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The following is an excerpt from a 10-K SEC Filing, filed by PENN OCTANE CORP on 11/10/2004.
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PENN OCTANE CORP - 10-K - 20041110 - EXHIBIT_10

January 13, 2004

FirstName LastName
Company
Company1
Address1
Address2
City , State Zip

RE: AMENDMENT - PROMISSORY NOTE ("NOTE") OF PENN OCTANE CORPORATION (THE
"COMPANY") CURRENTLY HELD BY YOU WITH A DUE DATE OF DECEMBER 15, 2003
AND RELATED AGREEMENTS AND INSTRUMENTS

Dear Holder Of The Promissory Notes:

Reference is made to the promissory note(s) which is currently held by you in connection with one or more of the following transactions with the Company:

i.) The promissory note(s) originally issued by the Company in connection with the private placement on or around December 17, 1999 (the "Original Notes"), as amended (the "Restructured Notes"), and/or

ii.) The promissory note(s) originally issued by the Company contemporaneously with the restructuring of the Original Notes (the "New Notes").

iii.) The promissory note originally issued in June 2002 for $200,000 and December 2002 for $300,000 (the "Additional Notes").

The Restructured Notes, the New Notes and the Additional Notes are collectively referred to as the "Promissory Notes" and all of the underlying agreements pertaining to the Promissory Notes, including the purchase agreement, the note agreement, the common stock purchase warrant agreement, the registration rights agreement, and all related amendments, if any, are collectively referred to as the "Original Documents".

The Promissory Notes, including unpaid interest were due and payable on December 15, 2003. The Company desires to extend the payment due date on the Promissory Notes until December 15, 2005 under the following conditions: (i) The principal amount of the Promissory Notes will be due in one balloon payment on December 15, 2005, except that the Promissory Notes may be repaid at any time without penalty in whole or in part at the sole option of the Company, (ii) the Company will continue to pay interest on the Promissory Notes at a rate of 16.50% per annum, payable quarterly, (iii) The Company will also extend the expiration date of the warrants currently held by you in connection with the original issuance of the Promissory Notes to December 15, 2008. In connection with the New Notes and Additional Notes, whereby the holders of those notes did not receive any warrants in connection with their investment, the Company will issue warrants under the


Amendment To Promissory Notes
January 13, 2004

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same terms and conditions of the warrants described herein, (iv) the Company agrees to continue to pay you a fee equal to 1.5% of the principal amount of the Promissory Notes which remain outstanding, if any, at the close of business on December 15, 2003, March 15, 2004, June 15, 2004, September 15, 2004, December 15, 2004, March 15, 2005, June 15, 2005, September 15, 2005 and December 15, 2005. In the case of the Additional Notes, the fee will continue to be 2.0%, (v) the Company will issue additional warrants to the holders of the Promissory Notes to purchase units in Rio Vista Energy Partners L.P., provided that the Company successfully completes the Spin-off. The warrants will granted based on 2,500 warrants for each $100,000 of Promissory Notes extended at the time this Amendment is executed and 2,500 warrants for each $100,000 of Promissory Notes outstanding on December 16, 2004, if any. The warrants will expire on December 15, 2008 and the exercise price will be based on a formula as described below, and (vi) the Company will provide the holders of the Promissory Notes with a letter confirmation from RZB regarding RZB's agreement to refrain from taking any action against certain assets of the Company until all the Promissory Notes have been fully repaid and the Company on a good faith basis will provide a perfected security interest in the US portion of its owned pipelines after the indebtedness of Cowboy and Tanner have been fully repaid.

The holders of the Promissory Notes are currently aware of the Company's efforts to complete the Spin-off as more fully described in the Company's Form 10-K for the year ended July 31, 2003, filed on November 3, 2003 and the Company's 10-Q for the quarter ended October 31, 2003, filed on December 17, 2003. In connection with the Spin-off, the Company will be required to obtain consents from the holders of the Promissory Notes to complete the Spin-off. This amendment will provide for the consent by the holders of the Promissory Notes for the Company to complete the Spin-off under the terms described below

The Company also desires to remove Investec as the collateral agent in connection with the Promissory Notes. This amendment will provide for consent by the holders of the Promissory Notes for the Company to replace Investec as collateral agent replacing them with The Law Offices of Kevin Finck, counsel to the Company.

This amendment will also provide for consent by the holders of the Promissory Notes for the collateral agent to immediately release 1,000,000 shares of common stock of the Company owned by Mr. Jerome Richter (the "Shares") and pledged as security in connection with the Promissory Notes upon the Company's perfection of security interest in certain assets as described below. The parties agree to establish a mutually agreeable escrow agent to hold the Shares.

For good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Company and you hereby agree that your Original Documents shall be, and hereby are, amended, effective from and after December 15, 2003, to the fullest extent necessary to effectuate the following:

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Amendment To Promissory Notes
January 13, 2004

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1. Promissory Notes. The Promissory Notes held by you are hereby amended to the full extent necessary to effectuate the following:

(a) Extend the payment due date from "December 15, 2003" to "December 15, 2005".
(b) Principal payments shall be due on December 15, 2005.
(c) The Promissory Notes may be repaid by the Company in whole or part at any time prior to December 15, 2005 without penalty.
(d) Payment of interest on the Promissory Notes outstanding at the rate of 16.50% per annum payable as follows: The December 15, 2003 payment which has yet to be made will be paid on the execution date of this Amendment and remaining quarterly interest will be paid on March 15, 2004, June 15, 2004, September 15, 2004, December 15, 2004, March 15, 2005, June 15, 2005, September 15, 2005 and December 15, 2005.

2. Additional Payment. The Company will pay to you a fee equal to 1.5% on the principal amount of your Promissory Notes which are outstanding on each of the following dates; December 15, 2003, March 15, 2004, June 15, 2004, September 15, 2004, December 15, 2004, March 15, 2005, June 15, 2005, September 15, 2005 and December 15, 2005. The fee will be payable in accordance with the interest payment dates described in 1(d) above. The fee is not due on any principal balance which is paid down during any of the interim periods. The fee payable for the Additional Notes is 2.0%.

3. Warrants. The Company will extend the expiration date on those warrants which you received in connection with the original issuance of the Promissory Notes and related amendments. The current expiration date on those warrants shall be changed from "December 15, 2006" to "December 15, 2008".

In connection with the above, the Company will issue to the holder of the New Notes and Additional Notes new warrants under the same terms and conditions of the warrants issued to the holders of the Restructured Notes.

4. Issuance of Rio Vista Warrants. In the event that the Spin-off is successfully completed by the Company (see 9. below), the Company agrees that the holders of the Promissory Notes shall be entitled to receive warrants to purchase units of Rio Vista under the following terms and conditions:

a. Holder of the Promissory Notes shall be entitled to receive 2,500 warrants to purchase units of Rio Vista for every $100,000 of principal of Promissory Notes extended,

b. Holder of the Promissory Notes shall be entitled to receive an

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Amendment To Promissory Notes
January 13, 2004

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additional 2,500 warrants to purchase units of Rio Vista for every $100,000 of principal of Promissory Notes outstanding at December 16, 2004,
c. Exercise price of all warrants will be based on the 1st qtly distribution paid by Rio Vista, annualized, to provide a 20% yield (example: Dividend $.25. Annualized $1.00, Exercise price $5.00),
d. The expiration date of warrants will be December 15, 2006,
e. The warrants will be callable by Rio Vista in the event that the annualized current dividend provides a 10% yield based on the average common unit trading price for 30 consecutive days,
f. Issuance of the warrants herein are only required if Rio Vista is successfully Spun-off. No additional obligation from the Company to the holder of the Promissory Notes if the Company does not complete the Spin-off of Rio Vista,

5. RZB Subordination. You hereby agree that the attached draft subordination letter from RZB is satisfactory (see Exhibit A) in connection with RZB's agreement to refrain from taking any action against certain assets of the Company until all the Promissory Notes have been fully repaid

6. Agreement Not To Pledge Assets: The Company agrees that it will not pledge any of its assets before or after the Spin-off occurs nor will it allow Rio Vista to pledge any of its assets without the consent of the Borrower and the holders of the Replacement Notes. The Company further agrees that it will on a good faith basis provide the holders of the Promissory Notes and the Replacement Notes a perfected security interest in the US portion of its owned pipelines, except that such perfection will not be attempted until the Cowboy and Tanner obligations have been fully repaid, expected to be no later than March 31, 2004. The Company is not responsible for any consents which cannot be obtained in connection with such perfection.

7. Collateral Agent. Investec will no longer serve as collateral agent in connection with the Promissory Notes and be replaced by "The Law Offices of Kevin Finck"

8. Release of Collateral. Upon the perfection of the security interest described in 6. above, the holders of the Promissory Notes hereby consent to the immediate release of 1,000,000 shares of common stock of the Company owned by Mr. Jerome Richter (the "Shares") and pledged as additional security in connection obligations owing by the Company under the Promissory Notes. In addition, the parties agree to determine a mutually agreeable escrow agent to retain custody of the Shares during the time that the Promissory Notes are outstanding.

9. Consent to Spin-off. The holders of the Promissory Notes hereby consent to the Company completing the Spin-off as more fully described in the Form 10 filed by Rio Vista Energy Partners L.P. ("Rio Vista") with the SEC, as amended, and

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Amendment To Promissory Notes
January 13, 2004

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as described in the Company's Form 10-K for the year ended July 31, 2003, and Form 10-Q for the quarter ended October 31, 2003 provided that the Spin-off provides for the following:

a. The Company or Rio Vista Energy Partners L.P. ("Rio Vista") will be prohibited from entering into any further agreement to pledge any of its pipeline or terminal assets until the Promissory Notes have been paid in full
b. Rio Vista will guaranty performance under the Promissory Notes
c. Rio Vista will be prohibited from making any distributions ("Distributions") to unitholders to the extent that any payments required as of the date of the Distribution have not been made.
d. The form of providing for the above conditions will be documented by the Company on a good faith basis

10. Philadelphia Brokerage Corporation. In connection with the restructuring of the Promissory Notes, the Company has agreed to pay Philadelphia Brokerage Corporation a fee of 1.5% of the total amount of Promissory Notes restructured and the total amount of Replacement Notes issued (see below). In addition, Philadelphia Brokerage Corporation will receive 10,000 warrants to purchase units in Rio Vista at the time this Amendment is executed and 10,000 additional warrants on December 16, 2004 (or a pro rata portion thereon based on the remaining principal amount of Promissory Notes and Replacement Notes outstanding at December 16, 2003 and the total amount of Promissory Notes and Replacements at the time this amendment is executed. The terms and conditions of the warrants will be the same as those issued to the holders of the Promissory Notes as described in 4. above.

11. Declining Noteholders. Notwithstanding anything to the contrary contained in your Original Documents, you hereby agree that, to the extent that any other holders of the Promissory Notes do not agree to this amendment letter by December 13, 2003 (collectively, the "Declining Promissory Noteholders"), the Company shall be entitled to repay such Declining Promissory Noteholders all amounts owing by the Company to such Declining Promissory Noteholders under their respective Original Documents without, by virtue thereof, in any way breaching or otherwise being in default of any of your Original Documents. Any such amounts paid, shall be excluded from the definition of "Financing" provided for in your Original Documents.

In addition to the above, to the extent that any amounts are required to be repaid in connection with Declining Noteholders, you hereby agree to allow the Company to obtain additional financing (the "Replacement Notes") equal to the amount of Promissory Notes repaid to the Declining Noteholders under the same

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Amendment To Promissory Notes
January 13, 2004

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terms and conditions outlined in this Amendment, except that the holders of the Replacement Notes shall not be entitled to receive any warrants in the Company which were issued in connection with the Restructured Notes. In addition, you agree that the holders of the Replacement Notes shall participate pari-pasu with any collateral granted to the holders of the Promissory Notes.

If you are in agreement with the terms of this amendment letter, please indicate so by signing below and faxing an executed copy to Ian Bothwell at
(760) 772-8588 no later than the close of business on January 16, 2004.

Very truly yours,

Penn Octane Corporation

By: __________________________________
Its: Vice President and Chief Financial Officer

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The undersigned holder of the Promissory Note and other Original Documents referred to in this amendment letter hereby acknowledges his/her/its agreement to all of the provisions of this amendment letter and intention to be so bound. The undersigned also agrees to keep the contents of this amendment letter and any documents or discussions regarding the same strictly confidential and not to use the same for any purpose pending public disclosure thereof by the Company; provided, however, that the undersigned may consult with his, her or its agents and advisors with respect to the transactions contemplated hereby and, in connection therewith, disclose the terms and contents of this amendment letter and any other documents relating to the subject matter thereof or hereof.

FirstName LastName
Company
Company1

By: __________________________________

Its: _________________________________

Date:_________________________________

Promissory Note Amount: $ Note Amt

Name and Telephone Number of Holder:





Amendment To Promissory Notes
January 13, 2004

Page 8 of 8

EXHIBIT A - DRAFT

This letter will confirm that RZB Finance LLC ("RZB") agrees to subordinate its liens and security interests in all of Penn Octane Corporation's (the "Company") assets, personal property, fixtures, intangibles and property constituting Collateral (as defined in the General Security Agreement between the Company and RZB), except for (i) cash held in the Company's accounts at RZB, (ii) inventory of every type and description, whether raw, in process or finished and all documents, documents of title and receipts covering any inventory and all products and proceeds thereof; (iii) accounts, accounts receivable, contract rights, general intangibles, payment intangibles, tax refund claims, instruments, promissory notes, chattel paper, supporting obligations, letters of credit and letter-of-credit rights and other rights to payment of money and all products and proceeds thereof; (iv) the Seadrift lease dated October 2003, as amended, modified or supplemented from time to time; (v) the Company's LPG supply agreements and all rights and remedies relating thereto and (vi) the PMI agreements, as to all of the foregoing items in clauses (i) through and including (vi), whether now owned or hereafter acquired and wherever located (all such property, except the property described in clauses (i) through and including (vi), the "Subordinated Collateral").

Accordingly, RZB consents that the Subordinated Collateral can be pledged by the Company to the Company's existing creditors (which shall be deemed to include those creditors which may substitute as note holders in connection with existing indebtedness, and the holders of any indebtedness incurred to refinance existing indebtedness) and RZB agrees that it shall not take any action which would prevent such creditors (the "Senior Creditors") from foreclosing and enforcing liens superior to RZB in such Subordinated Collateral in the event the Company is in default under the related indebtedness.

Except as expressly set forth herein, nothing contained herein shall limit or affect any of RZB's rights or remedies against the Company.

This agreement shall be governed by the laws of the State of New York without regard to principles of conflicts of law. Unless the context otherwise requires, all terms used herein which are defined in the Uniform Commercial Code of the State of New York as in effect from time to time shall have the meanings therein stated. The subordination contained herein is conditioned upon the parties submitting and consenting to the exclusive jurisdiction of the Courts of the State of New York located in New York County and of the United States District Court for the Southern District of New York in connection with any action or proceeding under, arising from or relating to this Agreement. The subordination contained herein is conditioned upon the parties waiving, to the fullest extent they may effectively do so, the defense of an inconvenient forum to the maintenance of such action or proceeding. Each of the parties agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law. The Senior Creditors and RZB hereby IRREVOCABLY WAIVE TRIAL BY JURY IN ANY ACTION OR PROCEEDING ARISING UNDER OR RELATING TO THIS AGREEMENT.

The subordination contained herein is conditioned upon the Senior Creditors not challenging or disputing (a) the validity, perfection or priority of RZB's security interest in any Collateral (other than Subordinated Collateral), or (b) any relief requested by RZB to protect or realize on its Collateral (other than Subordinated Collateral) in any bankruptcy case with respect to the Company including, without limitation, any cash collateral order or debtor-in-possession financing.

This agreement is solely for the benefit of RZB and the Senior Creditors and their successors and assigns and no other person shall have any right or benefit under or because of the existence of this Agreement.

The Senior Creditors shall permit use of any collateral subject to their senior security interest for storage, processing, transportation or delivery of RZB's collateral for a period of 60 days after notice from the Senior Creditors or their representative to RZB of the beginning of such 60-day period, all without charge, cost or expense to RZB.


CONTRIBUTION, CONVEYANCE AND ASSUMPTION AGREEMENT

This Contribution, Conveyance and Assumption Agreement (this "Agreement") is entered into as of September 16, 2004, by and among Penn Octane Corporation, a Delaware corporation ("POCC"), Rio Vista GP LLC, a Delaware limited liability company (the "GP"), Rio Vista Energy Partners L.P., a Delaware limited partnership (the "MLP"), Rio Vista Operating GP LLC, a Delaware limited liability company (the "Operating GP"), and Rio Vista Operating Partnership L.P., a Delaware limited partnership (the "Operating Partnership").

RECITALS

WHEREAS, prior to the date hereof, POCC formed the GP, as a wholly-owned direct subsidiary, and purchased for $1,000.00 all of the limited liability company interests in the GP;

WHEREAS, the GP and POCC formed the MLP, with the GP purchasing a 2% general partner interest for $20 and POCC purchasing common units representing a 98% limited partner interest for $980.00;

WHEREAS, the MLP formed the Operating GP and purchased all of the limited liability company interests in the Operating GP for $1,000.00;

WHEREAS, POCC and the Operating GP formed the Operating Partnership, with the Operating GP purchasing a 0.10% general partner interest for $1.00 and POCC purchasing a 99.9% limited partner interest for $999.00;

WHEREAS, each of the following transactions shall occur as of 4:58 P.M. Eastern Time on September 30, 2004 (the "Contribution Effective Time"):

1. POCC will contribute all of its ownership interest in the outstanding capital stock of its subsidiaries (the "Subsidiary Interests") set forth on Exhibit A (the "Subsidiaries") hereto to the Operating Partnership as a capital contribution;

2. POCC will contribute to the Operating Partnership the assets set forth in the Conveyance Agreement described in Section 1.2 below (the "LPG Assets") as an additional capital contribution; and

3. The GP will convey $1,000 to the MLP in exchange for the issuance of incentive distribution rights to the GP;

WHEREAS, each of the following transactions shall occur as of 4:59 P.M. Eastern Time on September 30, 2004 (the "Closing Day Effective Time"):

1. POCC will contribute all of its limited partner interest in the Operating Partnership to the MLP as an additional capital contribution.

NOW, THEREFORE, in consideration of their mutual undertakings and agreements hereunder, the parties to this Agreement undertake and agree as follows:

ARTICLE I

CONVERSIONS, CONTRIBUTIONS AND DISTRIBUTIONS OF VARIOUS ASSETS

SECTION 1.1 CONTRIBUTION OF THE SUBSIDIARY INTERESTS BY POCC TO THE OPERATING PARTNERSHIP. At the Contribution Effective Time, POCC hereby grants, contributes, transfers, assigns and conveys to the Operating Partnership, its successors and assigns, all right, title and interest in and to the Subsidiary Interests as a capital contribution and the Operating Partnership hereby accepts the Subsidiary Interests.


SECTION 1.2 CONTRIBUTION OF LPG ASSETS BY POCC TO THE OPERATING PARTNERSHIP. At the Contribution Effective Time, POCC hereby grants, contributes, transfers, assigns and conveys to the Operating Partnership, its successors and assigns, all right, title and interest in and to the LPG Assets as a capital contribution, and the Operating Partnership hereby accepts the LPG Assets. In order to give full effect to the foregoing grant, contribution, transfer, assignment and conveyance, POCC, as grantor, and the Operating Partnership, as grantee, shall execute a Conveyance Agreement in the form attached hereto as Exhibit B together with such other special warranty deeds, conveyances or other documents required to transfer the LPG Assets in the jurisdictions in which they are located.

SECTION 1.3 CONTRIBUTION OF OPERATING PARTNERSHIP INTEREST BY POCC TO THE MLP. At the Closing Day Effective Time, POCC hereby grants, contributes, transfers, assigns and conveys to the MLP, its successors and assigns, all right, title and interest of POCC in and to the 99.9% limited partner interest in the Operating Partnership as an additional capital contribution to the MLP and the MLP hereby accepts such limited partner interest as an additional capital contribution to the MLP.

SECTION 1.4 CONVEYANCE BY THE GP TO THE MLP. At the Contribution Effective Time, the GP hereby conveys to the MLP $1,000.00 in exchange for all of the incentive distribution rights under the First Amended and Restated Agreement of Limited Partnership of the MLP.

ARTICLE II

RECORDATION OF EVIDENCE OF OWNERSHIP OF ASSETS

SECTION 2.1. In connection with the conveyances that are referred to in Article I to this Agreement, the parties to this Agreement acknowledge that certain jurisdictions in which the assets of the applicable parties to such conveyances are located may require that documents be recorded by such parties resulting from such conveyances in order to evidence title to the assets owned by such parties. All such documents shall evidence such new ownership and are not intended to modify, and shall not modify, any of the terms, covenants and conditions herein set forth.

ARTICLE III

ASSUMPTION OF CERTAIN LIABILITIES

SECTION 3.1 ASSUMPTION OF LIABILITIES AND OBLIGATIONS BY THE OPERATING PARTNERSHIP AND THE MLP. In connection with the contributions of the LPG Assets and the Subsidiary Interests to the Operating Partnership, the Operating Partnership hereby assumes and agrees to duly and timely pay, perform and discharge all obligations and liabilities associated with the Contributed Assets, that arise from and after the Closing Day Effective Time, to the full extent that either of the Subsidiaries or POCC would have been obligated to pay, perform and discharge such obligations and liabilities in the future, were it not for the execution and delivery of this Agreement; provided, however, that said assumption and agreement to duly and timely pay, perform and discharge such obligations and liabilities shall not increase the obligation of the Operating Partnership with respect to such obligations and liabilities beyond that of POCC as to the LPG Assets, or the Subsidiaries as to the assets acquired by the Operating Partnership in such interest conveyed by any of POCC or the Subsidiaries. For purposes of this Agreement, the term "Contributed Assets" shall mean, collectively, the LPG Assets and the Subsidiary Interests.

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ARTICLE IV

TITLE MATTERS

SECTION 4.1 DISCLAIMER OF WARRANTIES; SUBROGATION.

(a) (i) NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED IN THIS AGREEMENT, THE MLP AND THE OPERATING PARTNERSHIP ACKNOWLEDGE AND AGREE THAT POCC AND THE SUBSIDIARIES HAVE NOT MADE, DO NOT MAKE, AND SPECIFICALLY NEGATE AND DISCLAIM, ANY REPRESENTATIONS, WARRANTIES, PROMISES, COVENANTS, AGREEMENTS OR GUARANTIES OF ANY KIND OR CHARACTER WHATSOEVER, WHETHER EXPRESS, IMPLIED OR STATUTORY, ORAL OR WRITTEN, PAST OR PRESENT (ALL OF WHICH ARE EXPRESSLY DISCLAIMED BY POCC AND THE SUBSIDIARIES) REGARDING (1) THE TITLE, VALUE, NATURE, QUALITY OR CONDITION OF THE CONTRIBUTED ASSETS, (2) THE INCOME TO BE DERIVED FROM THE CONTRIBUTED ASSETS, (3) THE SUITABILITY OF THE CONTRIBUTED ASSETS FOR ANY AND ALL ACTIVITIES AND USES WHICH THE MLP MAY CONDUCT THEREON,
(4) THE COMPLIANCE OF OR BY THE CONTRIBUTED ASSETS, OR THEIR OPERATIONS WITH ANY LAWS (INCLUDING WITHOUT LIMITATION ANY ZONING, ENVIRONMENTAL PROTECTION, POLLUTION OR LAND USE LAWS, RULES, REGULATIONS, ORDERS OR REQUIREMENTS), OR (5) THE HABITABILITY, MERCHANTABILITY, MARKETABILITY, PROFITABILITY OR FITNESS FOR A PARTICULAR PURPOSE OF THE CONTRIBUTED ASSETS.

(ii) THE MLP AND THE OPERATING PARTNERSHIP ACKNOWLEDGE AND AGREE THAT THEY HAVE HAD THE OPPORTUNITY TO INSPECT THE CONTRIBUTED ASSETS, AND THAT THEY ARE RELYING SOLELY ON THEIR OWN INVESTIGATION OF THE CONTRIBUTED ASSETS, AND NOT ON ANY INFORMATION PROVIDED OR TO BE PROVIDED BY POCC AND THE SUBSIDIARIES, AND POCC AND THE SUBSIDIARIES ARE NOT LIABLE OR BOUND IN ANY MANNER BY ANY VERBAL OR WRITTEN STATEMENTS, REPRESENTATIONS OR INFORMATION PERTAINING TO THE CONTRIBUTED ASSETS, FURNISHED BY ANY AGENT, EMPLOYEE, SERVANT OR THIRD PARTY.

(iii) THE MLP AND THE OPERATING PARTNERSHIP ACKNOWLEDGE THAT TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE CONTRIBUTION OF THE CONTRIBUTED ASSETS, AS PROVIDED FOR HEREIN IS MADE ON AN "AS IS", "WHERE IS" BASIS WITH ALL FAULTS AND THE CONTRIBUTED ASSETS, ARE CONTRIBUTED OR DISTRIBUTED AND CONVEYED BY POCC AND THE SUBSIDIARIES SUBJECT TO THE FOREGOING. THIS PARAGRAPH SHALL SURVIVE SUCH CONTRIBUTION OR DISTRIBUTION AND CONVEYANCE OR THE TERMINATION OF THIS AGREEMENT.

(iv) THE PROVISIONS OF THIS SECTION 4.1 HAVE BEEN NEGOTIATED BY POCC, THE SUBSIDIARIES, THE MLP AND THE OPERATING PARTNERSHIP AFTER DUE CONSIDERATION AND ARE INTENDED TO BE A COMPLETE EXCLUSION AND NEGATION OF ANY REPRESENTATIONS OR WARRANTIES OF POCC AND THE SUBSIDIARIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, WITH RESPECT TO THE CONTRIBUTED ASSETS, THAT MAY ARISE PURSUANT TO ANY LAW NOW OR HEREAFTER IN EFFECT, OR OTHERWISE.

(b) The contributions of the Contributed Assets, made under this Agreement are made with full rights of substitution and subrogation of the Operating Partnership, and all persons claiming by, through and under the Operating Partnership, to the extent assignable, in and to all covenants and warranties by the predecessors-in-title of POCC and the Subsidiaries, and with full subrogation of all rights accruing under applicable statutes of limitation and all rights of action of warranty

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against all former owners of the Contributed Assets.

(c) POCC, the Subsidiaries, the MLP, the GP, the Operating Partnership and Operating GP agree that the disclaimers contained in this Section 4.1 are "conspicuous" disclaimers. Any covenants implied by statute or law by the use of the words "grant," "convey," "bargain," "sell," "assign," "transfer," "deliver," or "set over" or any of them or any other words used in this Agreement or any exhibits hereto are hereby expressly disclaimed, waived or negated.

ARTICLE V

FURTHER ASSURANCES

SECTION 5.1 FURTHER ASSURANCES. From time to time after the date hereof, and without any further consideration, POCC, the Subsidiaries, the GP, the MLP, the Operating GP and the Operating Partnership shall execute, acknowledge and deliver all such additional deeds, assignments, conveyances, instruments, notices, releases, acquittances and other documents, and will do all such other acts and things, all in accordance with applicable law, as may be necessary or appropriate more fully and effectively to vest in the Operating Partnership and the MLP and their successors and assigns beneficial and record title to the Contributed Assets hereby contributed and assigned to the Operating Partnership or intended so to be and to more fully and effectively carry out the purposes and intent of this Agreement.

SECTION 5.2 OTHER ASSURANCES. From time to time after the date hereof, and without any further consideration, each of the parties to this Agreement shall execute, acknowledge and deliver all such additional instruments, notices and other documents, and will do all such other acts and things, all in accordance with applicable law, as may be necessary or appropriate to more fully and effectively carry out the purposes and intent of this Agreement.

ARTICLE VI

MISCELLANEOUS

SECTION 6.1 HEADINGS; REFERENCES; INTERPRETATION. All article and section headings in this Agreement are for convenience only and shall not be deemed to control or affect the meaning or construction of any of the provisions hereof. The words "hereof," "herein" and "hereunder" and words of similar import, when used in this Agreement, shall refer to this Agreement as a whole, including without limitation, all exhibits attached hereto, and not to any particular provision of this Agreement. All references herein to articles, sections, and exhibits shall, unless the context requires a different construction, be deemed to be references to the articles, sections and exhibits of this Agreement, respectively, and all such Exhibits attached hereto are hereby incorporated herein and made a part hereof for all purposes. All personal pronouns used in this Agreement, whether used in the masculine, feminine or neuter gender, shall include all other genders, and the singular shall include the plural and vice versa. The use herein of the word "including" following any general statement, term or matter shall not be construed to limit such statement, term or matter to the specific items or matters set forth immediately following such word or to similar items or matters, whether or not non-limiting language (such as "without limitation," "but not limited to," or words of similar import) is used with reference thereto, but rather shall be deemed to refer to all other items or matters that could reasonably fall within the broadest possible scope of such general statement, term or matter.

SECTION 6.2 SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon and inure to the benefit of the parties signatory hereto and their respective successors and assigns.

SECTION 6.3 NO THIRD PARTY RIGHTS. The provisions of this Agreement are intended to bind the parties signatory hereto as to each other and are not intended to and do not create rights in any other person or confer upon any other person any benefits, rights or remedies and no person is or is intended to be a third party beneficiary of any of the provisions of this Agreement.

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SECTION 6.4 COUNTERPARTS. This Agreement may be executed in any number of counterparts, all of which together shall constitute one agreement binding on the parties hereto.

SECTION 6.5 GOVERNING LAW. This Agreement shall be governed by, and construed in accordance with, the laws of the State of Texas applicable to contracts made and to be performed wholly within such state without giving effect to conflict of law principles thereof, except to the extent that it is mandatory that the law of some other jurisdiction, shall apply.

SECTION 6.6 SEVERABILITY. If any of the provisions of this Agreement are held by any court of competent jurisdiction to contravene, or to be invalid under, the laws of any political body having jurisdiction over the subject matter hereof, such contravention or invalidity shall not invalidate the entire Agreement. Instead, this Agreement shall be construed as if it did not contain the particular provision or provisions held to be invalid, and an equitable adjustment shall be made and necessary provision added so as to give effect to the intention of the parties as expressed in this Agreement at the time of execution of this Agreement.

SECTION 6.7 AMENDMENT OR MODIFICATION. This Agreement may be amended or modified from time to time only by the written agreement of all the parties hereto.

SECTION 6.8 INTEGRATION. This Agreement, together with that certain Omnibus Agreement dated of even date herewith, to be entered into by and among POCC, certain of POCC's subsidiaries, the MLP, the GP, the Operating Partnership and the Operating GP (the "Omnibus Agreement"), supersedes all previous understandings or agreements between the parties, whether oral or written, with respect to its subject matter. This document is an integrated agreement which contains the entire understanding of the parties. No understanding, representation, promise or agreement, whether oral or written, other than those contained in the Omnibus Agreement, is intended to be or shall be included in or form part of this Agreement unless it is contained in a written amendment hereto executed by the parties hereto after the date of this Agreement.

(Signatures on following page)

5

IN WITNESS WHEREOF, this Agreement has been duly executed by the parties hereto as of the date first above written.

PENN OCTANE CORPORATION

By:/s/ Richard Shore, Jr.
   ----------------------------------
     Richard  Shore,  Jr.,
     President

RIO VISTA GP LLC

By:/s/  Richard  Shore,  Jr.
   ----------------------------------
     Richard  Shore,  Jr.,
     President

RIO VISTA ENERGY PARTNERS L.P.

By: RIO VISTA GP LLC,
its General Partner

By:/s/  Richard  Shore,  Jr.
   ----------------------------------
     Richard  Shore,  Jr.,
     President

RIO VISTA OPERATING GP LLC

By:/s/  Richard  Shore,  Jr.
   ----------------------------------
     Richard  Shore,  Jr.,
     President

RIO VISTA OPERATING PARTNERSHIP L.P.

By: Rio Vista Operating GP LLC,
its General Partner

By: Rio Vista Energy Partners L.P.,
its sole member

By: Rio Vista GP LLC,
its General Partner

By:/s/ Richard Shore, Jr.
   -----------------------
     Richard  Shore,  Jr.,
     President

6

EXHIBIT A

LIST OF SUBSIDIARIES

Penn-Octane de Mexico, S. de R.L. de C.V.

Termatsal, S. de R.L. de C.V.

Penn Octane International LLC


EXHIBIT B


CONVEYANCE AGREEMENT

Recording Requested by and When Recorded Return to: Fulbright & Jaworski L.L.P., 300 Convent St., Suite 2200, San Antonio, Texas, Attn: Christian G. Herff.

CONVEYANCE AGREEMENT

This Conveyance Agreement (this "Conveyance"), effective as of 4:58 P.M. Eastern Time on September 30, 2004 (the "Effective Date"), is from PENN OCTANE CORPORATION, a Delaware corporation (herein called "Grantor"), and in favor of RIO VISTA OPERATING PARTNERSHIP L.P., whose mailing address is 820 Gessner Road, Suite 1285, Houston, TX 77024 (herein called "Grantee").

ARTICLE I

GRANTING CLAUSE

1.1 GRANTING CLAUSES. Grantor hereby contributes, conveys, assigns, transfers, delivers, and sets over unto Grantee, its successors and assigns, all right, title, interests and estate of Grantor in and to the following described property, to-wit:

ALL OF THE ASSETS SET FORTH ON SCHEDULE A ATTACHED HERETO

The property described in this Section 1.1 shall be referred to herein collectively as the "Subject Property".

TO HAVE AND TO HOLD the Subject Property, subject to the terms and conditions hereof, unto Grantee, its successors and assigns, forever.

ARTICLE II

ENCUMBRANCES AND WARRANTY DISCLAIMERS

2.1 PERMITTED ENCUMBRANCES. This Conveyance is made and accepted expressly subject to (a) all liens, charges, encumbrances, contracts, agreements, instruments, obligations, defects, restrictions, security interests, options or preferential rights to purchase, adverse claims, reservations, exceptions, easements, rights-of-way, conditions, leases, other matters affecting the Subject Property or to which it is subject; and (b) to all matters that a current on the ground survey or visual inspection would reflect.

2.2 CONTRIBUTION AGREEMENT. This Conveyance is expressly made subject to the terms and conditions of that certain Contribution, Conveyance and Assumption Agreement dated as of September 16, 2004, among Grantor, Grantee and the other parties thereto (the "Contribution Agreement"). All capitalized terms used herein shall have the meanings given to such terms in the Contribution Agreement, unless otherwise defined herein. Nothing contained in this Conveyance shall in any way affect the provisions set forth in the Contribution Agreement nor shall this Conveyance expand or contract any rights or remedies under the Contribution Agreement. This Conveyance is intended only to effect the transfer of the Subject Property to Grantee as provided for in the Contribution Agreement and shall be governed entirely in accordance with the terms and conditions of the Contribution Agreement. In the event of a conflict between the terms of this Conveyance and the terms of the Contribution Agreement, the terms of the Contribution Agreement shall prevail.

2.3 DISCLAIMER OF WARRANTIES; SUBROGATION. Except as expressly provided herein or in the Contribution Agreement, this Conveyance is made, and is accepted by Grantee, without warranty of title, express, implied or statutory, and without recourse, but with full substitution and subrogation of Grantee, and all persons claiming by, through, and under Grantee, to the extent assignable, in and to all covenants and warranties by the predecessors in title of Grantor and with full subrogation of all rights accruing under applicable statutes of limitation or prescription and all rights of action of warranty against all former owners of the Subject Property. Except as expressly provided herein or in the Contribution Agreement, any covenants implied by statute or by the

D-1

use of the words "convey", "sell", "assign", "transfer", "deliver", or "set over" or any of them or any other words used in this Conveyance, are hereby expressly disclaimed, waived and negated.

ARTICLE III

MISCELLANEOUS

3.1 FURTHER ASSURANCES. Grantor and Grantee agree to take all such further actions and to execute, acknowledge and deliver all such further documents that are necessary or useful in carrying out the purposes of this Conveyance. So long as authorized by applicable law so to do, Grantor agrees to execute, acknowledge and deliver to Grantee all such other additional instruments, notices, affidavits, deeds, conveyances, assignments and other documents and to do all such other and further acts and things as may be necessary or useful to more fully and effectively grant, assign, convey, transfer and deliver to Grantee the Subject Property conveyed hereby or intended so to be conveyed.

3.2 SUCCESSORS AND ASSIGNS; NO THIRD PARTY BENEFICIARY. This Conveyance shall be binding upon, and shall inure to the benefit of, Grantor and Grantee and their successors and assigns. The provisions of this Conveyance are not intended to and do not create rights in any other person or entity or confer upon any other person or entity any benefits, rights or remedies and no person or entity is or is intended to be a third party beneficiary of any of the provisions of this Conveyance.

3.3 GOVERNING LAW. This Conveyance and the legal relations between the parties shall be governed by, and construed in accordance with, the laws of the State of Texas, excluding any conflict of law rule which would refer any issue to the laws of another jurisdiction, except when it is mandatory that the law of the jurisdiction wherein the Subject Property is located shall apply.

3.4 HEADINGS; REFERENCES; DEFINED TERMS. All Section headings in this Conveyance are for convenience only and shall not be deemed to control or affect the meaning or construction of any of the provisions hereof. The words "hereof", "herein" and "hereunder" and words of similar import, when used in this Conveyance, shall refer to this Conveyance as a whole, including, without limitation, all Schedules and Exhibits attached hereto, and not to any particular provision of this Conveyance.

3.5 COUNTERPARTS. This Conveyance may be executed in any number of counterparts, all of which together shall constitute one agreement binding on the parties hereto.

3.6 SEVERABILITY. If any of the provisions of this Conveyance are held by any court of competent jurisdiction to contravene, or to be invalid under, the laws of any political body having jurisdiction over the subject matter hereof, such contravention or invalidity shall not invalidate the entire agreement. Instead, this Conveyance shall be construed as if it did not contain the particular provision or provisions held to be invalid and an equitable adjustment shall be made and necessary provision added so as to give effect to the intention of the parties as expressed in this Conveyance at the time of execution of this Conveyance.

D-2

IN WITNESS WHEREOF, this Conveyance has been duly executed by the parties hereto on the dates of the acknowledgments set forth below, to be effective, however, as of the Effective Date.

GRANTOR:

PENN OCTANE CORPORATION

By:

Richard Shore, Jr., President

GRANTEE:

RIO VISTA OPERATING PARTNERSHIP L.P.

By: Rio Vista Operating GP LLC,
its General Partner

By: Rio Vista Energy Partners L.P.,
its sole member

By: Rio Vista GP LLC,
its General Partner

By:

Richard Shore, Jr., President

D-3

THE STATE OF TEXAS )

)

COUNTY OF ___________ )

This instrument was acknowledged before me on the ____ day of ___________, 2004, by ______________, ______________ of ________________________, on behalf of and in [HIS/HER] capacity as __________ of ________________________.


NOTARY PUBLIC

My Commission Expires:___________________

D-4

SCHEDULE A

D-5

CONVEYANCE AGREEMENT

Recording Requested by and When Recorded Return to: Fulbright & Jaworski L.L.P., 300 Convent St., Suite 2200, San Antonio, Texas, Attn: Christian G. Herff.

CONVEYANCE AGREEMENT

This Conveyance Agreement (this "Conveyance"), effective as of 4:58 P.M. Eastern Time on September 30, 2004 (the "Effective Date"), is from PENN OCTANE CORPORATION, a Delaware corporation (herein called "Grantor"), and in favor of RIO VISTA OPERATING PARTNERSHIP L.P., whose mailing address is 820 Gessner Road, Suite 1285, Houston, TX 77024 (herein called "Grantee").

ARTICLE I

GRANTING CLAUSE

1.1 GRANTING CLAUSES. Grantor hereby contributes, conveys, assigns, transfers, delivers, and sets over unto Grantee, its successors and assigns, all right, title, interests and estate of Grantor in and to the following described property, to-wit:

ALL OF THE ASSETS SET FORTH ON SCHEDULE A ATTACHED HERETO

The property described in this Section 1.1 shall be referred to herein collectively as the "Subject Property".

TO HAVE AND TO HOLD the Subject Property, subject to the terms and conditions hereof, unto Grantee, its successors and assigns, forever.

