's payments for its blanket mortgage, real property taxes, maintenance expenses and other capital or ordinary expenses. An ownership interest in a Cooperative and accompanying rights is financed through a cooperative share loan evidenced by a promissory note and secured by a security interest in the occupancy agreement or proprietary lease and in the related cooperative shares. The lender takes possession of the share certificate and a counterpart of the proprietary lease or occupancy agreement, and typically a financing statement covering the proprietary lease or occupancy agreement and the cooperative shares is filed in the appropriate state and local offices to perfect the lender's interest in its collateral. Subject to the limitations discussed below, upon default of the tenant stockholder, the lender may sue for judgment on the promissory note, dispose of the collateral at a public or private sale or otherwise proceed against the collateral or tenant stockholder as an individual as provided in the security agreement covering the assignment of the proprietary lease or occupancy agreement and the pledge of cooperative shares.

Foreclosure

Foreclosure of a mortgage is generally accomplished by judicial action. Generally, the action is initiated by the service of legal pleadings upon all parties having an interest of record in the real property. Delays in completion of the foreclosure occasionally may result from difficulties in locating necessary parties defendant. When the mortgagee's right of foreclosure is contested, the legal proceedings necessary to resolve the issue can be time-consuming. After the completion of a judicial foreclosure proceeding, the court may issue a judgment of foreclosure and appoint a receiver or other officer to conduct the sale of the property. In some states, mortgages may also be foreclosed by advertisement, pursuant to a power of sale provided in the mortgage. Foreclosure of a mortgage by advertisement is essentially similar to foreclosure of a deed of trust by non-judicial power of sale.

Foreclosure of a deed of trust is generally accomplished by a non-judicial trustee's sale under a specific provision in the deed of trust that authorizes the trustee to sell the property to a third party upon any default by the borrower under the terms of the note or deed of trust. In certain states, such foreclosure also may be accomplished by judicial action in the manner provided for foreclosure of mortgages. In some states, the trustee must record a notice of default and send a copy to the borrower-trustor and to any person who has recorded a request for a copy of

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a notice of default and notice of sale. In addition, the trustee must provide notice in some states to any other individual having an interest of record in the real property, including any junior lienholders. If the deed of trust is not reinstated within any applicable cure period, a notice of sale must be posted in a public place and, in most states, published for a specified period of time in one or more newspapers. In addition, some state laws require that a copy of the notice of sale be posted on the property and sent to all parties having an interest of record in the property.

In some states, the borrower-trustor has the right to reinstate the loan at any time following default until shortly before the trustee's sale. In general, the borrower, or any other person having a junior encumbrance on the real estate, may, during a reinstatement period, cure the default by paying the entire amount in arrears plus the costs and expenses incurred in enforcing the obligation. Certain state laws control the amount of foreclosure expenses and costs, including attorneys' fees, which may be recovered by a lender.

In case of foreclosure under either a mortgage or a deed of trust, the sale by the receiver or other designated officer, or by the trustee, is a public sale. However, because of the difficulty a potential buyer at the sale would have in determining the exact status of title and because the physical condition of the property may have deteriorated during the foreclosure proceedings, it is uncommon for a third party to purchase the property at the foreclosure sale. Rather, it is common for the lender to purchase the property from the trustee or receiver for an amount equal to the unpaid principal amount of the note, accrued and unpaid interest and the expenses of foreclosure. Thereafter, subject to the right of the borrower in some states to remain in possession during the redemption period, the lender will assume the burdens of ownership, including obtaining hazard insurance and making such repairs at its own expense as are necessary to render the property suitable for sale. The lender commonly will obtain the services of a real estate broker and pay the broker a commission in connection with the sale of the property. Depending upon market conditions, the ultimate proceeds of the sale of the property may not equal the lender's investment in the property. Any loss may be reduced by the receipt of mortgage insurance proceeds, if any, or by judicial action against the borrower for the deficiency, if such action is permitted by law. See "--Anti-Deficiency Legislation and Other Limitations on Lenders" below.

Certain states, such as Mississippi, may limit the right of foreclosure under certain conditions in the event of natural disasters, such as hurricanes.

Foreclosure on Shares of Cooperatives

The cooperative shares owned by the tenant-stockholder and pledged to the lender are, in almost all cases, subject to restrictions on transfer as set forth in the Cooperative's Certificate of Incorporation and By-laws, as well as in the proprietary lease or occupancy agreement, and may be cancelled by the Cooperative for failure by the tenant-stockholder to pay rent or other obligations or charges owed by such tenant-stockholder, including mechanics' liens against the Cooperative apartment building incurred by such tenant-stockholder. The proprietary lease or occupancy agreement generally permits the Cooperative to terminate such lease or agreement in the event an obligor fails to make payments or defaults in the performance of covenants required thereunder. Typically, the lender and the Cooperative enter into a recognition agreement which establishes the rights and obligations of both parties in the event of a default by the tenant-stockholder on its obligations under the proprietary lease or occupancy agreement. A default by the tenant-stockholder under the proprietary lease or occupancy agreement will usually constitute a default under the security agreement between the lender and the tenant-stockholder.

The recognition agreement generally provides that, in the event that the tenant-stockholder has defaulted under the proprietary lease or occupancy agreement, the Cooperative will take no action to terminate such lease or agreement until the lender has been provided an opportunity to cure the default. The recognition agreement typically provides that if the proprietary lease or occupancy agreement is terminated, the Cooperative will recognize the lender's lien against proceeds from a sale of the Cooperative apartment, subject, however, to the Cooperative's right to sums due under such proprietary lease or occupancy agreement. The total amount owed to the Cooperative by the tenant-stockholder, which the lender generally cannot restrict and does not monitor, could reduce the value of the collateral below the outstanding principal balance of the cooperative loan and accrued and unpaid interest thereon.