ARTICLE II

ENCUMBRANCES AND WARRANTY DISCLAIMERS

2.1 PERMITTED ENCUMBRANCES. This Conveyance is made and accepted expressly subject to (a) all liens, charges, encumbrances, contracts, agreements, instruments, obligations, defects, restrictions, security interests, options or preferential rights to purchase, adverse claims, reservations, exceptions, easements, rights-of-way, conditions, leases, other matters affecting the Subject Property or to which it is subject; and (b) to all matters that a current on the ground survey or visual inspection would reflect.

2.2 CONTRIBUTION AGREEMENT. This Conveyance is expressly made subject to the terms and conditions of that certain Contribution, Conveyance and Assumption Agreement dated as of September 16, 2004, among Grantor, Grantee and the other parties thereto (the "Contribution Agreement"). All capitalized terms used herein shall have the meanings given to such terms in the Contribution Agreement, unless otherwise defined herein. Nothing contained in this Conveyance shall in any way affect the provisions set forth in the Contribution Agreement nor shall this Conveyance expand or contract any rights or remedies under the Contribution Agreement. This Conveyance is intended only to effect the transfer of the Subject Property to Grantee as provided for in the Contribution Agreement and shall be governed entirely in accordance with the terms and conditions of the Contribution Agreement. In the event of a conflict between the terms of this Conveyance and the terms of the Contribution Agreement, the terms of the Contribution Agreement shall prevail.

2.3 DISCLAIMER OF WARRANTIES; SUBROGATION. Except as expressly provided herein or in the Contribution Agreement, this Conveyance is made, and is accepted by Grantee, without warranty of title, express, implied or statutory, and without recourse, but with full substitution and subrogation of Grantee, and all persons claiming by, through, and under Grantee, to the extent assignable, in and to all covenants and warranties by the predecessors in title of Grantor and with full subrogation of all rights accruing under applicable statutes of limitation or prescription and all rights of action of warranty against all former owners of the Subject Property. Except as expressly provided herein or in the Contribution Agreement, any covenants implied by statute or by the

D-1

use of the words "convey", "sell", "assign", "transfer", "deliver", or "set over" or any of them or any other words used in this Conveyance, are hereby expressly disclaimed, waived and negated.

ARTICLE III

MISCELLANEOUS

3.1 FURTHER ASSURANCES. Grantor and Grantee agree to take all such further actions and to execute, acknowledge and deliver all such further documents that are necessary or useful in carrying out the purposes of this Conveyance. So long as authorized by applicable law so to do, Grantor agrees to execute, acknowledge and deliver to Grantee all such other additional instruments, notices, affidavits, deeds, conveyances, assignments and other documents and to do all such other and further acts and things as may be necessary or useful to more fully and effectively grant, assign, convey, transfer and deliver to Grantee the Subject Property conveyed hereby or intended so to be conveyed.

3.2 SUCCESSORS AND ASSIGNS; NO THIRD PARTY BENEFICIARY. This Conveyance shall be binding upon, and shall inure to the benefit of, Grantor and Grantee and their successors and assigns. The provisions of this Conveyance are not intended to and do not create rights in any other person or entity or confer upon any other person or entity any benefits, rights or remedies and no person or entity is or is intended to be a third party beneficiary of any of the provisions of this Conveyance.

3.3 GOVERNING LAW. This Conveyance and the legal relations between the parties shall be governed by, and construed in accordance with, the laws of the State of Texas, excluding any conflict of law rule which would refer any issue to the laws of another jurisdiction, except when it is mandatory that the law of the jurisdiction wherein the Subject Property is located shall apply.

3.4 HEADINGS; REFERENCES; DEFINED TERMS. All Section headings in this Conveyance are for convenience only and shall not be deemed to control or affect the meaning or construction of any of the provisions hereof. The words "hereof", "herein" and "hereunder" and words of similar import, when used in this Conveyance, shall refer to this Conveyance as a whole, including, without limitation, all Schedules and Exhibits attached hereto, and not to any particular provision of this Conveyance.

3.5 COUNTERPARTS. This Conveyance may be executed in any number of counterparts, all of which together shall constitute one agreement binding on the parties hereto.

3.6 SEVERABILITY. If any of the provisions of this Conveyance are held by any court of competent jurisdiction to contravene, or to be invalid under, the laws of any political body having jurisdiction over the subject matter hereof, such contravention or invalidity shall not invalidate the entire agreement. Instead, this Conveyance shall be construed as if it did not contain the particular provision or provisions held to be invalid and an equitable adjustment shall be made and necessary provision added so as to give effect to the intention of the parties as expressed in this Conveyance at the time of execution of this Conveyance.


IN WITNESS WHEREOF, this Conveyance has been duly executed by the parties hereto on the dates of the acknowledgments set forth below, to be effective, however, as of the Effective Date.

GRANTOR:

PENN OCTANE CORPORATION

By:/s/ Richard Shore, Jr.
   -----------------------------------
    Richard Shore, Jr.,
    President

GRANTEE:

RIO VISTA OPERATING PARTNERSHIP L.P.

By: Rio Vista Operating GP LLC,
its General Partner

By: Rio Vista Energy Partners L.P.,
its sole member

By: Rio Vista GP LLC,
its General Partner

By:/s/ Richard Shore, Jr.
   -------------------------
      Richard Shore, Jr.,
      President


THE STATE OF CALIFORNIA )

)

COUNTY OF SAN FRANCISCO )

This instrument was acknowledged before me on the 15th day of September, 2004, by Richard Shore, Jr., President of Penn Octane Corporation, on behalf of and in his capacity as President of Penn Octane Corporation.

/s/  Barbara  Booth
-------------------------------------
NOTARY  PUBLIC

My Commission Expires: Nov. 12, 2006

THE STATE OF CALIFORNIA )

)

COUNTY OF SAN FRANCISCO )

This instrument was acknowledged before me on the 15th day of September, 2004, by Richard Shore, Jr., President of Rio Vista GP LLC, on behalf of and in his capacity as President of Rio Vista GP LLC.

/s/ Barbara Booth
-------------------------------------
NOTARY  PUBLIC

My Commission Expires: Nov. 12, 2006

SCHEDULE A


DISTRIBUTION AGREEMENT

BY AND BETWEEN

PENN OCTANE CORPORATION

AND

RIO VISTA ENERGY PARTNERS L.P. AND SUBSIDIARIES

SEPTEMBER 16, 2004


DISTRIBUTION AGREEMENT

THIS DISTRIBUTION AGREEMENT (this "Agreement") is dated September 16, 2004, by and among PENN OCTANE CORPORATION., a Delaware corporation ("POC"), RIO VISTA ENERGY PARTNERS L.P., a Delaware limited partnership ("RVP"), and the Tax Subsidiaries (as defined in Article 1) of RVP.

WITNESSETH:

WHEREAS, POC is the sole limited partner of RVP and owner of common units representing a 98% limited partner interest in RVP (the "RVP Common Units"); and

WHEREAS, POC desires to distribute to its stockholders all of the RVP Common Units;

NOW, THEREFORE, in consideration of the premises and the mutual terms, covenants and conditions herein contained, and intending to be legally bound hereby, the parties hereto hereby agree as follows:

ARTICLE 1

CERTAIN DEFINITIONS

As used in this Agreement, the following terms have the following respective meanings:

1.1 "Affiliate" shall mean, with respect to POC or RVP, any Person, that directly or indirectly, is in control of, is controlled by, controls or is under common control of POC or RVP, as the case may be. For purposes of this definition, control shall include the ownership of 50% or more of the legal or beneficial interest in any Person or the power to direct or cause the direction of the management and policies of such Person, whether through the ownership of voting securities, by contract or otherwise. A Person who is an Affiliate shall only be considered an Affiliate for so long as that Person meets the definition of an Affiliate. An officer, director, general partner, managing member or trustee of a Person or Affiliate of such Person shall not be considered to be an Affiliate unless such Person is under the direct or indirect control or common control of POC or RVP, as the case may be. For purposes of clarity, POC and RVP shall not be considered to be an Affiliate of the other, nor shall any other company in which a director or officer of POC or RVP is also a director, officer or stockholder be considered an Affiliate of POC or RVP unless POC or RVP, as the case may be, itself controls such company.

1.2 "Agreement" shall have the meaning specified in the preamble.

1.3 "Business Day" shall mean any day other than Saturday, Sunday or a day on which commercial banks located in Houston, Texas are required or authorized by law to close.

1.4 "Code" shall mean the Internal Revenue Code of 1986, as amended.

1.5 "Common Unit" shall mean the common units of RVP as defined in the RVP First Amended and Restated Agreement of Limited Partnership.

1

1.6 "Distribution" shall mean the distribution by POC to its stockholders of the RVP Common Units.

1.7 "Distribution Agent" shall mean Computershare Investor Services.

1.8 "Distribution Date" shall mean the time and date as of which the Distribution is effective.

1.9 "Liability" shall mean any and all claims, demands, liabilities, responsibilities, disputes, causes of action, losses, damages, assessments, costs and expenses (including interest, awards, judgments, penalties, settlements, fines, costs of remediation, diminutions in value, costs and expenses incurred in connection with investigating and defending any claims or causes of action (including, without limitation, attorneys' fees and expenses and all fees and expenses of consultants and other professionals)) and obligations of every nature whatsoever, liquidated or unliquidated, known or unknown, matured or unmatured, or fixed or contingent.

1.10 "Nasdaq" shall mean The Nasdaq Stock Market, Inc.

1.11 "POC" shall mean Penn Octane Corporation, a Delaware corporation.

1.12 "POC Common Stock" shall mean POC's common stock, $.01 par value.

1.13 "Person" shall mean an individual, partnership, corporation, business trust, limited liability company, limited liability partnership, joint stock company, trust, unincorporated association, joint venture, governmental authority or other entity of whatever nature.

1.14 "RVP" for purposes of the assumption and indemnification provisions of this Agreement, shall include Rio Vista Energy Partners L.P. and any and all predecessors or successors thereto, whether by merger, purchase or other acquisition of substantially all of the assets or otherwise, and any and all predecessors or successors to such entities.

1.15 "RVP Assets" shall mean, collectively, all the property, assets and rights, tangible and intangible, owned or operated by the RVP Companies on, before or after the Distribution Date.

1.16 "RVP Common Units" shall have the meaning specified in the introduction to this Agreement.

1.17 "RVP Company" shall mean any Subsidiary of RVP.

1.18 "RVP First Amended and Restated Agreement of Limited Partnership" shall mean that certain limited partnership agreement of RVP dated September 16, 2004.

1.19 "RVP Properties" shall mean the properties currently or previously owned or operated by any RVP Company.

1.20 "Record Date" shall have the meaning specified in Section 2.1 hereof.


1.21 "SEC" shall mean the United States Securities and Exchange Commission.

1.22 "Subsidiary" shall mean, with respect to any Person, (i) a corporation a majority of whose Voting Stock is at the time, directly or indirectly, owned by such Person, by one or more wholly owned subsidiaries of such Person or by such Person and one or more wholly owned subsidiaries of such Person, (ii) a partnership in which such Person or a wholly owned subsidiary of such Person is, at the date of determination, a general or limited partner of such partnership, but only if such Person or its wholly owned subsidiary is entitled to receive more than fifty percent of the assets of such partnership upon its dissolution or (iii) any other Person (other than a corporation or partnership) in which such Person, a wholly owned subsidiary of such Person or such Person and one or more wholly owned subsidiaries of such Person, directly or indirectly, at the date of determination thereof, has (x) at least a majority ownership interest or
(y) the power to elect or direct the election of a majority of the directors or other governing body of such Person.

1.23 "Tax Subsidiary" shall mean, with respect to POC or RVP as the context may require, (i) any corporation or association taxable as a corporation that is connected in an unbroken chain of stock ownership satisfying the requirements of
Section 1504(a) of the Code beginning with POC or RVP as the case may be (provided that, for this purpose, after the Distribution Date, RVP shall be regarded as a corporation that is the common parent of the RVP Group); (ii) any entity not a corporation that is a "disregarded" entity for federal income tax purposes pursuant to Treasury Regulations Sections 301.7701-3 and that is owned by POC, RVP or any Tax Subsidiary of either (determined after application of clause (i) above) and (iii) any "disregarded" entity owned by POC, RVP or any Tax Subsidiary of either (determined after application of clauses (i) and (ii) above).

1.24 "Transfer Agent" shall mean Computershare Investor Services.

1.25 "Voting Stock" shall mean, with respect to any Person, securities of any class or classes of capital stock in such Person entitling the holders thereof (whether at all times or only so long as no senior class of stock has voting power by reason of any contingency) to vote in the election of the members of the board of directors or other governing body of such Person.

ARTICLE 2

MECHANICS OF DISTRIBUTION

2.1 Mechanics of RVP Distribution. The Distribution shall be effected by the distribution to each holder of record of POC Common Stock, as of the record date designated for the Distribution by or pursuant to the authorization of the Board of Directors of POC (the "Record Date"), of one Common Unit for every eight shares of POC Common Stock held by such holder. No fraction of a Common Unit shall be issued, but in lieu thereof POC shall cause the Distribution Agent to aggregate all fractional shares that would be issued but for this Section 2.1 and sell such aggregated fractional shares in the public market and the aggregate net cash proceeds of those sales shall be distributed ratably to those POC stockholders who would otherwise have received the fractional interests.

2.2 Timing of Distribution. The Board of Directors of POC shall formally or waiver of the conditions set forth in Article 3, by delivery of certificates for RVP Common Units to the Transfer Agent for delivery of Common Units to the holders entitled thereto. The Distribution shall be deemed to be effective upon notification by POC to the Transfer Agent that the Distribution has been declared and that the Transfer Agent is authorized to proceed with the distribution of the Common Units.

ARTICLE 3

CONDITIONS TO OBLIGATIONS OF POC

The obligations of POC to consummate the Distribution hereunder shall be subject to the fulfillment of each of the following conditions:

(a) The Board of Directors of POC and the Independent Committee of the Board of Directors of POC shall be satisfied that, after giving effect to the Distribution and the transactions contemplated under the Contribution, Conveyance and Assumption Agreement dated September 16, 2004 (the "Contribution Agreement") by and among POC, RVP, the GP (as defined therein), the Operating GP (as defined therein) and the Operating Partnership (as defined therein), (i) POC will not be insolvent and will not have unreasonably small capital with which to engage in its businesses and (ii) the POC surplus (as such term is defined by Delaware General Corporation Law) will be sufficient to permit, without violation of Delaware law, the Distribution.

(b) POC and RVP (or its Subsidiary) shall have executed the Purchase Contract for the sale of liquified petroleum gas by POC to RVP (or its Subsidiary).

(c) POC and RVP shall have executed the Omnibus Agreement, which is to govern the business relationship between POC and RVP following the Distribution.

(d) The transactions contemplated under the Contribution Agreement shall have been effected.

(e) The Common Units shall have been approved for trading on the National Market System of the Nasdaq Stock Market or on such other public market acceptable to the Board of Directors of POC, and the Nasdaq Stock Market or such other public market shall not have (i) withdrawn its certification filed with the SEC that the Common Units have been approved for listing, (ii) suspended trading in either the Common Units or the POC Common Stock or (iii) filed with the SEC a Form 25 to strike either the Common Units or the POC Common Stock from listing and registration thereof.

(f) RVP's Registration Statement on Form 10 shall have become effective pursuant to Section 12 of the Securities Exchange Act of 1934, as amended, and the SEC shall not have commenced any action to prohibit or restrict the Distribution in any way.


(g) All material governmental and third party approvals and consents necessary to consummate the transactions contemplated under this Agreement and the Contribution Agreement shall have been obtained.

(h) No order, injunction or decree issued by any court or agency of competent jurisdiction or other legal restraint or prohibition preventing the Distribution or any of the other transactions contemplated by this Agreement and the other agreements relating to the Distribution may be in effect.

(i) The Board of Directors of POC and the Independent Committee of the Board of Directors of POC shall have received a copy of an independent appraisal of the assets to be transferred pursuant to the Contribution Agreement, and each of the Board of Directors of POC and the Independent Committee of the Board of Directors of POC have determined in their sole discretion that, based on such independent appraisal, the estimated tax liabilities to be incurred by POC as a result of the Distribution are acceptable.

(j) The Board of Directors of POC and the Independent Committee of the Board of Directors of POC shall not have determined, in their sole discretion, to abandon, defer or modify the Distribution or the terms thereof.

ARTICLE 4

MISCELLANEOUS

4.1 RVP Covenants. To assure the performance of the obligations of RVP under this Agreement, RVP hereby covenants and agrees that it will not, and will cause its respective Subsidiaries not to, merge, convert into another entity, engage in a share exchange for a majority of its units, liquidate or transfer, assign or otherwise convey or allocate, directly or indirectly, in one or more transactions, whether or not related, a majority of its assets (determined in good faith by a board resolution prior to the transaction on a fair value and consolidated basis) to any Person unless the acquiring Person (i) expressly assumes the obligations of it hereunder, (ii) executes and delivers to POC an agreement, in form and substance satisfactory to POC, agreeing to be bound by each and every provision of this Agreement as if it were RVP and (iii) has a net worth on a pro forma basis after giving effect to the acquisition or business combination equal to or greater than that of RVP (on a consolidated basis) and RVP's compliance with the provisions Article 3 of this Agreement. Any such assumption of liability by the acquiring Person shall not release RVP from its obligations under this Agreement.

4.2 Governing Law. All questions arising out of this Agreement and the rights and obligations created herein, or its validity, existence, interpretation, performance or breach, shall be governed by and construed in accordance with the internals laws of the State of Texas, without regard to or the application of the rules of conflicts of laws set forth in such laws.

4.3 Notices. All notices and other communications to be given or made hereunder shall be in writing and shall be (a) personally delivered with signed receipt obtained acknowledging delivery; (b) transmitted by postage prepaid registered mail, return receipt requested (air mail if international); or (c) transmitted by facsimile; to a party at the address set

out below (or at such other address as it may have provided notification for the purposes hereof to the other party hereto in accordance with this Section).

If to RVP or to any of the  Rio Vista GP LLC
Tax Subsidiaries of RVP:    820 Gessner Road, Suite 1285
                            Houston, Texas  77024
                            Fax number:  (713) _________
                            Attention:   President

                            With a copy to:

                            Fulbright & Jaworski L.L.P.
                            300 Convent St., Suite 2200
                            San Antonio, Texas 78205
                            Fax number:  (210) 270-7205
                            Attention:  Phillip M. Renfro

If to POC:                  Penn Octane Corporation
                            77-530 Enfield Lane, Building D
                            Palm Desert, CA 92211
                            Fax number:  (760) 772-8588
                            Attention:   President

                            With a copy to:

                            Fulbright & Jaworski L.L.P.
                            300 Convent St., Suite 2200
                            San Antonio, Texas 78205
                            Fax number:  (210) 270-7205
                            Attention:  Phillip M. Renfro

4.4 Expenses. Except as otherwise set forth herein or in any agreement executed in connection herewith all costs and expenses related to the Distribution and the transactions contemplated hereby shall be borne by POC.

4.5 Entire Agreement. This Agreement, including the Schedules, Annexes and other writings referred to herein or delivered pursuant hereto, the Omnibus Agreement dated of even date herewith between POC and RVP and the Contribution Agreement constitute the entire agreement between POC, RVP and the Tax Subsidiaries of RVP with respect to the subject matter hereof and supersede all other agreements, representations, warranties, statements, promises and understandings, whether oral or written, with respect to the subject matter hereof. This Agreement may not be amended, altered or modified except by a writing signed by duly authorized officers of POC, RVP and the Tax Subsidiaries of RVP.

4.6 Waiver. No consent or waiver, express or implied, by a party hereto to or of any breach or default by the other party hereto in the performance by such other party of its

obligations hereunder will be deemed or construed to be a consent or waiver to or of any other breach or default in the performance by such other party of the same or any other obligations of such other party hereunder. Failure on the part of a party to complain of any act or failure to act of the other party or to declare the other party in default, irrespective of how long such failure continues, will not constitute a waiver by such party of its rights hereunder. The giving of consent by a party in any one instance will not limit or waive the necessity to obtain such party's consent in any future instance.

4.7 Binding Effect; Assignment; No Third Party Benefit.

(a) This Agreement will be binding upon and inure to the benefit of and be enforceable by the parties hereto and their respective successors and permitted assigns. None of the parties to this Agreement may assign its rights under this Agreement without the prior written consent of all of the other parties; provided, however, POC may assign any of its rights and obligations under this Agreement to any Subsidiary of POC, without the consent of any other party to this Agreement.

(b) Nothing in this Agreement, express or implied, is intended to or shall confer upon any person other than RVP, POC, the RVP Indemnified Parties and the Tax Subsidiaries of RVP any rights, benefits or remedies of any nature whatsoever under or by reason of this Agreement.

4.8 Counterparts. This Agreement may be executed simultaneously in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same agreement.

4.9 References. All references in this Agreement to Articles, Sections and other subdivisions refer to the Articles, Sections and other subdivisions of this Agreement unless expressly provided otherwise. The words "this Agreement", "herein", "hereof", "hereby", "hereunder" and words of similar import refer to this Agreement as a whole and not to any particular subdivision unless expressly so limited.

4.10 Terminology. All personal pronouns used in this Agreement, whether used in the masculine, feminine or neuter gender, will include all other genders; and the singular will include the plural and vice versa. The headings of the Articles and Sections of this Agreement are included for convenience only and will not be deemed to constitute part of this Agreement or to affect the construction hereof or thereof.

4.11 Severability. Any provision of this Agreement that is determined by arbitration as provided herein or a court of competent jurisdiction to be invalid, illegal or unenforceable shall be ineffective to the extent of such invalidity, illegality or unenforceability, without affecting in any way the remaining provisions hereof in such jurisdiction or rendering that or any other provision of this Agreement invalid, illegal or unenforceable, so long as the material purposes of this Agreement can be determined and effectuated. Should any provision of this Agreement be so declared invalid, illegal or unenforceable, the parties shall agree on a valid provision to substitute for it.

4.12 Further Assurances. Each party hereto agrees to do all acts and things and to make, execute and deliver such written instruments, as will from time to time be reasonably required to carry out the terms and provisions of this Agreement.

4.13 Amendments. Any term of this Agreement may be amended and the observance of any term of this Agreement may be waived, only by a written instrument executed by POC, RVP and the Tax Subsidiaries of RVP.

[SIGNATURES ON FOLLOWING PAGE]


IN WITNESS WHEREOF, the parties hereto have executed this Distribution Agreement as of the date first set forth in the introduction to this Agreement.

PENN OCTANE CORPORATION

By: /s/ Richard Shore, Jr.
   -----------------------------------
        Richard  Shore,  Jr.,
        President

RIO VISTA ENERGY PARTNERS L.P.

By: RIO VISTA GP LLC,
its General Partner

By:/s/ Richard Shore, Jr.
   -------------------------------
       Richard Shore, Jr.,
       President


OMNIBUS AGREEMENT

BETWEEN

PENN OCTANE CORPORATION,

RIO VISTA GP LLC,

RIO VISTA ENERGY PARTNERS L.P.

AND

RIO VISTA OPERATING PARTNERSHIP L.P.


OMNIBUS AGREEMENT

THIS OMNIBUS AGREEMENT is entered into as of September 16, 2004 by and among Penn Octane Corporation, a Delaware corporation ("POCC"), Rio Vista GP LLC, a Delaware limited liability company (the "General Partner"), Rio Vista Energy Partners L.P., a Delaware limited partnership (the "Partnership"), and Rio Vista Operating Partnership L.P. (the "Operating Partnership"). The above-named entities are sometimes referred to in this Agreement each as a "Party" and collectively as the "Parties."

RECITALS:

WHEREAS, POCC and its Affiliates (as defined herein) formed the Partnership, the General Partner and the Operating Partnership for the purpose of conducting of the Business (as defined below);

WHEREAS, certain assets and services used by POCC or its Affiliates in the conduct of the Business prior to the formation of the Partnership were not transferred to the Partnership;

WHEREAS, the Parties desire to ensure the continued effective operation of the Business, and the Parties recognize that the continued effective operation of the Business requires that POCC provide certain management and employee services to the Business as set forth in this Agreement; and

WHEREAS, the Parties desire to evidence other agreements and relationships, as more fully set out in this Agreement, with respect to the transfer of the Business to the Partnership and the Operating Partnership as well as the operation of the Business by the Partnership and the Operating Partnership.

NOW THEREFORE, in consideration of the premises and the covenants, conditions, and agreements contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties hereto hereby agree as follows:

ARTICLE I

DEFINITIONS

DEFINITIONS. (a) As used in this Agreement, the following terms shall have the respective meanings set forth below:

"Affiliate" means, with respect to any Person, any other Person that directly or indirectly through one or more intermediaries controls, is controlled by or is under common control with, the Person in question. As used herein, the term "control" means the possession, direct or indirect, of the power to direct or cause the direction of the management and policies of a Person, whether through ownership of voting securities, by contract or otherwise.

2

"Agreement" means this Omnibus Agreement, as it may be amended, modified, or supplemented from time to time in accordance with Section 4.7 hereof.

"Assets" means the "Contributed Assets" as such term is defined in the Contribution Agreement.

"Business" means (i) providing transportation, terminalling and distribution services for hydrocarbon products and by-products, and (ii) marketing and selling hydrocarbon products and by-products.

"Closing Date" means the date of the Distribution.

"Conflicts Committee" is defined in the Partnership Agreement.

"control" means the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of a Person, whether through ownership of voting securities, by contract or otherwise.

"Contribution Agreement" means the Contribution, Conveyance and Assumption Agreement, dated September 16, 2004, by and among various POCC Entities, the Partnership, the Operating Partnership, the General Partner and Rio Vista Operating GP LLC, a Delaware limited liability company.

"Covered Environmental Losses" is defined in Section 2.1(a).

"Distribution" means the distribution by POCC of all the outstanding common units of the Partnership representing limited partner interests to the stockholders of POCC.

"Environmental Laws" means all federal, state, and local laws, statutes, rules, regulations, orders, and ordinances, now or hereafter in effect, relating to protection of human health and the environment including, without limitation, the federal Comprehensive Environmental Response, Compensation, and Liability Act, the Superfund Amendments Reauthorization Act, the Resource Conservation and Recovery Act, the Clean Air Act, the Federal Water Pollution Control Act, the Toxic Substances Control Act, the Oil Pollution Act, the Safe Drinking Water Act, the Hazardous Materials Transportation Act, and other environmental conservation and protection laws, each as amended from time to time.

"General Partner" is defined in the introduction to this Agreement.

"Hazardous Substance" means any substance that is designated, defined, or classified as a hazardous waste, hazardous material, pollutant, contaminant, or toxic or hazardous substance, or that is otherwise regulated under any Environmental Law, including, without limitation, any hazardous substance as defined under the Comprehensive Environmental Response, Compensation, and Liability Act.

3

"Indemnified Party" means the Partnership Entities or the POCC Entities, as the case may be, in their capacity as the parties entitled to indemnification in accordance with Article II.

"Indemnifying Party" means either the Partnership Entities or the POCC Entities, as the case may be, in its capacity as the parties from whom indemnification may be sought in accordance with Article II.

"Losses" means any losses, damages, liabilities, claims, demands, causes of action, judgments, settlements, fines, penalties, costs, and expenses (including, without limitation, court costs and reasonable attorney's and expert's fees) of any and every kind or character.

"POCC" is defined in the introduction to this Agreement.

"POCC Entities" means POCC and each of its Subsidiaries (other than the General Partner, the Partnership and any Subsidiary of the Partnership).

"Partnership" is defined in the introduction to this Agreement.

"Partnership Agreement" means the First Amended and Restated Agreement of Limited Partnership of Rio Vista Energy Partners L.P. No amendment or modification to the Partnership Agreement subsequent to the Closing Date shall be given effect for the purposes of this Agreement unless consented to by each of the Parties to this Agreement.

"Partnership Entities" means the Partnership, the General Partner and each Subsidiary of the Partnership.

"Party" and "Parties" is defined in the introduction to this Agreement.

"Pass-Through Environmental Losses" is defined in Section 2.1(b).

"Person" means an individual or a corporation, limited liability company, partnership, joint venture, trust, unincorporated organization, association, government agency or political subdivision thereof or other entity.

"Retained Assets" means, collectively, any assets and investments owned by any of the POCC Group that were not conveyed, contributed or otherwise transferred to any of the Partnership Entities prior to or on the Closing Date.

"Services" is defined in Section 3.1.

"Subsidiary" means, with respect to any Person, (a) a corporation of which more than 50% of the voting power is owned, directly or indirectly, at the date of determination, by such Person, by one or more Subsidiaries of such Person or a combination thereof, (b) a partnership (whether general or limited) in which such Person or a Subsidiary of such Person is, at the date of determination, a general or limited partner of such partnership, but only if more than 50% of the partnership interests of such partnership (considering all of the partnership interests of the

4

partnership as a single class) is owned, directly or indirectly, at the date of determination, by such Person, by one or more Subsidiaries of such Person, or a combination thereof, or (c) any other Person (other than a corporation or a partnership) in which such Person, one or more Subsidiaries of such Person, or a combination thereof, directly or indirectly, at the date of determination, has
(i) at least a majority ownership interest or (ii) the power to elect or direct the election of a majority of the directors or other governing body of such Person.

ARTICLE II

INDEMNIFICATION

2.1 ENVIRONMENTAL INDEMNIFICATION.

(a) Subject to the limitations contained in this Section 2.1(a), POCC shall indemnify, defend and hold harmless each of the Partnership Entities from and against environmental and toxic tort Losses suffered, incurred or paid by any of the Partnership Entities by reason of or arising out of:

(i) any violation or correction of violation of Environmental Laws associated with the Assets or the Retained Assets, or

(ii) any event or condition associated with the ownership or operation of the Assets or the Retained Assets (including, without limitation, the presence of Hazardous Substances on, under, about or migrating to or from the Assets or the Retained Assets or the disposal or release of Hazardous Substances generated by operation of the Assets or the Retained Assets at non-Asset locations) including, without limitation, (A) the cost and expense of any investigation, assessment, evaluation, monitoring, containment, cleanup, repair, restoration, remediation, or other corrective action required or necessary under Environmental Laws, (B) the cost or expense of the preparation and implementation of any closure, remedial, corrective action, or other plans required or necessary under Environmental Laws, and (C) the cost and expense for any environmental or toxic tort pre-trial, trial, or appellate legal or litigation support work,

but only to the extent that such violation complained of under Section 2.1(a)(i) or such events or conditions included under Section 2.1(a)(ii) occurred before the Closing Date (collectively, "Covered Environmental Losses").

(b) POCC shall indemnify, defend and hold harmless any of the Partnership Entities from and against any Losses suffered or incurred by any of the Partnership Entities to the extent that POCC is entitled to and receives indemnification, is defended or held harmless against any such Losses from any third-party pursuant to any agreement between any third-party and POCC (collectively, "Pass-Through Environmental Losses"). In furtherance of such agreement, POCC agrees to use its best commercially reasonable efforts to pursue, for the benefit of the Partnership Entities, any such indemnification with respect to which it might be entitled if

5

requested by the Partnership; provided that, the Partnership shall reimburse POCC for all costs and expenses incurred in connection with pursuing such indemnity on behalf of the Partnership.

(c) The Partnership shall indemnify, defend and hold harmless POCC from and against Losses suffered or incurred by any of the POCC Entities by reason of or arising out of:

(i) any violation or correction of violation of Environmental Laws associated with the Assets, or

(ii) any event or condition associated with ownership or operation of the Assets (including, but not limited to, the presence of Hazardous Substances on, under, about or migrating to or from the Assets or the disposal or release of Hazardous Substances generated by operation of the Assets at non-Asset locations) including, without limitation, (A) the cost and expense of any investigation, assessment, evaluation, monitoring, containment, cleanup, repair, restoration, remediation, or other corrective action required or necessary under Environmental Laws, (B) the cost or expense of the preparation and implementation of any closure, remedial, corrective action, or other plans required or necessary under Environmental Laws, and (C) the cost and expense for any environmental or toxic tort pre-trial, trial, or appellate legal or litigation support work,

but only to the extent such violation complained of under Section 2.1(c)(i) or such events or conditions included under Section 2.1(c)(ii) occurred after the Closing Date.

2.2 ADDITIONAL INDEMNIFICATION

(a) In addition to and not in limitation of the indemnification provided under Sections 2.1(a) and 2.1(b), POCC shall indemnify, defend, and hold harmless the Partnership Entities from and against any Losses suffered or incurred by the Partnership Entities by reason of or arising out of

(i) any events and conditions associated with the ownership or operation of the Retained Assets, whether occurring before or after the Closing Date,

(ii) the failure of the Partnership Entities to be the owner of such valid leasehold interests or fee ownership interests in and to the Assets as are necessary to enable the Partnership Entities to continue to own and operate the Assets and the Business in the same manner that the Assets and the Business were owned and operated by the POCC Entities during the one-year period immediately prior to the Closing Date to the extent that POCC is notified of any of the foregoing within three years after the Closing Date,

(iii) the failure of the Partnership Entities to have any consent or permit necessary to allow the Partnership Entities to own or operate the Assets and the Business in the same manner that the Assets and the Business were owned and operated by the POCC Entities

6

during the one-year period immediately prior to the Closing Date to the extent that POCC is notified of any of the foregoing within three years after the Closing Date,

(iv) all legal actions against POCC, including without limitation, those set forth on Schedule 2.2 hereto, and

(v) all federal, state and local income tax liabilities attributable to the operation of the Assets prior to the Closing Date.

(b) In addition to and not in limitation of the indemnification provided under Sections 2.1(c), or under the Partnership Agreement, the Partnership shall indemnify, defend, and hold harmless the POCC Entities from and against any Losses suffered or incurred by any of the POCC Entities by reason of or arising out of events and conditions associated with:

(i) the operation of the Assets and the Business,

(ii) the performance of the Services by POCC and/or its employees pursuant to this Agreement (provided that POCC is not in breach of this Agreement), in each case occurring on or after the Closing Date (other than Covered Environmental Losses which are provided for under Section 2.1), unless in any such case such indemnification would not be permitted under Section 7.7 of the Partnership Agreement, and

(c) In addition to and not in limitation of the indemnification provided under Sections 2.1(c) and 2.2(b), or under the Partnership Agreement, the Partnership shall indemnify, for a period of three years from the fiscal year end that includes the Closing Date, the POCC Entities for federal income tax liabilities, including penalties and interest, resulting from the Distribution and restructuring transactions connected with it to the extent such federal income tax liabilities exceed $2.5 million in the aggregate.

2.3 INDEMNIFICATION PROCEDURES.

(a) The Indemnified Party agrees that within a reasonable period of time after it becomes aware of facts giving rise to a claim for indemnification under this Article II, it will provide notice thereof in writing to the Indemnifying Party, specifying the nature of and specific basis for such claim.

(b) The Indemnifying Party shall have the right to control all aspects of the defense of (and any counterclaims with respect to) any claims brought against the Indemnified Party that are covered by the indemnification under this Article II, including, without limitation, the selection of counsel, determination of whether to appeal any decision of any court and the settling of any such matter or any issues relating thereto; provided however, that no such settlement shall be entered into without the consent of the Indemnified Party unless it includes a full release of the Indemnified Party from such matter or issues, as the case may be.

7

(c) The Indemnified Party agrees to cooperate fully with the Indemnifying Party, with respect to all aspects of the defense of any claims covered by the indemnification under this Article II, including, without limitation, the prompt furnishing to the Indemnifying Party of any correspondence or other notice relating thereto that the Indemnified Party may receive, permitting the name of the Indemnified Party to be utilized in connection with such defense, the making available to the Indemnifying Party of any files, records or other information of the Indemnified Party that the Indemnifying Party considers relevant to such defense and the making available to the Indemnifying Party of any employees of the Indemnified Party; provided however, that in connection therewith the Indemnifying Party agrees to use reasonable efforts to minimize the impact thereof on the operations of the Indemnified Party. In no event shall the obligation of the Indemnified Party to cooperate with the Indemnifying Party as set forth in the immediately preceding sentence be construed as imposing upon the Indemnified Party an obligation to hire and pay for counsel in connection with the defense of any claims covered by the indemnification set forth in this Article II; provided however, that the Indemnified Party may, at its own option, cost and expense, hire and pay for counsel in connection with any such defense. The Indemnifying Party agrees to keep any such counsel hired by the Indemnified Party reasonably informed as to the status of any such defense, but the Indemnifying Party shall have the right to retain sole control over such defense.

(d) In determining the amount of any Losses for which the Indemnified Party is entitled to indemnification under this Agreement, the gross amount of the indemnification will be reduced by (i) any insurance proceeds realized or to be realized by the Indemnified Party, and such correlative insurance benefit shall be net of any incremental insurance premium that becomes due and payable by the Indemnified Party as a result of such claim and (ii) all amounts recovered or recoverable by the Indemnified Party under contractual indemnities from third parties.

ARTICLE III

SERVICES AND RELATED PARTY TRANSACTIONS

3.1 SERVICES. During the term of this Agreement, POCC agrees to provide (either directly or through its Subsidiaries) on behalf of the General Partner in accordance with Article VII of the Partnership Agreement, the employees or independent contractors, corporate staff, support services and administrative services necessary to operate the Business (the "Services"). POCC shall perform the Services in a manner that is substantially identical in nature and quality to the services performed by POCC for the Business during the one-year period immediately prior to the Closing Date. The General Partner and the Partnership agree that POCC shall be reimbursed for all costs and expenses incurred in connection with the performance of the Services as if it were the General Partner in accordance with Section 7.4(b) and 7.6(c) of the Partnership Agreement.

3.2 DESIGNATION OF AGENTS. In connection with the provision of the Services by the employees of POCC, the General Partner, on behalf of the Partnership, hereby appoints and empowers POCC and each current and future employee of POCC who is fulfilling a job

8

function for the Partnership in connection with the conduct by the Partnership of its business in the ordinary course, as agent of the Partnership with full power and authority to execute and deliver on behalf of the Partnership, any documents, contracts, governmental filings or other instruments commensurate with, but limited to, such job function. The power and authority granted pursuant to this Section 3.2 to a person described in the preceding sentence will be valid only for so long as such person is employed by POCC.

3.3 RIGHT TO OPERATE. POCC shall have the right, but not the obligation, to act as operator of the Partnership's facilities to the same extent it acted as operator of such facilities prior to the effective date of this Agreement for so long as POCC has responsibilities associated with such facilities.

3.4 RELATED PARTY TRANSACTIONS. Each of POCC, the General Partner, the Partnership and the Operating Partnership agree that the execution or material amendment of any "significant agreement" (as such term is defined below) must be approved by the Conflicts Committee. The term "significant agreement" means any agreement between the General Partner, the Partnership or the Operating Partnership, on the one hand, and any POCC Entity, on the other hand, that requires aggregate annual payments to or from any POCC Entity or POCC Entities in excess of $100,000.

3.5 BREACH BY PENN OCTANE. In the event POCC fails to perform the Services as provided in Section 3.1 and does not cure such failure within ten (10) days of receiving written notice of same from the General Partner, the Partnership, in addition to any other remedies at law or in equity, may terminate this Agreement and engage a third party for the provision of the Services. POCC shall cooperate in good faith with the Partnership and the General Partner in transitioning the Services to any such third party.

ARTICLE IV

MISCELLANEOUS

4.1 INSURANCE MATTERS. POCC hereby agrees to cause each of the Partnership Entities to be named as additional insureds in POCC's current insurance program, which is described on Schedule 4.1 attached hereto. Each of the Partnership Entities shall pay for its allocated cost of that insurance coverage in an amount equal to POCC's cost of insuring the assets and operations of Partnership Entity and generally in accordance with the allocations and methodology described in Schedule 4.1.

4.2 CHOICE OF LAW; SUBMISSION TO JURISDICTION. This Agreement shall be subject to and governed by the laws of the State of Texas, excluding any conflicts-of-law rule or principle that might refer the construction or interpretation of this Agreement to the laws of another state. Each Party hereby submits to the jurisdiction of the state and federal courts in Harris County, Texas.