Recognition agreements also provide that in the event of a foreclosure on a cooperative loan, the lender must obtain the approval or consent of the Cooperative as required by the proprietary lease before transferring the cooperative shares or assigning the proprietary lease. Generally, the lender is not limited by the agreement in any rights it may have to dispossess the tenant-stockholders.

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Foreclosure on the cooperative shares is accomplished by a sale in accordance with the provisions of Article 9 of the Uniform Commercial Code (the "UCC") and the security agreement relating to those shares. Article 9 of the UCC requires that a sale be conducted in a "commercially reasonable" manner. Whether a foreclosure sale has been conducted in a "commercially reasonable" manner will depend on the facts in each case. In determining commercial reasonableness, a court will look to the notice given the debtor and the method, manner, time, place and terms of the foreclosure. Generally, a sale conducted according to the usual practice of banks selling similar collateral will be considered reasonably conducted.

Article 9 of the UCC provides that the proceeds of the sale will be applied first to pay the costs and expenses of the sale and then to satisfy the indebtedness secured by the lender's security interest. The recognition agreement, however, generally provides that the lender's right to reimbursement is subject to the right of the Cooperative corporation to receive sums due under the proprietary lease or occupancy agreement. If there are proceeds remaining, the lender must account to the tenant-stockholder for the surplus. Conversely, if a portion of the indebtedness remains unpaid, the tenant-stockholder is generally responsible for the deficiency. See "--Anti-Deficiency Legislation and Other Limitations on Lenders" below.

Leaseholds

Mortgage Loans may be secured by a mortgage on a ground lease. Leasehold mortgages are subject to certain considerations not associated with mortgage loans secured by the fee estate of the mortgagor. The most significant of these consideration is that the ground lease creating the leasehold estate could terminate, leaving the leasehold mortgagee without its security. The ground lease may terminate, if among other reasons, the ground lessee breaches or defaults in its obligations under the ground lease or there is a bankruptcy of the ground lessee or the ground lessor. This possibility may be minimized if the ground lease contains certain provisions protective of the mortgagee, but the ground leases that secure Mortgage Loans may not contain some of these protective provisions, and mortgages may not contain the other protection discussed in the next paragraph. Protective ground lease provisions include the right of the leasehold mortgagee to receive notices from the ground lessor of any defaults by the mortgagor; the right to cure those defaults, with adequate cure periods; if a default is not susceptible of cure by the leasehold mortgagee, the right to acquire the leasehold estate through foreclosure or otherwise; the ability of the ground lease to be assigned to and by the leasehold mortgagee or purchaser at a foreclosure sale and for the simultaneous release of the ground lessee's liabilities under the new lease; and the right of the leasehold mortgagee to enter into a new ground lease with the ground lessor on the same terms and conditions as the old ground lease upon a termination.

In addition to the preceding protections, a leasehold mortgagee may require that the ground lease or leasehold mortgage prohibit the ground lessee from treating the ground lease as terminated in the event of the ground lessor's bankruptcy and rejection of the ground lease by the trustee for the debtor-ground lessor. As further protection, a leasehold mortgage may provide for the assignment of the debtor-ground lessee's right to reject a lease pursuant to Section 365 of the Bankruptcy Code, although the enforceability of that clause has not been established. Without the protections described in the preceding paragraph, a leasehold mortgagee may lose the collateral securing its leasehold mortgage. In addition, terms and conditions of a leasehold mortgage are subject to the terms and conditions of the ground lease. Although certain rights given to a ground lessee can be limited by the terms of a leasehold mortgage, the rights of a ground lessee or a leasehold mortgagee with respect to, among other things, insurance, casualty and condemnation will be governed by the provisions of the ground lease.

Rights of Redemption

In some states, after sale pursuant to a deed of trust and/or foreclosure of a mortgage, the borrower and certain foreclosed junior lienors are given a statutory period in which to redeem the property from the foreclosure sale. In most states where the right of redemption is available, statutory redemption may occur upon payment of the foreclosure purchase price, accrued interest and taxes. In some states, the right to redeem is an equitable right. The effect of a right of redemption is to delay the ability of the lender to sell the foreclosed property. The exercise of a right of redemption would defeat the title of any purchaser at a foreclosure sale, or of any purchaser from the lender subsequent to judicial foreclosure or sale under a deed of trust. Consequently, the practical effect of the redemption right is to force the lender to maintain the property and pay the expenses of ownership until the redemption period has run.

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Anti-Deficiency Legislation, the Bankruptcy Code and Other Limitations on Lenders

Certain states have imposed statutory prohibitions which limit the remedies of a beneficiary under a deed of trust or a mortgagee under a mortgage. In some states, statutes limit the right of the beneficiary or mortgagee to obtain a deficiency judgment against the borrower following foreclosure or sale under a deed of trust. A deficiency judgment would be a personal judgment against the former borrower equal in most cases to the difference between the net amount realized upon the public sale of the real property and the amount due to the lender. Other statutes require the beneficiary or mortgagee to exhaust the security afforded under a deed of trust or mortgage by foreclosure in an attempt to satisfy the full debt before bringing a personal action against the borrower. Finally, other statutory provisions limit any deficiency judgment against the former borrower following a judicial sale to the excess of the outstanding debt over the fair market value of the property at the time of public sale. The purpose of these statutes is generally to prevent a beneficiary or a mortgagee from obtaining a large deficiency judgment against the former borrower as a result of low or no bids at the judicial sale.

Generally, Article 9 of the UCC governs foreclosure on cooperative shares and the related proprietary lease or occupancy agreement and foreclosure on the beneficial interest in a land trust. Some courts have interpreted Section 9-504 of the UCC to prohibit a deficiency award unless the creditor establishes that the sale of the collateral (which, in the case of a Mortgage Loan secured by shares of a cooperative, would be such shares and the related proprietary lease or occupancy agreement) was conducted in a commercially reasonable manner.