9

4.3 NOTICE. All notices or requests or consents provided for by, or permitted to be given pursuant to, this Agreement must be in writing and must be given by depositing same in the United States mail, addressed to the Person to be notified, postpaid, and registered or certified with return receipt requested or by delivering such notice in person or by telecopier or telegram to such Person. Notice given by personal delivery or mail shall be effective upon actual receipt. Notice given by telegram or telecopier shall be effective upon actual receipt if received during the recipient's normal business hours, or at the beginning of the recipient's next business day after receipt if not received during the recipient's normal business hours. All notices to be sent to a Party pursuant to this Agreement shall be sent to or made at the address set forth below such Party's signature to this Agreement, or at such other address as such Party may stipulate to the other parties in the manner provided in this Section 4.3.

4.4 ENTIRE AGREEMENT. This Agreement constitutes the entire agreement of the Parties relating to the matters contained herein, superseding all prior contracts or agreements, whether oral or written, relating to the matters contained herein.

4.5 TERMINATION. Unless earlier terminated as provided in this Section 4.5, the term of this Agreement shall be five (5) years from the date hereof and shall be automatically renewed for subsequent five (5) year terms, unless and until either party provides written notice to the other party at least sixty
(60) days prior to the expiration of the initial five (5) year term or any renewal term that such party does not wish to renew this Agreement on the expiration of the then current term. This Agreement, other than the provisions of Article II, shall terminate on the earlier to occur of (i) ninety (90) days after either party notifies the other party in writing that the Partnership is no longer an Affiliate of POCC and (ii) this Agreement is terminated by the Partnership under Section 3.5. Termination of this Agreement shall not terminate any Indemnifying Party's continuing obligation of indemnification pursuant to Article II of this Agreement which obligations shall survive as provided in Article II.

4.6 EFFECT OF WAIVER OR CONSENT. No waiver or consent, express or implied, by any Party to or of any breach or default by any Person in the performance by such Person of its obligations hereunder shall be deemed or construed to be a consent or waiver to or of any other breach or default in the performance by such Person of the same or any other obligations of such Person hereunder. Failure on the part of a Party to complain of any act of any Person or to declare any Person in default, irrespective of how long such failure continues, shall not constitute a waiver by such Party of its rights hereunder until the applicable statute of limitations period has run.

4.7 AMENDMENT OR MODIFICATION. This Agreement may be amended or modified from time to time only by the written agreement of all the Parties hereto; provided however, that the Partnership may not, without the prior approval of the Conflicts Committee, agree to any amendment or modification of this Agreement. Each such instrument shall be reduced to writing and shall be designated on its face an "Amendment" or an "Addendum" to this Agreement.

10

4.8 ASSIGNMENT. No Party shall have the right to assign its rights or obligations under this Agreement without the consent of the other Parties hereto.

4.9 COUNTERPARTS. This Agreement may be executed in any number of counterparts with the same effect as if all signatory parties had signed the same document. All counterparts shall be construed together and shall constitute one and the same instrument.

4.10 SEVERABILITY. If any provision of this Agreement or the application thereof to any Person or circumstance shall be held invalid or unenforceable to any extent, the remainder of this Agreement and the application of such provision to other Persons or circumstances shall not be affected thereby and shall be enforced to the greatest extent permitted by law.

4.11 FURTHER ASSURANCES. In connection with this Agreement and all transactions contemplated by this Agreement, each signatory party hereto agrees to execute and deliver such additional documents and instruments and to perform such additional acts as may be necessary or appropriate to effectuate, carry out and perform all of the terms, provisions and conditions of this Agreement and all such transactions.

4.12 LAWS AND REGULATIONS. Notwithstanding any provision of this Agreement to the contrary, no Party to this Agreement shall be required to take any act, or fail to take any act, under this Agreement if the effect thereof would be to cause such Party to be in violation of any applicable law, statute, rule or regulation.

4.13 NEGOTIATION OF RIGHTS OF LIMITED PARTNERS, ASSIGNEES, AND THIRD PARTIES. The provisions of this Agreement are enforceable solely by the Parties to this Agreement, and no limited partner, member, assignee or other Person of the Partnership or General Partner shall have the right, separate and apart from the Partnership or the General Partner, to enforce any provision of this Agreement or to compel any Party to this Agreement to comply with the terms of this Agreement.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK.]

11

IN WITNESS WHEREOF, the Parties hereto have executed this Omnibus Agreement on, and effective as of, the date first written above.

RIO VISTA ENERGY PARTNERS, L.P.

By: RIO VISTA GP LLC,
On behalf of itself and on behalf of
Partnership as its General Partner

By:/s/ Richard Shore, Jr.
   -------------------------
Name: Richard Shore, Jr.
Title: President

RIO VISTA OPERATING PARTNERSHIP L.P.

By: RIO VISTA OPERATING GP LLC

By: RIO VISTA ENERGY PARTNERS
L.P., its sole member

By: RIO VISTA GP LLC

By:/s/ Richard Shore, Jr.
   -------------------------
       Richard Shore, Jr.,
       President

PENN OCTANE CORPORATION

By: /s/ Jerome B. Richter
    ------------------------
Name: Jerome B. Richter
Title: Chief Executive Officer

12

SCHEDULE 2.2

PENDING LEGAL ACTIONS AGAINST PENN OCTANE CORPORATION

NONE

13

SCHEDULE 4

INSURANCE

14

AMENDMENT NO. 1

TO

OMNIBUS AGREEMENT

BETWEEN

PENN OCTANE CORPORATION,

RIO VISTA GP LLC,

RIO VISTA ENERGY PARTNERS L.P.

AND

RIO VISTA OPERATING PARTNERSHIP L.P.


AMENDMENT NO. 1
TO OMNIBUS AGREEMENT

THIS AMENDMENT NO. 1 TO OMNIBUS AGREEMENT (this "Agreement") is entered into effective as of September 16, 2004 by and among Penn Octane Corporation, a Delaware corporation ("POCC"), Rio Vista GP LLC, a Delaware limited liability

company (the "General Partner"), Rio Vista Energy Partners L.P., a Delaware limited partnership (the "Partnership"), and Rio Vista Operating Partnership L.P. (the "Operating Partnership"). The above-named entities are sometimes referred to in this Agreement each as a "Party" and collectively as the "Parties."

RECITALS:

WHEREAS, each of the Parties is a party to that certain Omnibus Agreement dated as of September 16, 2004 (the "Original Agreement");

WHEREAS, it was and is the intent of the Parties under Section 2.2(b)(i) of the Original Agreement that the Partnership indemnify, defend and hold harmless the POCC Entities from and against any Losses arising out of events or conditions associated with the operation of the Assets rather than the Assets and the Business as set forth in the Original Agreement;

WHEREAS, it was and is the intent of the Parties that the definition of "Business" in the Original Agreement means the business conducted through the use of the Assets;

WHEREAS, the Parties desire to amend the Original Agreement to reflect their intent with respect to such indemnity and definition of Business; and

WHEREAS, in accordance with Section 4.7 of the Original Agreement, the amendment to the Original Agreement effected by this Agreement has been approved by the Conflicts Committee.

NOW THEREFORE, in consideration of the premises and the covenants, conditions, and agreements contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties hereto hereby agree as follows:

1. Capitalized terms used in this Agreement shall have the same meanings as set forth in the Original Agreement unless otherwise defined herein.

2. The definition of "Business" in Article I of the Original Agreement is hereby replaced, amended, restated and superseded in its entirety with the following:

"Business" means the business conducted through the use of the Assets, including (i) providing transportation, terminalling and distribution services for hydrocarbon products and by-products, and (ii) marketing and selling hydrocarbon products and by-products.

3. Section 2.2(b)(i) of the Original Agreement is hereby replaced, amended, estated and superseded in its entirety with the following:

"(i) the operation of the Assets,"


4. Any and all of the terms and conditions of the Original Agreement are hereby amended and modified wherever necessary, even though not specifically addressed herein, so as to conform to the amendments and modifications contained in this Agreement.

5. Except as modified hereby, all of the provisions of the Original Agreement are hereby ratified and confirmed and shall continue in full force and effect.

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Omnibus Agreement in multiple counterparts, each of which shall be deemed an original, as of the date and year first above written.

RIO VISTA ENERGY PARTNERS, L.P.

By: RIO VISTA GP LLC,
On behalf of itself and on behalf of
Partnership as its General Partner

By: Richard Shore, Jr.

Name: Richard Shore, Jr.

Title: President

RIO VISTA OPERATING PARTNERSHIP L.P.

By: RIO VISTA OPERATING GP LLC

By: RIO VISTA ENERGY PARTNERS
L.P., its sole member

By: RIO VISTA GP LLC

By: Richard Shore, Jr.

Richard Shore, Jr., President

PENN OCTANE CORPORATION

By: Jerome B. Richter

Name: Jerome B. Richter Title: Chief Executive Officer

PURCHASE CONTRACT

BETWEEN

PENN OCTANE CORPORATION

"SELLER"

AND

RIO VISTA OPERATING PARTNERSHIP L.P.

"BUYER"


ARTICLE I   QUANTITY OF LPG . . . . . . . . . . . . . . . . . . . . . . .  4

ARTICLE II. TERM. . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4

    Section 2.1  Term . . . . . . . . . . . . . . . . . . . . . . . . . .  4

    Section 2.2  Termination. . . . . . . . . . . . . . . . . . . . . . .  4

ARTICLE III PRICE . . . . . . . . . . . . . . . . . . . . . . . . . . . .  5

ARTICLE IV. TAXES . . . . . . . . . . . . . . . . . . . . . . . . . . . .  5

ARTICLE V POINT OF DELIVERY, FACILITIES AND OWNERSHIP AND
          CONTROL OF LPG. . . . . . . . . . . . . . . . . . . . . . . . .  5

    Section 5.1 Point of Delivery; Facilities . . . . . . . . . . . . . .  5

    Section 5.2 Ownership and Control of LPG. . . . . . . . . . . . . . .  5

ARTICLE VI.  DELIVERY PRESSURE. . . . . . . . . . . . . . . . . . . . . .  6

ARTICLE VII. NOTICES. . . . . . . . . . . . . . . . . . . . . . . . . . .  6

    Section 7.  Notices . . . . . . . . . . . . . . . . . . . . . . . . .  6

    Section 7.2 Change of Address . . . . . . . . . . . . . . . . . . . .  6

ARTICLE VIII. ASSIGNMENT. . . . . . . . . . . . . . . . . . . . . . . . .  6

ARTICLE IX.   GENERAL TERMS AND CONDITIONS. . . . . . . . . . . . . . . .  7

EXHIBITS

Exhibit A - General Terms and Conditions


PURCHASE CONTRACT

THIS PURCHASE CONTRACT (this "Contract") is made and entered into effective as of the 1st day of October, 2004, by and between PENN OCTANE CORPORATION, a Delaware corporation (hereinafter called "Seller"), and RIO VISTA OPERATING PARTNERSHIP L.P., a Delaware limited partnership (hereinafter called "Buyer"):

W I T N E S S E T H:

WHEREAS, Seller desires to sell and deliver to Buyer and Buyer desires to purchase and receive from Seller liquefied petroleum gas ("LPG"), in the quantities and upon the terms and conditions hereinafter set forth;

WHEREAS, the Conflicts Committee of Rio Vista GP LLC has approved of the terms and conditions of this Contract;

NOW, THEREFORE, in consideration of the premises, and of the mutual covenants and agreements contained herein, and the general terms and provisions hereof, Buyer and Seller agree as follows:

ARTICLE I.
QUANTITY OF LPG

Seller agrees to sell and deliver to Buyer and Buyer agrees to purchase and receive from Seller a monthly volume of LPG equal to the total amount of LPG per month that Buyer sells or otherwise distributes using, in whole or in part, any of the Contributed Assets to the extent Seller is able to supply quantities of LPG sufficient for Buyer's needs. Notwithstanding anything herein to the contrary, Buyer shall have no obligation to purchase LPG from Seller in the event the distribution of such LPG by Buyer to its customers would not require the use, in whole or in part, of any of the Contributed Assets. In addition, to the extent Seller does not or cannot supply quantities of LPG sufficient for Buyer's needs, Buyer may purchase LPG from other suppliers during the period that Seller does not or cannot supply quantities of LPG sufficient for Buyer's needs without any obligation to Seller hereunder.

ARTICLE II.
TERM

Section 2.1 Term. This Contract shall be effective as of the 1st day of October, 2004, and, subject to the provisions of this Contract, shall continue and remain in full force and effect for so long as the earlier to occur of (i) Seller ceases to have the right to access the Seadrift Pipeline and (ii) Buyer ceases to use, in whole or in part, any of the Contributed Assets for the sale of LPG.

Section 2.2 Termination. In the event Buyer takes no LPG under this Contract for thirty (30) consecutive Days for any reason whatsoever other than force majeure, Seller shall have the right, at its option, exercisable at any time within fifteen (15) Days following such thirty (30) consecutive Day period, to terminate this Contract by delivering to Buyer written notice of termination. In the event Seller so elects to terminate this Contract, such termination shall be


effective as of 7:00 o'clock a.m. Central Time on the first Day of the Month next following the date of delivery of such notice to Buyer, whereupon the parties hereto shall be relieved of all liabilities and obligations hereunder except for liabilities and obligations of the parties that shall have accrued as of such date of termination. In the event Seller does not or cannot supply quantities of LPG sufficient for Buyer's needs for thirty (30) consecutive Days for any reason whatsoever other than force majeure, Buyer shall have the right, at its option, exercisable at any time within fifteen (15) Days following such thirty (30) consecutive Day period, to terminate this Contract by delivering to Seller written notice of termination. In the event Buyer so elects to terminate this Contract, such termination shall be effective as of 7:00 o'clock a.m. Central Time on the first Day of the Month next following the date of delivery of such notice to Seller, whereupon the parties hereto shall be relieved of all liabilities and obligations hereunder except for liabilities and obligations of the parties that shall have accrued as of such date of termination.

ARTICLE III.
PRICE

Subject to the provisions of this Contract, the amount payable by Buyer to Seller for each Gallon of LPG purchased hereunder each Month shall equal the Purchase Price.

ARTICLE IV.
TAXES

Seller shall pay or cause to be paid all taxes and assessments imposed on Seller with respect to the LPG delivered hereunder prior to its delivery to Buyer, and Buyer shall pay or cause to be paid all taxes and assessments imposed upon Buyer with respect to LPG delivered hereunder after its receipt by Buyer. Neither party shall be responsible or liable for any taxes or other statutory charges levied or assessed against any of the facilities of the other party used for the purpose of carrying out the provisions of this Contract.

ARTICLE V.
POINT OF DELIVERY, FACILITIES AND OWNERSHIP AND CONTROL OF LPG

Section 5.1 Point of Delivery; Facilities. Seller shall deliver the LPG to Buyer hereunder at the point at which the LPG exits the Seadrift Pipeline and is delivered into Buyer's facilities at its Brownsville, Texas terminal or any other point which employs the use of the Contributed Assets. Buyer shall be responsible for arranging for Buyer or its designee, to receive delivery of LPG sold hereunder to Buyer at the Delivery Point into Buyer's or its designee's gathering system.

Section 5.2 Ownership and Control of LPG. Title to the LPG sold and delivered hereunder shall pass to Buyer at the Delivery Point. As between the parties hereto, Seller shall be in control and possession of the LPG and responsible for any damage or injury caused thereby until same shall have been delivered to Buyer, after which delivery Buyer shall be deemed to be in exclusive control and possession thereof and responsible for any injury or damage caused thereby.


ARTICLE VI.
DELIVERY PRESSURE

The LPG delivered or caused to be delivered hereunder by Seller to Buyer or its designee(s) at the Delivery Point shall be delivered at a pressure sufficient to enter the facilities at such point of Buyer or its designee(s).

ARTICLE VII.
NOTICES

Section 7.1 Notices. Every notice, consent, approval, communication, request or reply which is required or which may be given by either party to the other under the terms of this Contract must be in writing, and may be effected by actual delivery to the party to be notified, by depositing such notice in the United States mail, postage prepaid, registered or certified mail, and addressed to the party to be notified with return receipt requested, or by facsimile transmission. Every notice deposited in the United States mail as hereinabove authorized shall, in the absence of a strike, lock-out, boycott or other labor dispute affecting the delivery of United States mail, be effective three (3) days following the date on which it is so deposited. Notice given by facsimile transmission shall be effective on completion and confirmation of the facsimile transmission. Notice given in any other manner shall be effective only if and when received by the party to be notified. For purposes of notice, the addresses of the parties, until changed as hereinafter provided, shall be as follows:

Seller       Penn Octane Corporation
             77-530 Enfield Lane, Building D
             Palm Desert, CA 92211
             Attn:  Jerome B. Richter, President
             Facsimile:  (760) 772-8588

Buyer        Rio Vista Operating Partnership L.P.
             820 Gessner Road, Suite 1285
             Houston, Texas 77024
             Attn:  General Partner
             Facsimile:  (713) _____________

Section  7.2     Change  of  Address.  Each  of  the parties shall have the

right, from time to time, to change its address, and each shall have the right to specify as its address any other address within the United States of America by delivering to the other party not less than ten (10) days' prior notice in writing of such new address.

ARTICLE VIII.
ASSIGNMENT

All the terms, conditions and provisions of this Contract shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns; provided, however, no assignment of this Contract by either party shall be effective or binding until a copy of such assignment has been furnished to the other party.


ARTICLE IX.
GENERAL TERMS AND CONDITIONS.

Annexed hereto as a part hereof are General Terms and Conditions of this Contract which General Terms and Conditions constitute a part of this Contract and the terms and provisions hereof to the same extent as if written in full in the body hereof.

(Signatures on following page)


IN WITNESS WHEREOF, the parties hereto have executed this Contract in multiple counterparts, each of which shall be deemed an original but all of which constitute one and the same instrument as of the date first above mentioned.

"SELLER"

PENN OCTANE CORPORATION

By: /s/ Jerome B. Richter
   ---------------------------------
   Jerome B. Richter, Chief
   Executive Officer

"BUYER"

RIO VISTA OPERATING PARTNERSHIP L.P.

By: RIO VISTA OPERATING GP LLC,
Its General Partner

By:/s/ Richard Shore, Jr.
   ---------------------------
       Richard Shore, Jr.,
       President


EXHIBIT A

GENERAL TERMS AND CONDITIONS

ARTICLE I.

DEFINITIONS

1.1 For the purpose of this Contract, the following terms shall have the meanings ascribed thereto unless their use in context is specifically to the contrary:

(a) Day - That period of time consisting of twenty-four (24) consecutive hours beginning at 7:00 a.m. Central Time.

(b) COGS - is the average cost to Seller per Gallon of LPG on a monthly basis of all LPG supplies obtained by Seller, including the base cost per Gallon of LPG, costs to mix the product, premiums/discounts paid to suppliers for LPGs, mercaptain, testing and inspection costs.

(c) Contributed Assets - shall have the meaning set forth in that certain Contribution, Conveyance and Assumption Agreement dated September 16, 2004 between Seller and Buyer.

(d) ECCPL - the twelve inch pipeline to which the Seller has access and which connects ExxonMobil Corporation's Viola valve station in Nueces County, Texas to the inlet of the King Ranch Gas Plant.

(e) Gallon - 231 cubic inches or 0.133681 cubic feet of liquid at sixty
(60) degrees Fahrenheit and at the equilibrium vapor pressure of the liquid.

(f) Margin Allocation Amount - is the product of (i) the quotient of (a) the difference of Revenues minus COGS divided by (b) the Total LPG Gallons, multiplied by (ii) the quotient of (c) Penn Costs divided by (d) Total Costs.

(g) Month - A chart accounting month commencing at 7:00 a.m. on the first day of the chart accounting month and ending at 7:00 a.m. on the first day of the following chart accounting month.

(h) OPIS - the Oil Price Information Service.

(i) Penn Costs - All costs of Seller on a per Gallon of LPG basis associated with the ownership or lease and operation of assets related to bringing LPG from suppliers to the Delivery Point. These costs principally relate to all variable charges for use of the ECCPL (including minimum thruput charges), the Seadrift Pipeline (including minimum fixed rental charges), minimum Markham storage reservation fees, utilities, trucking costs, insurance costs and

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depreciation. Penn Costs shall also include all indirect selling, general and administrative costs (excluding amounts paid by Buyer). In determining Penn Costs, only cost items paid in cash or to be paid in cash plus depreciation and amortization excluding interest and income taxes, gains/losses on disposal of assets shall be included.

(j) Point of Delivery and Delivery Point - the point of delivery as described in Section 5.1 of the Contract.

(k) Purchase Price - is the sum of the Margin Allocation Amount and the Product Price Allocation.

(l) Product Price Allocation - the average monthly per Gallon price of LPG in accordance with Buyer specifications (generally 90% propane and 10% butane) based on the price quoted for the month average of Mont Belvieu non-tet propane per OPIS and the month average price for Mont Belvieu non-tet normal butane per OPIS.

(m) Revenues - Total proceeds per Gallon of LPG to Buyer from the sale of LPG supplied by Seller.

(n) Rio Vista Costs - All costs to Buyer on a per Gallon of LPG basis associated with ownership or lease and operation of assets employed by Buyer to bring LPG supplied by Seller from the Delivery Point to Buyer's customers. These costs principally relate to the costs of operating the Brownsville terminal facility, the US-Mexico pipelines and the Matamoros terminal facility and any other asset brought on-line in the future which is put into operation for the purpose of enhancing or providing sales of LPG to customers from LPG supplies provided by Seller. Rio Vista Costs include payroll costs, rent, insurance, utilities, repairs and maintenance and depreciation. Rio Vista Costs shall also include all indirect selling, general and administrative costs (including costs allocated from Seller, including costs incurred as a result of the creation of Rio Vista Energy Partners L.P. as a publicly traded limited partnership). In determining Rio Vista Costs, only costs items paid in cash or to be paid in cash plus depreciation and amortization excluding interest and income taxes, gains/losses on disposal of assets shall be included.

(o) Seadrift Pipeline - an approximately 132 mile pipeline which is leased by Seller from the Seadrift Corporation and connects ExxonMobil Corporation's King Ranch Gas Plant in Kleberg County, Texas and Duke Energy's La Gloria Gas Plant in Jim Wells County, Texas to Buyer's Brownsville, Texas terminal facility.

(p) Total Costs - The sum of the Penn Costs and the Rio Vista Costs calculated on a monthly basis.

(q) Total LPG Gallons - is the total number of Gallons of LPG sold by Buyer from supplies of LPG provided by Seller in any one month calculation period.

ARTICLE II.

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QUALITY

Seller agrees that the LPG delivered hereunder shall be of merchantable quality meeting the pressure and quality specifications of customers of Buyer. Buyer shall not be obligated to purchase any LPG which fails to meet the foregoing contract quality specifications. If LPG does not meet such specifications and Buyer desires not to purchase LPG, Seller will be given a 15 day written notice of such intent. Except as hereinafter expressly provided, Buyer shall be obligated to purchase all LPG tendered by Seller hereunder, whether or not such LPG meets the quality specifications of any particular third party purchaser or transporter, so long as such LPG meets the foregoing contract quality specifications. Notwithstanding the foregoing, in the event (a) LPG delivered by Seller to Buyer hereunder is unmarketable and, such LPG, when blended together with LPG from any other sources available to Buyer that exceeds the quality of Seller's LPG, for purposes of improving the overall quality of Seller's LPG, is still unmarketable, and (b) Buyer reasonably demonstrates to Seller's satisfaction that Buyer has made reasonable efforts to market the LPG but has been unable to market the LPG due specifically to the quality of Seller's LPG, then Buyer shall be relieved from its obligation to purchase and take the portion of Seller's LPG which is unmarketable but only for the period of time such LPG remains unmarketable. In the event that such LPG remains unmarketable for a period of ninety (90) days, Seller's obligation to sell and deliver to Buyer and Buyer's obligation to purchase and receive hereunder the portion of Seller's LPG that is unmarketable shall cease and Seller shall be entitled to dispose of such LPG to any third party or parties free and clear of any claim by Buyer hereunder.

ARTICLE III.

MEASUREMENT

3.1 The unit of volume for purposes of measurement of LPG delivered hereunder shall be one (1) Gallon. All fundamental constants, observations, records and procedures involved in the determining and/or verifying of the quality and other characteristics of LPG delivered hereunder shall, unless otherwise specified herein, be in accordance with the standards and methods prescribed in Gas Measurement Committee Report No. 3, dated April, 1955, of the American Gas Association as now and from time to time amended.

3.2 The temperature of the LPG flowing through the meter or meters shall be assumed to be sixty (60) degrees Fahrenheit, but may be determined by continuous use of a recording thermometer installed by Seller (if deemed necessary by Buyer and at Buyer's expense) so that it will properly record the temperature of the LPG flowing through the meter or meters. The arithmetical average of the temperatures recorded while LPG is passing through the meter or meters in each chart period shall be used in computing measurements for that chart period.

3.3 The specific gravity of the LPG flowing through the meter or meters shall be assumed to be .600; however, at Buyer's option and expense, the specific gravity may be determined by use of a sampling device, connected so as to collect a representative sample of the

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LPG delivered hereunder. The specific gravity of the LPG sample will be determined by calculation from a fractional analysis obtained with a chromatograph. The specific gravity will be calculated from the fractional analysis using data in the most up-to-date table, "Physical Constants of Paraffin Hydrocarbons," published by the Natural LPG Processors Association. The specific gravity so determined will be used in calculating LPG deliveries for the Month during which the sample is collected.

3.4 The reading, calibrating and adjustment of such equipment and instruments on which quantities of LPG delivered hereunder are determined and the changing of charts shall be done by employees, agents or representatives of Buyerr. Upon request of Seller, Buyer shall submit to Seller records and charts from such equipment, subject to return by Seller within twenty (20) days after receipt thereof. The charts and records shall be kept on file for a period of three (3) years for the mutual use of the parties hereto.

3.5 At least once each year Buyer, or its affiliates, shall test and calibrate the meter and instruments or cause the same to be tested and calibrated consistent with prior practices. Buyer shall give Seller notice of the time of all tests sufficiently in advance of holding same so that Seller may conveniently have Seller's representative present; however, if Seller's representative is not present, Buyer or a third party acting for Buyer may proceed with the test.

3.6 If the metering equipment in the aggregate is found to be inaccurate by two percent (2%) or more, registrations thereof and any payments based upon such registrations shall be corrected at the rate of such inaccuracy for any period which is definitely known or agreed upon, then for a period extending back one-half (1/2) of the time elapsed since the last test not exceeding, however, fifteen (15) days. Following any test, any metering equipment found to be inaccurate to any degree shall be adjusted immediately to record accurately.

3.7 If for any reason any meter, scale or other system of measurement is out of service or out of repair so that the quantity of LPG received and/or sold by Buyercannot be ascertained or computed from the reading thereof, the quantity of LPG so received and/or sold during the period the system of measurement is out of repair shall be estimated and agreed upon by the parties hereto upon the basis of the best available data, using the first of the following methods which is feasible:

(a) by using the registration of any check measuring equipment of Buyer if installed and accurately registering;

(b) by correcting the error if the percentage or amount of error is ascertainable by calibration, test or mathematical calculation;

(c) by estimating the quantity of purchases during preceding periods under similar conditions when the meter was registering accurately.

3.8 For the purpose of measurement and meter calibration, the atmospheric pressure shall be assumed to be constant at fourteen and seven-tenths (14.7) psia.

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3.9 The measurement hereunder shall be corrected for deviation from Boyle's law at the pressure and temperature under which LPG is delivered hereunder.

3.10 It is agreed that the value of the EXPANSION FACTOR, REYNOLDS NUMBER FACTOR, SUPERCOMPRESSABILITY FACTOR and MANOMETER FACTOR (where Mercury type orifice meters are used) shall be actual values.

ARTICLE IV.

BILLING AND PAYMENT

Buyer shall render to Seller on or before the tenth day of each month a statement of the quantity of LPG (in terms of Gallons) purchased by Buyer from Seller during the preceding Month or for which payment is due, and the amount payable. Buyer shall make payment to Seller for LPG received and/or sold during the preceding Month upon Seller's receipt of the proceeds from the sales of such LPG. Such payments shall be made by wire transfer of immediately available funds to the bank account of Seller specified by Seller to Buyer from time to time pursuant to Article VII of the Contract. Accounting shall be by Buyer, and billings for payment shall be accompanied by a statement showing such calculations and adjustments, if any, as were used to arrive at the amount set out.

ARTICLE V.

WARRANTY OF TITLE

Seller warrants title to all LPG delivered hereunder by Seller, that Seller has the right to sell the same and that such LPG is free from liens (other than liens in favor of RZB Finance LLC) and adverse claims of every kind. Seller will pay all royalties, taxes and other sums due on production of the LPG delivered hereunder. Seller further warrants that the LPG delivered hereunder is free and clear of any prior contract or dedication to any third party that limits or restricts the right of Seller to sell LPG to Buyer hereunder, or that gives such third party a claim to either the proceeds paid or a claim that a like quantity of LPG be tendered to such third party at a later date. Seller will indemnify and save Buyer harmless against all loss, damage and expense of every character on account of adverse claims to the LPG delivered by Seller or of royalties, taxes, payments or other charges thereon applicable before or upon delivery to Buyer. If Seller's title is questioned or involved in any legal action, Buyer may withhold payment of sums due hereunder up to the amount of the claim until title is freed from such question or such action is finally determined, or until Seller furnishes either bond with surety or an escrow arrangement satisfactory to Buyer and conditioned to save Buyer harmless.

ARTICLE VI.

REGULATORY BODIES

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This Contract shall be subject to all valid and applicable laws, rules and regulations of any duly constituted governmental body having jurisdiction herein. Buyer does not require any governmental authority or approval to enter into this Contract or to accept the delivery of LPG from Seller hereunder. If at any time there is a new law, rule or regulation, or changed interpretation of any existing law, rule or regulation that requires Buyer to obtain any governmental approval or authorization, Buyer will notify Seller of the requirement and will furnish Seller with any application filed, the evidence to support the application and of the order or authorization entered.

ARTICLE VII.

FORCE MAJEURE

In the event either party hereto is rendered unable, wholly or in part, by force majeure, to carry out its obligations under this Contract, other than to make payments due hereunder, then on such party's giving notice and reasonable full particulars of such force majeure in writing or by telecopy to the other party as soon as possible after the occurrence of the cause relied upon, the obligations of the party giving notice, so far as they are affected by such force majeure, shall be suspended during, but only during, the continuance of any inability so caused. The term "force majeure," as used herein, shall mean acts of God, strikes, lockouts, acts of the public enemy, wars, blockades, insurrections, riots, epidemics, landslides, lightning, earthquakes, hurricanes or the threat thereof, fires, storms, floods, washouts, arrest and restraints of rulers of people, civil disturbances, the freezing of wells or lines of pipe, requisitions, directives, diversions, embargoes, priorities, expropriations of government or governmental authorities, legal or de facto, whether purporting to act under some constitution, decree, law or otherwise, failure of pipelines, facilities or lines of pipe provided such failure of pipelines, facilities or lines of pipe is not reasonably within the control of the party claiming suspension, the partial or entire failure of LPG wells, and the inability to acquire, or the delays in acquiring at reasonable cost and after the exercise of reasonable diligence, such servitudes, right of way grants, permits, licenses, approvals and authorizations by regulatory bodies, and/or such supplies and materials (or permission from regulatory bodies to use supplies and materials on hand), as may be necessary in order that obligations assumed hereunder may be lawfully performed in the manner herein contemplated. Upon the occurrence of an event constituting force majeure, the same shall, so far as possible, be remedied with all reasonable dispatch. The settlement of strikes or other labor difficulties shall be entirely within the discretion of the party having the difficulty, and the above requirement that any force majeure shall be remedied with all reasonable dispatch shall not require the settlement of strikes or other labor difficulties by acceding to the demands of any opposing party therein when such course is inadvisable in the discretion of the party having the difficulty.

ARTICLE VIII.

INDEMNITY

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Buyer shall indemnify, defend and hold Seller harmless from and against all loss, cost and expense, including court costs and attorney's fees, for any claims, suits, judgments, demands, actions or liability growing out of the operations conducted hereunder by Buyer or arising while the LPG is in Buyer's exclusive control and possession. Likewise, Seller shall indemnify, defend and hold Buyer harmless from and against any loss, cost and expense, including court costs and attorney's fees, for any claims, suits, judgments, demands, actions or liability growing out of Seller's operations of its wells, leases, equipment, pipelines and other facilities and appurtenances thereto or arising while the LPG is in Seller's exclusive control and possession.

ARTICLE IX.

MISCELLANEOUS

9.1 Entirety - This Contract contains the entire agreement between the parties and there are no oral promises, agreements or warranties affecting it.

9.2 Titles - The numbering and titling of particular provisions of this Contract are for the purpose of facilitating administration and shall not be construed as having any substantive effect on the terms of this Contract.

9.3 Waiver - Waiver of any breach or failure to enforce any of the terms and conditions of this Contract at any time shall not in any way affect, limit or waive either party's right thereafter to enforce and compel compliance with every term and condition hereof.

9.4 Time of Essence - Time is of the essence in this Contract in all respects.

9.5 Preparer - This Contract was prepared jointly by the parties hereto and not by either party to the exclusion of the other.

9.6 Severability - In the event that any clause or provision in this Contract shall, for any reason, be deemed illegal, invalid or unenforceable, the remaining provisions and clauses shall not be affected, impaired or invalidated and shall remain in full force and effect. In lieu of such illegal, invalid or unenforceable provision, there shall be added automatically as a part of this Contract a provision as similar in terms to such illegal, invalid or unenforceable provision as may be possible and be legal, valid and enforceable.

9.7 Governing Law - As to all matters of construction and interpretation, this Contract shall be interpreted, construed and governed by the laws of the State of Texas, excluding conflicts of law principles that might require the application of the laws of another jurisdiction.

9.8 Damages - Neither party shall be liable to the other for any indirect, incidental, consequential or punitive damages which may occur, in whole or in part, as a result of a party's performance or non-performance of any of the terms and conditions of this Contract.

End of General Terms and Conditions

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THIS OPTION AND THE LIMITED LIABILITY COMPANY INTERESTS PURCHASABLE UPON EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR UNDER ANY STATE SECURITIES LAWS. IT MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT AS TO THE SECURITIES UNDER SAID ACT OR AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

UNIT PURCHASE OPTION

Void after July 10, 2006

Option No. 1 July 10, 2003

FOR VALUE RECEIVED and pursuant to the terms of a letter agreement dated November 29, 2002, between Shore Capital LLC and Penn Octane Corporation, a Delaware corporation ("Penn Octane"), and a resulting employment agreement dated May 13, 2003, between Penn Octane and Richard Shore, Jr., the undersigned, Penn Octane, hereby certifies that Shore Capital LLC (the "Holder"), or assigns, is entitled, subject to the terms set forth below, to purchase from Penn Octane after the date (the "Distribution Date") Penn Octane completes the distribution (the "Distribution") to its stockholders of all of the outstanding common units of Rio Vista Energy Partners L.P., a Delaware limited partnership ("Rio Vista"), and before 5:00 P.M. New York time, on July 10, 2006 (the "Expiration Date") 25% of the outstanding Units (as defined below) of Rio Vista GP LLC, a Delaware limited liability company (the "Company") for a purchase price per Unit (the "Exercise Price") equal to the number of Units to be purchased divided by the pro rata portion of the tax basis capital of Rio Vista immediately following the Distribution.

As used herein the following terms, unless the context otherwise requires, have the following respective meanings:

(a) The term "Company" includes any corporation that shall succeed to or assume the obligations of the Company.

(b) The term "Exercise Price" shall have the meaning ascribed to such term in the first paragraph hereof.

(c) The term "Limited Liability Company Agreement" shall mean the Amended and Restated Limited Liability Company Agreement of the Company dated September 8, 2004.

(c) The term "Purchase Price" shall mean the amount equal to the product of the Exercise Price and the number of Units to be purchased upon the full exercise of this Option.

(d) The term "Units" shall have the meaning ascribed to such term in the Limited Liability Company Agreement.

1. Exercise of Option. This Option may be exercised in full by the Holder hereof at any time after the Distribution Date and before the Expiration Date by surrender of this Option,

with the form of subscription, addendum agreement to the limited liability company agreement of the Company and the Voting Agreement attached hereto duly executed by such Holder, to the Company and Penn Octane at their respective principal offices, accompanied by payment of the Purchase Price. The Purchase Price shall be paid by cash or check payable to the order of Penn Octane Corporation.

2. When Exercise Effective. The exercise of this Option shall be deemed to have been effected immediately prior to the close of business on the business day on which this Option is surrendered as provided in Section 1 and the documents referenced in Section 1 are duly executed and delivered as provided in
Section 1, and at such time the Holder shall be deemed to be the record holder of such Units for all purposes.

3. Delivery on Exercise. As soon as practicable after the exercise of this Option in full, and in any event within ten (10) business days thereafter, Penn Octane at its expense (including the payment by it of any applicable issue taxes) will cause to be delivered to the holder hereof a certificate or certificates for the number of Units to which such holder shall be entitled on such exercise.

4. Investment Intent. Unless a current registration statement under the Securities Act of 1933, as amended (the "Securities Act"), shall be in effect with respect to the securities to be purchased upon exercise of this Option, the Holder hereof, by accepting this Option, covenants and agrees that, at the time of exercise hereof, and at the time of any proposed transfer of securities acquired upon exercise hereof, such Holder will deliver to the Company and Penn Octane a written statement that the securities acquired by the Holder are for such Holder's own account, and are not acquired with a view to, or for sale in connection with, any distribution thereof (or any portion thereof) except pursuant to current registration statement under the Securities Act or an available exemption from registration.

5. Transfer. This Option is not transferable without the prior written consent of Penn Octane.

6. No Rights or Liability as a Member. This Option does not entitle the Holder hereof to any voting rights or other rights as a Member (as defined in Limited Liability Company Agreement). No provisions hereof and no enumeration herein of the rights or privileges of the Holder hereof shall give rise to any liability of such holder as a Member of the Company. The Units to be purchased pursuant to this Option are subject to the terms of the Limited Liability Company Agreement. The Holder shall not be deemed to be a Member and shall not have any rights of a Member or rights of an assignee from a Member with respect to, any Units subject to this Option unless and until the Holder has satisfied all requirements for exercise of this Option pursuant to its terms. Before receiving the Units subject to this Option, the Holder shall take such action and execute such documents as the Company and Penn Octane may require to become a Member of the Company.

7. Damages. Penn Octane recognizes and agrees that the Holder hereof will not have an adequate remedy if Penn Octane fails to comply with the terms of this Option and that damages will not be readily ascertainable, and Penn Octane expressly agrees that, in the event of such failure, it shall not oppose an application by the Holder of this Option or any other person

2

entitled to the benefits of this Option requiring specific performance of any and all provisions hereof or enjoining the Penn Octane from continuing to commit any such breach of the terms hereof.

8. Notices. All notices and other communications required or permitted hereunder shall be in writing and sent (a) by telecopy if the sender on the same day sends a confirming copy of such notice by a recognized overnight delivery service (charges prepaid), or (b) by first class mail, or (c) by a recognized overnight delivery service (with charges prepaid), addressed (1) if to the Holder of this Option, at such Holder's address as it appears in the records of Penn Octane (unless otherwise indicated by such Holder), (2) if to Penn Octane, at its office at 77-530 Enfield Lane, Building D, Palm Desert, CA 92211, Attention: Chief Executive Officer, or at such other address as Penn Octane shall have furnished to the Holder of the Option in writing or (3) if to the Company, at its office at 820 Gessner Road, Suite 1285, Houston, Texas 77024 or at such other address as the Company or Penn Octane shall have furnished to the Holder of the Option in writing

9. Payment of Taxes. Penn Octane shall pay all transfer taxes and other governmental charges (not including state and federal income taxes) that may be imposed in respect to the issue or delivery of the Units purchased upon the exercise of this Option. At the time this Option is exercised, in whole or in part, or at any time thereafter as requested by Penn Octane, Holder hereby authorizes withholding from payroll and any other amounts payable to Holder, and otherwise agrees to make adequate provision for, any sums required to satisfy the federal, state, local and foreign tax withholding obligations of Penn Octane or an affiliate, if any, which arise in connection with this Option. This Option is not exercisable unless the tax withholding obligations of Penn Octane and/or any affiliate are satisfied. Accordingly, Holder may not be able to exercise this Option when desired even though this Option is vested, and Penn Octane shall have no obligation to issue a certificate for such Units or release such Units from any escrow provided for herein.

10. Governing Law. All issues and questions concerning the construction, validity, enforcement and interpretation of this Option and the attachments hereto shall be governed by, and construed in accordance with, the laws of the State of Texas without giving effect to any choice of law or conflict of law rules or provisions (whether of the State of Texas or any other jurisdiction) that would cause the application of the laws of any jurisdiction other than the State of Texas. In furtherance of the foregoing, the internal law of the State of Texas shall control the interpretation and construction of this Option (and all attachments hereto), even though under that jurisdiction's choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

11. Consent to Jurisdiction.

(a) Each of the parties hereto hereby irrevocably and unconditionally submits, for itself and its property, to the exclusive jurisdiction of any Texas state court or federal court o the United States of America sitting in Houston, Texas, and any appellate court from any thereof, in any action or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby or for recognition or enforcement of any judgment relating thereto, and each of the parties hereto hereby irrevocably and unconditionally agrees that all claims in respect

3

of any such action or proceeding may be heard and determined in such Texas state court or, to the extent permitted by law, in such federal court. Each of the parties hereto agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law.

(b) Each of the parties hereto hereby irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection which it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Option or the transactions contemplated hereby in any Texas state or federal court. Each of the parties hereto hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such action or proceeding in any such court.

(c) Each party to this Option irrevocably consents to service of process in the manner provided for notices in Section 8. Nothing in this Option will affect the right of any party to this Option to serve process in any other manner permitted by law.

12. Waiver of Jury Trial.

(a) EACH PARTY ACKNOWLEDGES AND AGREES THAT ANY CONTROVERSY WHICH MAY ARISE UNDER THIS OPTION IS LIKELY TO INVOLVE COMPLICATED AND DIFFICULT ISSUES, AND THEREFORE IT HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF OR RELATING TO THIS OPTION OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY.

(b) EACH PARTY CERTIFIES AND ACKNOWLEDGES THAT (i) NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, (ii) IT UNDERSTANDS AND HAS CONSIDERED THE IMPLICATIONS OF SUCH WAIVER, (iii) IT MAKES SUCH WAIVER VOLUNTARILY, AND (iv) IT HAS BEEN INDUCED TO ENTER INTO THIS OPTION BY, AMONG OTHER THINGS, THE MUTUAL WAIVER AND CERTIFICATIONS IN THIS SECTION 12.

13. Miscellaneous. This Option and any term hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of such change, waiver, discharge or termination is sought. The headings in this Option are for purposes of reference only, and shall not limit or otherwise affect any of the terms hereof.

PENN OCTANE CORPORATION

By: Jerome B. Richter
Jerome B. Richter, Chief Executive Officer

4

ACKNOWLEDGED AND AGREED TO
WITH RESPECT TO ITS RIGHTS AND
OBLIGATIONS HEREUNDER:

SHORE CAPITAL LLC

By: /s/ Richard Shore, Jr.
    -------------------------------------------
    Richard Shore, Jr., President

5

ATTACHMENT A TO OPTION

FORM OF SUBSCRIPTION

(TO BE SIGNED ONLY ON EXERCISE OF OPTION)

To: PENN OCTANE CORPORATION

The undersigned, the holder of the within Option, hereby irrevocably elects to exercise the purchase rights represented by such Option for, and to purchase thereunder, 25% of the outstanding Units of RIO VISTA GP LLC and herewith makes payment of $___________ therefor,

and requests that the certificates for such units be issued in the name of, and delivered to the undersigned, whose address is________________________ ____________________________________.


(Signature must conform in all respects to name of holder as specified on the face of the Option)



Address

Dated: ________________________

6

ATTACHMENT B TO OPTION

ADDENDUM AGREEMENT TO THE LIMITED LIABILITY COMPANY
AGREEMENT OF RIO VISTA GP LLC

7

ATTACHMENT C TO OPTION

VOTING AGREEMENT

8

THIS OPTION AND THE LIMITED LIABILITY COMPANY INTERESTS PURCHASABLE UPON EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR UNDER ANY STATE SECURITIES LAWS. IT MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT AS TO THE SECURITIES UNDER SAID ACT OR AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

UNIT PURCHASE OPTION

Void after July 10, 2006

Option No. 2 July 10, 2003

FOR VALUE RECEIVED, the undersigned, PENN OCTANE CORPORATION, a Delaware corporation ("Penn Octane"), hereby certifies that Jerome B. Richter (the "Holder"), or assigns, is entitled, subject to the terms set forth below, to purchase from Penn Octane after the date (the "Distribution Date") Penn Octane completes the distribution (the "Distribution") to its stockholders of all of the outstanding common units of Rio Vista Energy Partners L.P., a Delaware limited partnership ("Rio Vista"), and before 5:00 P.M. New York time, on July 10, 2006 (the "Expiration Date") 25% of the outstanding Units (as defined below) of Rio Vista GP LLC, a Delaware limited liability company (the "Company"), for a purchase price per Unit (the "Exercise Price") equal to the number of Units to be purchased divided by the pro rata portion of the tax basis capital of Rio Vista immediately following the Distribution.

As used herein the following terms, unless the context otherwise requires, have the following respective meanings:

(a) The term "Company" includes any corporation that shall succeed to or assume the obligations of the Company.

(b) The term "Exercise Price" shall have the meaning ascribed to such term in the first paragraph hereof.

(c) The term "Limited Liability Company Agreement" shall mean the Amended and Restated Limited Liability Company Agreement of the Company dated September 8, 2004.

(c) The term "Purchase Price" shall mean the amount equal to the product of the Exercise Price and the number of Units to be purchased upon the full exercise of this Option.

(d) The term "Units" shall have the meaning ascribed to such term in the Limited Liability Company Agreement.

1. Exercise of Option. This Option may be exercised in full by the Holder hereof at any time after the Distribution Date and before the Expiration Date by surrender of this Option, with the form of subscription, addendum agreement to the limited liability company agreement of the Company and the Voting Agreement attached hereto duly executed by such Holder, to the Company and Penn Octane at their respective principal offices, accompanied by payment of the

Purchase Price. The Purchase Price shall be paid by cash or check payable to the order of Penn Octane Corporation.

2. When Exercise Effective. The exercise of this Option shall be deemed to have been effected immediately prior to the close of business on the business day on which this Option is surrendered as provided in Section 1 and the documents referenced in Section 1 are duly executed and delivered as provided in
Section 1, and at such time the Holder shall be deemed to be the record holder of such Units for all purposes.

3. Delivery on Exercise. As soon as practicable after the exercise of this Option in full, and in any event within ten (10) business days thereafter, Penn Octane at its expense (including the payment by it of any applicable issue taxes) will cause to be delivered to the holder hereof a certificate or certificates for the number of Units to which such holder shall be entitled on such exercise.

4. Investment Intent. Unless a current registration statement under the Securities Act of 1933, as amended (the "Securities Act"), shall be in effect with respect to the securities to be purchased upon exercise of this Option, the Holder hereof, by accepting this Option, covenants and agrees that, at the time of exercise hereof, and at the time of any proposed transfer of securities acquired upon exercise hereof, such Holder will deliver to the Company and Penn Octane a written statement that the securities acquired by the Holder are for such Holder's own account, and are not acquired with a view to, or for sale in connection with, any distribution thereof (or any portion thereof) except pursuant to current registration statement under the Securities Act or an available exemption from registration.

5. Transfer. This Option is not transferable without the prior written consent of Penn Octane.

6. No Rights or Liability as a Member. This Option does not entitle the Holder hereof to any voting rights or other rights as a Member (as defined in Limited Liability Company Agreement). No provisions hereof and no enumeration herein of the rights or privileges of the Holder hereof shall give rise to any liability of such holder as a Member of the Company. The Units to be purchased pursuant to this Option are subject to the terms of the Limited Liability Company Agreement. The Holder shall not be deemed to be a Member and shall not have any rights of a Member or rights of an assignee from a Member with respect to, any Units subject to this Option unless and until the Holder has satisfied all requirements for exercise of this Option pursuant to its terms. Before receiving the Units subject to this Option, the Holder shall take such action and execute such documents as the Company and Penn Octane may require to become a Member of the Company.

7. Damages. Penn Octane recognizes and agrees that the Holder hereof will not have an adequate remedy if Penn Octane fails to comply with the terms of this Option and that damages will not be readily ascertainable, and Penn Octane expressly agrees that, in the event of such failure, it shall not oppose an application by the Holder of this Option or any other person entitled to the benefits of this Option requiring specific performance of any and all provisions hereof or enjoining the Penn Octane from continuing to commit any such breach of the terms hereof.

2

8. Notices. All notices and other communications required or permitted hereunder shall be in writing and sent (a) by telecopy if the sender on the same day sends a confirming copy of such notice by a recognized overnight delivery service (charges prepaid), or (b) by first class mail, or (c) by a recognized overnight delivery service (with charges prepaid), addressed (1) if to the Holder of this Option, at such Holder's address as it appears in the records of Penn Octane (unless otherwise indicated by such Holder), (2) if to Penn Octane, at its office at 77-530 Enfield Lane, Building D, Palm Desert, CA 92211, Attention: Chief Executive Officer, or at such other address as Penn Octane shall have furnished to the Holder of the Option in writing or (3) if to the Company, at its office at 820 Gessner Road, Suite 1285, Houston, Texas 77024 or at such other address as the Company or Penn Octane shall have furnished to the Holder of the Option in writing.

9. Payment of Taxes. Penn Octane shall pay all transfer taxes and other governmental charges (not including state and federal income taxes) that may be imposed in respect to the issue or delivery of the Units purchased upon the exercise of this Option. At the time this Option is exercised, in whole or in part, or at any time thereafter as requested by Penn Octane, Holder hereby authorizes withholding from payroll and any other amounts payable to Holder, and otherwise agrees to make adequate provision for, any sums required to satisfy the federal, state, local and foreign tax withholding obligations of Penn Octane or an affiliate, if any, which arise in connection with this Option. This Option is not exercisable unless the tax withholding obligations of Penn Octane and/or any affiliate are satisfied. Accordingly, Holder may not be able to exercise this Option when desired even though this Option is vested, and Penn Octane shall have no obligation to issue a certificate for such Units or release such Units from any escrow provided for herein.

10. Governing Law. All issues and questions concerning the construction, validity, enforcement and interpretation of this Option and the attachments hereto shall be governed by, and construed in accordance with, the laws of the State of Texas without giving effect to any choice of law or conflict of law rules or provisions (whether of the State of Texas or any other jurisdiction) that would cause the application of the laws of any jurisdiction other than the State of Texas. In furtherance of the foregoing, the internal law of the State of Texas shall control the interpretation and construction of this Option (and all attachments hereto), even though under that jurisdiction's choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

11. Consent to Jurisdiction.

(a) Each of the parties hereto hereby irrevocably and unconditionally submits, for itself and its property, to the exclusive jurisdiction of any Texas state court or federal court o the United States of America sitting in Houston, Texas, and any appellate court from any thereof, in any action or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby or for recognition or enforcement of any judgment relating thereto, and each of the parties hereto hereby irrevocably and unconditionally agrees that all claims in respect of any such action or proceeding may be heard and determined in such Texas state court or, to the extent permitted by law, in such federal court. Each of the parties hereto agrees that a final judgment in any such action or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other manner provided by law.

3

(b) Each of the parties hereto hereby irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection which it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Option or the transactions contemplated hereby in any Texas state or federal court. Each of the parties hereto hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such action or proceeding in any such court.

(c) Each party to this Option irrevocably consents to service of process in the manner provided for notices in Section 8. Nothing in this Option will affect the right of any party to this Option to serve process in any other manner permitted by law.

12. Waiver of Jury Trial.

(a) EACH PARTY ACKNOWLEDGES AND AGREES THAT ANY CONTROVERSY WHICH MAY ARISE UNDER THIS OPTION IS LIKELY TO INVOLVE COMPLICATED AND DIFFICULT ISSUES, AND THEREFORE IT HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY ARISING OUT OF OR RELATING TO THIS OPTION OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY.

(b) EACH PARTY CERTIFIES AND ACKNOWLEDGES THAT (i) NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, (ii) IT UNDERSTANDS AND HAS CONSIDERED THE IMPLICATIONS OF SUCH WAIVER, (iii) IT MAKES SUCH WAIVER VOLUNTARILY, AND (iv) IT HAS BEEN INDUCED TO ENTER INTO THIS OPTION BY, AMONG OTHER THINGS, THE MUTUAL WAIVER AND CERTIFICATIONS IN THIS SECTION 12.

13. Miscellaneous. This Option and any term hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of such change, waiver, discharge or termination is sought. The headings in this Option are for purposes of reference only, and shall not limit or otherwise affect any of the terms hereof.

PENN OCTANE CORPORATION

By: /s/ Richard Shore, Jr.
    ----------------------------------
    Richard Shore, Jr., President

4

ACKNOWLEDGED AND AGREED TO
WITH RESPECT TO ITS RIGHTS AND
OBLIGATIONS HEREUNDER:

/s/Jerome  B.  Richter
--------------------------------------
Jerome  B.  Richter

5

ATTACHMENT A TO OPTION

FORM OF SUBSCRIPTION

(TO BE SIGNED ONLY ON EXERCISE OF OPTION)

To: PENN OCTANE CORPORATION

The undersigned, the holder of the within Option, hereby irrevocably elects to exercise the purchase rights represented by such Option for, and to purchase thereunder, 25% of the outstanding Units of RIO VISTA GP LLC and herewith makes payment of $___________ therefor,

and requests that the certificates for such units be issued in the name of, and delivered to the undersigned, whose address is ______________________ ________________________________________________.


(Signature must conform in all respects to name of holder as specified on the face of the Option)



Address

Dated: ________________________

6

ATTACHMENT B TO OPTION

ADDENDUM AGREEMENT TO THE LIMITED LIABILITY COMPANY
AGREEMENT OF RIO VISTA GP LLC

7

ATTACHMENT C TO OPTION

VOTING AGREEMENT

8

RIO VISTA ENERGY PARTNERS L.P.
UNIT OPTION AGREEMENT

Void after July 10, 2006

Option No. 1 Date of Grant: July 10, 2003

FOR VALUE RECEIVED and pursuant to the terms of a letter agreement dated November 29, 2002, between Shore Capital LLC and Penn Octane Corporation, a Delaware corporation ("Penn Octane"), and a resulting employment agreement dated May 13, 2003, between Penn Octane and Richard Shore, Jr., the undersigned, RIO VISTA ENERGY PARTNERS L.P., a limited partnership organized and existing under the laws of the State of Delaware, hereby certifies that Shore Capital LLC is entitled, subject to the terms set forth below, to purchase from the Partnership after the completion of the distribution by Penn Octane to its stockholders of all of the outstanding Common Units of the Partnership and before 5:00 P.M. New York time, on July 10, 2006 (the "Expiration Date"), 97,415 Common Units of the Partnership. The purchase price per Common Unit shall be $8.47 (the "Exercise Price").

The details of this Option Agreement (this "Agreement") are as follows:

1. DEFINITIONS.

(a) "AFFILIATE" means, with respect to any specified person, any person that directly or through one or more intermediaries controls or is controlled by or is under common control with the specified person. As used in this definition, the term "control" means the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of a person, whether through ownership of voting securities, by contract or otherwise. For purposes of clarification, Penn Octane Corporation is an Affiliate of the Partnership and the General Partner.

(b) "CODE" means the Internal Revenue Code of 1986, as amended.

(c) "GENERAL PARTNER" means Rio Vista GP LLC, a Delaware limited liability company, and its successors or assigns.

(d) "MANAGER" means a manager of the General Partner under the Delaware Limited Liability Company Act.

(e) "OFFICER" means any person designated by the General Partner as an officer.

(f) "OPTION" means an option to acquire Common Units granted pursuant to this Agreement.

(g) "OPTIONHOLDER" means the person to whom an Option to acquire Common Units is granted pursuant to this Agreement.

(h) "PARTNERSHIP" means Rio Vista Energy Partners L.P., a Delaware limited partnership, and its successors or assigns.

(i) "PARTNERSHIP AGREEMENT" means the limited partnership agreement of the Partnership, as amended.

(j) "PURCHASE PRICE" means the amount equal to the product of the Exercise Price and the number of Common Units to be purchased upon exercise of this Option.

(k) "COMMON UNIT" has the meaning set forth in the Partnership Agreement or any equity interest into which a Common Unit is exchanged or converted.

2. ADMINISTRATION.

(a) ADMINISTRATION BY GENERAL PARTNER. The General Partner shall administer this Agreement. Any interpretation of this Agreement by the General Partner and any decision by the General Partner under this Agreement shall be final and binding on all persons.

(b) POWERS OF GENERAL PARTNER. The General Partner shall have the power, subject to, and within the limitations of, the express provisions of this Agreement:

(i) to construe and interpret this Agreement, and to establish, amend and revoke rules and regulations for its administration; the General Partner, in the exercise of this power, may correct any defect, omission or inconsistency in this Agreement, in a manner and to the extent it shall deem necessary or expedient to make this Agreement fully effective; and

(ii) generally, to exercise such powers and to perform such acts as the General Partner deems necessary or expedient to promote the best interests of the Partnership which are not in conflict with the provisions of this Agreement.

3. NUMBER OF COMMON UNITS, EXERCISE PRICE AND CAPITALIZATION ADJUSTMENTS. The number of Common Units subject to this Option and the exercise price per Common Unit may be adjusted from time to time for capitalization adjustments described in this Section. If any change is made in the Common Units subject to this Agreement, without the receipt of consideration by the Partnership (through conversion, merger, consolidation, reorganization, recapitalization, unit distribution, distribution in property other than cash, Common Units split, liquidating distribution, combination of Common Units, exchange of Common Units, change in structure or other transaction not involving the receipt of consideration by the Partnership), the Common Units subject to this Agreement will be appropriately adjusted in the class(es) and number of securities and price per Common Unit. The General Partner, the determination of which shall be final, binding and conclusive, shall make such adjustments. (The conversion of any convertible securities of the Partnership shall not be treated as a transaction "without receipt of consideration" by the Partnership.)

4. METHOD OF PAYMENT. Payment of the Purchase Price is due in full upon exercise of all or any part of this Option. The Optionholder may elect to make payment of the Purchase Price in cash or by check.

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5. WHOLE COMMON UNITS. This Option may only be exercised for whole Common Units.

6. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary contained herein, this Option may not be exercised unless the Common Units issuable upon exercise of this Option are then registered under the Securities Act or, if such Common Units are not then so registered, the Partnership has determined that such exercise and issuance would be exempt from the registration requirements of the Securities Act. The Partnership shall use its commercially reasonable efforts to register such Common Units under the Securities Act.

7. TERM. The term of this Option commences on the date Penn Octane completes the distribution to its stockholders of all the outstanding Common Units of the Partnership and expires on the Expiration Date.

8. EXERCISE.

(a) Subject to Section 8(c), the Optionholder may exercise this Option during its term by delivering a Notice of Exercise (in a form designated by the General Partner) together with the Purchase Price to the Secretary of the General Partner, or to such other person as the General Partner may designate, during regular business hours, together with such additional documents as the General Partner may then require.

(b) By exercising this Option, the Optionholder agrees that, as a condition to any exercise of this Option, the Partnership or the General Partner may require the Optionholder to enter an arrangement providing for the payment by the Optionholder to the Partnership of any tax withholding obligation of the Partnership, as reasonably determined by the Partnership, arising by reason of
(1) the exercise of this Option, or (2) the disposition of Common Units acquired upon such exercise.

(c) Notwithstanding anything herein to the contrary, during the term of this Option, this Option may only be exercised during the first ten (10) days of the first month of each fiscal quarter of the Partnership and during such other periods as the General Partner may designate in its sole discretion for purposes of minimizing the accounting costs to the Partnership resulting from such exercise.

9. TRANSFERABILITY. This Option is not transferable, except to any Affiliate of the Optionholder, and is exercisable only by the Optionholder or such Affiliate. The transferability of the Common Units issued upon exercise of this Option shall be subject to the conditions, restrictions and limitations set forth in this Agreement, the Partnership Agreement and any other agreements the Optionholder may have with the Partnership.

(a) The provisions of this Section 9 may be waived with respect to any transfer by the Partnership, upon duly authorized action of the General Partner.

(b) Any sale or transfer, or purported sale or transfer, of the Common Units by the Optionholder shall be null and void unless the terms, conditions, and provisions of this Section 9 are observed and followed.

-3-

10. WITHHOLDING OBLIGATIONS

(a) At the time this Option is exercised, in whole or in part, or at any time thereafter as requested by the Partnership, you hereby authorize withholding from payroll and any other amounts payable to you, and otherwise agree to make adequate provision for, any sums required to satisfy the federal, state, local and foreign tax withholding obligations of the Partnership or an Affiliate, if any, which arise in connection with this Option.

(b) This Option is not exercisable unless the tax withholding obligations of the Partnership and/or any Affiliate are satisfied. Accordingly, you may not be able to exercise this Option when desired even though this Option is vested, and the Partnership shall have no obligation to issue a certificate for such Common Units or release such Common Units from any escrow provided for herein.

11. TAX CONSEQUENCES AND CAPITAL ACCOUNT UPON EXERCISE OF OPTION. It is intended that neither the Optionholder, the Partnership nor any of the partners (owners) of the Partnership shall have any federal income tax consequences upon grant of this Option, or, except as described herein, upon exercise of this Option. Additionally, it is intended that the Optionholder shall not be treated as a partner with respect to the Common Units subject to this Agreement until such time as this Option is exercised. It is intended that, upon exercise of this Option, the Optionholder shall include in income ("Exercise Income") in the tax year of exercise an amount equal to the excess, if any, of the fair market value of Common Units on the date of exercise over the sum of the amount the Optionholder has paid or will pay to the Partnership ("Option Consideration") upon the grant and exercise of the Option. It is intended that the Partnership shall be entitled to a deduction equal to the amount of Exercise Income, which, if the Partnership continues to be a partnership for federal income tax purposes, shall be allocated solely to the partners of the Partnership other than the Optionholder to whom the Exercise Income is attributable. Upon exercise of this Option, Optionholder shall receive a positive capital account in the Partnership (assuming the Partnership continues to be classified as a partnership for federal income purposes) equal to the sum of the Exercise Income to the Optionholder and the amount of Option Consideration paid by the Optionholder. Should the federal income tax consequences differ from that described in this section, the General Partner shall have the authority to change the capital account or allocations of income and deduction to the Optionholder as described herein in manner which in its discretion most closely achieves the same economic effect of the consequences described in this Section. Notwithstanding anything herein to the contrary, the General Partner shall have the authority to change the tax reporting described above with respect to the issuance or exercise of this Option or alter the capital accounts or allocations of Partnership items as necessary to preserve or achieve the uniformity of Common Units.

12. NOTICES. Any notices provided for in this Option or this Agreement shall be given in writing and shall be deemed effectively given upon receipt or, in the case of notices delivered by the Partnership to the Optionholder, five
(5) days after deposit in the United States mail, postage prepaid, addressed to the Optionholder at the last address provided to the Partnership.

-4-

13. THIS AGREEMENT; PARTNERSHIP AGREEMENT. This Option is subject to all the provisions of this Agreement, the provisions of which are hereby made a part of this Option, and is further subject to all interpretations, amendments, rules and regulations which may from time to time be promulgated and adopted pursuant to this Agreement, and the Common Units to be delivered are subject to the terms of the Partnership Agreement. In the event of any conflict among Optionholder's rights under the Common Units, this Agreement and the Partnership Agreement, the terms of the Partnership Agreement shall control.

14. MISCELLANEOUS.

(a) AVAILABILITY OF COMMON UNITS. During the term of this Option, the Partnership shall keep available at all times the number of Common Units required to satisfy the Option.

(b) PARTNER RIGHTS. No Optionholder shall be deemed to be partner of the Partnership, or to have any of the rights of a partner or rights of an assignee from a partner with respect to, any Common Units subject to the Option unless and until such Optionholder has satisfied all requirements for exercise of the Option pursuant to its terms.

(c) INVESTMENT ASSURANCES. Unless the Common Units issuable upon exercise of this Option are then registered under the Securities Act, the General Partner may require an Optionholder, as a condition of exercising or acquiring Common Units under the Option, to give written assurances that he is an "accredited investor," as defined in the rules and regulations under the Securities Act. The General Partner may, upon advice of counsel to the General Partner, place legends on Common Units certificates issued under the Option as such counsel deems necessary or appropriate in order to comply with applicable securities laws, including, but not limited to, legends restricting the transfer of the Common Units.

(d) PARTNERSHIP AGREEMENT. Before receiving Common Units, the Optionholder shall take such action and execute such documents as the General Partner may require to become a partner of the Partnership.

IN WITNESS WHEREOF, this Option Agreement has been duly executed by the parties hereto as of the Date of Grant.

RIO VISTA ENERGY PARTNERS L.P.

By: RIO VISTA GP LLC, general partner

By: /s/ Ian T. Bothwell
    -----------------------------------
        Ian T. Bothwell, Treasurer

-5-

ACCEPTED AND AGREED:

SHORE CAPITAL LLC

By: /s/ Richard Shore, Jr.
   ----------------------------------
        Richard Shore, Jr., President

-6-

NEITHER THIS WARRANT NOR THE SHARES ISSUABLE UPON EXERCISE
HEREOF HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF

1933, AS AMENDED (THE "ACT"), OR THE SECURITIES LAWS OF ANY
STATE. NEITHER THIS WARRANT NOR THE SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE HEREOF MAY BE SOLD OR OTHERWISE
TRANSFERRED IN THE ABSENCE OF REGISTRATION OR QUALIFICATION OR AN EXEMPTION THEREFROM UNDER APPLICABLE LAW.

COMMON STOCK PURCHASE WARRANT
Void after July 10, 2006

Warrant to Purchase 763,737 Shares
of Common Stock, $0.01 par value
of Penn Octane Corporation
Dated October 1, 2004

PENN OCTANE CORPORATION (POCC)

This is to Certify That, FOR VALUE RECEIVED,

Shore Capital, LLC, a California limited liability company,

or registered assign(s) (herein referred to as the "Holder") is entitled to purchase, subject to the provisions hereof, from PENN OCTANE CORPORATION, a Delaware corporation (the "Company"), but not later than 5:00 p.m., California time, on July 10, 2006 (or, if such date is not a Business Day in Palm Desert, California, then on the next succeeding day which shall be a Business Day), 763,737 shares of Common Stock, $0.01 par value, of the Company (the "Common Stock") at an exercise price of $1.14 per share, subject to adjustment as to number of shares and purchase price as set forth in Section 6 below. The exercise price of a share of Common Stock in effect at any time and as adjusted from time to time is hereinafter sometimes referred to as the "Exercise Price". For purposes of this Warrant, a "Business Day" shall mean any day other than a Saturday, a Sunday or a day on which banking institutions in New York, New York, or in Palm Desert, California, are authorized by law or regulation to close.

The shares of Common Stock issuable upon exercise of the Warrants are sometimes herein called the "Warrant Stock."


Common Stock Purchase Warrant

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1. Exercise of Warrant. This Warrant may be exercised in whole or in part at any time and from time to time, subject to the limitations as set forth in
Section 2, by presentation and surrender hereof to the Company at its principal office with the Purchase Form annexed hereto duly executed and accompanied by payment of the Exercise Price in immediately available funds for the number of shares specified in such form. If this Warrant is exercised in part only, the Company shall, upon surrender of this Warrant for cancellation, execute and deliver a new Warrant evidencing the right of the Holder to purchase the balance of the shares purchasable hereunder. Upon receipt by the Company of this Warrant at the office of the Company, in proper form for exercise, accompanied by payment of the Exercise Price, the Holder shall be deemed to be the holder of record of the shares of Common Stock issuable upon such exercise, notwithstanding that certificates representing such shares of Common Stock shall not then be actually delivered to the Holder. The issuance of certificates for shares of Common Stock upon the exercise of this Warrant shall be made without charge to the Holder for any issuance tax in respect thereof (with the exception of any federal or state income taxes applicable thereto), all such taxes to be paid by the Company, it being understood however that the Holder shall be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than that of the Holder. The Company will at no time close its transfer books against the transfer of this Warrant or the issuance of any shares of Common Stock issuable upon the exercise of this Warrant in any manner which interferes with the timely exercise of this Warrant.

2. Vesting Of Warrants. The Warrants shall be fully vested and exercisable as of October 1, 2004, provided that the Company has completed the distribution of common units of Rio Vista Energy Partners L.P. to the stockholders of the Company on or before September 30, 2004.

3. Reservation of Shares; Stock Fully Paid. The Company agrees that at all times there shall be authorized and reserved for issuance upon exercise of this Warrant such number of shares of its Common Stock as shall be required for issuance or delivery upon exercise of this Warrant. All shares which may be issued upon exercise hereof will, upon issuance, and receipt of payment therefor, be duly authorized, validly issued, fully paid and non-assessable.

4. Fractional Shares. This Warrant shall not be exercisable in such manner as to require the issuance of fractional shares. If, as a result of adjustment in the Exercise Price or the number of shares of Common Stock to be received upon exercise of this Warrant, fractional shares would be issuable, no such fractional shares shall be issued. In lieu thereof, the Company shall pay the Holder an amount in cash equal to such fraction multiplied by the Fair Market Value of a share of Common Stock. The term "Fair Market Value" shall mean, as of a particular date, the market price on such date.

For purposes of this Warrant, the market price on any day shall be the last sale price on such day on the NASDAQ Stock Market, or, if the Common Stock is not then listed or admitted to trading on the NASDAQ Stock Market, on such other principal stock exchange on which such stock is then listed or admitted to trading, or, if no sale takes place on such day on any such

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Common Stock Purchase Warrant

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exchange, the average of the closing bid and asked prices on such day as officially quoted on any such exchange, or, if the Common Stock is not then listed or admitted to trading on any stock exchange, the average of the reported closing bid and asked prices on such day in the over-the-counter market as quoted on the National Association of Securities Dealers Automated Quotation System or, if not so quoted, then as furnished by any member of the National Association of Securities Dealers, Inc. selected by the Company. If there shall be no meaningful over-the-counter market, then Fair Market Value shall be such amount, not less than book value, as may be determined by the Board of Directors of the Company.

5. Rights of the Holder. The Holder shall not, by virtue hereof, be entitled to any rights of a stockholder in the Company, either at law or in equity, and the rights of the Holder are limited to those expressed in this Warrant.

6. Adjustment of Exercise Price and Number of Shares. The number and kind of securities purchasable upon the exercise or exchange of this Warrant and the Exercise Price shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:

A. Adjustment for Change in Capital Stock. If at any time after the date hereof, the Company:

1. pays a dividend or makes a distribution on its Common Stock in shares of its Common Stock;

2. subdivides its outstanding shares of Common Stock into a greater number of shares;

3. combines its outstanding shares of Common Stock into a smaller number of shares;

4. makes a distribution on its Common Stock in shares of its capital stock other than Common Stock; or

5. issues by reclassification of its Common Stock any shares of its capital stock;

then the Exercise Price in effect immediately prior to such action shall be adjusted so that the Holder may receive, upon exercise or exchange of this Warrant and payment of the same aggregate consideration, the number of shares of capital stock of the Company which the Holder would have owned immediately following such action if the Holder had exercised or exchanged the Warrant immediately prior to such action.

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Common Stock Purchase Warrant

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The adjustment shall become effective immediately after the record date in the case of a dividend or distribution and immediately after the effective date in the case of a subdivision, combination or reclassification.

B. Adjustment for Other Distributions. If at any time after the date hereof, the Company distributes to all holders of its Common Stock any of its assets or debt securities, the Exercise Price following the record date shall be adjusted in accordance with the following formula:

E'= E x M-F

M

where:  E'     =  the adjusted Exercise Price.

        E      =  the Exercise Price immediately prior to the adjustment.

        M      =  the current market price (as defined in Section 4 above) per share of Common
                  Stock on the record date of the distribution.

        F      =  the aggregate fair market value (as conclusively determined by the Board of
                  Directors of the Company) on the record date of the assets or debt securities to be
                  distributed divided by the number of outstanding shares of Common Stock.

The adjustment shall be made successively whenever any such distribution is made and shall become effective immediately after the record date for the determination of shareholders entitled to receive the distribution. In the event that such distribution is not actually made, the Exercise Price shall again be adjusted to the Exercise Price as determined without giving effect to the calculation provided hereby. In no event shall the Exercise Price be adjusted to an amount less than zero.

In addition to the foregoing, the number of shares of capital stock of the Company which the holder is entitled to receive upon exercise of their Warrant shall be appropriately and equitably adjusted as determined by the Company's Board of Directors to make appropriate provision for any adjustments in the Exercise price made on account of the foregoing

This subsection does not apply to cash dividends or cash distributions paid out of consolidated current or retained earnings as shown on the books of the Company and paid in the ordinary course of business.

C. Deferral of Issuance or Payment. In any case in which an event covered by this Section 6 shall require that an adjustment in the Exercise Price be made effective as of a record date, the Company may elect to defer making such adjustment until the occurrence of such event.

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Common Stock Purchase Warrant

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If the Company so defers making any such adjustment and if this Warrant is exercised after such record date but before the occurrence of such event, the shares of Common Stock and other capital stock of the Company, if any, issuable upon such exercise, had such adjustment been made as of the record date, over and above the shares of Common Stock or other capital stock of the Company, if any, issuable upon such exercise on the basis of the Exercise Price as unadjusted, shall be issued promptly following the occurrence of such event and the Company shall pay to the Holder by check any amount in lieu of the issuance of fractional shares pursuant to Section 4.

D. When No Adjustment Required. No adjustment need be made for a change in the par value or no par value of the Common Stock.

E. Statement of Adjustments. Whenever the Exercise Price and number of shares of Common Stock purchasable hereunder is required to be adjusted as provided herein, the Company shall promptly prepare a certificate signed by its President or any Vice President and its Treasurer or Assistant Treasurer, setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated (including a description hereunder), and the Exercise Price and number of shares of Common Stock purchasable hereunder after giving effect to such adjustment, and shall promptly cause copies of such certificates to be mailed to the Holder.

F. No Adjustment Upon Exercise of Warrants. No adjustments shall be made under any Section herein in connection with the issuance of Warrant Stock upon exercise or exchange of the Warrants.

G. No adjustment for Small Amounts. Anything herein to the contrary notwithstanding, no adjustment of the Exercise Price shall be made if the amount of such adjustment shall be less than $0.05 per share, but in such case, any adjustment that would otherwise be required then to be made shall be carried forward and shall be made at the time and together with the next subsequent adjustment which, together with any adjustment so carried forward, shall amount to $.05 per share or more.

H. Common Stock Defined. Whenever reference is made in Section 6.A to the issue of shares of Common Stock, the term "Common Stock" shall include any equity securities of any class of the Company hereinafter authorized which shall not be limited to a fixed sum or percentage in respect of the right of the holders thereof to participate in dividends or distributions of assets upon the voluntary or involuntary liquidation, dissolution or winding up of the Company. Subject to the provisions of Section 8 hereof, however, shares issuable upon exercise or exchange hereof shall include only shares of the class designated as Common Stock of the Company as of the date hereof or shares of any class or classes resulting from any reclassification or reclassifications thereof or as a result of any corporate reorganization as provided for in Section 8 hereof.

-5-

Common Stock Purchase Warrant

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7. Notice to Warrant Holders. So long as this Warrant shall be outstanding,
(i) if the Company shall pay any dividend or make any distribution upon its Common Stock, or (ii) if the Company shall offer to the holders of Common Stock for subscription or purchase by them any shares of stock or securities of any class or any other rights, or (iii) if any capital reorganization of the Company, reclassification of the capital stock of the Company, consolidation or merger of the Company with or into another corporation, or any conveyance of all or substantially all of the assets of the Company, or voluntary or involuntary dissolution or liquidation of the Company shall be effected, then, in any such case, the Company shall cause to be mailed to the Holder, at least thirty (30) days prior to the date specified in (x) or (y) below, as the case may be, a notice containing a brief description of the proposed action and stating the date on which (x) a record is to be taken for the purpose of such dividend, distribution or rights, or (y) such reclassification, reorganization, consolidation, merger, conveyance, dissolution or liquidation is to take place and the date, if any is to be fixed, as of which the holders of Common Stock of record shall be entitled to exchange their shares of Common Stock for securities or other property deliverable upon such reclassification, reorganization, consolidation, merger, conveyance, dissolution or liquidation.

8. Reclassification, Reorganization, Consolidation or Merger. In the event of any reclassification, capital reorganization or other change of outstanding shares of Common Stock of the Company (other than a subdivision or combination of the outstanding Common Stock and other than a change in the par value of the Common Stock) or in the event of any consolidation or merger of the Company with or into another corporation (other than a merger in which merger the Company is the continuing corporation and that does not result in any reclassification, capital reorganization or other change of outstanding shares of Common Stock of the class issuable upon exercise or exchange of this Warrant) or in the event of any sale, lease, transfer or conveyance to another corporation of the property and assets of the Company as an entirety or substantially as an entirety, the Company shall, as a condition precedent to such transaction, cause effective provisions to be made so that the Holder shall have the right thereafter, by exercising this Warrant, to purchase the kind and amount of shares of stock and other securities and property (including cash) receivable upon such reclassification, capital reorganization and other change, consolidation, merger, sale or conveyance by a holder of the number of shares of Common Stock that might have been received upon exercise or exchange of this Warrant immediately prior to such reclassification, capital reorganization, change, consolidation, merger, sale or conveyance. Any such provision shall include provisions for adjustments in respect of such shares of stock and other securities and property that shall be as nearly equivalent as may be practicable to the adjustments provided for in this Warrant. The foregoing provisions of this Section 8 shall similarly apply to successive reclassifications, capital reorganizations and changes of shares of Common Stock and to successive consolidations, mergers, sales or conveyances. In the event that in connection with any such capital reorganization or classification, consolidation, merger, sale or conveyance, additional shares of Common Stock shall be issued in exchange, conversion, substitution or payment, in whole or in part, for, or of, a security of the Company other than Common Stock, any such issue shall be treated as an issue of Common Stock covered by the provisions of Section 6.A hereof.

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Common Stock Purchase Warrant

Page 7 of 8

9. Certain Obligations of the Company. The Company agrees that it will not increase the par value of the shares of Warrant Stock issuable upon exercise of this Warrant above the prevailing and currently applicable Exercise Price hereunder, and that before taking any action that would cause an adjustment reducing the prevailing and current applicable Exercise Price hereunder below the then par value of the Warrant Stock at the time issuable upon exercise of this Warrant, the Company will take such corporate action, as in the opinion of its counsel, may be necessary in order that the Company may validly issue fully paid, nonassessable shares of such Warrant Stock. The Company will maintain an office or agency (which shall initially be the Company's principal office in Redwood City, California) where presentations and demands to or upon the Company in respect of this Warrant may be made and will give notice in writing to the registered holders of the then outstanding Warrants, at their addresses as shown on the books of the Company, of each change of location thereof.

10. Determination by Board of Directors. All determinations by the Board of Directors of the Company under the provisions of this Warrant will be made in good faith with due regard to the interest of the Holder and in accordance with sound financial practices.

11. Notice. All notices to the Holder shall be in writing, and all notices and certificates given to the Holder shall be sent registered or certified mail, return receipt requested, to such Holder at his address appearing on the records of the Company.

12. Replacement of Lost, Stolen, Destroyed or Mutilated Warrants. Upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant and, in the case of any such loss, theft or destruction, upon delivery of any indemnity bond in such reasonable amount as the Company may determine in the case of any such mutilation, upon the surrender of such Warrant for cancellation, the Company at its expense, will execute and deliver, in lieu of such lost, stolen, destroyed or mutilated Warrant, a new Warrant of like tenor.

13. Number and Gender. Whenever the singular number is used herein, the same shall include the plural where appropriate, and words of any gender shall include each other gender where appropriate.

14. Applicable Law. This Warrant shall be governed by, and construed in accordance with, the laws of the State of California, without regard to its conflict of laws principles.