A Servicer generally will not be required under the applicable Underlying Servicing Agreement to pursue deficiency judgments on the Mortgage Loans even if permitted by law.

In addition to anti-deficiency and related legislation, numerous other federal and state statutory provisions, including the United States Bankruptcy Code, 11 U.S.C. Sections 101 et seq. (the "Bankruptcy Code"), and state laws affording relief to debtors may interfere with or affect the ability of a secured mortgage lender to obtain payment of a mortgage loan, to realize upon collateral and/or enforce a deficiency judgment. For example, under the Bankruptcy Code, virtually all actions (including foreclosure actions and deficiency judgment proceedings) are automatically stayed upon the filing of a bankruptcy petition, and, usually, no interest or principal payments are made during the course of the bankruptcy case. Foreclosure of an interest in real property of a debtor in a case under the Bankruptcy Code can typically occur only if the bankruptcy court vacates the stay, an action, the court may be reluctant to take, particularly if the debtor has the prospect of restructuring his or her debts and the mortgage collateral is not deteriorating in value. The delay and the consequences thereof caused by such automatic stay can be significant. Also, under the Bankruptcy Code, the filing of a petition in bankruptcy by or on behalf of a junior lienor (a subordinate lender secured by a mortgage on the property) may stay a senior lender from taking action to foreclose.

A homeowner may file for relief under the Bankruptcy Code under any of three different chapters of the Bankruptcy Code. Under Chapter 7, the assets of the debtor are liquidated and a lender secured by a lien may "bid in" (i.e., bid up to the amount of the debt) at the sale of the asset. See "--Foreclosure." A homeowner may also file for relief under Chapter 11 of the Bankruptcy Code and reorganize his or her debts through his or her reorganization plan. Alternatively, a homeowner may file for relief under Chapter 13 of the Bankruptcy Code and address his or her debts in a rehabilitation plan. (Chapter 13 is often referred to as the "wage earner chapter" or "consumer chapter" because most individuals seeking to restructure their debts file for relief under Chapter 13 rather than Chapter 11).

The Bankruptcy Code permits a mortgage loan that is secured by property that does not consist solely of the debtor's principal residence to be modified without the consent of the lender provided certain substantive and procedural safeguards are met. Under the Bankruptcy Code, the lender's security interest may be reduced to the then-current value of the property as determined by the court if the value is less than the amount due on the loan, thereby leaving the lender as a general unsecured creditor for the difference between the value of the collateral and the outstanding balance of the mortgage loan. A borrower's unsecured indebtedness will typically be discharged in full upon payment of a substantially reduced amount. Other modifications to a mortgage loan may include a reduction in the amount of each scheduled payment, which reduction may result from a reduction in the rate of interest, an alteration of the repayment schedule, an extension of the final maturity date, and/or a reduction in the outstanding balance of the secured portion of the loan. In certain circumstances, subject to the court's approval, a debtor in a case under Chapter 11 of the Bankruptcy Code may have the power to grant liens senior to the lien of a mortgage.

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A reorganization plan under Chapter 11 and a rehabilitation plan under Chapter 13 of the Bankruptcy Code may each allow a debtor to cure a default with respect to a mortgage loan on such debtor's residence by paying arrearages over a period of time and to deaccelerate and reinstate the original mortgage loan payment schedule, even though the lender accelerated the loan and a final judgment of foreclosure had been entered in state court (provided no sale of the property had yet occurred) prior to the filing of the debtor's petition under the Bankruptcy Code. Under a Chapter 13 plan, curing of defaults must be accomplished within the five year maximum term permitted for repayment plans, such term commencing when repayment plan becomes effective, while defaults may be cured over a longer period of time under a Chapter 11 plan of reorganization.

Generally, a repayment plan in a case under Chapter 13 and a plan of reorganization under Chapter 11 may not modify the claim of a mortgage lender if the borrower elects to retain the property, the property is the borrower's principal residence and the property is the lender's only collateral. Certain courts have allowed modifications when the mortgage loan is secured both by the debtor's principal residence and by collateral that is not "inextricably bound" to the real property, such as appliances, machinery, or furniture.

The general protection for mortgages secured only by the debtor's principal residence is not applicable in a case under Chapter 13 if the last payment on the original payment schedule is due before the final date for payment under the debtor's Chapter 13 plan (which date could be up to five years after the debtor emerges from bankruptcy). Under several recently decided cases, the terms of such a loan can be modified in the manner described above. While these decisions are contrary to the holding in a prior case by a senior appellate court, it is possible that the later decisions will become the accepted interpretation in view of the language of the applicable statutory provision. If this interpretation is adopted by a court considering the treatment in a Chapter 13 repayment plan of a Mortgage Loan, it is possible that the Mortgage Loan could be modified.

State statutes and general principles of equity may also provide a mortgagor with means to halt a foreclosure proceeding or sale and to force a restructuring of a mortgage loan on terms a lender would not otherwise accept.

In a bankruptcy or similar proceeding of a mortgagor, action may be taken seeking the recovery, as a preferential transfer or on other grounds, of any payments made by the mortgagor under the related mortgage loan prior to the bankruptcy or similar proceeding. Payments on long-term debt may be protected from recovery as preferences if they are payments in the ordinary course of business made on debts incurred in the ordinary course of business or if the value of the collateral exceeds the debt at the time of payment. Whether any particular payment would be protected depends upon the facts specific to a particular transaction.

A trustee in bankruptcy, in some cases, may be entitled to collect its costs and expenses in preserving or selling the mortgaged property ahead of a payment to the lender. Moreover, the laws of certain states also give priority to certain tax and mechanics liens over the lien of a mortgage. Under the Bankruptcy Code, if the court finds that actions of the mortgagee have been unreasonable and inequitable, the lien of the related mortgage may be subordinated to the claims of unsecured creditors.