PENN OCTANE CORPORATION

By:/s/  Ian  T.  Bothwell
   ---------------------------------------
Name: Ian T. Bothwell
Title: Vice President, Chief  Financial
Officer

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Common Stock Purchase Warrant

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PURCHASE FORM

Dated __________ , ____

The undersigned hereby irrevocably elects to exercise the within Warrant to purchase ___________ shares of Common Stock and hereby makes payment of in payment of the exercise price thereof.

Signature______________________________

-8-

FIRST AMENDED AND RESTATED
AGREEMENT OF LIMITED PARTNERSHIP

OF

RIO VISTA ENERGY PARTNERS L.P.


                                    TABLE OF CONTENTS

                                                                                        Page
ARTICLE I     DEFINITIONS                                                                  1
     SECTION 1.1    Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . .    1
     SECTION 1.2    Construction. . . . . . . . . . . . . . . . . . . . . . . . . . . .   20
ARTICLE II    ORGANIZATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   20
     SECTION 2.1    Formation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   20
     SECTION 2.2    Name. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   20
     SECTION 2.3    Registered Office; Registered Agent; Principal Office; Other
                    Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   20
     SECTION 2.4    Purpose and Business  . . . . . . . . . . . . . . . . . . . . . . .   20
     SECTION 2.5    Powers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   21
     SECTION 2.6    Power of Attorney . . . . . . . . . . . . . . . . . . . . . . . . .   21
     SECTION 2.7    Term. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   23
     SECTION 2.8    Title to Partnership Assets . . . . . . . . . . . . . . . . . . . .   23
ARTICLE III   RIGHTS OF LIMITED PARTNERS  . . . . . . . . . . . . . . . . . . . . . . .   24
     SECTION 3.1    Limitation of Liability . . . . . . . . . . . . . . . . . . . . . .   24
     SECTION 3.2    Management of Business. . . . . . . . . . . . . . . . . . . . . . .   24
     SECTION 3.3    Outside Activities of the Limited Partners  . . . . . . . . . . . .   24
     SECTION 3.4    Rights of Limited Partners. . . . . . . . . . . . . . . . . . . . .   24
ARTICLE IV    CERTIFICATES; RECORD HOLDERS; TRANSFER OF PARTNERSHIP INTERESTS;
              REDEMPTION OF PARTNERSHIP INTERESTS . . . . . . . . . . . . . . . . . . .   25
     SECTION 4.1    Certificates. . . . . . . . . . . . . . . . . . . . . . . . . . . .   25
     SECTION 4.2    Mutilated, Destroyed, Lost or Stolen Certificates . . . . . . . . .   25
     SECTION 4.3    Record Holders. . . . . . . . . . . . . . . . . . . . . . . . . . .   26
     SECTION 4.4    Transfer Generally  . . . . . . . . . . . . . . . . . . . . . . . .   27
     SECTION 4.5    Registration and Transfer of Limited Partner Interests. . . . . . .   27
     SECTION 4.6    Transfer of the General Partner's General Partner Interest. . . . .   28
     SECTION 4.7    Transfer of Incentive Distribution Rights . . . . . . . . . . . . .   29
     SECTION 4.8    Restrictions on Transfers . . . . . . . . . . . . . . . . . . . . .   29
     SECTION 4.9    Citizenship Certificates; Non-citizen Assignees . . . . . . . . . .   30
     SECTION 4.10   Redemption of Partnership Interests of Non-citizen Assignees. . . .   31


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                                    TABLE OF CONTENTS
                                       (continued)
                                                                                        Page

ARTICLE V     CAPITAL CONTRIBUTIONS AND ISSUANCE OF PARTNERSHIP
              INTERESTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   32
     SECTION 5.1    Organizational Contributions. . . . . . . . . . . . . . . . . . . .   32
     SECTION 5.2    Contributions by the General Partner and its Affiliates . . . . . .   32
     SECTION 5.3    Contributions by Initial Limited Partners and Distributions to the
                    General Partner . . . . . . . . . . . . . . . . . . . . . . . . . .   32
     SECTION 5.4    Interest and Withdrawal . . . . . . . . . . . . . . . . . . . . . .   33
     SECTION 5.5    Capital Accounts. . . . . . . . . . . . . . . . . . . . . . . . . .   33
     SECTION 5.6    Issuances of Additional Partnership Securities. . . . . . . . . . .   36
     SECTION 5.7    Limitations on Issuance of Additional Partnership Securities. . . .   36
     SECTION 5.8    [Reserved]. . . . . . . . . . . . . . . . . . . . . . . . . . . . .   37
     SECTION 5.9    Limited Preemptive Right. . . . . . . . . . . . . . . . . . . . . .   37
     SECTION 5.10   Splits and Combinations . . . . . . . . . . . . . . . . . . . . . .   37
     SECTION 5.11   Fully Paid and Non-Assessable Nature of Limited Partner
                    Interests . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   38
ARTICLE VI    ALLOCATIONS AND DISTRIBUTIONS . . . . . . . . . . . . . . . . . . . . . .   38
     SECTION 6.1    Allocations for Capital Account Purposes. . . . . . . . . . . . . .   38
     SECTION 6.2    Allocations for Tax Purposes. . . . . . . . . . . . . . . . . . . .   45
     SECTION 6.3    Requirement and Characterization of Distributions; Distributions to
                    Record Holders. . . . . . . . . . . . . . . . . . . . . . . . . . .   47
     SECTION 6.4    Distributions of Available Cash from Operating Surplus. . . . . . .   48
     SECTION 6.5    Distributions of Available Cash from Capital Surplus. . . . . . . .   49
     SECTION 6.6    Adjustment of Minimum Quarterly Distribution and Target Distribution
                    Levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   49
     SECTION 6.7    [Reserved]  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   49
     SECTION 6.8    Special Provisions Relating to the Holders of Incentive Distribution
                    Rights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   49
     SECTION 6.9    Entity-Level Taxation . . . . . . . . . . . . . . . . . . . . . . .   50
ARTICLE VII   MANAGEMENT AND OPERATION OF BUSINESS  . . . . . . . . . . . . . . . . . .   50
     SECTION 7.1    Management. . . . . . . . . . . . . . . . . . . . . . . . . . . . .   50
     SECTION 7.2    Certificate of Limited Partnership. . . . . . . . . . . . . . . . .   52
     SECTION 7.3    Restrictions on the General Partner's Authority . . . . . . . . . .   53


                                      -ii-

                                    TABLE OF CONTENTS
                                       (continued)
                                                                                        Page

     SECTION 7.4    Reimbursement of the General Partner  . . . . . . . . . . . . . . .   53
     SECTION 7.5    Outside Activities. . . . . . . . . . . . . . . . . . . . . . . . .   54
     SECTION 7.6    Loans from the General Partner; Loans or Contributions from the
                    Partnership; Contracts with Affiliates; Certain Restrictions on the
                    General Partner . . . . . . . . . . . . . . . . . . . . . . . . . .   55
     SECTION 7.7    Indemnification . . . . . . . . . . . . . . . . . . . . . . . . . .   57
     SECTION 7.8    Liability of Indemnitees. . . . . . . . . . . . . . . . . . . . . .   59
     SECTION 7.9    Resolution of Conflicts of Interest . . . . . . . . . . . . . . . .   59
     SECTION 7.10   Other Matters Concerning the General Partner. . . . . . . . . . . .   61
     SECTION 7.11   Purchase or Sale of Partnership Securities. . . . . . . . . . . . .   62
     SECTION 7.12   Registration Rights of the General Partner and its Affiliates . . .   62
     SECTION 7.13   Reliance by Third Parties . . . . . . . . . . . . . . . . . . . . .   64
ARTICLE VIII  BOOKS, RECORDS, ACCOUNTING AND REPORTS. . . . . . . . . . . . . . . . . .   65
     SECTION 8.1    Records and Accounting. . . . . . . . . . . . . . . . . . . . . . .   65
     SECTION 8.2    Fiscal Year . . . . . . . . . . . . . . . . . . . . . . . . . . . .   65
     SECTION 8.3    Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   65
ARTICLE IX    TAX MATTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   65
     SECTION 9.1    Tax Returns and Information . . . . . . . . . . . . . . . . . . . .   65
     SECTION 9.2    Tax Elections . . . . . . . . . . . . . . . . . . . . . . . . . . .   66
     SECTION 9.3    Tax Controversies . . . . . . . . . . . . . . . . . . . . . . . . .   66
     SECTION 9.4    Withholding . . . . . . . . . . . . . . . . . . . . . . . . . . . .   66
ARTICLE X     ADMISSION OF PARTNERS . . . . . . . . . . . . . . . . . . . . . . . . . .   67
     SECTION 10.1   Admission of Initial Limited Partners . . . . . . . . . . . . . . .   67
     SECTION 10.2   Admission of Substituted Limited Partner. . . . . . . . . . . . . .   67
     SECTION 10.3   Admission of Successor General Partner. . . . . . . . . . . . . . .   67
     SECTION 10.4   Admission of Additional Limited Partners. . . . . . . . . . . . . .   68
     SECTION 10.5   Amendment of Agreement and Certificate of Limited Partnership . . .   68
ARTICLE XI    WITHDRAWAL OR REMOVAL OF PARTNERS . . . . . . . . . . . . . . . . . . . .   68
     SECTION 11.1   Withdrawal of the General Partner . . . . . . . . . . . . . . . . .   68
     SECTION 11.2   Removal of the General Partner. . . . . . . . . . . . . . . . . . .   70


                                      -iii-

                                    TABLE OF CONTENTS
                                       (continued)
                                                                                        Page

     SECTION 11.3   Interest of Departing Partner and Successor General Partner . . . .   71
     SECTION 11.4   Withdrawal of Limited Partners. . . . . . . . . . . . . . . . . . .   72
ARTICLE XII   DISSOLUTION AND LIQUIDATION . . . . . . . . . . . . . . . . . . . . . . .   72
     SECTION 12.1   Dissolution . . . . . . . . . . . . . . . . . . . . . . . . . . . .   72
     SECTION 12.2   Continuation of the Business of the Partnership After
                    Dissolution . . . . . . . . . . . . . . . . . . . . . . . . . . . .   73
     SECTION 12.3   Liquidator. . . . . . . . . . . . . . . . . . . . . . . . . . . . .   73
     SECTION 12.4   Liquidation . . . . . . . . . . . . . . . . . . . . . . . . . . . .   74
     SECTION 12.5   Cancellation of Certificate of Limited Partnership  . . . . . . . .   75
     SECTION 12.6   Return of Contributions . . . . . . . . . . . . . . . . . . . . . .   75
     SECTION 12.7   Waiver of Partition . . . . . . . . . . . . . . . . . . . . . . . .   75
     SECTION 12.8   Capital Account Restoration . . . . . . . . . . . . . . . . . . . .   75
ARTICLE XIII  AMENDMENT OF PARTNERSHIP AGREEMENT; MEETINGS;
              RECORD DATE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   75
     SECTION 13.1   Amendment to be Adopted Solely by the General Partner . . . . . . .   75
     SECTION 13.2   Amendment Procedures. . . . . . . . . . . . . . . . . . . . . . . .   77
     SECTION 13.3   Amendment Requirements  . . . . . . . . . . . . . . . . . . . . . .   78
     SECTION 13.4   Special Meetings. . . . . . . . . . . . . . . . . . . . . . . . . .   78
     SECTION 13.5   Notice of a Meeting . . . . . . . . . . . . . . . . . . . . . . . .   79
     SECTION 13.6   Record Date . . . . . . . . . . . . . . . . . . . . . . . . . . . .   79
     SECTION 13.7   Adjournment . . . . . . . . . . . . . . . . . . . . . . . . . . . .   79
     SECTION 13.8   Waiver of Notice; Approval of Meeting; Approval of Minutes  . . . .   79
     SECTION 13.9   Quorum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   80
     SECTION 13.10  Conduct of a Meeting. . . . . . . . . . . . . . . . . . . . . . . .   80
     SECTION 13.11  Action Without a Meeting. . . . . . . . . . . . . . . . . . . . . .   80
     SECTION 13.12  Voting and Other Rights . . . . . . . . . . . . . . . . . . . . . .   81
ARTICLE XIV   MERGER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   82
     SECTION 14.1   Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   82
     SECTION 14.2   Procedure for Merger or Consolidation . . . . . . . . . . . . . . .   82
     SECTION 14.3   Approval by Limited Partners of Merger or Consolidation. . . . . . .  83
     SECTION 14.4   Certificate of Merger . . . . . . . . . . . . . . . . . . . . . . .   84


                                      -iv-

                                    TABLE OF CONTENTS
                                       (continued)
                                                                                        Page

     SECTION 14.5   Effect of Merger. . . . . . . . . . . . . . . . . . . . . . . . . .   84
ARTICLE XV    GENERAL PROVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .   84
     SECTION 15.1   Addresses and Notices . . . . . . . . . . . . . . . . . . . . . . .   84
     SECTION 15.2   Further Action. . . . . . . . . . . . . . . . . . . . . . . . . . .   85
     SECTION 15.3   Binding Effect. . . . . . . . . . . . . . . . . . . . . . . . . . .   85
     SECTION 15.4   Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . .   85
     SECTION 15.5   Creditors . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   85
     SECTION 15.6   Waiver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .   85
     SECTION 15.7   Counterparts. . . . . . . . . . . . . . . . . . . . . . . . . . . .   85
     SECTION 15.8   Applicable Law  . . . . . . . . . . . . . . . . . . . . . . . . . .   86
     SECTION 15.9   Invalidity of Provisions. . . . . . . . . . . . . . . . . . . . . .   86
     SECTION 15.10  Consent of Partners . . . . . . . . . . . . . . . . . . . . . . . .   86

-v-

FIRST AMENDED AND RESTATED
AGREEMENT OF LIMITED PARTNERSHIP OF
RIO VISTA ENERGY PARTNERS L.P.

THIS FIRST AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP OF RIO VISTA ENERGY PARTNERS L.P., dated as of September 16, 2004, is entered into by and among Rio Vista GP LLC, a Delaware limited liability company, as the General Partner, and Penn Octane Corporation, a Delaware corporation, as the Organizational Limited Partner, together with any other Persons who become Partners in the Partnership or parties hereto as provided herein. In consideration of the covenants, conditions and agreements contained herein, the parties hereto hereby agree as follows:

ARTICLE I

DEFINITIONS

SECTION 1.1 Definitions. The following definitions shall be for all purposes, unless otherwise clearly indicated to the contrary, applied to the terms used in this Agreement.

"Acquisition" means any transaction in which any Group Member acquires (through an asset acquisition, merger, stock acquisition or other form of investment) control over all or a portion of the assets, properties or business of another Person for the purpose of increasing the operating capacity or revenues of the Partnership Group from the operating capacity or revenues of the Partnership Group existing immediately prior to such transaction.

"Additional Book Basis" means the portion of any remaining Carrying Value of an Adjusted Property that is attributable to positive adjustments made to such Carrying Value as a result of Book-Up Events. For purposes of determining the extent that Carrying Value constitutes Additional Book Basis:

(a) Any negative adjustment made to the Carrying Value of an Adjusted Property as a result of either a Book-Down Event or a Book-Up Event shall first be deemed to offset or decrease that portion of the Carrying Value of such Adjusted Property that is attributable to any prior positive adjustments made thereto pursuant to a Book-Up Event or Book-Down Event.

(b) If Carrying Value that constitutes Additional Book Basis is reduced as a result of a Book-Down Event and the Carrying Value of other property is increased as a result of such Book-Down Event, an allocable portion of any such increase in Carrying Value shall be treated as Additional Book Basis; provided that the amount treated as Additional Book Basis pursuant hereto as a result of such Book-Down Event shall not exceed the amount by which the Aggregate Remaining Net Positive Adjustments after such Book-Down Event exceeds the remaining Additional Book Basis attributable to all of the Partnership's Adjusted Property after such Book-Down Event (determined without regard to the application of this clause (b) to such Book-Down Event).

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"Additional Book Basis Derivative Items" means any Book Basis Derivative Items that are computed with reference to Additional Book Basis. To the extent that the Additional Book Basis attributable to all of the Partnership's Adjusted Property as of the beginning of any taxable period exceeds the Aggregate Remaining Net Positive Adjustments as of the beginning of such period (the "Excess Additional Book Basis"), the Additional Book Basis Derivative Items for such period shall be reduced by the amount that bears the same ratio to the amount of Additional Book Basis Derivative Items determined without regard to this sentence as the Excess Additional Book Basis bears to the Additional Book Basis as of the beginning of such period.

"Additional Limited Partner" means a Person admitted to the Partnership as a Limited Partner pursuant to Section 10.4 and who is shown as such on the books and records of the Partnership.

"Adjusted Capital Account" means the Capital Account maintained for each Partner as of the end of each fiscal year of the Partnership, (a) increased by any amounts that such Partner is obligated to restore under the standards set by Treasury Regulation Section 1.704-1(b)(2)(ii)(c) (or is deemed obligated to restore under Treasury Regulation Sections 1.704-2(g) and 1.704-2(i)(5)) and (b) decreased by (i) the amount of all losses and deductions that, as of the end of such fiscal year, are reasonably expected to be allocated to such Partner in subsequent years under Sections 704(e)(2) and 706(d) of the Code and Treasury Regulation Section 1.751-1(b)(2)(ii), and (ii) the amount of all distributions that, as of the end of such fiscal year, are reasonably expected to be made to such Partner in subsequent years in accordance with the terms of this Agreement or otherwise to the extent they exceed offsetting increases to such Partner's Capital Account that are reasonably expected to occur during (or prior to) the year in which such distributions are reasonably expected to be made (other than increases as a result of a minimum gain chargeback pursuant to Section 6.1(d)(i) or 6.1(d)(ii)). The foregoing definition of Adjusted Capital Account is intended to comply with the provisions of Treasury Regulation Section 1.704-1(b)(2)(ii)(d) and shall be interpreted consistently therewith. The "Adjusted Capital Account" of a Partner in respect of a General Partner Interest, a Common Unit or an Incentive Distribution Right or any other specified interest in the Partnership shall be the amount which such Adjusted Capital Account would be if such General Partner Interest, Common Unit, Incentive Distribution Right or other interest in the Partnership were the only interest in the Partnership held by such Partner from and after the date on which such General Partner Interest, Common Unit, Incentive Distribution Right or other interest was first issued.

"Adjusted Operating Surplus" means, with respect to any period, Operating Surplus generated during such period (a) less (i) any net increase in Working Capital Borrowings with respect to such period and (ii) any net reduction in cash reserves for Operating Expenditures with respect to such period not relating to an Operating Expenditure made during such period, and (b) plus (i) any net decrease in Working Capital Borrowings with respect to such period, and
(ii) any net increase in cash reserves for Operating Expenditures with respect to such period required by any debt instrument for the repayment of principal, interest or premium. Adjusted Operating Surplus does not include that portion of Operating Surplus included in clause (a)(i) of the definition of Operating Surplus.

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"Adjusted Property" means any property the Carrying Value of which has been adjusted pursuant to Section 5.5(d)(i) or 5.5(d)(ii).

"Affiliate" means, with respect to any Person, any other Person that directly or indirectly through one or more intermediaries controls, is controlled by or is under common control with, the Person in question. As used herein, the term "control" means the possession, direct or indirect, of the power to direct or cause the direction of the management and policies of a Person, whether through ownership of voting securities, by contract or otherwise.

"Aggregate Remaining Net Positive Adjustments" means, as of the end of any taxable period, the sum of the Remaining Net Positive Adjustments of all the Partners.

"Agreed Allocation" means any allocation, other than a Required Allocation, of an item of income, gain, loss or deduction pursuant to the provisions of
Section 6.1, including, without limitation, a Curative Allocation (if appropriate to the context in which the term "Agreed Allocation" is used).

"Agreed Value" of any Contributed Property means the fair market value of such property or other consideration at the time of contribution as determined by the General Partner using such reasonable method of valuation as it may adopt. The General Partner shall, in its discretion, use such method as it deems reasonable and appropriate to allocate the aggregate Agreed Value of Contributed Properties contributed to the Partnership in a single or integrated transaction among each separate property on a basis proportional to the fair market value of each Contributed Property. With respect to the Contributed Property deemed contributed to the Partnership by an Initial Limited Partner (as described in the definition of Contributed Property), the Agreed Value shall be the value assigned for federal income tax purposes by the General Partner (in its reasonable discretion) to such Contributed Property.

"Agreement" means this First Amended and Restated Agreement of Limited Partnership of Rio Vista Energy Partners L.P., as it may be amended, supplemented or restated from time to time.

"Assignee" means a Non-citizen Assignee or a Person to whom one or more Limited Partner Interests have been transferred in a manner permitted under this Agreement and who has executed and delivered a Transfer Application as required by this Agreement, but who has not been admitted as a Substituted Limited Partner.

"Associate" means, when used to indicate a relationship with any Person,
(a) any corporation or organization of which such Person is a director, officer or partner or is, directly or indirectly, the owner of 20% or more of any class of voting stock or other voting interest; (b) any trust or other estate in which such Person has at least a 20% beneficial interest or as to which such Person serves as trustee or in a similar fiduciary capacity; and (c) any relative or spouse of such Person, or any relative of such spouse, who has the same principal residence as such Person.

"Available Cash" means, with respect to any Quarter ending prior to the Liquidation Date:

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(a) the sum of (i) all cash and cash equivalents of the Partnership Group on hand at the end of such Quarter, and (ii) all additional cash and cash equivalents of the Partnership Group on hand on the date of determination of Available Cash with respect to such Quarter resulting from Working Capital Borrowings made subsequent to the end of such Quarter, less

(b) the amount of any cash reserves that are necessary or appropriate in the reasonable discretion of the General Partner to (i) provide for the proper conduct of the business of the Partnership Group (including reserves for future capital expenditures and for anticipated future credit needs of the Partnership Group) subsequent to such Quarter,
(ii) comply with applicable law or any loan agreement, security agreement, mortgage, debt instrument or other agreement or obligation to which any Group Member is a party or by which it is bound or its assets are subject or (iii) provide funds for distributions under
Section 6.4 or 6.5 in respect of any one or more of the next four Quarters; provided, however, that the General Partner may not establish cash reserves pursuant to (iii) above if the effect of such reserves would be that the Partnership is unable to distribute the Minimum Quarterly Distribution on all Common Units, plus any Cumulative Common Unit Arrearage on all Common Units, with respect to such Quarter; and, provided further, that disbursements made by a Group Member or cash reserves established, increased or reduced after the end of such Quarter but on or before the date of determination of Available Cash with respect to such Quarter shall be deemed to have been made, established, increased or reduced, for purposes of determining Available Cash, within such Quarter if the General Partner so determines.

Notwithstanding the foregoing, "Available Cash" with respect to the Quarter in which the Liquidation Date occurs and any subsequent Quarter shall equal zero.

"Book Basis Derivative Items" means any item of income, deduction, gain or loss included in the determination of Net Income or Net Loss that is computed with reference to the Carrying Value of an Adjusted Property (e.g., depreciation, depletion, or gain or loss with respect to an Adjusted Property).

"Book-Down Event" means an event which triggers a negative adjustment to the Capital Accounts of the Partners pursuant to Section 5.5(d).

"Book-Tax Disparity" means with respect to any item of Contributed Property or Adjusted Property, as of the date of any determination, the difference between the Carrying Value of such Contributed Property or Adjusted Property and the adjusted basis thereof for federal income tax purposes as of such date. A Partner's share of the Partnership's Book-Tax Disparities in all of its Contributed Property and Adjusted Property will be reflected by the difference between such Partner's Capital Account balance as maintained pursuant to Section 5.5 and the hypothetical balance of such Partner's Capital Account computed as if it had been maintained strictly in accordance with federal income tax accounting principles.

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"Book-Up Event" means an event which triggers a positive adjustment to the Capital Accounts of the Partners pursuant to Section 5.5(d).

"Business" has the meaning assigned to such term in the Omnibus Agreement.

"Business Day" means Monday through Friday of each week, except that a legal holiday recognized as such by the government of the United States of America or the State of Texas shall not be regarded as a Business Day.

"Capital Account" means the capital account maintained for a Partner pursuant to Section 5.5. The "Capital Account" of a Partner in respect of a General Partner Interest, a Common Unit, an Incentive Distribution Right or any other Partnership Interest shall be the amount which such Capital Account would be if such General Partner Interest, Common Unit, Distribution Right or other Partnership Interest were the only interest in the Partnership held by such Partner from and after the date on which such General Partner Interest, Common Unit, Incentive Distribution Right or other Partnership Interest was first issued.

"Capital Contribution" means any cash, cash equivalents or the Net Agreed Value of Contributed Property that a Partner contributes to the Partnership pursuant to this Agreement or the Contribution Agreement.

"Capital Improvement" means any (a) addition or improvement to the capital assets owned by any Group Member or (b) acquisition of existing, or the construction of new, capital assets (including, without limitation, LPG transportation, storage facilities and logistics assets, and related assets), in each case if such addition, improvement, acquisition or construction is made to increase the operating capacity or revenues of the Partnership Group from the operating capacity or revenues of the Partnership Group existing immediately prior to such addition, improvement, acquisition or construction.

"Capital Surplus" has the meaning assigned to such term in Section 6.3(a).

"Carrying Value" means (a) with respect to a Contributed Property, the Agreed Value of such property reduced (but not below zero) by all depreciation, amortization and cost recovery deductions charged to the Partners' and Assignees' Capital Accounts in respect of such Contributed Property, and (b) with respect to any other Partnership property, the adjusted basis of such property for federal income tax purposes, all as of the time of determination. The Carrying Value of any property shall be adjusted from time to time in accordance with Sections 5.5(d)(i) and 5.5(d)(ii) and to reflect changes, additions or other adjustments to the Carrying Value for dispositions and acquisitions of Partnership properties, as deemed appropriate by the General Partner.

"Cause" means a court of competent jurisdiction has entered a final, non-appealable judgment finding the General Partner liable for actual fraud, gross negligence or willful or wanton misconduct in its capacity as a general partner of the Partnership.

"Certificate" means a certificate (i) substantially in the form of Exhibit A to this Agreement, (ii) issued in global form in accordance with the rules and regulations of the

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Depositary or (iii) in such other form as may be adopted by the General Partner in its discretion, issued by the Partnership evidencing ownership of one or more Common Units or a certificate, in such form as may be adopted by the General Partner in its discretion, issued by the Partnership evidencing ownership of one or more other Partnership Securities.

"Certificate of Limited Partnership" means the Certificate of Limited Partnership of the Partnership filed with the Secretary of State of the State of Delaware as such Certificate of Limited Partnership may be amended, supplemented or restated from time to time.

"Citizenship Certification" means a properly completed certificate in such form as may be specified by the General Partner by which a Limited Partner or an Assignee certifies that he (and if he is a nominee holding for the account of another Person, that to the best of his knowledge such other Person) is an Eligible Citizen.

"Claim" has the meaning assigned to such term in Section 7.12(c).

"Closing Date" means the date of the Distribution.

"Closing Price" means the last sale price on such day, regular way, or in case no such sale takes place on such day, the average of the closing bid and asked prices on such day, regular way, in either case as reported in the principal consolidated transaction reporting system with respect to securities listed or admitted for trading on the principal National Securities Exchange (other than the Nasdaq Stock Market) on which such Limited Partner Interests of such class are listed or admitted to trading or, if such Limited Partner Interests of such class are not listed or admitted to trading on any National Securities Exchange (other than the Nasdaq Stock Market), the last quoted price on such day or, if not so quoted, the average of the high bid and low asked prices on such day in the over-the-counter market, as reported by the Nasdaq Stock Market or such other system then in use, or, if on any such day such Limited Partner Interests of such class are not quoted by any such organization, the average of the closing bid and asked prices on such day as furnished by a professional market maker making a market in such Limited Partner Interests of such class selected by the General Partner, or if on any such day no market maker is making a market in such Limited Partner Interests of such class, the fair value of such Limited Partner Interests on such day as determined reasonably and in good faith by the General Partner.

"Code" means the Internal Revenue Code of 1986, as amended and in effect from time to time. Any reference herein to a specific section or sections of the Code shall be deemed to include a reference to any corresponding provision of any successor law.

"Combined Interest" has the meaning assigned to such term in Section 11.3(a).

"Commission" means the United States Securities and Exchange Commission.

"Common Unit" means a Partnership Security representing a fractional part of the Partnership Interests of all Limited Partners and Assignees and of the General Partner, and having the rights and obligations specified with respect to Common Units in this Agreement.

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"Common Unit Arrearage" means, with respect to any Common Unit, whenever issued, the excess, if any, of (a) the Minimum Quarterly Distribution with respect to a Common Unit in respect of such Quarter over (b) the sum of all Available Cash distributed with respect to a Common Unit in respect of such Quarter pursuant to Section 6.4(a)(i).

"Conflicts Committee" means a committee of the Board of Managers of the General Partner composed entirely of three or more managers who are not (a) security holders, officers or employees of the General Partner, (b) officers, directors or employees of any Affiliate of the General Partner or (c) holders of any ownership interest in the Partnership Group other than Common Units and who also meet the independence standards required to serve on an audit committee of a board of directors by the National Securities Exchange on which the Common Units are listed for trading.

"Contributed Property" means each property or other asset, in such form as may be permitted by the Delaware Act, but excluding cash, contributed to the Partnership. Once the Carrying Value of a Contributed Property is adjusted pursuant to Section 5.5(d), such property shall no longer constitute a Contributed Property, but shall be deemed an Adjusted Property. For purposes of this definition, each Limited Partner who receives Initial Common Units in the Distribution shall be treated as having received a distribution of an undivided interest in the assets contributed pursuant to the Contribution Agreement by Penn Octane Corporation to the Partnership, subject to applicable liabilities described in the Contribution Agreement, followed immediately thereafter by a contribution of the Partner's undivided interest in such assets subject to applicable liabilities, to the Partnership in exchange for the Partner's Initial Common Units received in the Distribution. For this purpose, each Limited Partner's undivided interest in the assets expressed as a percentage shall be the same percentage as the Limited Partner's Percentage Interest determined immediately following the Distribution.

"Contribution Agreement" means that certain Contribution, Conveyance and Assumption Agreement, dated as of September 16, 2004, among the General Partner, the Partnership, the Operating Partnership, Penn Octane Corporation and certain other Affiliates of Penn Octane Corporation, together with the additional conveyance documents and instruments contemplated or referenced thereunder.

"Controlled Person" means any corporation or partnership of which the Partnership or any Subsidiary owns or controls an interest in excess of 25%.

"Cumulative Common Unit Arrearage" means, with respect to any Common Unit, whenever issued, and as of the end of any Quarter, the excess, if any, of (a) the sum resulting from adding together the Common Unit Arrearage as to an Initial Common Unit for each Quarter ending on or before the last day of such Quarter over (b) the sum of any distributions theretofore made pursuant to
Section 6.4(a)(ii) and the second sentence of Section 6.5 with respect to an Initial Common Unit (including any distributions to be made in respect of the last of such Quarters).

"Curative Allocation" means any allocation of an item of income, gain, deduction, loss or credit pursuant to the provisions of Section 6.1(d)(x).

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"Current Market Price" as of any date of any class of Limited Partner Interests means the average of the daily Closing Prices per Limited Partner Interest of such class for the 20 consecutive Trading Days immediately prior to such date.

"Delaware Act" means the Delaware Revised Uniform Limited Partnership Act, 6 Del. C. Section 17-101, et seq., as amended, supplemented or restated from time to time, and any successor to such statute.

"Departing Partner" means a former General Partner from and after the effective date of any withdrawal or removal of such former General Partner pursuant to Section 11.1 or 11.2.

"Depositary" means, with respect to any Units issued in global form, The Depository Trust Company and its successors and permitted assigns.

"Distribution" means the pro rata distribution by Penn Octane Corporation of its 98% Limited Partner Interest representing 98% of the Common Units to the stockholders of Penn Octane Corporation, as described in the Registration Statement.

"Economic Risk of Loss" has the meaning set forth in Treasury Regulation
Section 1.752-2(a).

"Eligible Citizen" means a Person who is (i) qualified to own interests in real property in jurisdictions in which any Group Member does business or proposes to do business from time to time, and whose status as a Limited Partner or Assignee does not or would not subject such Group Member to a significant risk of cancellation or forfeiture of any of its properties or any interest therein and (ii) is not a Non-citizen.

"Event of Withdrawal" has the meaning assigned to such term in Section 11.1(a).

"First Liquidation Target Amount" has the meaning assigned to such term in
Section 6.1(c)(i)(C).

"First Target Distribution" means $0.292 per Unit per Quarter (or, with respect to the period commencing on the Closing Date and ending on the last day of the calendar quarter that includes the Closing Date, it means the product of $0.292 multiplied by a fraction of which the numerator is the number of days in such period, and of which the denominator is 91), subject to adjustment in accordance with Sections 6.6 and 6.9.

"Fully Diluted Basis" means, when calculating the number of Outstanding Units for any period, a basis that includes, in addition to the Outstanding Units, all Partnership Securities and options, rights, warrants and appreciation rights relating to an equity interest in the Partnership (a) that are convertible into or exercisable or exchangeable for Units that are senior to or pari passu with the Common Units, (b) whose conversion, exercise or exchange price is less than the Current Market Price on the date of such calculation, (c) that may be converted into or exercised or exchanged for such Units prior to or during the Quarter following the end of the last Quarter contained in the period for which the calculation is being made without the satisfaction of any contingency beyond the control of the holder other than the payment of consideration and the

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compliance with administrative mechanics applicable to such conversion, exercise or exchange, and (d) were not converted into or exercised or exchanged for such Units prior to the end of the last quarter referred to in clause (c) above.

"General Partner" means Rio Vista GP LLC and its successors and permitted assigns as general partner of the Partnership.

"General Partner Interest" means the ownership interest of the General Partner in the Partnership (in its capacity as a general partner without reference to any Limited Partner Interest held by it) which may be evidenced by Partnership Securities or a combination thereof or interest therein, and includes any and all benefits to which the General Partner is entitled as provided in this Agreement, together with all obligations of the General Partner to comply with the terms and provisions of this Agreement.

"Group" means a Person that with or through any of its Affiliates or Associates has any agreement, arrangement or understanding for the purpose of acquiring, holding, voting (except voting pursuant to a revocable proxy or consent given to such Person in response to a proxy or consent solicitation made to 10 or more Persons) or disposing of any Partnership Securities with any other Person that beneficially owns, or whose Affiliates or Associates beneficially own, directly or indirectly, Partnership Securities.

"Group Member" means a member of the Partnership Group.

"Holder" as used in Section 7.12, has the meaning assigned to such term in
Section 7.12(a).

"Incentive Distribution Right" means a non-voting Limited Partner Interest issued to the General Partner in exchange for the conveyance by the General Partner of $1,000 to the Partnership pursuant to Section 5.2, which Partnership Interest will confer upon the holder thereof only the rights and obligations specifically provided in this Agreement with respect to Incentive Distribution Rights (and no other rights otherwise available to or other obligations of a holder of a Partnership Interest). Notwithstanding anything in this Agreement to the contrary, the holder of an Incentive Distribution Right shall not be entitled to vote such Incentive Distribution Right on any Partnership matter except as may otherwise be required by law.

"Incentive Distributions" means any amount of cash distributed to the holders of the Incentive Distribution Rights pursuant to Sections 6.4(a)(iv),
(v), and (vi).

"Indemnified Persons" has the meaning assigned to such term in Section 7.12(c).

"Indemnitee" means (a) the General Partner, (b) any Departing Partner, (c) any Person who is or was an Affiliate of the General Partner or any Departing Partner, (d) any Person who is or was a member, partner, officer, director, employee, manager, agent or trustee of any Group Member, the General Partner or any Departing Partner or any Affiliate of any Group Member, the General Partner or any Departing Partner, and (e) any Person who is or was serving at the request of the General Partner or any Departing Partner or any Affiliate of the General Partner or any Departing Partner as an officer, director, employee, member, manager, partner, agent,

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fiduciary or trustee of another Person; provided, that a Person shall not be an Indemnitee by reason of providing, on a fee-for-services basis, trustee, fiduciary or custodial services.

"Initial Common Units" means the Common Units distributed in the Distribution.

"Initial Limited Partners" means the General Partner and the stockholders of Penn Octane Corporation that receive Initial Common Units in the Distribution, in each case upon being admitted to the Partnership in accordance with Section 10.1.

"Initial Unit Capital Account" means (a) with respect to each Initial Limited Partner, the value assigned for federal income tax purposes by the General Partner (in its reasonable discretion) to the Contributed Property contributed by an Initial Limited Partner to the Partnership (as described in the definition of Contributed Property) in exchange for the Initial Common Units, reduced by the amount of liabilities to which such property is subject as determined by the General Partner in its reasonable discretion or (b) with respect to any other class or series of Units, the price per Unit at which such class or series of Units is initially sold by the Partnership, as determined by the General Partner, in each case adjusted as the General Partner determines to be appropriate to give effect to any distribution, subdivision or combination of Units.

"Interim Capital Transactions" means the following transactions if they occur prior to the Liquidation Date: (a) borrowings, refinancings or refundings of indebtedness and sales of debt securities (other than Working Capital Borrowings and other than for items purchased on open account in the ordinary course of business) by any Group Member; (b) sales of equity interests by any Group Member; and (c) sales or other voluntary or involuntary dispositions of any assets of any Group Member other than (i) sales or other dispositions of inventory, accounts receivable and other assets in the ordinary course of business, and (ii) sales or other dispositions of assets as part of normal retirements or replacements.

"Issue Price" means the price at which a Unit is purchased from the Partnership, after taking into account any sales commission or underwriting discount charged to the Partnership.

"Limited Partner" means, unless the context otherwise requires, (a) the Organizational Limited Partner prior to the Distribution, each Initial Limited Partner, each Substituted Limited Partner, each Additional Limited Partner and any Departing Partner upon the change of its status from General Partner to Limited Partner pursuant to Section 11.3 or (b) solely for purposes of Articles V, VI, VII and IX, each Assignee; provided, however, that when the term "Limited Partner" is used herein in the context of any vote or other approval, including without limitation Articles XIII and XIV, such term shall not, solely for such purpose, include any holder of an Incentive Distribution Right except as may otherwise be required by law.

"Limited Partner Interest" means the ownership interest of a Limited Partner or Assignee in the Partnership, which may be evidenced by Common Units, Incentive Distribution Rights or other Partnership Securities or a combination thereof or interest therein, and includes any and all benefits to which such Limited Partner or Assignee is entitled as provided in this Agreement, together with all obligations of such Limited Partner or Assignee to comply with the terms and

10

provisions of this Agreement; provided, however, that when the term "Limited Partner Interest" is used herein in the context of any vote or other approval, including without limitation Articles XIII and XIV, such term shall not, solely for such purpose, include any holder of an Incentive Distribution Right except as may otherwise be required by law.

"Liquidation Date" means (a) in the case of an event giving rise to the dissolution of the Partnership of the type described in clauses (a) and (b) of the first sentence of Section 12.2, the date on which the applicable time period during which the holders of Outstanding Units have the right to elect to reconstitute the Partnership and continue its business has expired without such an election being made, and (b) in the case of any other event giving rise to the dissolution of the Partnership, the date on which such event occurs.

"Liquidator" means one or more Persons selected by the General Partner to perform the functions described in Section 12.3 as liquidating trustee of the Partnership within the meaning of the Delaware Act.

"Minimum Quarterly Distribution" means $0.25 per Unit per Quarter (or with respect to the period commencing on the Closing Date and ending on the last day of the calendar quarter that includes the Closing Date, it means the product of $0.25 multiplied by a fraction of which the numerator is the number of days in such period and of which the denominator is 91), subject to adjustment in accordance with Sections 6.6 and 6.9.

"National Securities Exchange" means an exchange registered with the Commission under Section 6(a) of the Securities Exchange Act of 1934, as amended, supplemented or restated from time to time, and any successor to such statute, or the Nasdaq Stock Market or any successor thereto.

"Net Agreed Value" means, (a) in the case of any Contributed Property, the Agreed Value of such property reduced by any liabilities either assumed by the Partnership upon such contribution or to which such property is subject when contributed, and (b) in the case of any property distributed to a Partner or Assignee by the Partnership, the Partnership's Carrying Value of such property (as adjusted pursuant to Section 5.5(d)(ii)) at the time such property is distributed, reduced by any indebtedness either assumed by such Partner or Assignee upon such distribution or to which such property is subject at the time of distribution, in either case, as determined under Section 752 of the Code.

"Net Income" means, for any taxable year, the excess, if any, of the Partnership's items of income and gain (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year over the Partnership's items of loss and deduction (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year. The items included in the calculation of Net Income shall be determined in accordance with Section 5.5(b) and shall not include any items specially allocated under Section 6.1(d); provided that the determination of the items that have been specially allocated under Section 6.1(d) shall be made as if Section 6.1(d)(xi) were not in this Agreement.

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"Net Loss" means, for any taxable year, the excess, if any, of the Partnership's items of loss and deduction (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year over the Partnership's items of income and gain (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year. The items included in the calculation of Net Loss shall be determined in accordance with Section 5.5(b) and shall not include any items specially allocated under Section 6.1(d); provided that the determination of the items that have been specially allocated under Section 6.1(d) shall be made as if Section 6.1(d)(xi) were not in this Agreement.

"Net Positive Adjustments" means, with respect to any Partner, the excess, if any, of the total positive adjustments over the total negative adjustments made to the Capital Account of such Partner pursuant to Book-Up Events and Book-Down Events.

"Net Termination Gain" means, for any taxable year, the sum, if positive, of all items of income, gain, loss or deduction recognized by the Partnership after the Liquidation Date. The items included in the determination of Net Termination Gain shall be determined in accordance with Section 5.5(b) and shall not include any items of income, gain or loss specially allocated under Section 6.1(d).

"Net Termination Loss" means, for any taxable year, the sum, if negative, of all items of income, gain, loss or deduction recognized by the Partnership after the Liquidation Date. The items included in the determination of Net Termination Loss shall be determined in accordance with Section 5.5(b) and shall not include any items of income, gain or loss specially allocated under Section 6.1(d).

"Non-citizen" means (1) any person (including any individual, a partnership, a corporation or an association) who is not a United States citizen, within the meaning of Section 2 of the Shipping Act, 1916, as amended or as it may hereafter be amended; (2) any foreign government or representative thereof; (3) any corporation, the president, chief executive officer or chairman of the board of directors of which is a Non-citizen, or of which more than a minority or the number of its directors necessary to constitute a quorum are Non-citizens; (4) any corporation organized under the laws of any foreign government; (5) any corporation of which 25% or greater interest is owned beneficially or of record, or may be voted by, a Non-citizen or Non-citizens, or which by any other means whatsoever is controlled by or in which control is permitted to be exercised by a Non-citizen or Non-citizens (the General Partner being authorized to determine reasonably the meaning of "control" for this purpose); (6) any partnership or association which is controlled by a Non-citizen or Non-citizens; or (7) any person (including an individual, partnership, corporation or association) who acts as representative of or fiduciary for any person described in clauses (1) through (6) above.

"Non-citizen Assignee" means a Person whom the General Partner has determined in its discretion does not constitute an Eligible Citizen and as to whose Partnership Interest the General Partner has become the Substituted Limited Partner pursuant to Section 4.9.

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"Nonrecourse Built-in Gain" means with respect to any Contributed Properties or Adjusted Properties that are subject to a mortgage or pledge securing a Nonrecourse Liability, the amount of any taxable gain that would be allocated to the Partners pursuant to Sections 6.2(b)(i)(A), 6.2(b)(ii)(A) and 6.2(b)(iii) if such properties were disposed of in a taxable transaction in full satisfaction of such liabilities and for no other consideration.

"Nonrecourse Deductions" means any and all items of loss, deduction or expenditure (including, without limitation, any expenditure described in Section 705(a)(2)(B) of the Code) that, in accordance with the principles of Treasury Regulation Section 1.704-2(b), are attributable to a Nonrecourse Liability.

"Nonrecourse Liability" has the meaning set forth in Treasury Regulation
Section 1.752-1(a)(2).

"Notice of Election to Purchase" has the meaning assigned to such term in
Section 15.1(b).

"Omnibus Agreement" means that Omnibus Agreement, dated as of the Closing Date, among Penn Octane Corporation, the General Partner, the Partnership and the Operating Partnership.

"Operating Expenditures" means all Partnership Group expenditures, including, but not limited to, taxes, reimbursements of the General Partner, repayment of Working Capital Borrowings, debt service payments and capital expenditures, subject to the following:

(a) Payments (including prepayments) of principal of and premium on indebtedness other than Working Capital Borrowings shall not constitute Operating

(b) Operating Expenditures shall not include (i) capital expenditures made for Acquisitions or for Capital Improvements, (ii) payment of transaction expenses relating to Interim Capital Transactions or (iii) distributions to Partners. Where capital expenditures are made in part for Acquisitions or for Capital Improvements and in part for other purposes, the General Partner's good faith allocation between the amounts paid for each shall be conclusive.

"Operating Partnership" means Rio Vista Operating Partnership L.P., a Delaware limited partnership, and any successors thereto.

"Operating Partnership Agreement" means the Partnership Agreement of the Operating Partnership, as it may be amended, supplemented or restated from time to time.

"Operating Surplus" means, with respect to any period ending prior to the Liquidation Date, on a cumulative basis and without duplication,

(a) the sum of (i) all cash and cash equivalents of the Partnership Group on hand as of the close of business on the Closing Date, (ii) all cash receipts of the Partnership Group for the period beginning on the Closing Date and ending with the last day

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of such period, other than cash receipts from Interim Capital Transactions (except to the extent specified in Section 6.5) and (iii) all cash receipts of the Partnership Group after the end of such period but on or before the date of determination of Operating Surplus with respect to such period resulting from Working Capital Borrowings, less

(b) the sum of (i) Operating Expenditures for the period beginning on the Closing Date and ending with the last day of such period and (ii) the amount of cash reserves that is necessary or advisable in the reasonable discretion of the General Partner to provide funds for future Operating Expenditures; provided, however, that disbursements made (including contributions to a Group Member or disbursements on behalf of a Group Member) or cash reserves established, increased or reduced after the end of such period but on or before the date of determination of Available Cash with respect to such period shall be deemed to have been made, established, increased or reduced, for purposes of determining Operating Surplus, within such period if the General Partner so determines.

Notwithstanding the foregoing, "Operating Surplus" with respect to the Quarter in which the Liquidation Date occurs and any subsequent Quarter shall equal zero.

"Opinion of Counsel" means a written opinion of counsel (who may be regular counsel to the Partnership or the General Partner or any of its Affiliates) acceptable to the General Partner in its reasonable discretion.

"Organizational Limited Partner" means Penn Octane Corporation in its capacity as the organizational limited partner of the Partnership pursuant to this Agreement.

"Outstanding" means, with respect to Partnership Securities, all Partnership Securities that are issued by the Partnership and reflected as outstanding on the Partnership's books and records as of the date of determination; provided, however, that if at any time any Person or Group (other than the General Partner or its Affiliates) beneficially owns 20% or more of any Outstanding Partnership Securities of any class then Outstanding, all Partnership Securities owned by such Person or Group shall not be voted on any matter and shall not be considered to be Outstanding when sending notices of a meeting of Limited Partners to vote on any matter (unless otherwise required by law), calculating required votes, determining the presence of a quorum or for other similar purposes under this Agreement, except that Common Units so owned shall be considered to be Outstanding for purposes of Section 11.1(b)(iv) (such Common Units shall not, however, be treated as a separate class of Partnership Securities for purposes of this Agreement); provided, further, that the foregoing limitation shall not apply (i) to any Person or Group who acquired 20% or more of any Outstanding Partnership Securities of any class then Outstanding directly from the General Partner or its Affiliates, including any Person or Group who acquired 20% or more of any Outstanding Partnership Securities in the Distribution, (ii) to any Person or Group who acquired 20% or more of any Outstanding Partnership Securities of any class then Outstanding directly or indirectly from a Person or Group described in clause (i) provided that the General Partner shall have notified such Person or Group in writing that such limitation shall not apply, or (iii) to any Person or Group who acquired 20% or more of any

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Partnership Securities issued by the Partnership with the prior approval of the Board of Managers of the General Partner; provided further, that the provisions contained herein may be amended by the General Partner as provided in Section 13.1 hereof.

"Partner Nonrecourse Debt" has the meaning set forth in Treasury Regulation
Section 1.704-2(b)(4).

"Partner Nonrecourse Debt Minimum Gain" has the meaning set forth in Treasury Regulation Section 1.704-2(i)(2).

"Partner Nonrecourse Deductions" means any and all items of loss, deduction or expenditure (including, without limitation, any expenditure described in
Section 705(a)(2)(B) of the Code) that, in accordance with the principles of Treasury Regulation Section 1.704-2(i), are attributable to a Partner Nonrecourse Debt.

"Partners" means the General Partner and the Limited Partners.

"Partnership" means Rio Vista Energy Partners L.P., a Delaware limited partnership, and any successors thereto.

"Partnership Group" means the Partnership, the Operating Partnership and any Subsidiary of any such entity, treated as a single consolidated entity.

"Partnership Interest" means an interest in the Partnership, which shall include the General Partner Interest and Limited Partner Interests.

"Partnership Minimum Gain" means that amount determined in accordance with the principles of Treasury Regulation Section 1.704-2(d).

"Partnership Security" means any class or series of equity interest in the Partnership (but excluding any options, rights, warrants and appreciation rights relating to an equity interest in the Partnership), including without limitation, Common Units and Incentive Distribution Rights.

"Percentage Interest" means as of any date of determination (a) as to the General Partner (in its capacity as General Partner without reference to any Limited Partner Interests held by it), 2.0%, (b) as to any Unitholder or Assignee holding Units, the product obtained by multiplying (i) 98% less the percentage applicable to paragraph (c) by (ii) the quotient obtained by dividing (A) the number of Units held by such Unitholder or Assignee by (B) the total number of all Outstanding Units, and (c) as to the holders of additional Partnership Securities issued by the Partnership in accordance with Section 5.6, the percentage established as a part of such issuance. The Percentage Interest with respect to an Incentive Distribution Right shall at all times be zero.

"Per Unit Capital Amount" means, as of any date of determination, the Capital Account, stated on a per Unit basis, underlying any Unit held by a Person other than the General Partner or any Affiliate of the General Partner who holds Units.

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"Person" means an individual or a corporation, limited liability company, partnership, joint venture, trust, unincorporated organization, association, government agency or political subdivision thereof or other entity.

"Pro Rata" means (a) when modifying Units or any class thereof, apportioned equally among all designated Units in accordance with their relative Percentage Interests, (b) when modifying Partners and Assignees, apportioned among all Partners and Assignees in accordance with their relative Percentage Interests and (c) when modifying holders of Incentive Distribution Rights, apportioned equally among all holders of Incentive Distribution Rights in accordance with the relative number of Incentive Distribution Rights held by each such holder.

"Purchase Date" means the date determined by the General Partner as the date for purchase of all Outstanding Units of a certain class (other than Units owned by the General Partner and its Affiliates) pursuant to Article XV.

"Quarter" means, unless the context requires otherwise, a fiscal quarter, or, with respect to the first fiscal quarter after the Closing Date, the portion of such fiscal quarter after the Closing Date, of the Partnership.

"Recapture Income" means any gain recognized by the Partnership (computed without regard to any adjustment required by Section 734 or Section 743 of the Code) upon the disposition of any property or asset of the Partnership, which gain is characterized as ordinary income because it represents the recapture of deductions previously taken with respect to such property or asset.

"Record Date" means the date established by the General Partner for determining (a) the identity of the Record Holders entitled to notice of, or to vote at, any meeting of Limited Partners or entitled to vote by ballot or give approval of Partnership action in writing without a meeting or entitled to exercise rights in respect of any lawful action of Limited Partners or (b) the identity of Record Holders entitled to receive any report or distribution or to participate in any offer.

"Record Holder" means the Person in whose name a Common Unit is registered on the books of the Transfer Agent as of the opening of business on a particular Business Day, or with respect to other Partnership Securities, the Person in whose name any such other Partnership Security is registered on the books which the General Partner has caused to be kept as of the opening of business on such Business Day.

"Redeemable Interests" means any Partnership Interests for which a redemption notice has been given, and has not been withdrawn, pursuant to
Section 4.10.

"Registration Statement" means the Registration Statement on Form 10 (File No. 0-50394) as it has been or as it may be amended or supplemented from time to time, filed by the Partnership with the Commission under the Securities Act to register the Common Units distributed in the Distribution.

"Remaining Net Positive Adjustments" means as of the end of any taxable period, (i) with respect to the Unitholders holding Common Units, the excess of
(a) the Net Positive

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Adjustments of the Unitholders holding Common Units as of the end of such period over (b) the sum of those Partners' Share of Additional Book Basis Derivative Items for each prior taxable period, (ii) with respect to the General Partner (as holder of the General Partner Interest), the excess of (a) the Net Positive Adjustments of the General Partner as of the end of such period over (b) the sum of the General Partner's Share of Additional Book Basis Derivative Items with respect to the General Partner Interest for each prior taxable period, and (iii) with respect to the holders of Incentive Distribution Rights, the excess of (a) the Net Positive Adjustments of the holders of Incentive Distribution Rights as of the end of such period over (b) the sum of the Share of Additional Book Basis Derivative Items of the holders of the Incentive Distribution Rights for each prior taxable period.

"Required Allocations" means (a) any limitation imposed on any allocation of Net Losses or Net Termination Losses under Section 6.1(b) and (b) any allocation of an item of income, gain, loss or deduction pursuant to Section 6.1(d)(i), 6.1(d)(ii), 6.1(d)(iv), 6.1(d)(vii), 6.1(d)(ix) or 6.1(d)(x).

"Residual Gain" or "Residual Loss" means any item of gain or loss, as the case may be, of the Partnership recognized for federal income tax purposes resulting from a sale, exchange or other disposition of a Contributed Property or Adjusted Property, to the extent such item of gain or loss is not allocated pursuant to Section 6.2(b)(i)(A) or 6.2(b)(ii)(A), respectively, to eliminate Book-Tax Disparities.

"Second Liquidation Target Amount" has the meaning assigned to such term in
Section 6.1(c)(i)(D).

"Second Target Distribution" means $0.362 per Unit per Quarter (or, with respect to the period commencing on the Closing Date and ending on the last day of the calendar quarter that includes the Closing Date, it means the product of $0.362 multiplied by a fraction of which the numerator is equal to the number of days in such period and of which the denominator is 91), subject to adjustment in accordance with Sections 6.6 and 6.9.

"Securities Act" means the Securities Act of 1933, as amended, supplemented or restated from time to time and any successor to such statute.

"Share of Additional Book Basis Derivative Items" means in connection with any allocation of Additional Book Basis Derivative Items for any taxable period,
(i) with respect to the Unitholders holding Common Units, the amount that bears the same ratio to such Additional Book Basis Derivative Items as the Unitholders' Remaining Net Positive Adjustments as of the end of such period bears to the Aggregate Remaining Net Positive Adjustments as of that time, (ii) with respect to the General Partner (as holder of the General Partner Interest), the amount that bears the same ratio to such Additional Book Basis Derivative Items as the General Partner's Remaining Net Positive Adjustments as of the end of such period bears to the Aggregate Remaining Net Positive Adjustment as of that time, and (iii) with respect to the Partners holding Incentive Distribution Rights, the amount that bears the same ratio to such Additional Book Basis Derivative Items as the Remaining Net Positive Adjustments of the Partners holding the

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Incentive Distribution Rights as of the end of such period bears to the Aggregate Remaining Net Positive Adjustments as of that time.

"Special Approval" means approval by a majority of the members of the Conflicts Committee.

"Subsidiary" means, with respect to any Person, (a) a corporation of which more than 50% of the voting power of shares entitled (without regard to the occurrence of any contingency) to vote in the election of directors or other governing body of such corporation is owned, directly or indirectly, at the date of determination, by such Person, by one or more Subsidiaries of such Person or a combination thereof, (b) a partnership (whether general or limited) in which such Person or a Subsidiary of such Person is, at the date of determination, a general or limited partner of such partnership, but only if more than 50% of the partnership interests of such partnership (considering all of the partnership interests of the partnership as a single class) is owned, directly or indirectly, at the date of determination, by such Person, by one or more Subsidiaries of such Person, or a combination thereof, or (c) any other Person (other than a corporation or a partnership) in which such Person, one or more Subsidiaries of such Person, or a combination thereof, directly or indirectly, at the date of determination, has (i) at least a majority ownership interest or
(ii) the power to elect or direct the election of a majority of the directors or other governing body of such Person.

"Substituted Limited Partner" means a Person who is admitted as a Limited Partner to the Partnership pursuant to Section 10.2 in place of and with all the rights of a Limited Partner and who is shown as a Limited Partner on the books and records of the Partnership.

"Surviving Business Entity" has the meaning assigned to such term in
Section 14.2(b).

"Third Liquidation Target Amount" has the meaning assigned to such term in
Section 6.1(c)(i)(E).

"Third Target Distribution" means $0.462 per Unit per Quarter (or, with respect to the period commencing on the Closing Date and ending on the last day of the calendar quarter that includes the Closing Date, it means the product of $0.462 multiplied by a fraction of which the numerator is equal to the number of days in such period and of which the denominator is 91), subject to adjustment in accordance with Sections 6.6 and 6.9.

"Trading Day" means a day on which the principal National Securities Exchange on which such Limited Partner Interests of any class are listed or admitted to trading is open for the transaction of business or, if Limited Partner Interests of a class are not listed or admitted to trading on any National Securities Exchange, a day on which banking institutions in New York City generally are open.

"transfer" has the meaning assigned to such term in Section 4.4(a).

"Transfer Agent" means such bank, trust company or other Person (including the General Partner or one of its Affiliates) as shall be appointed from time to time by the Partnership to act as registrar and transfer agent for the Common Units; provided that if no Transfer Agent is

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specifically designated for any other Partnership Securities, the General Partner shall act in such capacity.

"Transfer Application" means an application and agreement for transfer of Units in the form set forth on the back of a Certificate or in a form substantially to the same effect in a separate instrument.

"Unit" means a Partnership Security that is designated as a "Unit" and shall include Common Units but shall not include (i) a General Partner Interest or (ii) Incentive Distribution Rights.

"Unit Majority" means at least a majority of the Outstanding Common Units.

"Unitholders" means the holders of Units.

"Unpaid MQD" has the meaning assigned to such term in Section 6.1(c)(i)(B).

"Unrealized Gain" attributable to any item of Partnership property means, as of any date of determination, the excess, if any, of (a) the fair market value of such property as of such date (as determined under Section 5.5(d)) over
(b) the Carrying Value of such property as of such date (prior to any adjustment to be made pursuant to Section 5.5(d) as of such date).

"Unrealized Loss" attributable to any item of Partnership property means, as of any date of determination, the excess, if any, of (a) the Carrying Value of such property as of such date (prior to any adjustment to be made pursuant to
Section 5.5(d) as of such date) over (b) the fair market value of such property as of such date (as determined under Section 5.5(d)).

"Unrecovered Capital" means at any time, with respect to a Unit, the Initial Unit Capital Account less the sum of all distributions constituting Capital Surplus theretofore made in respect of an Initial Common Unit and any distributions of cash (or the Net Agreed Value of any distributions in kind) in connection with the dissolution and liquidation of the Partnership theretofore made in respect of an Initial Common Unit, adjusted as the General Partner determines to be appropriate to give effect to any distribution, subdivision or combination of such Units.

"U.S. GAAP" means United States Generally Accepted Accounting Principles consistently applied.

"Withdrawal Opinion of Counsel" has the meaning assigned to such term in
Section 11.1(b).

"Working Capital Borrowings" means borrowings used solely for working capital purposes or to pay distributions to Partners made pursuant to a credit facility or other arrangement to the extent such borrowings are required to be reduced to a relatively small amount each year (or for the year in which the Initial Offering is consummated, the 12-month period beginning on the Closing Date) for an economically meaningful period of time.

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SECTION 1.2 Construction. Unless the context requires otherwise: (a) any pronoun used in this Agreement shall include the corresponding masculine, feminine or neuter forms, and the singular form of nouns, pronouns and verbs shall include the plural and vice versa; (b) references to Articles and Sections refer to Articles and Sections of this Agreement; and (c) the term "include" or "includes" means includes, without limitation, and "including" means including, without limitation.

ARTICLE II

ORGANIZATION

SECTION 2.1 Formation. The General Partner and the Organizational Limited Partner have previously formed the Partnership as a limited partnership pursuant to the provisions of the Delaware Act and hereby amend and restate the original Agreement of Limited Partnership of Rio Vista Energy Partners L.P. in its entirety. This amendment and restatement shall become effective on the date of this Agreement. Except as expressly provided to the contrary in this Agreement, the rights, duties (including fiduciary duties), liabilities and obligations of the Partners and the administration, dissolution and termination of the Partnership shall be governed by the Delaware Act. All Partnership Interests shall constitute personal property of the owner thereof for all purposes and a Partner has no interest in specific Partnership property.

SECTION 2.2 Name. The name of the Partnership shall be "Rio Vista

Energy Partners L.P." The Partnership's business may be conducted under any other name or names deemed necessary or appropriate by the General Partner in its sole discretion, including the name of the General Partner. The words "Limited Partnership," "L.P.," "Ltd." or similar words or letters shall be included in the Partnership's name where necessary for the purpose of complying with the laws of any jurisdiction that so requires. The General Partner in its discretion may change the name of the Partnership at any time and from time to time and shall notify the Limited Partners of such change in the next regular communication to the Limited Partners.

SECTION 2.3 Registered Office; Registered Agent; Principal Office; Other Offices. Unless and until changed by the General Partner, the registered office of the Partnership in the State of Delaware shall be located at 615 South DuPont Highway, City of Dover, County of Kent, Delaware 19901, and the registered agent for service of process on the Partnership in the State of Delaware at such registered office shall be Capitol Services, Inc. The principal office of the Partnership shall be located at 820 Gessner Road, Suite 1285, Houston, Texas 77024 or such other place as the General Partner may from time to time designate by notice to the Limited Partners. The Partnership may maintain offices at such other place or places within or outside the State of Delaware as the General Partner deems necessary or appropriate. The address of the General Partner shall be 820 Gessner Road, Suite 1285, Houston, Texas 77024 or such other place as the General Partner may from time to time designate by notice to the Limited Partners.

SECTION 2.4 Purpose and Business. The purpose and nature of the business to be conducted by the Partnership shall be to (a) own the equity of the general partner of the Operating Partnership and to serve as a limited partner of the Operating Partnership and, in connection therewith, to exercise all the rights and powers conferred upon the Partnership as a

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partner of the Operating Partnership pursuant to the Operating Partnership Agreement or otherwise, (b) engage directly in, or enter into or form any corporation, partnership, joint venture, limited liability company or other arrangement to engage indirectly in, any business activity that the Operating Partnership is permitted to engage in by the Operating Partnership Agreement or that its subsidiaries are permitted to engage in by their limited liability company or partnership agreements and, in connection therewith, to exercise all of the rights and powers conferred upon the Partnership pursuant to the agreements relating to such business activity, (c) engage directly in, or enter into or form any corporation, partnership, joint venture, limited liability company or other arrangement to engage indirectly in, any business activity that is approved by the General Partner and which lawfully may be conducted by a limited partnership organized pursuant to the Delaware Act and, in connection therewith, to exercise all of the rights and powers conferred upon the Partnership pursuant to the agreements relating to such business activity; provided, however, that the General Partner reasonably determines, as of the date of the acquisition or commencement of such activity, that such activity (i) generates "qualifying income" (as such term is defined pursuant to Section 7704 of the Code) or a Subsidiary or a Partnership activity that generates qualifying income or (ii) enhances the operations of an activity of the Operating Partnership, and (d) do anything necessary or appropriate to the foregoing, including the making of capital contributions or loans to a Group Member. The General Partner has no obligation or duty to the Partnership, the Limited Partners or the Assignees to propose or approve, and in its discretion may decline to propose or approve, the conduct by the Partnership of any business.

SECTION 2.5 Powers. The Partnership shall be empowered to do any and all acts and things necessary, appropriate, proper, advisable, incidental to or convenient for the furtherance and accomplishment of the purposes and business described in Section 2.4 and for the protection and benefit of the Partnership.

SECTION 2.6 Power of Attorney. Each Limited Partner and each Assignee hereby constitutes and appoints the General Partner and, if a Liquidator shall have been selected pursuant to Section 12.3, the Liquidator (and any successor to the Liquidator by merger, transfer, assignment, election or otherwise) and each of their authorized officers and attorneys-in-fact, as the case may be, with full power of substitution, as his true and lawful agent and attorney-in-fact, with full power and authority in his name, place and stead, to:

(i) execute, swear to, acknowledge, deliver, file and record in the appropriate public offices (A) all certificates, documents and other instruments (including this Agreement and the Certificate of Limited Partnership and all amendments or restatements hereof or thereof) that the General Partner or the Liquidator deems necessary or appropriate to form, qualify or continue the existence or qualification of the Partnership as a limited partnership (or a partnership in which the limited partners have limited liability) in the State of Delaware and in all other jurisdictions in which the Partnership may conduct business or own property; (B) all certificates, documents and other instruments that the General Partner or the Liquidator deems necessary or appropriate to reflect, in accordance with its terms, any amendment, change, modification or restatement of this Agreement; (C) all certificates, documents and other instruments (including conveyances and a

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certificate of cancellation) that the General Partner or the Liquidator deems necessary or appropriate to reflect the dissolution and liquidation of the Partnership pursuant to the terms of this Agreement; (D) all certificates, documents and other instruments relating to the admission, withdrawal, removal or substitution of any Partner pursuant to, or other events described in, Article IV, X, XI or XII; (E) all certificates, documents and other instruments relating to the determination of the rights, preferences and privileges of any class or series of Partnership Securities issued pursuant to Section 5.6; and (F) all certificates, documents and other instruments (including agreements and a certificate of merger) relating to a merger or consolidation of the Partnership pursuant to Article XIV; and

(ii) execute, swear to, acknowledge, deliver, file and record all ballots, consents, approvals, waivers, certificates, documents and other instruments necessary or appropriate, in the discretion of the General Partner or the Liquidator, to make, evidence, give, confirm or ratify any vote, consent, approval, agreement or other action that is made or given by the Partners hereunder or is consistent with the terms of this Agreement or is necessary or appropriate, in the discretion of the General Partner or the Liquidator, to effectuate the terms or intent of this Agreement; provided, that when required by Section 13.3 or any other provision of this Agreement that establishes a percentage of the Limited Partners or of the Limited Partners of any class or series required to take any action, the General Partner and the Liquidator may exercise the power of attorney made in this Section 2.6(a)(ii) only after the necessary vote, consent or approval of the Limited Partners or of the Limited Partners of such class or series, as applicable. Nothing contained in this Section 2.6(a) shall be construed as authorizing the General Partner to amend this Agreement except in accordance with Article XIII or as may be otherwise expressly provided for in this Agreement. b) The foregoing power of attorney is hereby declared to be irrevocable and a power coupled with an interest, and it shall survive and, to the maximum extent permitted by law, not be affected by the subsequent death, incompetency, disability, incapacity, dissolution, bankruptcy or termination of any Limited Partner or Assignee and the transfer of all or any portion of such Limited Partner's or Assignee's Partnership Interest and shall extend to such Limited Partner's or Assignee's heirs, successors, assigns and personal representatives. Each Limited Partner or Assignee hereby agrees to be bound by any representation made by the General Partner or the Liquidator acting in good faith pursuant to such power of attorney; and each Limited Partner or Assignee hereby waives, to the maximum extent permitted by law, any and all defenses that may be available to contest, negate or disaffirm the action of the General Partner or the Liquidator taken in good faith under such power of attorney. Each Limited Partner or Assignee shall execute and deliver to the General Partner or the Liquidator, within 15 days after receipt of the request therefor, such further designation, powers of attorney and other instruments as the General Partner or the Liquidator deems necessary to effectuate this Agreement and the purposes of the Partnership.

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SECTION 2.7 Term. The term of the Partnership commenced upon the

filing of the Certificate of Limited Partnership in accordance with the Delaware Act and shall continue in existence until the dissolution of the Partnership in accordance with the provisions of Article XII. The existence of the Partnership as a separate legal entity shall continue until the cancellation of the Certificate of Limited Partnership as provided in the Delaware Act.

SECTION 2.8 Title to Partnership Assets. Title to Partnership assets, whether real, personal or mixed and whether tangible or intangible, shall be deemed to be owned by the Partnership as an entity, and no Partner or Assignee, individually or collectively, shall have any ownership interest in such Partnership assets or any portion thereof. Title to any or all of the Partnership assets may be held in the name of the Partnership, the General Partner, one or more of its Affiliates or one or more nominees, as the General Partner may determine. The General Partner hereby declares and warrants that any Partnership assets for which record title is held in the name of the General Partner or one or more of its Affiliates or one or more nominees shall be held by the General Partner or such Affiliate or nominee for the use and benefit of the Partnership in accordance with the provisions of this Agreement; provided, however, that the General Partner shall use reasonable efforts to cause record title to such assets (other than those assets in respect of which the General Partner determines that the expense and difficulty of conveyancing makes transfer of record title to the Partnership impracticable) to be vested in the Partnership as soon as reasonably practicable; provided, further, that, prior to the withdrawal or removal of the General Partner or as soon thereafter as practicable, the General Partner shall use reasonable efforts to effect the transfer of record title to the Partnership and, prior to any such transfer, will provide for the use of such assets in a manner satisfactory to the General Partner. All Partnership assets shall be recorded as the property of the Partnership in its books and records, irrespective of the name in which record title to such Partnership assets is held.

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ARTICLE III

RIGHTS OF LIMITED PARTNERS

SECTION 3.1 Limitation of Liability. The Limited Partners and the Assignees shall have no liability under this Agreement except as expressly provided in this Agreement or the Delaware Act.

SECTION 3.2 Management of Business. No Limited Partner or Assignee, in its capacity as such, shall participate in the operation, management or control (within the meaning of the Delaware Act) of the Partnership's business, transact any business in the Partnership's name or have the power to sign documents for or otherwise bind the Partnership. Any action taken by any Affiliate of the General Partner or any officer, director, employee, manager, member, general partner, agent or trustee of the General Partner or any of its Affiliates, or any officer, director, employee, manager, member, general partner, agent or trustee of a Group Member, in its capacity as such, shall not be deemed to be participation in the control of the business of the Partnership by a limited partner of the Partnership (within the meaning of Section 17-303(a) of the Delaware Act) and shall not affect, impair or eliminate the limitations on the liability of the Limited Partners or Assignees under this Agreement.

SECTION 3.3 Outside Activities of the Limited Partners. Subject to the provisions of Section 7.5 and the Omnibus Agreement, which shall continue to be applicable to the Persons referred to therein, regardless of whether such Persons shall also be Limited Partners or Assignees, any Limited Partner or Assignee shall be entitled to and may have business interests and engage in business activities in addition to those relating to the Partnership, including business interests and activities in direct competition with the Partnership Group. Neither the Partnership nor any of the other Partners or Assignees shall have any rights by virtue of this Agreement in any business ventures of any Limited Partner or Assignee.

SECTION 3.4 Rights of Limited Partners.

(a) In addition to other rights provided by this Agreement or by applicable law, and except as limited by Section 3.4(b), each Limited Partner shall have the right, for a purpose reasonably related to such Limited Partner's interest as a limited partner in the Partnership, upon reasonable written demand and at such Limited Partner's own expense:

(i) to obtain true and full information regarding the status of the business and financial condition of the Partnership;

(ii) promptly after becoming available, to obtain a copy of the Partnership's federal, state and local income tax returns for each year;

(iii) to have furnished to him a current list of the name and last known business, residence or mailing address of each Partner;

(iv) to have furnished to him a copy of this Agreement and the Certificate of Limited Partnership and all amendments thereto, together with a copy of

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the executed copies of all powers of attorney pursuant to which this Agreement, the Certificate of Limited Partnership and all amendments thereto have been executed;

(v) to obtain true and full information regarding the amount of cash and a description and statement of the Net Agreed Value of any other Capital Contribution by each Partner and which each Partner has agreed to contribute in the future, and the date on which each became a Partner; and

(vi) to obtain such other information regarding the affairs of the Partnership as is just and reasonable.

(b) The General Partner may keep confidential from the Limited Partners and Assignees, for such period of time as the General Partner deems reasonable,
(i) any information that the General Partner reasonably believes to be in the nature of trade secrets or (ii) other information the disclosure of which the General Partner in good faith believes (A) is not in the best interests of the Partnership Group, (B) could damage the Partnership Group or (C) that any Group Member is required by law or by agreement with any third party to keep confidential (other than agreements with Affiliates of the Partnership the primary purpose of which is to circumvent the obligations set forth in this
Section 3.4).

ARTICLE IV

CERTIFICATES; RECORD HOLDERS; TRANSFER OF PARTNERSHIP INTERESTS; REDEMPTION OF
PARTNERSHIP INTERESTS

SECTION 4.1 Certificates. Upon the Partnership's issuance of Common Units to any Person, the Partnership shall issue one or more Certificates in the name of such Person evidencing the number of such Units being so issued. In addition, (a) upon the General Partner's request, the Partnership shall issue to it one or more Certificates in the name of the General Partner evidencing its interests in the Partnership and (b) upon the request of any Person owning Incentive Distribution Rights or any other Partnership Securities other than Common Units, the Partnership shall issue to such Person one or more certificates evidencing such Incentive Distribution Rights or other Partnership Securities other than Common Units. Certificates shall be executed on behalf of the Partnership by the Chairman of the Board, President or any Vice President and the Secretary or any Assistant Secretary of the General Partner. No Common Unit Certificate shall be valid for any purpose until it has been countersigned by the Transfer Agent; provided, however, that if the General Partner elects to issue Common Units in global form, the Common Unit Certificates shall be valid upon receipt of a certificate from the Transfer Agent certifying that the Common Units have been duly registered in accordance with the directions of the Partnership.

SECTION 4.2 Mutilated, Destroyed, Lost or Stolen Certificates.

(a) If any mutilated Certificate is surrendered to the Transfer Agent, the appropriate officers of the General Partner on behalf of the Partnership shall execute, and the

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Transfer Agent shall countersign and deliver in exchange therefor, a new Certificate evidencing the same number and type of Partnership Securities as the Certificate so surrendered.

(b) The appropriate officers of the General Partner on behalf of the Partnership shall execute and deliver, and the Transfer Agent shall countersign a new Certificate in place of any Certificate previously issued if the Record Holder of the Certificate:

(i) makes proof by affidavit, in form and substance satisfactory to the General Partner, that a previously issued Certificate has been lost, destroyed or stolen;

(ii) requests the issuance of a new Certificate before the General Partner has notice that the Certificate has been acquired by a purchaser for value in good faith and without notice of an adverse claim;

(iii) if requested by the General Partner, delivers to the General Partner a bond, in form and substance satisfactory to the General Partner, with surety or sureties and with fixed or open penalty as the General Partner may reasonably direct, in its sole discretion, to indemnify the Partnership, the Partners, the General Partner and the Transfer Agent against any claim that may be made on account of the alleged loss, destruction or theft of the Certificate; and

(iv) satisfies any other reasonable requirements imposed by the General Partner.

If a Limited Partner or Assignee fails to notify the General Partner within a reasonable time after he has notice of the loss, destruction or theft of a Certificate, and a transfer of the Limited Partner Interests represented by the Certificate is registered before the Partnership, the General Partner or the Transfer Agent receives such notification, the Limited Partner or Assignee shall be precluded from making any claim against the Partnership, the General Partner or the Transfer Agent for such transfer or for a new Certificate.

(c) As a condition to the issuance of any new Certificate under this
Section 4.2, the General Partner may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in relation thereto and any other expenses (including the fees and expenses of the Transfer Agent) reasonably connected therewith.

SECTION 4.3 Record Holders. The Partnership shall be entitled to recognize the Record Holder as the Partner or Assignee with respect to any Partnership Interest and, accordingly, shall not be bound to recognize any equitable or other claim to or interest in such Partnership Interest on the part of any other Person, regardless of whether the Partnership shall have actual or other notice thereof, except as otherwise provided by law or any applicable rule, regulation, guideline or requirement of any National Securities Exchange on which such Partnership Interests are listed for trading. Without limiting the foregoing, when a Person (such as a broker, dealer, bank,

26

trust company or clearing corporation or an agent of any of the foregoing) is acting as nominee, agent or in some other representative capacity for another Person in acquiring and/or holding Partnership Interests, as between the Partnership on the one hand, and such other Persons on the other, such representative Person (a) shall be the Partner or Assignee (as the case may be) of record and beneficially, (b) must execute and deliver a Transfer Application and (c) shall be bound by this Agreement and shall have the rights and obligations of a Partner or Assignee (as the case may be) hereunder and as, and to the extent, provided for herein.

SECTION 4.4 Transfer Generally.

(a) The term "transfer," when used in this Agreement with respect to a Partnership Interest, shall be deemed to refer to a transaction by which the General Partner assigns its General Partner Interest to another Person who becomes the general partner of the Partnership, by which the holder of a Limited Partner Interest assigns such Limited Partner Interest to another Person who is or becomes a Limited Partner or an Assignee, and includes a sale, assignment, gift, pledge, encumbrance, hypothecation, mortgage, exchange or any other disposition by law or otherwise.

(b) No Partnership Interest shall be transferred, in whole or in part, except in accordance with the terms and conditions set forth in this Article IV. Any transfer or purported transfer of a Partnership Interest not made in accordance with this Article IV shall be null and void.

(c) Nothing contained in this Agreement shall be construed to prevent a disposition by any member of the General Partner of any or all of the limited liability company interests of the General Partner. At any time, any member of the General Partner may sell or transfer all or part of such member's limited liability company interests in the General Partner without Unitholder approval.

SECTION 4.5 Registration and Transfer of Limited Partner Interests.

(a) The Partnership shall keep or cause to be kept on behalf of the Partnership a register in which, subject to such reasonable regulations as it may prescribe and subject to the provisions of Section 4.5(b), the Partnership will provide for the registration and transfer of Limited Partner Interests. The Transfer Agent is hereby appointed registrar and transfer agent for the purpose of registering Common Units and transfers of such Common Units as herein provided. The Partnership shall not recognize transfers of Certificates evidencing Limited Partner Interests unless such transfers are effected in the manner described in this Section 4.5. Upon surrender of a Certificate for registration of transfer of any Limited Partner Interests evidenced by a Certificate, and subject to the provisions of Section 4.5(b), the appropriate officers of the General Partner on behalf of the Partnership shall execute and deliver, and in the case of Common Units, the Transfer Agent shall countersign and deliver, in the name of the holder or the designated transferee or transferees, as required pursuant to the holder's instructions, one or more new Certificates evidencing the same aggregate number and type of Limited Partner Interests as was evidenced by the Certificate so surrendered.

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(b) Except as otherwise provided in Section 4.9, the Partnership shall not recognize any transfer of Limited Partner Interests until the Certificates evidencing such Limited Partner Interests are surrendered for registration of transfer and such Certificates are accompanied by a Transfer Application duly executed by the transferee (or the transferee's attorney-in-fact duly authorized in writing). No charge shall be imposed by the Partnership for such transfer; provided, that as a condition to the issuance of any new Certificate under this
Section 4.5, the Partnership may require the payment of a sum sufficient to cover any tax or other governmental charge that may be imposed with respect thereto.

(c) Limited Partner Interests may be transferred only in the manner described in this Section 4.5. The transfer of any Limited Partner Interests and the admission of any new Limited Partner shall not constitute an amendment to this Agreement.

(d) Until admitted as a Substituted Limited Partner pursuant to Section 10.2, the Record Holder of a Limited Partner Interest shall be an Assignee in respect of such Limited Partner Interest. Limited Partners may include custodians, nominees or any other individual or entity in its own or any representative capacity.

(e) A transferee of a Limited Partner Interest who has completed and delivered a Transfer Application shall be deemed to have (i) requested admission as a Substituted Limited Partner, (ii) agreed to comply with and be bound by and to have executed this Agreement, (iii) represented and warranted that such transferee has the right, power and authority and, if an individual, the capacity to enter into this Agreement, (iv) granted the powers of attorney set forth in this Agreement and (v) given the consents and approvals and made the waivers contained in this Agreement.

(f) The General Partner and its Affiliates shall have the right at any time to transfer their Common Units, if any, to one or more Persons.