The Code provides priority to certain tax liens over the lien of the mortgage.

In addition, substantive requirements are imposed upon mortgage lenders in connection with the origination and the servicing of mortgage loans by numerous federal and some state consumer protection laws. These laws include the federal Trust-in-Lending Act, Real Estate Settlement Procedures Act, Equal Credit Opportunity Act, Fair Credit Billing Act, Fair Credit Reporting Act, and related statutes. These federal laws impose specific statutory liabilities upon lenders who originate mortgage loans and who fail to comply with the provisions of the applicable laws. In some cases, this liability may affect assignees of the Mortgage Loans.

Forfeiture for Drug, RICO and Money Laundering Violations

Federal law provides that property purchased or improved with assets derived from criminal activity or otherwise tainted, or used in the commission of certain offenses, can be seized and ordered forfeited to the United States of America. The offenses which can trigger such a seizure and forfeiture include, among others, violations of the Racketeer Influenced and Corrupt Organizations Act, the Bank Secrecy Act, the anti-money laundering laws and regulations, including the USA Patriot Act of 2001 and the regulations issued thereunder, as well as the narcotic drug laws. In many instances, the United States may seize the property even before a conviction occurs.

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In the event of a forfeiture proceeding, a lender may be able to establish its interest in the property by proving that (i) its mortgage was executed and recorded before the commission of the illegal conduct from which the assets used to purchase or improve the property were derived or before the commission of any other crime upon which the forfeiture is based, or (ii) the lender, at the time of the execution of the mortgage, "did not know or was reasonably without cause to believe that the property was subject to forfeiture." However, there can be no assurance that such a defense will be successful.

Homeowners Protection Act of 1998

The Homeowners Protection Act of 1998 ("HOPA") provides for certain disclosure and termination requirements for primary mortgage insurance ("PMI"). The termination provisions of HOPA apply only to mortgage loans relating to single-family primary residences originated on or after July 29, 1999. Such termination provisions govern when a mortgagor may cancel the requirement to maintain PMI and when the requirement to maintain PMI is automatically terminated. In general, voluntary termination is permitted and automatic termination occurs when the principal balance of the mortgage loan is reduced to 80% or 78%, respectively, of the original property value. The disclosure requirements of HOPA vary depending on whether the mortgage loan was originated before or after July 29, 1999. Such disclosure requirements include notification of the circumstances whereby a mortgagor may cancel PMI, the date when PMI automatically terminates and servicer contact information. In addition, HOPA provides that no later than 30 days after cancellation or termination of PMI, the servicer shall provide written notification that such PMI is terminated and no further payments are due or payable. Any servicer, mortgagee or mortgage insurer that violates provisions of HOPA is subject to possible liability which includes, but is not limited to, actual damages, statutory damages and reasonable attorney's fees.

Texas Home Equity Loans

Generally, any "cash-out" refinance or other non-purchase money transaction
(except for rate/term refinance loans and certain other narrow exceptions)
secured by a Texas resident's principal residence is subject to the provisions set forth in Section 50(a)(6) of Article XVI of the Constitution of Texas and its implementing statutes and regulations (the "Texas Home Equity Laws"). The Texas Home Equity Laws provide for certain disclosure requirements, caps on allowable fees, required loan closing procedures and other restrictions. Failure, inadvertent or otherwise, to comply with any requirement may render the Mortgage Loan unenforceable and/or the lien on the Mortgaged Property voidable unless cured within 60 days after the borrower provides notice of the defect to the lender. Because mortgage loans which are subject to the Texas Home Equity Laws can be foreclosed only pursuant to court order, rather than non-judicial foreclosure as is available for other types of mortgage loans in Texas, delays and increased losses may result in connection with foreclosures of such loans. If a court were to find that any requirement of the Texas Home Equity Laws was not complied with, the court could refuse to allow foreclosure to proceed, declare the lien on the Mortgaged Property to be invalid, and/or require the originating lender or the holder of the note to forfeit some or all principal and interest of the related Mortgage Loan. Title insurance generally available on such Mortgage Loans may exclude coverage for some of the risks described in this paragraph.

Servicemembers Civil Relief Act and Similar Laws

Generally, under the terms of the Servicemembers Civil Relief Act (the "Relief Act"), a borrower who enters military service after the origination of such borrower's Mortgage Loan (including a borrower who is a member of the National Guard or is in reserve status at the time of the origination of the Mortgage Loan and is later called to active duty) may not be charged interest, including fees and charges, above an annual rate of 6% during the period of such borrower's active duty status. In addition to adjusting the interest, the lender must forgive any such interest in excess of 6% per annum, unless a court or administrative agency orders otherwise upon application of the lender. It is possible that such action could have an effect, for an indeterminate period of time, on the ability of the Servicer to collect full amounts of interest on certain of the Mortgage Loans in a Trust Estate. Any shortfall in interest collections resulting from the application of the Relief Act or any amendment thereto could result in losses to the holders of the Certificates of the related Series. Further, the Relief Act imposes limitations which would impair the ability of the Servicer to foreclose on an affected Mortgage Loan during the borrower's period of active duty status. Thus, in the event that such a Mortgage Loan goes into default, there may be delays and losses occasioned by the inability to realize upon the Mortgaged Property in a timely fashion. In addition, the Relief Act provides broad discretion for a court to modify a Mortgage Loan upon application of the mortgagor. Certain states have enacted

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comparable legislation which may lead to the modification of a Mortgage Loan or interfere with or affect the ability of the Servicer to timely collect payments of principal and interest on, or to foreclose on, Mortgage Loans of borrowers in such states who are active or reserve members of the armed services or national guard. For example, California has enacted legislation providing protection substantially similar to that provided by the Relief Act to California national guard members called up for active service by the Governor or President and reservists called to active duty.