SECTION 4.6 Transfer of the General Partner's General Partner Interest.

(a) Subject to Section 4.6(c) below, prior to October 31, 2008, the General Partner shall not transfer all or any part of its General Partner Interest to a Person unless such transfer (i) has been approved by the prior written consent or vote of the holders of at least a majority of the Outstanding Common Units (excluding Common Units held by the General Partner and its Affiliates) or (ii) is of all, but not less than all, of its General Partner Interest to (A) an Affiliate of the General Partner (other than an individual) or (B) another Person (other than an individual) in connection with the merger or consolidation of the General Partner with or into another Person (other than an individual) or the transfer by the General Partner of all or substantially all of its assets to another Person (other than an individual).

(b) Subject to Section 4.6(c) below, on or after October 31, 2008, the General Partner may transfer all or any of its General Partner Interest without Unitholder approval.

(c) Notwithstanding anything herein to the contrary, no transfer by the General Partner of all or any part of its General Partner Interest to another Person shall be permitted unless (i) the transferee agrees to assume the rights and duties of the General Partner under this

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Agreement and to be bound by the provisions of this Agreement, (ii) the Partnership receives an Opinion of Counsel that such transfer would not result in the loss of limited liability of any Limited Partner or of any limited partner of the Operating Partnership or cause the Partnership or the Operating Partnership to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not already so treated or taxed) and (iii) such transferee also agrees to purchase all (or the appropriate portion thereof, if applicable) of the partnership or membership interest of the General Partner as the general partner or managing member, if any, of each other Group Member. In the case of a transfer pursuant to and in compliance with this Section 4.6, the transferee or successor (as the case may be) shall, subject to compliance with the terms of
Section 10.3, be admitted to the Partnership as the General Partner immediately prior to the transfer of the Partnership Interest, and the business of the Partnership shall continue without dissolution.

SECTION 4.7 Transfer of Incentive Distribution Rights. Prior to October 31, 2008, a holder of Incentive Distribution Rights may transfer any or all of the Incentive Distribution Rights held by such holder without any consent of the Unitholders (a) to an Affiliate of such holder (other than an individual) or (b) to another Person (other than an individual) in connection with (i) the merger or consolidation of such holder of Incentive Distribution Rights with or into such other Person or (ii) the transfer by such holder of all or substantially all of its assets to such other Person or (iii) the sale of all or substantially all of the equity interests of such holder to such other Person. Any other transfer of the Incentive Distribution Rights prior to October 31, 2008, shall require the prior approval of holders of at least a majority of the Outstanding Common Units (excluding Common Units held by the General Partner and its Affiliates). On or after October 31, 2008, any holder of Incentive Distribution Rights may transfer any or all of its Incentive Distribution Rights without Unitholder approval. Notwithstanding anything herein to the contrary, no transfer of Incentive Distribution Rights to another Person shall be permitted unless the transferee agrees to be bound by the provisions of this Agreement.

SECTION 4.8 Restrictions on Transfers.

(a) Except as provided in Section 4.8(d) below, but notwithstanding the other provisions of this Article IV, no transfer of any Partnership Interests shall be made if such transfer would (i) violate the then applicable federal or state securities laws or rules and regulations of the Commission, any state securities commission or any other governmental authority with jurisdiction over such transfer, (ii) terminate the existence or qualification of the Partnership or the Operating Partnership under the laws of the jurisdiction of its formation, or (iii) cause the Partnership or the Operating Partnership to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not already so treated or taxed).

(b) The General Partner may impose restrictions on the transfer of Partnership Interests if a subsequent Opinion of Counsel determines that such restrictions are necessary to avoid a significant risk of the Partnership or the Operating Partnership becoming an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes. The restrictions may be imposed by making such amendments to this Agreement as the General Partner may determine to be necessary or appropriate to impose such restrictions; provided,

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however, that any amendment that the General Partner believes, in the exercise of its reasonable discretion, could result in the delisting or suspension of trading of any class of Limited Partner Interests on the principal National Securities Exchange on which such class of Limited Partner Interests is then traded must be approved, prior to such amendment being effected, by the holders of at least a majority of the Outstanding Limited Partner Interests of such class.

(c) [RESERVED]

(d) Nothing contained in this Article IV, or elsewhere in this Agreement, shall preclude the settlement of any transactions involving Partnership Interests entered into through the facilities of any National Securities Exchange on which such Partnership Interests are listed for trading.

SECTION 4.9 Citizenship Certificates; Non-citizen Assignees.

(a) If any Group Member is or becomes subject to any federal, state or local law or regulation that, in the reasonable determination of the General Partner, creates a substantial risk of cancellation or forfeiture of any property in which the Group Member has an interest based on the nationality, citizenship or other related status of a Limited Partner or Assignee, the General Partner may request any Limited Partner or Assignee to furnish to the General Partner, within 30 days after receipt of such request, an executed Citizenship Certification or such other information concerning his nationality, citizenship or other related status (or, if the Limited Partner or Assignee is a nominee holding for the account of another Person, the nationality, citizenship or other related status of such Person) as the General Partner may request. If a Limited Partner or Assignee fails to furnish to the General Partner within the aforementioned 30-day period such Citizenship Certification or other requested information or if upon receipt of such Citizenship Certification or other requested information the General Partner determines, with the advice of counsel, that a Limited Partner or Assignee is not an Eligible Citizen, the Partnership Interests owned by such Limited Partner or Assignee shall be subject to redemption in accordance with the provisions of Section 4.10. In addition, the General Partner may require that the status of any such Partner or Assignee be changed to that of a Non-citizen Assignee and, thereupon, the General Partner shall be substituted for such Non-citizen Assignee as the Limited Partner in respect of his Limited Partner Interests.

(b) The General Partner shall, in exercising voting rights in respect of Limited Partner Interests held by it on behalf of Non-citizen Assignees, distribute the votes in the same ratios as the votes of Partners (including without limitation the General Partner) in respect of Limited Partner Interests other than those of Non-citizen Assignees are cast, either for, against or abstaining as to the matter.

(c) Upon dissolution of the Partnership, a Non-citizen Assignee shall have no right to receive a distribution in kind pursuant to Section 12.4 but shall be entitled to the cash equivalent thereof, and the Partnership shall provide cash in exchange for an assignment of the Non-citizen Assignee's share of the distribution in kind. Such payment and assignment shall be treated for Partnership purposes as a purchase by the Partnership from the Non-citizen Assignee of his Limited Partner Interest (representing his right to receive his share of such distribution in kind).

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(d) At any time after he can and does certify that he has become an Eligible Citizen, a Non-citizen Assignee may, upon application to the General Partner, request admission as a Substituted Limited Partner with respect to any Limited Partner Interests of such Non-citizen Assignee not redeemed pursuant to
Section 4.10, and upon his admission pursuant to Section 10.2, the General Partner shall cease to be deemed to be the Limited Partner in respect of the Non-citizen Assignee's Limited Partner Interests.

SECTION 4.10 Redemption of Partnership Interests of Non-citizen Assignees.

(a) If at any time a Limited Partner or Assignee fails to furnish a Citizenship Certification or other information requested within the 30-day period specified in Section 4.9(a), or if upon receipt of such Citizenship Certification or other information the General Partner determines, with the advice of counsel, that a Limited Partner or Assignee is not an Eligible Citizen, the Partnership may, unless the Limited Partner or Assignee establishes to the satisfaction of the General Partner that such Limited Partner or Assignee is an Eligible Citizen or has transferred his Partnership Interests to a Person who is an Eligible Citizen and who furnishes a Citizenship Certification to the General Partner prior to the date fixed for redemption as provided below, redeem the Partnership Interest of such Limited Partner or Assignee as follows:

(i) The General Partner shall, not later than the 30th day before the date fixed for redemption, give notice of redemption to the Limited Partner or Assignee, at his last address designated on the records of the Partnership or the Transfer Agent, by registered or certified mail, postage prepaid. The notice shall be deemed to have been given when so mailed. The notice shall specify the Redeemable Interests, the date fixed for redemption, the place of payment, that payment of the redemption price will be made upon surrender of the Certificate evidencing the Redeemable Interests and that on and after the date fixed for redemption no further allocations or distributions to which the Limited Partner or Assignee would otherwise be entitled in respect of the Redeemable Interests will accrue or be made.

(ii) The aggregate redemption price for Redeemable Interests shall be an amount equal to the Current Market Price (the date of determination of which shall be the date fixed for redemption) of Limited Partner Interests of the class to be so redeemed multiplied by the number of Limited Partner Interests of each such class included among the Redeemable Interests. The redemption price shall be paid, in the discretion of the General Partner, in cash or by delivery of a promissory note of the Partnership in the principal amount of the redemption price, bearing interest at the rate of 10% annually and payable in three equal annual installments of principal together with accrued interest, commencing one year after the redemption date.

(iii) Upon surrender by or on behalf of the Limited Partner or Assignee, at the place specified in the notice of redemption, of the Certificate evidencing the Redeemable Interests, duly endorsed in blank or accompanied by an assignment duly executed in blank, the Limited Partner or Assignee or his duly authorized representative shall be entitled to receive the payment therefor.

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(iv) After the redemption date, Redeemable Interests shall no longer constitute issued and Outstanding Limited Partner Interests.

(b) The provisions of this Section 4.10 shall also be applicable to Limited Partner Interests held by a Limited Partner or Assignee as nominee of a Person determined to be other than an Eligible Citizen.

(c) Nothing in this Section 4.10 shall prevent the recipient of a notice of redemption from transferring his Limited Partner Interest before the redemption date if such transfer is otherwise permitted under this Agreement. Upon receipt of notice of such a transfer, the General Partner shall withdraw the notice of redemption, provided the transferee of such Limited Partner Interest certifies to the satisfaction of the General Partner in a Citizenship Certification delivered in connection with the Transfer Application that he is an Eligible Citizen. If the transferee fails to make such certification, such redemption shall be effected from the transferee on the original redemption date.

ARTICLE V

CAPITAL CONTRIBUTIONS AND ISSUANCE OF PARTNERSHIP INTERESTS

SECTION 5.1 Organizational Contributions. In connection with the formation of the Partnership under the Delaware Act, the General Partner purchased a 2% General Partner Interest in the Partnership for $20.00 and has been admitted as a General Partner of the Partnership, and the Organizational Limited Partner purchased Common Units representing a 98% Limited Partner Interest in the Partnership for $980.00 and has been admitted as a Limited Partner of the Partnership. As of the Closing Date, the Organizational Limited Partner shall cease to be a Limited Partner of the Partnership.

SECTION 5.2 Contributions by the General Partner and its Affiliates.

(a) On or prior to the Closing Date and pursuant to the Contribution Agreement, (i) the General Partner shall convey to the Partnership, $1,000.00 in exchange for the Incentive Distribution Rights, and (ii) the Organizational Limited Partner shall contribute to the Partnership its limited partner interest in the Operating Partnership as a Capital Contribution.

(b) Upon the issuance of any additional Limited Partner Interests by the Partnership, the General Partner shall be required to make additional Capital Contributions equal to 2/98ths of any amount contributed to the Partnership by the Limited Partners in exchange for such additional Limited Partner Interests. Except as set forth in the immediately preceding sentence and Article XII, the General Partner shall not be obligated to make any additional Capital Contributions to the Partnership.

SECTION 5.3 Contributions by Initial Limited Partners and Distributions to the General Partner.

(a) [RESERVED]

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(b) [RESERVED]

(c) [RESERVED]

SECTION 5.4 Interest and Withdrawal. No interest shall be paid by the Partnership on Capital Contributions. No Partner or Assignee shall be entitled to the withdrawal or return of its Capital Contribution, except to the extent, if any, that distributions made pursuant to this Agreement or upon termination of the Partnership may be considered as such by law and then only to the extent provided for in this Agreement. Except to the extent expressly provided in this Agreement, no Partner or Assignee shall have priority over any other Partner or Assignee either as to the return of Capital Contributions or as to profits, losses or distributions. Any such return shall be a compromise to which all Partners and Assignees agree within the meaning of Section 17-502(b) of the Delaware Act.

SECTION 5.5 Capital Accounts.

(a) The Partnership shall maintain for each Partner (or a beneficial owner of Partnership Interests held by a nominee in any case in which the nominee has furnished the identity of such owner to the Partnership in accordance with Section 6031(c) of the Code or any other method acceptable to the General Partner in its sole discretion) owning a Partnership Interest a separate Capital Account with respect to such Partnership Interest in accordance with the rules of Treasury Regulation Section 1.704-1(b)(2)(iv). Such Capital Account shall be increased by (i) the amount of all Capital Contributions made to the Partnership with respect to such Partnership Interest pursuant to this Agreement and (ii) all items of Partnership income and gain (including, without limitation, income and gain exempt from tax) computed in accordance with Section 5.5(b) and allocated with respect to such Partnership Interest pursuant to
Section 6.1, and decreased by (x) the amount of cash or Net Agreed Value of all actual and deemed distributions of cash or property made with respect to such Partnership Interest pursuant to this Agreement and (y) all items of Partnership deduction and loss computed in accordance with Section 5.5(b) and allocated with respect to such Partnership Interest pursuant to Section 6.1.

(b) For purposes of computing the amount of any item of income, gain, loss or deduction which is to be allocated pursuant to Article VI and is to be reflected in the Partners' Capital Accounts, the determination, recognition and classification of any such item shall be the same as its determination, recognition and classification for federal income tax purposes (including, without limitation, any method of depreciation, cost recovery or amortization used for that purpose), provided, that:

(i) Solely for purposes of this Section 5.5, the Partnership shall be treated as owning directly its proportionate share (as determined by the General Partner based upon the provisions of the Operating Partnership Agreement) of all property owned by the Operating Partnership or any other Subsidiary that is classified as a partnership for federal income tax purposes.

(ii) All fees and other expenses incurred by the Partnership to promote the sale of (or to sell) a Partnership Interest that can neither be deducted nor amortized under

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Section 709 of the Code, if any, shall, for purposes of Capital Account maintenance, be treated as an item of deduction at the time such fees and other expenses are incurred and shall be allocated among the Partners pursuant to Section 6.1.

(iii) Except as otherwise provided in Treasury Regulation Section 1.704-1(b)(2)(iv)(m), the computation of all items of income, gain, loss and deduction shall be made without regard to any election under
Section 754 of the Code which may be made by the Partnership and, as to those items described in Section 705(a)(1)(B) or 705(a)(2)(B) of the Code, without regard to the fact that such items are not includable in gross income or are neither currently deductible nor capitalized for federal income tax purposes. To the extent an adjustment to the adjusted tax basis of any Partnership asset pursuant to Section 734(b) or 743(b) of the Code is required, pursuant to Treasury Regulation Section 1.704-1(b)(2)(iv)(m), to be taken into account in determining Capital Accounts, the amount of such adjustment in the Capital Accounts shall be treated as an item of gain or loss.

(iv) Any income, gain or loss attributable to the taxable disposition of any Partnership property shall be determined as if the adjusted basis of such property as of such date of disposition were equal in amount to the Partnership's Carrying Value with respect to such property as of such date.

(v) In accordance with the requirements of Section 704(b) of the Code, any deductions for depreciation, cost recovery or amortization attributable to any Contributed Property shall be determined as if the adjusted basis of such property on the date it was acquired by the Partnership were equal to the Agreed Value of such property. Upon an adjustment pursuant to Section 5.5(d) to the Carrying Value of any Partnership property subject to depreciation, cost recovery or amortization, any further deductions for such depreciation, cost recovery or amortization attributable to such property shall be determined (A) as if the adjusted basis of such property were equal to the Carrying Value of such property immediately following such adjustment and (B) using a rate of depreciation, cost recovery or amortization derived from the same method and useful life (or, if applicable, the remaining useful life) as is applied for federal income tax purposes; provided, however, that, if the asset has a zero adjusted basis for federal income tax purposes, depreciation, cost recovery or amortization deductions shall be determined using any reasonable method that the General Partner may adopt.

(vi) If the Partnership's adjusted basis in a depreciable or cost recovery property is reduced for federal income tax purposes pursuant to
Section 48(q)(1) or 48(q)(3) of the Code, the amount of such reduction shall, solely for purposes hereof, be deemed to be an additional depreciation or cost recovery deduction in the year such property is placed in service and shall be allocated among the Partners pursuant to Section 6.1. Any restoration of such basis pursuant to Section 48(q)(2) of the Code shall, to the extent possible, be allocated in the same manner to the

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Partners to whom such deemed deduction was allocated.

(c) (i) A transferee of a Partnership Interest shall succeed to a pro rata portion of the Capital Account of the transferor relating to the Partnership Interest so transferred.

(ii) [RESERVED]

(d) (i) In accordance with Treasury Regulation Section 1.704-1(b)(2)(iv)(f), on an issuance of additional Partnership Interests for cash or Contributed Property or the conversion of the General Partner's Combined Interest to Common Units pursuant to
Section 11.3(b), the Capital Account of all Partners and the Carrying Value of each Partnership property immediately prior to such issuance shall be adjusted upward or downward to reflect any Unrealized Gain or Unrealized Loss attributable to such Partnership property, as if such Unrealized Gain or Unrealized Loss had been recognized on an actual sale of each such property immediately prior to such issuance and had been allocated to the Partners at such time pursuant to Section 6.1 in the same manner as any item of gain or loss actually recognized during such period would have been allocated. In determining such Unrealized Gain or Unrealized Loss, the aggregate cash amount and fair market value of all Partnership assets (including, without limitation, cash or cash equivalents) immediately prior to the issuance of additional Partnership Interests shall be determined by the General Partner using such reasonable method of valuation as it may adopt; provided, however, that the General Partner, in arriving at such valuation, must take fully into account the fair market value of the Partnership Interests of all Partners at such time. The General Partner shall allocate such aggregate value among the assets of the Partnership (in such manner as it determines in its discretion to be reasonable) to arrive at a fair market value for individual properties.

(ii) In accordance with Treasury Regulation Section 1.704-1(b)(2)(iv)(f), immediately prior to any actual or deemed distribution to a Partner of any Partnership property (other than a distribution of cash that is not in redemption or retirement of a Partnership Interest), the Capital Accounts of all Partners and the Carrying Value of all Partnership property shall be adjusted upward or downward to reflect any Unrealized Gain or Unrealized Loss attributable to such Partnership property, as if such Unrealized Gain or Unrealized Loss had been recognized in a sale of such property immediately prior to such distribution for an amount equal to its fair market value, and had been allocated to the Partners, at such time, pursuant to Section 6.1 in the same manner as any item of gain or loss actually recognized during such period would have been allocated. In determining such Unrealized Gain or Unrealized Loss, the aggregate cash amount and fair market value of all Partnership assets (including, without limitation, cash or cash equivalents) immediately prior to a distribution shall (A) in the case of an actual distribution which is not made pursuant to Section 12.4 or in the case of a deemed distribution, be determined and allocated in the same manner as that provided in Section 5.5(d)(i) or (B) in the case of a liquidating distribution pursuant to Section

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12.4, be determined and allocated by the Liquidator using such reasonable method of valuation as it may adopt.

SECTION 5.6 Issuances of Additional Partnership Securities.

(a) Subject to Section 5.7, the Partnership may issue additional Partnership Securities and options, rights, warrants and appreciation rights relating to the Partnership Securities for any Partnership purpose at any time and from time to time to such Persons for such consideration and on such terms and conditions as shall be established by the General Partner in its sole discretion, all without the approval of any Limited Partners.

(b) Each additional Partnership Security authorized to be issued by the Partnership pursuant to Section 5.6(a) may be issued in one or more classes, or one or more series of any such classes, with such designations, preferences, rights, powers and duties (which may be senior to existing classes and series of Partnership Securities), as shall be fixed by the General Partner in the exercise of its sole discretion, including (i) the right to share Partnership profits and losses or items thereof; (ii) the right to share in Partnership distributions; (iii) rights upon dissolution and liquidation of the Partnership;
(iv) whether, and the terms and conditions upon which, the Partnership may redeem the Partnership Security; (v) whether such Partnership Security is issued with the privilege of conversion or exchange and, if so, the terms and conditions of such conversion or exchange; (vi) the terms and conditions upon which each Partnership Security will be issued, evidenced by certificates and assigned or transferred; and (vii) the right, if any, of each such Partnership Security to vote on Partnership matters, including matters relating to the relative rights, preferences and privileges of such Partnership Security.

(c) The General Partner is hereby authorized and directed to take all actions that it deems necessary or appropriate in connection with (i) each issuance of Partnership Securities and options (and the exercise thereof), rights (and the exercise thereof), warrants (and the exercise thereof) and appreciation rights relating to Partnership Securities pursuant to this Section 5.6, (ii) the conversion of the General Partner Interest or any Incentive Distribution Rights into Units pursuant to the terms of this Agreement, (iii) the admission of Additional Limited Partners and (iv) all additional issuances of Partnership Securities. The General Partner is further authorized and directed to specify the relative rights, powers and duties of the holders of the Units or other Partnership Securities being so issued. The General Partner shall do all things necessary to comply with the Delaware Act and is authorized and directed to do all things it deems to be necessary or advisable in connection with any future issuance of Partnership Securities or in connection with the conversion of the General Partner Interest or any Incentive Distribution Rights into Units pursuant to the terms of this Agreement, including compliance with any statute, rule, regulation or guideline of any federal, state or other governmental agency or any National Securities Exchange on which the Units or other Partnership Securities are listed for trading.

SECTION 5.7 Limitations on Issuance of Additional Partnership Securities. Except as otherwise specified in this Section 5.7, the issuance of Partnership Securities pursuant to Section 5.6 shall be subject to the following restrictions and limitations:

(a) No fractional Units shall be issued by the Partnership.

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SECTION 5.8 [RESERVED].

SECTION 5.9 Limited Preemptive Right. Except as provided in this Section 5.9 and in Section 5.2, no Person shall have any preemptive, preferential or other similar right with respect to the issuance of any Partnership Security, whether unissued, held in the treasury or hereafter created. The General Partner shall have the right, which it may from time to time assign in whole or in part to any of its Affiliates, to purchase Partnership Securities from the Partnership whenever, and on the same terms that, the Partnership issues Partnership Securities to Persons other than the General Partner and its Affiliates, to the extent necessary to maintain the Percentage Interests of the General Partner and its Affiliates equal to that which existed immediately prior to the issuance of such Partnership Securities.

SECTION 5.10 Splits and Combinations.

(a) Subject to Sections 5.10(d), 6.6 and 6.9 (dealing with adjustments of distribution levels), the Partnership may make a Pro Rata distribution of Partnership Securities to all Record Holders or may effect a subdivision or combination of Partnership Securities so long as, after any such event, each Partner shall have the same Percentage Interest in the Partnership as before such event, and any amounts calculated on a per Unit basis (including any Common Unit Arrearage or Cumulative Common Unit Arrearage) or stated as a number of Units are proportionately adjusted retroactive to the beginning of the Partnership.

(b) Whenever such a distribution, subdivision or combination of Partnership Securities is declared, the General Partner shall select a Record Date as of which the distribution, subdivision or combination shall be effective and shall send notice thereof at least 20 days prior to such Record Date to each Record Holder as of a date not less than 10 days prior to the date of such notice. The General Partner also may cause a firm of independent public accountants selected by it to calculate the number of Partnership Securities to be held by each Record Holder after giving effect to such distribution, subdivision or combination. The General Partner shall be entitled to rely on any certificate provided by such firm as conclusive evidence of the accuracy of such calculation.

(c) Promptly following any such distribution, subdivision or combination, the Partnership may issue Certificates to the Record Holders of Partnership Securities as of the applicable Record Date representing the new number of Partnership Securities held by such Record Holders, or the General Partner may adopt such other procedures as it may deem appropriate to reflect such changes. If any such combination results in a smaller total number of Partnership Securities Outstanding, the Partnership shall require, as a condition to the delivery to a Record Holder of such new Certificate, the surrender of any Certificate held by such Record Holder immediately prior to such Record Date.

(d) The Partnership shall not issue fractional Units upon any distribution, subdivision or combination of Units. If a distribution, subdivision or combination of Units would result in the issuance of fractional Units but for the provisions of Section 5.7(a) and this Section 5.10(d), each fractional Unit shall be rounded to the nearest whole Unit (and a 0.5 Unit shall be rounded to the next higher Unit).

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SECTION 5.11 Fully Paid and Non-Assessable Nature of Limited Partner Interests. All Limited Partner Interests issued pursuant to, and in accordance with the requirements of, this Article V shall be fully paid and non-assessable Limited Partner Interests in the Partnership, except as such non-accessibility may be affected by Section 17-607 of the Delaware Act.

ARTICLE VI

ALLOCATIONS AND DISTRIBUTIONS

SECTION 6.1 Allocations for Capital Account Purposes. For purposes of maintaining the Capital Accounts and in determining the rights of the Partners among themselves, the Partnership's items of income, gain, loss and deduction (computed in accordance with Section 5.5(b)) shall be allocated among the Partners in each taxable year (or portion thereof) as provided herein below.

(a) Net Income. After giving effect to the special allocations set forth in Section 6.1(d), Net Income for each taxable year and all items of income, gain, loss and deduction taken into account in computing Net Income for such taxable year shall be allocated as follows:

(i) First, 100% to the General Partner, in an amount equal to the aggregate Net Losses allocated to the General Partner pursuant to
Section 6.1(b)(iii) for all previous taxable years until the aggregate Net Income allocated to the General Partner pursuant to this Section 6.1(a)(i) for the current taxable year and all previous taxable years is equal to the aggregate Net Losses allocated to the General Partner pursuant to Section 6.1(b)(iii) for all previous taxable years;

(ii) Second, 2% to the General Partner, in an amount equal to the aggregate Net Losses allocated to the General Partner pursuant to Section 6.1(b)(ii) for all previous taxable years and 98% to the Unitholders, in accordance with their respective Percentage Interests, until the aggregate Net Income allocated to such Partners pursuant to this
Section 6.1(a)(ii) for the current taxable year and all previous taxable years is equal to the aggregate Net Losses allocated to such Partners pursuant to Section 6.1(b)(ii) for all previous taxable years; and

(iii) Third, 2% to the General Partner, and 98% to the Unitholders, Pro Rata.

(b) Net Losses. After giving effect to the special allocations set forth in Section 6.1(d), Net Losses for each taxable period and all items of income, gain, loss and deduction taken into account in computing Net Losses for such taxable period shall be allocated as follows:

(i) First, 2% to the General Partner, and 98% to the Unitholders, Pro Rata, until the aggregate Net Losses allocated pursuant to this
Section 6.1(b)(i) for the current taxable year and all previous taxable years is equal to the aggregate Net Income allocated to such Partners pursuant to Section 6.1(a)(iii) for all previous taxable years, provided that the Net Losses shall not be allocated pursuant to this Section 6.1(b)(i) to the extent that such allocation would cause any Unitholder to have a

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deficit balance in its Adjusted Capital Account at the end of such taxable year (or increase any existing deficit balance in its Adjusted Capital Account);

(ii) Second, 2% to the General Partner, and 98% to the Unitholders, Pro Rata; provided, that Net Losses shall not be allocated pursuant to this Section 6.1(b)(ii) to the extent that such allocation would cause any Unitholder to have a deficit balance in its Adjusted Capital Account at the end of such taxable year (or increase any existing deficit balance in its Adjusted Capital Account);

(iii) Third, the balance, if any, 100% to the General Partner.

(c) Net Termination Gains and Losses. After giving effect to the special allocations set forth in Section 6.1(d), all items of income, gain, loss and deduction taken into account in computing Net Termination Gain or Net Termination Loss for such taxable period shall be allocated in the same manner as such Net Termination Gain or Net Termination Loss is allocated hereunder. All allocations under this Section 6.1(c) shall be made after Capital Account balances have been adjusted by all other allocations provided under this Section 6.1 and after all distributions of Available Cash provided under Sections 6.4 and 6.5 have been made; provided, however, that solely for purposes of this
Section 6.1(c), Capital Accounts shall not be adjusted for distributions made pursuant to Section 12.4.

(i) If a Net Termination Gain is recognized (or deemed recognized pursuant to Section 5.5(d)), such Net Termination Gain shall be allocated among the Partners in the following manner (and the Capital Accounts of the Partners shall be increased by the amount so allocated in each of the following subclauses, in the order listed, before an allocation is made pursuant to the next succeeding subclause):

(A) First, to each Partner having a deficit balance in its Capital Account, in the proportion that such deficit balance bears to the total deficit balances in the Capital Accounts of all Partners, until each such Partner has been allocated Net Termination Gain equal to any such deficit balance in its Capital Account;

(B) Second, 98% to all Unitholders holding Common Units, Pro Rata, and 2% to the General Partner, until the Capital Account in respect of each Common Unit then Outstanding is equal to the sum of (1) its Unrecovered Capital plus (2) the Minimum Quarterly Distribution for the Quarter during which the Liquidation Date occurs, reduced by any distribution pursuant to Section 6.4(a)(i) with respect to such Common Unit for such Quarter (the amount determined pursuant to this clause (2) is hereinafter defined as the "Unpaid MQD") plus (3) any then existing Cumulative Common Unit Arrearage;

(C) Third, 98% to all Unitholders, Pro Rata, and 2% to the General Partner, until the Capital Account in respect of each Common Unit then

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Outstanding is equal to the sum of (1) its Unrecovered Capital, plus (2) the Unpaid MQD, plus (3) any then existing Cumulative Common Unit Arrearage, plus (4) the excess of (aa) the First Target Distribution less the Minimum Quarterly Distribution for each Quarter of the Partnership's existence over (bb) the cumulative per Unit amount of any distributions of Available Cash that is deemed to be Operating Surplus made pursuant to Section
6.4(a)(iii) (the sum of (1) plus (2) plus (3) plus (4) is hereinafter defined as the "First Liquidation Target Amount");

(D) Fourth, 85% to all Unitholders, Pro Rata, 13% to the holders of the Incentive Distribution Rights, Pro Rata, and 2% to the General Partner, until the Capital Account in respect of each Common Unit then Outstanding is equal to the sum of (1) the First Liquidation Target Amount, plus (2) the excess of (aa) the Second Target Distribution less the First Target Distribution for each Quarter of the Partnership's existence over (bb) the cumulative per Unit amount of any distributions of Available Cash that is deemed to be Operating Surplus made pursuant to Section
6.4(a)(iv) (the sum of (1) plus (2) is hereinafter defined as the "Second Liquidation Target Amount");

(E) Fifth, 75% to all Unitholders, Pro Rata, 23% to the holders of the Incentive Distribution Rights, Pro Rata, and 2% to the General Partner, until the Capital Account in respect of each Common Unit then Outstanding is equal to the sum of (1) the Second Liquidation Target Amount, plus (2) the excess of (aa) the Third Target Distribution less the Second Target Distribution for each Quarter of the Partnership's existence over (bb) the cumulative per Unit amount of any distributions of Available Cash that is deemed to be Operating Surplus made pursuant to Section
6.4(a)(v) (the sum of (1) plus (2) is hereinafter defined as the "Third Liquidation Target Amount"); and

(F) Finally, any remaining amount 50% to all Unitholders, Pro Rata, 48% to the holders of the Incentive Distribution Rights, Pro Rata, and 2% to the General Partner.

(ii) If a Net Termination Loss is recognized (or deemed recognized pursuant to Section 5.5(d)), such Net Termination Loss shall be allocated among the Partners in the following manner:

(A) First, 98% to all Unitholders holding Common Units, Pro Rata, and 2% to the General Partner, until the Capital Account in respect of each Common Unit then Outstanding has been reduced to zero; and

(B) Second, the balance, if any, 100% to the General Partner.

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(d) Special Allocations. Notwithstanding any other provision of this Section 6.1, the following special allocations shall be made for such taxable period:

(i) Partnership Minimum Gain Chargeback. Notwithstanding any other provision of this Section 6.1, if there is a net decrease in Partnership Minimum Gain during any Partnership taxable period, each Partner shall be allocated items of Partnership income and gain for such period (and, if necessary, subsequent periods) in the manner and amounts provided in Treasury Regulation Sections 1.704-2(f)(6), 1.704-2(g)(2) and 1.704-2(j)(2)(i), or any successor provision. For purposes of this Section 6.1(d), each Partner's Adjusted Capital Account balance shall be determined, and the allocation of income or gain required hereunder shall be effected, prior to the application of any other allocations pursuant to this Section 6.1(d) with respect to such taxable period (other than an allocation pursuant to Sections 6.1(d)(vi) and 6.1(d)(vii)). This Section 6.1(d)(i) is intended to comply with the Partnership Minimum Gain chargeback requirement in Treasury Regulation Section 1.704-2(f) and shall be interpreted consistently therewith.

(ii) Chargeback of Partner Nonrecourse Debt Minimum Gain. Notwithstanding the other provisions of this Section 6.1 (other than Section 6.1(d)(i)), except as provided in Treasury Regulation Section 1.704-2(i)(4), if there is a net decrease in Partner Nonrecourse Debt Minimum Gain during any Partnership taxable period, any Partner with a share of Partner Nonrecourse Debt Minimum Gain at the beginning of such taxable period shall be allocated items of Partnership income and gain for such period (and, if necessary, subsequent periods) in the manner and amounts provided in Treasury Regulation Sections 1.704-2(i)(4) and 1.704-2(j)(2)(ii), or any successor provisions. For purposes of this Section 6.1(d), each Partner's Adjusted Capital Account balance shall be determined, and the allocation of income or gain required hereunder shall be effected, prior to the application of any other allocations pursuant to this Section 6.1(d), other than
Section 6.1(d)(i) and other than an allocation pursuant to Sections 6.1(d)(vi) and 6.1(d)(vii), with respect to such taxable period. This Section 6.1(d)(ii) is intended to comply with the chargeback of items of income and gain requirement in Treasury Regulation Section 1.704-2(i)(4) and shall be interpreted consistently therewith.

(iii) Priority Allocations.

(A) If the amount of cash or the Net Agreed Value of any property distributed (except cash or property distributed pursuant to
Section 12.4) to any Unitholder with respect to its Units for a taxable year is greater (on a per

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Unit basis) than the amount of cash or the Net Agreed Value of property distributed to the other Unitholders with respect to their Units (on a per Unit basis), then (1) each Unitholder receiving such greater cash or property distribution shall be allocated gross income in an amount equal to the product of (aa) the amount by which the distribution (on a per Unit basis) to such Unitholder exceeds the distribution (on a per Unit basis) to the Unitholders receiving the smallest distribution and (bb) the number of Units owned by the Unitholder receiving the greater distribution; and (2) the General Partner shall be allocated gross income in an aggregate amount equal to 1/98th of the sum of the amounts allocated in clause (1) above.

(B) After the application of Section 6.1(d)(iii)(A), all or any portion of the remaining items of Partnership gross income or gain for the taxable period, if any, shall be allocated 100% to the holders of Incentive Distribution Rights, Pro Rata, until the aggregate amount of such items allocated to the holders of Incentive Distribution Rights pursuant to this paragraph 6.1(d)(iii)(B) for the current taxable year and all previous taxable years is equal to the cumulative amount of all Incentive Distributions made to the holders of Incentive Distribution Rights from the Closing Date to a date 45 days after the end of the current taxable year.

(iv) Qualified Income Offset. Notwithstanding the other provisions of this Section 6.1 (other than Sections 6.1(d)(i) and (d)(ii)), in the event any Partner unexpectedly receives any adjustments, allocations or distributions described in Treasury Regulation Sections 1.704-1(b)(2)(ii)(d)(4), 704-1(b)(2)(ii)(d)(5), or 1.704-1(b)(2)(ii)(d)(6), items of Partnership income and gain shall be specially allocated to such Partner in an amount and manner sufficient to eliminate, to the extent required by the Treasury Regulations promulgated under Section 704(b) of the Code, the deficit balance, if any, in its Adjusted Capital Account created by such adjustments, allocations or distributions as quickly as possible unless such deficit balance is otherwise eliminated pursuant to Section 6.1(d)(i) or (ii).

(v) Gross Income Allocations. In the event any Partner has a deficit balance in its Capital Account at the end of any Partnership taxable period in excess of the sum of (A) the amount such Partner is required to restore pursuant to the provisions of this Agreement and (B) the amount such Partner is deemed obligated to restore pursuant to Treasury Regulation Sections 1.704-2(g) and 1.704-2(i)(5), such Partner shall be specially allocated items of Partnership gross income and gain in the amount of such excess as quickly as possible; provided, that an allocation pursuant to this Section 6.1(d)(v) shall be made only if and to the extent that such Partner would have a deficit balance in its Capital Account as adjusted after all other allocations provided for in this Section 6.1 have been tentatively made as if this Section 6.1(d)(v) were not in this Agreement.

(vi) Nonrecourse Deductions. Nonrecourse Deductions for any taxable period shall be allocated to the Partners in accordance with their respective Percentage Interests. If the General Partner determines in its good faith discretion that the Partnership's

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Nonrecourse Deductions must be allocated in a different ratio to satisfy the safe harbor requirements of the Treasury Regulations promulgated under Section 704(b) of the Code, the General Partner is authorized, upon notice to the other Partners, to revise the prescribed ratio to the numerically closest ratio that does satisfy such requirements.

(vii) Partner Nonrecourse Deductions. Partner Nonrecourse Deductions for any taxable period shall be allocated 100% to the Partner that bears the Economic Risk of Loss with respect to the Partner Nonrecourse Debt to which such Partner Nonrecourse Deductions are attributable in accordance with Treasury Regulation Section 1.704-2(i). If more than one Partner bears the Economic Risk of Loss with respect to a Partner Nonrecourse Debt, such Partner Nonrecourse Deductions attributable thereto shall be allocated between or among such Partners in accordance with the ratios in which they share such Economic Risk of Loss.

(viii) Nonrecourse Liabilities. For purposes of Treasury Regulation Section 1.752-3(a)(3), the Partners agree that Nonrecourse Liabilities of the Partnership in excess of the sum of (A) the amount of Partnership Minimum Gain and (B) the total amount of Nonrecourse Built-in Gain shall be allocated among the Partners in accordance with their respective Percentage Interests.

(ix) Code Section 754 Adjustments. To the extent an adjustment to the adjusted tax basis of any Partnership asset pursuant to Section 734(b) or 743(c) of the Code is required, pursuant to Treasury Regulation
Section 1.704-1(b)(2)(iv)(m), to be taken into account in determining Capital Accounts, the amount of such adjustment to the Capital Accounts shall be treated as an item of gain (if the adjustment increases the basis of the asset) or loss (if the adjustment decreases such basis), and such item of gain or loss shall be specially allocated to the Partners in a manner consistent with the manner in which their Capital Accounts are required to be adjusted pursuant to such Section of the Treasury Regulations.

(x) Curative Allocation.

(A) Notwithstanding any other provision of this Section 6.1, other than the Required Allocations, the Required Allocations shall be taken into account in making the Agreed Allocations so that, to the extent possible, the net amount of items of income, gain, loss and deduction allocated to each Partner pursuant to the Required Allocations and the Agreed Allocations, together, shall be equal to the net amount of such items that would have been allocated to each such Partner under the Agreed Allocations had the Required Allocations and the related Curative Allocation not otherwise been provided in this Section 6.1. Notwithstanding the preceding sentence, Required Allocations relating to (1) Nonrecourse Deductions shall not be taken into account except to the extent that there

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has been a decrease in Partnership Minimum Gain and (2) Partner Nonrecourse Deductions shall not be taken into account except to the extent that there has been a decrease in Partner Nonrecourse Debt Minimum Gain. Allocations pursuant to this Section 6.1(d)(x)(A) shall only be made with respect to Required Allocations to the extent the General Partner reasonably determines that such allocations will otherwise be inconsistent with the economic agreement among the Partners. Further, allocations pursuant to this Section 6.1(d)(x)(A) shall be deferred with respect to allocations pursuant to clauses (1) and
(2) hereof to the extent the General Partner reasonably determines that such allocations are likely to be offset by subsequent Required Allocations.

(B) The General Partner shall have reasonable discretion, with respect to each taxable period, to (1) apply the provisions of
Section 6.1(d)(x)(A) in whatever order is most likely to minimize the economic distortions that might otherwise result from the Required Allocations, and (2) divide all allocations pursuant to
Section 6.1(d)(x)(A) among the Partners in a manner that is likely to minimize such economic distortions.