Environmental Considerations

A lender may be subject to unforeseen environmental risks when taking a security interest in real or personal property. Property subject to such a security interest may be subject to federal, state, and local laws and regulations relating to environmental protection. Such laws may regulate, among other things: emissions of air pollutants; discharges of wastewater or storm water; generation, transport, storage or disposal of hazardous waste or hazardous substances; operation, closure and removal of underground storage tanks; removal and disposal of asbestos-containing materials; management of electrical or other equipment containing polychlorinated biphenyls ("PCBs"). Failure to comply with such laws and regulations may result in significant penalties, including civil and criminal fines. Under the laws of certain states, environmental contamination on a property may give rise to a lien on the property to ensure the availability and/or reimbursement of cleanup costs. Generally all subsequent liens on such property are subordinated to such a lien and, in some states, even prior recorded liens are subordinated to such liens ("Superliens"). In the latter states, the security interest of the Trustee in a property that is subject to such a Superlien could be adversely affected.

Under the federal Comprehensive Environmental Response, Compensation and Liability Act, as amended ("CERCLA"), and under state law in certain states, a secured party which takes a deed in lieu of foreclosure, purchases a mortgaged property at a foreclosure sale, operates a mortgaged property or undertakes certain types of activities that may constitute management of the mortgaged property may become liable in certain circumstances for the costs of remedial action ("Cleanup Costs") if hazardous wastes or hazardous substances have been released or disposed of on the property. Such Cleanup Costs may be substantial and could exceed the value of the property and the aggregate assets of the owner or operator. CERCLA imposes strict, as well as joint and several liability for environmental remediation and/or damage costs on several classes of "potentially responsible parties," including current "owners and/or operators" of property, irrespective of whether those owners or operators caused or contributed to contamination on the property. In addition, owners and operators of properties that generate hazardous substances that are disposed of at other "off-site" locations may held strictly, jointly and severally liable for environmental remediation and/or damages at those off-site locations. Many states also have laws that are similar to CERCLA. Liability under CERCLA or under similar state law could exceed the value of the property itself as well as the aggregate assets of the property owner.

The law is unclear as to whether and under what precise circumstances cleanup costs, or the obligation to take remedial actions, could be imposed on a secured lender such as the Trust Estate. Under the laws of some states and under CERCLA, a lender may be liable as an "owner or operator" for costs of addressing releases or threatened releases of hazardous substances on a mortgaged property if such lender or its agents or employees have "participated in the management" of the operations of the borrower, even though the environmental damage or threat was caused by a prior owner or current owner or operator or other third party. Excluded from CERCLA's definition of "owner or operator," is a person "who without participating in the management of . . . [the] facility, holds indicia of ownership primarily to protect his security interest" (the "secured-creditor exemption"). This exemption for holders of a security interest such as a secured lender applies only to the extent that a lender seeks to protect its security interest in the contaminated facility or property. Thus, if a lender's activities begin to encroach on the actual management of such facility or property, the lender faces potential liability as an "owner or operator" under CERCLA. Similarly, when a lender forecloses and takes title to a contaminated facility or property, the lender may incur potential CERCLA liability in various circumstances including, among others, when it holds the facility or property as an investment (including leasing the facility or property to a third party), fails to market the property in a timely fashion or fails to properly address environmental conditions at the property or facility.

The Resource Conservation and Recovery Act, as amended ("RCRA"), contains a similar secured-creditor exemption for those lenders who hold a security interest in a petroleum underground storage tank ("UST") or in real estate containing a UST, or that acquire title to a petroleum UST or facility or property on which such a UST is

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located. As under CERCLA, a lender may lose its secured-creditor exemption and be held liable under RCRA as a UST owner or operator if such lender or its employees or agents participate in the management of the UST. In addition, if the lender takes title to or possession of the UST or the real estate containing the UST, under certain circumstances the secured-creditor exemption may be deemed to be unavailable.

A decision in May 1990 of the United States Court of Appeals for the Eleventh Circuit in United States v. Fleet Factors Corp. very narrowly construed CERCLA's secured-creditor exemption. The court's opinion suggested that a lender need not have involved itself in the day-to-day operations of the facility or participated in decisions relating to hazardous waste to be liable under CERCLA, rather, liability could attach to a lender if its involvement with the management of the facility were broad enough to support the inference that the lender had the capacity to influence the borrower's treatment of hazardous waste. The court added that a lender's capacity to influence such decisions could be inferred from the extent of its involvement in the facility's financial management. A subsequent decision by the United States Court of Appeals for the Ninth Circuit in In re Bergsoe Metal Corp., apparently disagreeing with, but not expressly contradicting, the Fleet Factors court, held that a secured lender had no liability absent "some actual management of the facility" on the part of the lender.

Court decisions have taken varying views of the scope of the secured-creditor exemption, leading to administrative and legislative efforts to provide guidance to lenders on the scope of activities that would trigger CERCLA and/or RCRA liability. Until recently, these efforts have failed to provide substantial guidance.

On September 30, 1996, however, the President signed into law the Asset Conservation Lender Liability and Deposit Insurance Protection Act of 1996 (the "Asset Conservation Act"). The Asset Conservation Act was intended to clarify the scope of the secured-creditor exemption under both CERCLA and RCRA. The Asset Conservation Act more explicitly defined the kinds of "participation in management" that would trigger liability under CERCLA and specified certain activities that would not constitute "participation in management" or otherwise result in a forfeiture of the secured-creditor exemption prior to foreclosure or during a workout period. The Asset Conservation Act also clarified the extent of protection against liability under CERCLA in the event of foreclosure and authorized certain regulatory clarifications of the scope of the secured-creditor exemption for purposes of RCRA, similar to the statutory protections under CERCLA. However, since the courts have not yet had the opportunity to interpret the new statutory provisions, the scope of the additional protections offered by the Asset Conservation Act is not fully defined. It also is important to note that the Asset Conservation Act does not offer complete protection to lenders and that the risk of liability remains.

If a secured lender does become liable, it may be entitled to bring an action for contribution against the owner or operator who created the environmental contamination or against some other liable party, but that person or entity may be bankrupt or otherwise judgment-proof. It is therefore possible that cleanup or other environmental liability costs could become a liability of the Trust Estate and occasion a loss to the Trust Estate and to Certificateholders in certain circumstances. The new secured creditor amendments to CERCLA, also, would not necessarily affect the potential for liability in actions by either a state or a private party under other federal or state laws which may impose liability on "owners or operators" but do not incorporate the secured-creditor exemption.

Traditionally, residential mortgage lenders have not taken steps to evaluate whether hazardous wastes or hazardous substances are present with respect to any mortgaged property prior to the origination of the mortgage loan or prior to foreclosure or accepting a deed-in-lieu of foreclosure. Accordingly, neither the Depositor, Wells Fargo Bank nor the Wells Fargo Affiliates have made such evaluations prior to the origination of the Mortgage Loans, nor does Wells Fargo Bank or the Wells Fargo Affiliates require that such evaluations be made by originators who have sold the Mortgage Loans to Wells Fargo Bank. Neither the Depositor nor Wells Fargo Bank is required to undertake any such evaluations prior to foreclosure or accepting a deed-in-lieu of foreclosure. Neither the Depositor nor the Master Servicer makes any representations or warranties or assumes any liability with respect to: the environmental condition of such Mortgaged Property; the absence, presence or effect of hazardous wastes or hazardous substances on any Mortgaged Property; any casualty resulting from the presence or effect of hazardous wastes or hazardous substances on, near or emanating from such Mortgaged Property; the impact on Certificateholders of any environmental condition or presence of any substance on or near such Mortgaged Property; or the compliance of any Mortgaged Property with any environmental laws, nor is any agent, person or entity otherwise affiliated with the Depositor authorized or able to make any such representation, warranty or assumption of liability relative to any such Mortgaged Property. See "The Pooling and Servicing Agreement--Representations

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and Warranties" and "Servicing of the Mortgage Loans--Enforcement of Due-on-Sale Clauses; Realization Upon Defaulted Mortgage Loans" above.

"Due-on-Sale" Clauses

The forms of note, mortgage and deed of trust relating to Mortgage Loans may contain a "due-on-sale" clause permitting acceleration of the maturity of a loan if the borrower transfers its interest in the property. In recent years, court decisions and legislative actions placed substantial restrictions on the right of lenders to enforce such clauses in many states. However, effective October 15, 1982, Congress enacted the Garn-St Germain Depository Institutions Act of 1982 (the "Garn Act") which purports to preempt state laws which prohibit the enforcement of "due-on-sale" clauses by providing among other matters, that "due-on-sale" clauses in certain loans (which loans may include the Mortgage Loans) made after the effective date of the Garn Act are enforceable, within certain limitations as set forth in the Garn Act and the regulations promulgated thereunder. "Due-on-sale" clauses contained in mortgage loans originated by federal savings and loan associations or federal savings banks are fully enforceable pursuant to regulations of the Office of Thrift Supervision ("OTS"), as successor to the Federal Home Loan Bank Board ("FHLBB"), which preempt state law restrictions on the enforcement of such clauses. Similarly, "due-on-sale" clauses in mortgage loans made by national banks and federal credit unions are now fully enforceable pursuant to preemptive regulations of the Comptroller of the Currency and the National Credit Union Administration, respectively.

The Garn Act created a limited exemption from its general rule of enforceability for "due-on-sale" clauses in certain mortgage loans ("Window Period Loans") which were originated by non-federal lenders and made or assumed in certain states ("Window Period States") during the period, prior to October 15, 1982, in which that state prohibited the enforcement of "due-on-sale" clauses by constitutional provision, statute or statewide court decision (the "Window Period"). Though neither the Garn Act nor the OTS regulations actually names the Window Period States, Freddie Mac has taken the position, in prescribing mortgage loan servicing standards with respect to mortgage loans which it has purchased, that the Window Period States were: Arizona, Arkansas, California, Colorado, Georgia, Iowa, Michigan, Minnesota, New Mexico, Utah and Washington. Under the Garn Act, unless a Window Period State took action by October 15, 1985, the end of the Window Period, to further regulate enforcement of "due-on-sale" clauses in Window Period Loans, "due-on-sale" clauses would become enforceable even in Window Period Loans. Five of the Window Period States (Arizona, Minnesota, Michigan, New Mexico and Utah) have taken actions which restrict the enforceability of "due-on-sale" clauses in Window Period Loans beyond October 15, 1985. The actions taken vary among such states.

By virtue of the Garn Act, a Servicer may generally be permitted to accelerate any Mortgage Loan which contains a "due-on-sale" clause upon transfer of an interest in the property subject to the mortgage or deed of trust. With respect to any Mortgage Loan secured by a residence occupied or to be occupied by the borrower, this ability to accelerate will not apply to certain types of transfers, including (i) the granting of a leasehold interest which has a term of three years or less and which does not contain an option to purchase, (ii) a transfer to a relative resulting from the death of a borrower, or a transfer where the spouse or children become an owner of the property in each case where the transferee(s) will occupy the property, (iii) a transfer resulting from a decree of dissolution of marriage, legal separation agreement or from an incidental property settlement agreement by which the spouse becomes an owner of the property, (iv) the creation of a lien or other encumbrance subordinate to the lender's security instrument which does not relate to a transfer of rights of occupancy in the property (provided that such lien or encumbrance is not created pursuant to a contract for deed), (v) a transfer by devise, descent or operation of law on the death of a joint tenant or tenant by the entirety, (vi) a transfer into an inter vivos trust in which the borrower is the beneficiary and which does not relate to a transfer of rights of occupancy; and (vii) other transfers as set forth in the Garn Act and the regulations thereunder. Regulations promulgated under the Garn Act also prohibit the imposition of a prepayment penalty upon the acceleration of a loan pursuant to a due-on-sale clause. The extent of the effect of the Garn Act on the average lives and delinquency rates of the Mortgage Loans cannot be predicted. See "Prepayment and Yield Considerations."

Applicability of Usury Laws

Title V of the Depository Institutions Deregulation and Monetary Control Act of 1980, enacted in March 1980 ("Title V"), provides that state usury limitations shall not apply to certain types of residential first mortgage loans

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originated by certain lenders after March 31, 1980. The OTS as successor to the FHLBB is authorized to issue rules and regulations and to publish interpretations governing implementation of Title V. The statute authorized any state to reimpose interest rate limits by adopting before April 1, 1983, a law or constitutional provision which expressly rejects application of the federal law. Fifteen states have adopted laws reimposing or reserving the right to reimpose interest rate limits. In addition, even where Title V is not so rejected, any state is authorized to adopt a provision limiting certain other loan charges.

The Depositor will represent and warrant in the Pooling and Servicing Agreement to the Trustee for the benefit of Certificateholders that all Mortgage Loans are originated in full compliance with applicable state laws, including usury laws. See "The Pooling and Servicing Agreement--Assignment of Mortgage Loans to the Trustee."

Enforceability of Certain Provisions

Standard forms of note, mortgage and deed of trust generally contain provisions obligating the borrower to pay a late charge if payments are not timely made and in some circumstances may provide for prepayment fees or penalties if the obligation is paid prior to maturity. In certain states, there are or may be specific limitations upon late charges which a lender may collect from a borrower for delinquent payments. Certain states also limit the amounts that a lender may collect from a borrower as an additional charge if the loan is prepaid. Under the Pooling and Servicing Agreement, late charges and prepayment fees (to the extent permitted by law and not waived by the Servicer) will be retained by the Servicer as additional servicing compensation.

Courts have imposed general equitable principles upon foreclosure. These equitable principles are generally designed to relieve the borrower from the legal effect of defaults under the loan documents. Examples of judicial remedies that may be fashioned include judicial requirements that the lender undertake affirmative and expensive actions to determine the causes for the borrower's default and the likelihood that the borrower will be able to reinstate the loan. In some cases, courts have substituted their judgment for the lender's judgment and have required lenders to reinstate loans or recast payment schedules to accommodate borrowers who are suffering from temporary financial disability. In some cases, courts have limited the right of lenders to foreclose if the default under the mortgage instrument is not monetary, such as the borrower failing to adequately maintain the property or the borrower executing a second mortgage or deed of trust affecting the property. In other cases, some courts have been faced with the issue of whether federal or state constitutional provisions reflecting due process concerns for adequate notice require that borrowers under the deeds of trust receive notices in addition to the statutorily-prescribed minimum requirements. For the most part, these cases have upheld the notice provisions as being reasonable or have found that the sale by a trustee under a deed of trust or under a mortgage having a power of sale does not involve sufficient state action to afford constitutional protections to the borrower.

MATERIAL FEDERAL INCOME TAX CONSEQUENCES

The following discussion represents the opinion of Cadwalader, Wickersham & Taft LLP as to the anticipated material federal income tax consequences of the purchase, ownership and disposition of Certificates. The discussion below does not purport to address all federal income tax consequences that may be applicable to particular categories of investors, some of which may be subject to special rules. The authorities on which this discussion is based are subject to change or differing interpretations, and any such change or interpretation could apply retroactively. This discussion reflects the applicable provisions of the Code, as well as regulations (the "REMIC Regulations") promulgated by the U.S. Department of the Treasury. Investors should consult their own tax advisors in determining the federal, state, local and any other tax consequences to them of the purchase, ownership and disposition of Certificates.

If a Series of Certificates includes Exchangeable Certificates, each Class of Exchangeable Certificates will represent beneficial ownership of one or more interests in one or more REMIC regular interests. The applicable prospectus supplement will specify whether each Class of Exchangeable Certificates represents a proportionate or disproportionate interest in each underlying REMIC regular interest. The Exchangeable Certificates will be created, sold and administered pursuant to an arrangement that will be treated as a grantor trust under subpart E, Part 1 of subchapter J of the Code. The tax treatment of Exchangeable Certificates is discussed under "--Federal Income Tax Consequences for Exchangeable Certificates" below.

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For purposes of this discussion, where the applicable prospectus supplement provides for a Fixed Retained Yield with respect to the Mortgage Loans of a Series of Certificates, references to the Mortgage Loans will be deemed to refer to that portion of the Mortgage Loans held by the Trust Estate that does not include the Fixed Retained Yield. References to a "holder" or "Certificateholder" in this discussion generally mean the beneficial owner of a Certificate.

Federal Income Tax Consequences for REMIC Certificates

General

With respect to a particular Series of Certificates, an election may be made to treat the Trust Estate or one or more segregated pools of assets therein as one or more real estate mortgage investment conduits (each, a "REMIC") within the meaning of Section 860D of the Internal Revenue Code of 1986, as amended (the "Code"). A Trust Estate or a portion or portions thereof as to which one or more REMIC elections will be made will be referred to as a "REMIC Pool." For purposes of this discussion, Certificates of a Series as to which one or more REMIC elections are made are referred to as "REMIC Certificates" and will consist of one or more Classes of "Regular Certificates" and one Class of "Residual Certificates" in the case of each REMIC Pool. Qualification as a REMIC requires ongoing compliance with certain conditions. With respect to each Series of REMIC Certificates, Cadwalader, Wickersham & Taft LLP, counsel to the Depositor, has advised the Depositor that in the firm's opinion, assuming (i) the making of an appropriate election, (ii) compliance with the Pooling and Servicing Agreement, and (iii) compliance with any changes in the law, including any amendments to the Code or applicable Treasury regulations thereunder, each REMIC Pool will qualify as a REMIC. In such case, the Regular Certificates will be considered to be "regular interests" in the REMIC Pool and generally will be treated for federal income tax purposes as if they were newly originated debt instruments, and the Residual Certificates will be considered to be "residual interests" in the REMIC Pool. The prospectus supplement for each Series of Certificates will indicate whether one or more REMIC elections with respect to the related Trust Estate will be made, in which event references to "REMIC" or "REMIC Pool" herein shall be deemed to refer to each such REMIC Pool.

Status of REMIC Certificates

REMIC Certificates held by a domestic building and loan association will constitute "a regular or residual interest in a REMIC" within the meaning of Code Section 7701(a)(19)(C)(xi) in the same proportion that the assets of the REMIC Pool would be treated as "loans . . . secured by an interest in real property which is . . . residential real property" within the meaning of Code
Section 7701(a)(19)(C)(v) or as other assets described in Code Section 7701(a)(19)(C). REMIC Certificates held by a real estate investment trust will constitute "real estate assets" within the meaning of Code Section 856(c)(4)(A), and interest on the Regular Certificates and income with respect to Residual Certificates will be considered "interest on obligations secured by mortgages on real property or on interests in real property" within the meaning of Code
Section 856(c)(3)(B) in the same proportion that, for both purposes, the assets of the REMIC Pool would be so treated. If at all times 95% or more of the assets of the REMIC Pool qualify for each of the foregoing treatments, the REMIC Certificates will qualify for the corresponding status in their entirety. For purposes of Code Section 856(c)(4)(A), payments of principal and interest on the Mortgage Assets that are reinvested pending distribution to holders of REMIC Certificates qualify for such treatment.

Where two REMIC Pools are a part of a tiered structure they will be treated as one REMIC for purposes of the tests described above respecting asset ownership of more or less than 95%. In addition, if the assets of the REMIC include Buy-Down Loans, it is possible that the percentage of such assets constituting "loans . . . secured by an interest in real property which is . . . residential real property" for purposes of Code Section 7701(a)(19)(C)(v) may be required to be reduced by the amount of the related Buy-Down Funds. Regular Certificates will represent "qualified mortgages," within the meaning of Code
Section 860G(a)(3), for other REMICs. REMIC Certificates held by a regulated investment company will not constitute "Government securities" within the meaning of Code Section 851(b)(3)(A)(i). REMIC Certificates held by certain financial institutions will constitute an "evidence of indebtedness" within the meaning of Code Section 582(c)(1).

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Qualification as a REMIC

In order for the REMIC Pool to qualify as a REMIC, there must be ongoing compliance on the part of the REMIC Pool with the requirements set forth in the Code. The REMIC Pool must fulfill an asset test, which requires that no more than a de minimis portion of the assets of the REMIC Pool, as of the close of the third calendar month beginning after the "Startup Day" (which for purposes of this discussion is the date of issuance of the REMIC Certificates) and at all times thereafter, may consist of assets other than "qualified mortgages" and "permitted investments." The REMIC Regulations provide a safe harbor pursuant to which the de minimis requirement will be met if at all times the aggregate adjusted basis of the nonqualified assets is less than 1% of the aggregate adjusted basis of all the REMIC Pool's assets. An entity that fails to meet the safe harbor may nevertheless demonstrate that it holds no more than a de minimis amount of nonqualified assets. A REMIC Pool also must provide "reasonable arrangements" to prevent its residual interests from being held by "disqualified organizations" or agents thereof and must furnish applicable tax information to transferors or agents that violate this requirement. See "--Taxation of Residual Certificates--Tax-Related Restrictions on Transfer of Residual Certificates--Disqualified Organizations."

A qualified mortgage is any obligation that is principally secured by an interest in real property and that is either transferred to the REMIC Pool on the Startup Day or is either purchased by the REMIC Pool within a three-month period thereafter or represents an increase in the loan advanced to the obligor under its original terms, in each case pursuant to a fixed price contract in effect on the Startup Day. Qualified mortgages include whole mortgage loans, such as the Mortgage Loans, and, generally, certificates of beneficial interest in a grantor trust that holds mortgage loans and regular interests in another REMIC, such as lower-tier regular interests in a tiered REMIC or Mortgage Certificates held by a REMIC. The REMIC Regulations specify that loans secured by timeshare interests and shares held by a tenant stockholder in a cooperative housing corporation can be qualified mortgages. A qualified mortgage includes a qualified replacement mortgage, which is any property that would have been treated as a qualified mortgage if it were transferred to the REMIC Pool on the Startup Day and that is received either (i) in exchange for any qualified mortgage within a three-month period thereafter or (ii) in exchange for a "defective obligation" within a two-year period thereafter. A "defective obligation" includes (i) a mortgage in default or as to which default is reasonably foreseeable, (ii) a mortgage as to which a customary representation or warranty made at the time of transfer to the REMIC Pool has been breached,
(iii) a mortgage that was fraudulently procured by the mortgagor, and (iv) a mortgage that was not in fact principally secured by real property (but only if such mortgage is disposed of within 90 days of discovery). A Mortgage Loan that is "defective" as described in clause (iv) that is not sold or, if within two years of the Startup Day, exchanged, within 90 days of discovery, ceases to be a qualified mortgage after such 90-day period.

Permitted investments include cash flow investments, qualified reserve assets, and foreclosure property. A cash flow investment is an investment, earning a return in the nature of interest, of amounts received on or with respect to qualifi