(xi) Corrective Allocations. In the event of any allocation of Additional Book Basis Derivative Items or any Book-Down Event or any recognition of a Net Termination Loss, the following rules shall apply:

(A) In the case of any allocation of Additional Book Basis Derivative Items (other than an allocation of Unrealized Gain or Unrealized Loss under Section 5.5(d) hereof), the General Partner shall allocate additional items of gross income and gain away from the holders of Incentive Distribution Rights to the Unitholders and the General Partner, or additional items of deduction and loss away from the Unitholders and the General Partner to the holders of Incentive Distribution Rights, to the extent that the Additional Book Basis Derivative Items allocated to the Unitholders or the General Partner exceed their Share of Additional Book Basis Derivative Items. For this purpose, the Unitholders and the General Partner shall be treated as being allocated Additional Book Basis Derivative Items to the extent that such Additional Book Basis Derivative Items have reduced the amount of income that would otherwise have been allocated to the Unitholders or the General Partner under the Partnership Agreement (e.g., Additional Book Basis Derivative Items taken into account in computing cost of goods sold would reduce the amount of book income otherwise available for allocation among the Partners). Any allocation made pursuant to this Section 6.1(d)(xi)(A) shall be made after all of the other Agreed Allocations have been made as if this Section 6.1(d)(xi) were not in this Agreement and, to the extent necessary, shall require the reallocation of items that have been allocated pursuant to such other Agreed Allocations.

(B) In the case of any negative adjustments to the Capital Accounts of the Partners resulting from a Book-Down Event or from the recognition of a

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Net Termination Loss, such negative adjustment (1) shall first be allocated, to the extent of the Aggregate Remaining Net Positive Adjustments, in such a manner, as reasonably determined by the General Partner, that to the extent possible the aggregate Capital Accounts of the Partners will equal the amount which would have been the Capital Account balance of the Partners if no prior Book-Up Events had occurred, and (2) any negative adjustment in excess of the Aggregate Remaining Net Positive Adjustments shall be allocated pursuant to Section 6.1(c) hereof.

(C) In making the allocations required under this Section 6.1(d)(xi), the General Partner, in its sole discretion, may apply whatever conventions or other methodology it deems reasonable to satisfy the purpose of this Section 6.1(d)(xi).

SECTION 6.2 Allocations for Tax Purposes.

(a) Except as otherwise provided herein, for federal income tax purposes, each item of income, gain, loss and deduction shall be allocated among the Partners in the same manner as its correlative item of "book" income, gain, loss or deduction is allocated pursuant to Section 6.1.

(b) In an attempt to eliminate Book-Tax Disparities attributable to a Contributed Property or Adjusted Property, items of income, gain, loss, depreciation, amortization and cost recovery deductions shall be allocated for federal income tax purposes among the Partners as follows:

(i) (A) In the case of a Contributed Property, such items attributable thereto shall be allocated among the Partners in the manner provided under Section 704(c) of the Code that takes into account the variation between the Agreed Value of such property and its adjusted basis at the time of contribution; and (B) any item of Residual Gain or Residual Loss attributable to a Contributed Property shall be allocated among the Partners in the same manner as its correlative item of "book" gain or loss is allocated pursuant to Section 6.1.

(ii) (A) In the case of an Adjusted Property, such items shall (1) first, be allocated among the Partners in a manner consistent with the principles of Section 704(c) of the Code to take into account the Unrealized Gain or Unrealized Loss attributable to such property and the allocations thereof pursuant to Section 5.5(d)(i) or 5.5(d)(ii), and (2) second, in the event such property was originally a Contributed Property, be allocated among the Partners in a manner consistent with Section 6.2(b)(i)(A); and (B) any item of Residual Gain or Residual Loss attributable to an Adjusted Property shall be allocated among the Partners in the same manner as its correlative item of "book" gain or loss is allocated pursuant to Section 6.1.

(iii) The General Partner shall apply the principles of Treasury Regulation
Section 1.704-3(d) to eliminate Book-Tax Disparities.

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(c) For the proper administration of the Partnership and for the preservation of uniformity of the Limited Partner Interests (or any class or classes thereof), the General Partner shall have sole discretion to (i) adopt such conventions as it deems appropriate in determining the amount of depreciation, amortization and cost recovery deductions; (ii) make special allocations for federal income tax purposes of income (including, without limitation, gross income) or deductions; and (iii) amend the provisions of this Agreement as appropriate (x) to reflect the proposal or promulgation of Treasury Regulations under Section 704(b) or Section 704(c) of the Code (including without limitation Treasury Regulations regarding compensatory and noncompensatory options) or (y) otherwise to preserve or achieve uniformity of the Limited Partner Interests (or any class or classes thereof). The General Partner may adopt such conventions, make such allocations and make such amendments to this Agreement as provided in this Section 6.2(c) only if such conventions, allocations or amendments would not have a material adverse effect on the Partners, the holders of any class or classes of Limited Partner Interests issued and Outstanding or the Partnership, and if such allocations are consistent with the principles of Section 704 of the Code. Additionally, the General partner has the authority to amend the provisions of this Agreement as necessary to conform to proposed or promulgated Treasury Regulations under Subchapter K of the Code regarding compensatory and noncompensatory options to acquire a Partnership Security.

(d) The General Partner in its discretion may determine to depreciate or amortize the portion of an adjustment under Section 743(b) of the Code attributable to unrealized appreciation in any Adjusted Property (to the extent of the unamortized Book-Tax Disparity) using a predetermined rate derived from the depreciation or amortization method and useful life applied to the Partnership's common basis of such property, despite any inconsistency of such approach with Treasury Regulation Section 1.167(c)-l(a)(6) or any successor regulations thereto. If the General Partner determines that such reporting position cannot reasonably be taken, the General Partner may adopt depreciation and amortization conventions under which all purchasers acquiring Limited Partner Interests in the same month would receive depreciation and amortization deductions, based upon the same applicable rate as if they had purchased a direct interest in the Partnership's property. If the General Partner chooses not to utilize such aggregate method, the General Partner may use any other reasonable depreciation and amortization conventions to preserve the uniformity of the intrinsic tax characteristics of any Limited Partner Interests that would not have a material adverse effect on the Limited Partners or the Record Holders of any class or classes of Limited Partner Interests.

(e) Any gain allocated to the Partners upon the sale or other taxable disposition of any Partnership asset shall, to the extent possible, after taking into account other required allocations of gain pursuant to this Section 6.2, be characterized as Recapture Income in the same proportions and to the same extent as such Partners (or their predecessors in interest) have been allocated any deductions directly or indirectly giving rise to the treatment of such gains as Recapture Income.

(f) All items of income, gain, loss, deduction and credit recognized by the Partnership for federal income tax purposes and allocated to the Partners in accordance with the provisions hereof shall be determined without regard to any election under Section 754 of the Code which may be made by the Partnership; provided, however, that such allocations, once

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made, shall be adjusted as necessary or appropriate to take into account those adjustments permitted or required by Sections 734 and 743 of the Code.

(g) Each item of Partnership income, gain, loss and deduction shall for federal income tax purposes, be determined on an annual basis and prorated on a monthly basis and shall be allocated to the Partners as of the opening of the Nasdaq National Market on the first Business Day of each month; provided, however, that gain or loss on a sale or other disposition of any assets of the Partnership or any other extraordinary item of income or loss realized and recognized other than in the ordinary course of business, as determined by the General Partner in its sole discretion, shall be allocated to the Partners as of the opening of the Nasdaq National Market on the first Business Day of the month in which such gain or loss is recognized for federal income tax purposes. The General Partner may revise, alter or otherwise modify such methods of allocation as it determines necessary or appropriate in its sole discretion, to the extent permitted or required by Section 706 of the Code and the regulations or rulings promulgated thereunder.

(h) Allocations that would otherwise be made to a Limited Partner under the provisions of this Article VI shall instead be made to the beneficial owner of Limited Partner Interests held by a nominee in any case in which the nominee has furnished the identity of such owner to the Partnership in accordance with
Section 6031(c) of the Code or any other method acceptable to the General Partner in its sole discretion.

SECTION 6.3 Requirement and Characterization of Distributions; Distributions to Record Holders.

(a) Within 45 days following the end of each Quarter, an amount equal to 100% of Available Cash with respect to such Quarter shall, subject to Section 17-607 of the Delaware Act, be distributed in accordance with this Article VI by the Partnership to the Partners as of the Record Date selected by the General Partner in its reasonable discretion. All amounts of Available Cash distributed by the Partnership on any date from any source shall be deemed to be Operating Surplus until the sum of all amounts of Available Cash theretofore distributed by the Partnership to the Partners pursuant to Section 6.4 equals the Operating Surplus from the Closing Date through the close of the immediately preceding Quarter. Any remaining amounts of Available Cash distributed by the Partnership on such date shall, except as otherwise provided in Section 6.5, be deemed to be "Capital Surplus." All distributions required to be made under this Agreement shall be made subject to Section 17-607 of the Delaware Act.

(b) Notwithstanding Section 6.3(a), in the event of the dissolution and liquidation of the Partnership, all receipts received during or after the Quarter in which the Liquidation Date occurs, other than from borrowings described in (a)(ii) of the definition of Available Cash, shall be applied and distributed solely in accordance with, and subject to the terms and conditions of, Section 12.4.

(c) The General Partner shall have the discretion to treat taxes paid by the Partnership on behalf of, or amounts withheld with respect to, all or less than all of the Partners, as a distribution of Available Cash to such Partners.

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(d) Each distribution in respect of a Partnership Interest shall be paid by the Partnership, directly or through the Transfer Agent or through any other Person or agent, only to the Record Holder of such Partnership Interest as of the Record Date set for such distribution. Such payment shall constitute full payment and satisfaction of the Partnership's liability in respect of such payment, regardless of any claim of any Person who may have an interest in such payment by reason of an assignment or otherwise.

SECTION 6.4 Distributions of Available Cash from Operating Surplus.

(a) Available Cash with respect to any Quarter that is deemed to be Operating Surplus pursuant to the provisions of Section 6.3 or 6.5, subject to
Section 17-607 of the Delaware Act, shall be distributed as follows, except as otherwise required by Section 5.6(b) in respect of additional Partnership Securities issued pursuant thereto:

(i) First, 98% to all Unitholders, Pro Rata, and 2% to the General Partner, until there has been distributed in respect of each Unit then Outstanding an amount equal to the Minimum Quarterly Distribution for such Quarter;

(ii) Second, 98% to the Unitholders, Pro Rata, and 2% to the General Partner, until there has been distributed in respect of each Common Unit then Outstanding an amount equal to the Cumulative Common Unit Arrearage existing with respect to such Quarter;

(iii) Third, 98% to all Unitholders, Pro Rata, and 2% to the General Partner, until there has been distributed in respect of each Unit then Outstanding an amount equal to the excess of the First Target Distribution over the Minimum Quarterly Distribution for such Quarter;

(iv) Fourth, 85% to all Unitholders, Pro Rata, 13% to the holders of the Incentive Distribution Rights, Pro Rata, and 2% to the General Partner, until there has been distributed in respect of each Unit then Outstanding an amount equal to the excess of the Second Target Distribution over the First Target Distribution for such Quarter;

(v) Fifth, 75% to all Unitholders, Pro Rata, 23% to the holders of the Incentive Distribution Rights, Pro Rata, and 2% to the General Partner, until there has been distributed in respect of each Unit then Outstanding an amount equal to the excess of the Third Target Distribution over the Second Target Distribution for such Quarter; and

(vi) Thereafter, 50% to all Unitholders, Pro Rata, 48% to the holders of the Incentive Distribution Rights, Pro Rata, and 2% to the General Partner;

provided, however, if the Minimum Quarterly Distribution, the First Target Distribution, the Second Target Distribution and the Third Target Distribution have been reduced to zero pursuant to the second sentence of Section 6.6(a), the distribution of Available Cash that is deemed to be

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Operating Surplus with respect to any Quarter will be made solely in accordance with Section 6.4(a)(vi).

SECTION 6.5 Distributions of Available Cash from Capital Surplus. Available Cash that is deemed to be Capital Surplus pursuant to the provisions of Section 6.3(a) shall, subject to Section 17-607 of the Delaware Act, be distributed, unless the provisions of Section 6.3 require otherwise, 98% to all Unitholders, Pro Rata, and 2% to the General Partner, until a hypothetical holder of an Initial Common Unit has received with respect to such Common Unit, during the period since the Closing Date through such date, distributions of Available Cash that are deemed to be Capital Surplus in an aggregate amount equal to the Initial Unit Capital Account. Available Cash that is deemed to be Capital Surplus shall then be distributed 98% to all Unitholders holding Common Units, Pro Rata, and 2% to the General Partner, until there has been distributed in respect of each Common Unit then Outstanding an amount equal to the Cumulative Common Unit Arrearage. Thereafter, all Available Cash shall be distributed as if it were Operating Surplus and shall be distributed in accordance with Section 6.4.

SECTION 6.6 Adjustment of Minimum Quarterly Distribution and Target Distribution Levels.

(a) The Minimum Quarterly Distribution, First Target Distribution, Second Target Distribution, Third Target Distribution, Common Unit Arrearages and Cumulative Common Unit Arrearages shall be proportionately adjusted in the event of any distribution, combination or subdivision (whether effected by a distribution payable in Units or otherwise) of Units or other Partnership Securities in accordance with Section 5.10. In the event of a distribution of Available Cash that is deemed to be from Capital Surplus, the then applicable Minimum Quarterly Distribution, First Target Distribution, Second Target Distribution and Third Target Distribution, shall be adjusted proportionately downward to equal the product obtained by multiplying the otherwise applicable Minimum Quarterly Distribution, First Target Distribution, Second Target Distribution and Third Target Distribution, as the case may be, by a fraction of which the numerator is the Unrecovered Capital of the Common Units immediately after giving effect to such distribution and of which the denominator is the Unrecovered Capital of the Common Units immediately prior to giving effect to such distribution.

(b) The Minimum Quarterly Distribution, First Target Distribution, Second Target Distribution and Third Target Distribution, shall also be subject to adjustment pursuant to Section 6.9.

SECTION 6.7 [RESERVED].

SECTION 6.8 Special Provisions Relating to the Holders of Incentive Distribution Rights. Notwithstanding anything to the contrary set forth in this Agreement, the holders of the Incentive Distribution Rights (a) shall (i) possess the rights and obligations provided in this Agreement with respect to a Limited Partner pursuant to Articles III and VII and (ii) have a Capital Account as a Partner pursuant to Section 5.5 and all other provisions related thereto and (b) shall not (i) be entitled to vote on any matters requiring the approval or vote of the holders of Outstanding Units, (ii) be entitled to any distributions other than as provided in Sections

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6.4(a)(iv) through (vi), and 12.4 or (iii) be allocated items of income, gain, loss or deduction other than as specified in this Article VI.

SECTION 6.9 Entity-Level Taxation. If legislation is enacted or the interpretation of existing language is modified by the relevant governmental authority which causes a Group Member to be treated as an association taxable as a corporation or otherwise subjects a Group Member to entity-level taxation for federal, state or local income tax purposes, the then applicable Minimum Quarterly Distribution, First Target Distribution, Second Target Distribution and Third Target Distribution, shall be adjusted to equal the product obtained by multiplying (a) the amount thereof by (b) one minus the sum of (i) the highest marginal federal corporate (or other entity, as applicable) income tax rate of the Group Member for the taxable year of the Group Member in which such Quarter occurs (expressed as a percentage) plus (ii) the effective overall state and local income tax rate (expressed as a percentage) applicable to the Group Member for the calendar year next preceding the calendar year in which such Quarter occurs (after taking into account the benefit of any deduction allowable for federal income tax purposes with respect to the payment of state and local income taxes), but only to the extent of the increase in such rates resulting from such legislation or interpretation. Such effective overall state and local income tax rate shall be determined for the taxable year next preceding the first taxable year during which the Group Member is taxable for federal income tax purposes as an association taxable as a corporation or is otherwise subject to entity-level taxation by determining such rate as if the Group Member had been subject to such state and local taxes during such preceding taxable year.

ARTICLE VII

MANAGEMENT AND OPERATION OF BUSINESS

SECTION 7.1 Management.

(a) The General Partner shall conduct, direct and manage all activities of the Partnership. Except as otherwise expressly provided in this Agreement, all management powers over the business and affairs of the Partnership shall be exclusively vested in the General Partner, and no Limited Partner or Assignee shall have any management power over the business and affairs of the Partnership. In addition to the powers now or hereafter granted a general partner of a limited partnership under applicable law or which are granted to the General Partner under any other provision of this Agreement, the General Partner, subject to Section 7.3, shall have full power and authority to do all things and on such terms as it, in its sole discretion, may deem necessary or appropriate to conduct the business of the Partnership, to exercise all powers set forth in Section 2.5 and to effectuate the purposes set forth in Section 2.4, including the following:

(i) the making of any expenditures, the lending or borrowing of money, the assumption or guarantee of, or other contracting for, indebtedness and other liabilities, the issuance of evidences of indebtedness, including indebtedness that is convertible into Partnership Securities, and the incurring of any other obligations;

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(ii) the making of tax, regulatory and other filings, or rendering of periodic or other reports to governmental or other agencies having jurisdiction over the business or assets of the Partnership;

(iii) the acquisition, disposition, mortgage, pledge, encumbrance, hypothecation or exchange of any or all of the assets of the Partnership or the merger or other combination of the Partnership with or into another Person (the matters described in this clause (iii) being subject, however, to any prior approval that may be required by
Section 7.3);

(iv) the use of the assets of the Partnership (including cash on hand) for any purpose consistent with the terms of this Agreement, including the financing of the conduct of the operations of the Partnership Group; subject to Section 7.6(a), the lending of funds to other Persons (including other Group Members), the repayment or guarantee of obligations of the Partnership Group and the making of capital contributions to any member of the Partnership Group;

(v) the negotiation, execution and performance of any contracts, conveyances or other instruments (including instruments that limit the liability of the Partnership under contractual arrangements to all or particular assets of the Partnership, with the other party to the contract to have no recourse against the General Partner or its assets other than its interest in the Partnership, even if same results in the terms of the transaction being less favorable to the Partnership than would otherwise be the case);

(vi) the distribution of Partnership cash;

(vii) the selection and dismissal of employees (including employees having titles such as "president," "vice president," "secretary" and "treasurer") and agents, outside attorneys, accountants, consultants and contractors and the determination of their compensation and other terms of employment or hiring;

(viii) the maintenance of such insurance for the benefit of the Partnership Group and the Partners as it deems necessary or appropriate;

(ix) the formation of, or acquisition of an interest in, and the contribution of property and the making of loans to, any other limited or general partnerships, joint ventures, corporations, limited liability companies or other relationships (including the acquisition of interests in, and the contributions of property to, any Group Member from time to time) subject to the restrictions set forth in
Section 2.4;

(x) the control of any matters affecting the rights and obligations of the Partnership, including the bringing and defending of actions at law or in equity and otherwise engaging in the conduct of litigation and the incurring of legal expense and the settlement of claims and litigation;

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(xi) the indemnification of any Person against liabilities and contingencies to the extent permitted by law;

(xii) the entering into of listing agreements with any National Securities Exchange and the delisting of some or all of the Limited Partner Interests from, or requesting that trading be suspended on, any such exchange (subject to any prior approval that may be required under
Section 4.8);

(xiii) unless restricted or prohibited by Section 5.7, the purchase, sale or other acquisition or disposition of Partnership Securities, or the issuance of additional options, rights, warrants and appreciation rights relating to Partnership Securities; and

(xiv) the undertaking of any action in connection with the Partnership's participation in the Operating Partnership or any other subsidiary of the Partnership as a member or partner.

(b) Notwithstanding any other provision of this Agreement, the Operating Partnership Agreement, the Delaware Act or any applicable law, rule or regulation, each of the Partners and the Assignees and each other Person who may acquire an interest in Partnership Securities hereby (i) approves, ratifies and confirms the execution, delivery and performance by the parties thereto of the Operating Partnership Agreement, the Omnibus Agreement, the Contribution Agreement, the Distribution Agreement, and the Purchase Contract dated October 1, 2004, between Penn Octane Corporation and the Operating Partnership and the other agreements described in or filed as exhibits to the Registration Statement that are related to the transactions contemplated by the Registration Statement;
(ii) agrees that the General Partner (on its own or through any officer of the Partnership) is authorized to execute, deliver and perform the agreements referred to in clause (i) of this sentence and the other agreements, acts, transactions and matters described in or contemplated by the Registration Statement on behalf of the Partnership without any further act, approval or vote of the Partners or the Assignees or the other Persons who may acquire an interest in Partnership Securities; and (iii) agrees that the execution, delivery or performance by the General Partner, any Group Member or any Affiliate of any of them, of this Agreement or any agreement authorized or permitted under this Agreement (including the exercise by the General Partner or any Affiliate of the General Partner of the rights accorded pursuant to Article
XV), shall not constitute a breach by the General Partner of any duty that the General Partner may owe the Partnership or the Limited Partners or any other Persons under this Agreement (or any other agreements) or of any duty stated or implied by law or equity.

SECTION 7.2 Certificate of Limited Partnership. The General Partner has caused the Certificate of Limited Partnership to be filed with the Secretary of State of the State of Delaware as required by the Delaware Act. The General Partner shall use all reasonable efforts to cause to be filed such other certificates or documents as may be determined by the General Partner in its sole discretion to be reasonable and necessary or appropriate for the formation, continuation, qualification and operation of a limited partnership (or a partnership in which the limited partners have limited liability) in the State of Delaware or any other state in which the Partnership may

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elect to do business or own property. To the extent that such action is determined by the General Partner in its sole discretion to be reasonable and necessary or appropriate, the General Partner shall file amendments to and restatements of the Certificate of Limited Partnership and do all things to maintain the Partnership as a limited partnership (or a partnership or other entity in which the limited partners have limited liability) under the laws of the State of Delaware or of any other state in which the Partnership may elect to do business or own property. Subject to the terms of Section 3.4(a), the General Partner shall not be required, before or after filing, to deliver or mail a copy of the Certificate of Limited Partnership, any qualification document or any amendment thereto to any Limited Partner.

SECTION 7.3 Restrictions on the General Partner's Authority.

(a) The General Partner may not, without written approval of the specific act by holders of all of the Outstanding Limited Partner Interests or by other written instrument executed and delivered by holders of all of the Outstanding Limited Partner Interests subsequent to the date of this Agreement, take any action in contravention of this Agreement, including, except as otherwise provided in this Agreement, (i) committing any act that would make it impossible to carry on the ordinary business of the Partnership; (ii) possessing Partnership property, or assigning any rights in specific Partnership property, for other than a Partnership purpose; (iii) admitting a Person as a Partner;
(iv) amending this Agreement in any manner; or (v) transferring its interest as a general partner of the Partnership.

(b) Except as provided in Articles XII and XIV, the General Partner may not sell, exchange or otherwise dispose of all or substantially all of the Partnership's assets in a single transaction or a series of related transactions (including by way of merger, consolidation or other combination) or approve on behalf of the Partnership the sale, exchange or other disposition of all or substantially all of the assets of the Operating Partnership without the approval of holders of a Unit Majority; provided however that this provision shall not preclude or limit the General Partner's ability to mortgage, pledge, hypothecate or grant a security interest in all or substantially all of the assets of the Partnership or the Operating Partnership and shall not apply to any forced sale of any or all of the assets of the Partnership or the Operating Partnership pursuant to the foreclosure of, or other realization upon, any such encumbrance. Without the approval of holders of a Unit Majority, the General Partner shall not, on behalf of the Partnership, (i) consent to any amendment to the Operating Partnership Agreement or (ii) except as expressly permitted by
Section 7.9(d), take any action permitted to be taken by a partner of the Operating Partnership, in either case, that would adversely affect the Limited Partners (including any particular class of Partnership Interests as compared to any other class of Partnership Interests) in any material respect, except, in either case, as permitted under Sections 4.6, 11.1 and 11.2 with respect to the election of a successor general partner or managing member of any Group Member.

SECTION 7.4 Reimbursement of the General Partner.

(a) Except as provided in this Section 7.4 and elsewhere in this Agreement, the General Partner shall not be compensated for its services as a general partner or managing member of any Group Member.

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(b) The General Partner shall be reimbursed on a monthly basis, or such other reasonable basis as the General Partner may determine in its sole discretion, for (i) all direct and indirect expenses it incurs or payments it makes on behalf of the Partnership (including salary, bonus, incentive compensation and other amounts paid to any Person including Affiliates of the General Partner to perform services for the Partnership or for the General Partner in the discharge of its duties to the Partnership), and (ii) all other necessary or appropriate expenses allocable to the Partnership or otherwise reasonably incurred by the General Partner in connection with operating the Partnership's business (including expenses allocated to the General Partner by its Affiliates). The General Partner shall determine the expenses that are allocable to the Partnership in any reasonable manner determined by the General Partner in its sole discretion. Reimbursements pursuant to this Section 7.4 shall be in addition to any reimbursement to the General Partner as a result of indemnification pursuant to Section 7.7.

(c) Subject to Section 5.7, the General Partner, in its sole discretion and without the approval of the Limited Partners (who shall have no right to vote in respect thereof), may propose and adopt on behalf of the Partnership employee benefit plans, employee programs and employee practices (including plans, programs and practices involving the issuance of Partnership Securities or options to purchase Partnership Securities), or cause the Partnership to issue Partnership Securities in connection with, or pursuant to, any employee benefit plan, employee program or employee practice maintained or sponsored by the General Partner or any of its Affiliates, in each case for the benefit of employees of the General Partner, any Group Member or any Affiliate, or any of them, in respect of services performed, directly or indirectly, for the benefit of the Partnership Group. The Partnership agrees to issue and sell to the General Partner or any of its Affiliates any Partnership Securities that the General Partner or such Affiliates are obligated to provide to any employees pursuant to any such employee benefit plans, employee programs or employee practices. Expenses incurred by the General Partner in connection with any such plans, programs and practices (including the net cost to the General Partner or such Affiliates of Partnership Securities purchased by the General Partner or such Affiliates from the Partnership to fulfill options or awards under such plans, programs and practices) shall be reimbursed in accordance with Section
7.4(b). Any and all obligations of the General Partner under any employee benefit plans, employee programs or employee practices adopted by the General Partner as permitted by this Section 7.4(c) shall constitute obligations of the General Partner hereunder and shall be assumed by any successor General Partner approved pursuant to Section 11.1 or 11.2 or the transferee of or successor to all of the General Partner's General Partner Interest pursuant to Section 4.6.

SECTION 7.5 Outside Activities.

(a) After the Closing Date, the General Partner, for so long as it is the General Partner of the Partnership agrees that its sole business will be to act as a general partner or managing member, as the case may be, of the Partnership and any other partnership or limited liability company of which the Partnership or the Operating Partnership is, directly or indirectly, a partner or member and to undertake activities that are ancillary or related thereto (including being a limited partner in the Partnership).

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(b) Penn Octane Corporation has entered into the Omnibus Agreement with the General Partner, and the Partnership, which agreement sets forth certain aspects of the business relationship between Penn Octane Corporation and its Affiliates and the Partnership.

(c) Each Indemnitee (other than the General Partner) shall have the right to engage in businesses of every type and description and other activities for profit and to engage in and possess an interest in other business ventures of any and every type or description, whether in businesses engaged in or anticipated to be engaged in by any Group Member, independently or with others, including business interests and activities in direct competition with the business and activities of any Group Member, and none of the same shall constitute a breach of this Agreement or any duty express or implied by law to any Group Member or any Partner or Assignee. Neither any Group Member, any Limited Partner nor any other Person shall have any rights by virtue of this Agreement, the Operating Partnership Agreement, the limited liability company or partnership agreement of any other Group Member or the partnership relationship established hereby or thereby in any business ventures of any Indemnitee.

(d) Notwithstanding anything to the contrary in this Agreement, (i) the engaging in competitive activities by any Indemnitees (other than the General Partner) in accordance with the provisions of this Section 7.5 is hereby approved by the Partnership and all Partners, (ii) it shall be deemed not to be a breach of the General Partner's fiduciary duty or any other obligation of any type whatsoever of the General Partner for the Indemnitees (other than the General Partner) to engage in such business interests and activities in preference to or to the exclusion of the Partnership and (iii) Penn Octane Corporation, the General Partner and the Indemnitees shall have no obligation to present business opportunities to the Partnership.

(e) The General Partner and any of its Affiliates may acquire Units or other Partnership Securities in addition to those acquired on the Closing Date and, except as otherwise provided in this Agreement, shall be entitled to exercise all rights of the General Partner or Limited Partner, as applicable, relating to such Units or Partnership Securities.

(f) The term "Affiliates" when used in Section 7.5(a) and Section 7.5(e) with respect to the General Partner shall not include any Group Member or any Subsidiary of the Group Member.

(g) Anything in this Agreement to the contrary notwithstanding, to the extent that provisions of Sections 7.7, 7.8, 7.9, 7.10 or other Sections of this Agreement purport or are interpreted to have the effect of restricting the fiduciary duties that might otherwise, as a result of Delaware or other applicable law, be owed by the General Partner to the Partnership and its Limited Partners, or to constitute a waiver or consent by the Limited Partners to any such restriction, such provisions shall be inapplicable and have no effect in determining whether the General Partner has complied with its fiduciary duties in connection with determinations made by it under this Section 7.5.

SECTION 7.6 Loans from the General Partner; Loans or Contributions from the Partnership; Contracts with Affiliates; Certain Restrictions on the General
Partner.

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(a) The General Partner or any of its Affiliates may lend to any Group Member, and any Group Member may borrow from the General Partner or any of its Affiliates, funds needed or desired by the Group Member for such periods of time and in such amounts as the General Partner may determine; provided, however, that in any such case the lending party may not charge the borrowing party interest at a rate greater than the rate that would be charged the borrowing party or impose terms less favorable to the borrowing party than would be charged or imposed on the borrowing party by unrelated lenders on comparable loans made on an arm's-length basis (without reference to the lending party's financial abilities or guarantees). The borrowing party shall reimburse the lending party for any costs (other than any additional interest costs) incurred by the lending party in connection with the borrowing of such funds. For purposes of this Section 7.6(a) and Section 7.6(b), the term "Group Member" shall include any Affiliate of a Group Member that is controlled by the Group Member. No Group Member may lend funds to the General Partner or any of its Affiliates (other than another Group Member).

(b) The Partnership may lend or contribute to any Group Member, and any Group Member may borrow from the Partnership, funds on terms and conditions established in the sole discretion of the General Partner; provided, however, that the Partnership may not charge the Group Member interest at a rate less than the rate that would be charged to the Group Member (without reference to the General Partner's financial abilities or guarantees) by unrelated lenders on comparable loans. The foregoing authority shall be exercised by the General Partner in its sole discretion and shall not create any right or benefit in favor of any Group Member or any other Person.

(c) The General Partner may itself, or may enter into an agreement with any of its Affiliates to, render services to a Group Member or to the General Partner in the discharge of its duties as General Partner of the Partnership. Any services rendered to a Group Member by the General Partner or any of its Affiliates shall be on terms that are fair and reasonable to the Partnership; provided, however, that the requirements of this Section 7.6(c) shall be deemed satisfied as to (i) any transaction approved by Special Approval, (ii) any transaction, the terms of which are no less favorable to the Partnership Group than those generally being provided to or available from unrelated third parties or (iii) any transaction that, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to the Partnership Group), is equitable to the Partnership Group. The provisions of Section 7.4 shall apply to the rendering of services described in this Section 7.6(c).

(d) The Partnership Group may transfer assets to joint ventures, other partnerships, corporations, limited liability companies or other business entities in which it is or thereby becomes a participant upon such terms and subject to such conditions as are consistent with this Agreement and applicable law.

(e) Neither the General Partner nor any of its Affiliates shall sell, transfer or convey any property to, or purchase any property from, the Partnership, directly or indirectly, except pursuant to transactions that are fair and reasonable to the Partnership; provided, however, that the requirements of this Section 7.6(e) shall be deemed to be satisfied as to (i) the transactions effected pursuant to Sections 5.2 and 5.3, the Contribution Agreement and any other transactions

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described in or contemplated by the Registration Statement, (ii) any transaction approved by Special Approval, (iii) any transaction, the terms of which are no less favorable to the Partnership than those generally being provided to or available from unrelated third parties, or (iv) any transaction that, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to the Partnership), is equitable to the Partnership. With respect to any contribution of assets to the Partnership in exchange for Partnership Securities, the Conflicts Committee, in determining whether the appropriate number of Partnership Securities are being issued, may take into account, among other things, the fair market value of the assets, the liquidated and contingent liabilities assumed, the tax basis in the assets, the extent to which tax-only allocations to the transferor will protect the existing partners of the Partnership against a low tax basis, and such other factors as the Conflicts Committee deems relevant under the circumstances.

(f) The General Partner and its Affiliates will have no obligation to permit any Group Member to use any facilities or assets of the General Partner and its Affiliates, except as may be provided in contracts entered into from time to time specifically dealing with such use, nor shall there be any obligation on the part of the General Partner or its Affiliates to enter into such contracts.

(g) Without limitation of Sections 7.6(a) through 7.6(f), and notwithstanding anything to the contrary in this Agreement, the existence of the conflicts of interest described in the Registration Statement are hereby approved by all Partners.

SECTION 7.7 Indemnification.

(a) To the fullest extent permitted by law but subject to the limitations expressly provided in this Agreement, all Indemnitees shall be indemnified and held harmless by the Partnership from and against any and all losses, claims, damages, liabilities, joint or several, expenses (including legal fees and expenses), judgments, fines, penalties, interest, settlements or other amounts arising from any and all claims, demands, actions, suits or proceedings, whether civil, criminal, administrative or investigative, in which any Indemnitee may be involved, or is threatened to be involved, as a party or otherwise, by reason of its status as an Indemnitee; provided, that in each case the Indemnitee acted in good faith and in a manner that such Indemnitee reasonably believed to be in, or (in the case of a Person other than the General Partner) not opposed to, the best interests of the Partnership and, with respect to any criminal proceeding, had no reasonable cause to believe its conduct was unlawful; provided, further, no indemnification pursuant to this Section 7.7 shall be available to the General Partner with respect to its obligations incurred pursuant to the Omnibus Agreement, the Contribution Agreement and the Distribution Agreement (other than obligations incurred by the General Partner on behalf of the Partnership). The termination of any action, suit or proceeding by judgment, order, settlement, conviction or upon a plea of nolo contendere, or its equivalent, shall not create a presumption that the Indemnitee acted in a manner contrary to that specified above. Any indemnification pursuant to this
Section 7.7 shall be made only out of the assets of the Partnership, it being agreed that the General Partner shall not be personally liable for such indemnification and shall have no obligation to contribute or loan any monies or property to the Partnership to enable it to effectuate such indemnification.

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(b) To the fullest extent permitted by law, expenses (including legal fees and expenses) incurred by an Indemnitee who is indemnified pursuant to
Section 7.7(a) in defending any claim, demand, action, suit or proceeding shall, from time to time, be advanced by the Partnership prior to the final disposition of such claim, demand, action, suit or proceeding upon receipt by the Partnership of any undertaking by or on behalf of the Indemnitee to repay such amount if it shall be determined that the Indemnitee is not entitled to be indemnified as authorized in this Section 7.7.

(c) The indemnification provided by this Section 7.7 shall be in addition to any other rights to which an Indemnitee may be entitled under any agreement, pursuant to any vote of the holders of Outstanding Limited Partner Interests, as a matter of law or otherwise, both as to actions in the Indemnitee's capacity as an Indemnitee and as to actions in any other capacity, and shall continue as to an Indemnitee who has ceased to serve in such capacity and shall inure to the benefit of the heirs, successors, assigns and administrators of the Indemnitee.

(d) The Partnership may purchase and maintain (or reimburse the General Partner or its Affiliates for the cost of) insurance, on behalf of the General Partner, its Affiliates and such other Persons as the General Partner shall determine, against any liability that may be asserted against or expense that may be incurred by such Person in connection with the Partnership's activities or such Person's activities on behalf of the Partnership, regardless of whether the Partnership would have the power to indemnify such Person against such liability under the provisions of this Agreement.

(e) For purposes of this Section 7.7, the Partnership shall be deemed to have requested an Indemnitee to serve as fiduciary of an employee benefit plan whenever the performance by it of its duties to the Partnership also imposes duties on, or otherwise involves services by, it to the plan or participants or beneficiaries of the plan; excise taxes assessed on an Indemnitee with respect to an employee benefit plan pursuant to applicable law shall constitute "fines" within the meaning of Section 7.7(a); and action taken or omitted by it with respect to any employee benefit plan in the performance of its duties for a purpose reasonably believed by it to be in the interest of the participants and beneficiaries of the plan shall be deemed to be for a purpose which is in, or not opposed to, the best interests of the Partnership.

(f) In no event may an Indemnitee subject the Limited Partners to personal liability by reason of the indemnification provisions set forth in this Agreement.

(g) An Indemnitee shall not be denied indemnification in whole or in part under this Section 7.7 because the Indemnitee had an interest in the transaction with respect to which the indemnification applies if the transaction was otherwise permitted by the terms of this Agreement.

(h) The provisions of this Section 7.7 are for the benefit of the Indemnitees, their heirs, successors, assigns and administrators and shall not be deemed to create any rights for the benefit of any other Persons.

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(i) No amendment, modification or repeal of this Section 7.7 or any provision hereof shall in any manner terminate, reduce or impair the right of any past, present or future Indemnitee to be indemnified by the Partnership, nor the obligations of the Partnership to indemnify any such Indemnitee under and in accordance with the provisions of this Section 7.7 as in effect immediately prior to such amendment, modification or repeal with respect to claims arising from or relating to matters occurring, in whole or in part, prior to such amendment, modification or repeal, regardless of when such claims may arise or be asserted.

SECTION 7.8 Liability of Indemnitees.

(a) Notwithstanding anything to the contrary set forth in this Agreement, no Indemnitee shall be liable for monetary damages to the Partnership, the Limited Partners, the Assignees or any other Persons who have acquired interests in the Partnership Securities, for losses sustained or liabilities incurred as a result of any act or omission if such Indemnitee acted in good faith.

(b) Subject to its obligations and duties as General Partner set forth in Section 7.1(a), the General Partner may exercise any of the powers granted to it by this Agreement and perform any of the duties imposed upon it hereunder either directly or by or through its agents, and the General Partner shall not be responsible for any misconduct or negligence on the part of any such agent appointed by the General Partner in good faith.

(c) To the extent that, at law or in equity, an Indemnitee has duties (including fiduciary duties) and liabilities relating thereto to the Partnership or to the Partners, the General Partner and any other Indemnitee acting in connection with the Partnership's business or affairs shall not be liable to the Partnership or to any Partner for its good faith reliance on the provisions of this Agreement. The provisions of this Agreement, to the extent that they restrict or otherwise modify the duties and liabilities of an Indemnitee otherwise existing at law or in equity, are agreed by the Partners to replace such other duties and liabilities of such Indemnitee.

(d) Any amendment, modification or repeal of this Section 7.8 or any provision hereof shall be prospective only and shall not in any way affect the limitations on the liability to the Partnership, the Limited Partners, the General Partner, and the Partnership's and General Partner's directors, officers and employees under this Section 7.8 as in effect immediately prior to such amendment, modification or repeal with respect to claims arising from or relating to matters occurring, in whole or in part, prior to such amendment, modification or repeal, regardless of when such claims may arise or be asserted.

SECTION 7.9 Resolution of Conflicts of Interest.

(a) Unless otherwise expressly provided in this Agreement, the Operating Partnership Agreement or the limited liability company agreement or partnership agreement of any other Group Member, whenever a potential conflict of interest exists or arises between the General Partner or any of its Affiliates, on the one hand, and the Partnership, the Operating Partnership, any other Group Member, any Partner or any Assignee, on the other, any resolution or course of action by the General Partner or its Affiliates in respect of such conflict of interest shall be

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permitted and deemed approved by all Partners, and shall not constitute a breach of this Agreement, of the Operating Partnership Agreement, of any agreement contemplated herein or therein, or of any duty stated or implied by law or equity, if the resolution or course of action is, or by operation of this Agreement is deemed to be, fair and reasonable to the Partnership. The General Partner shall be required in connection with its resolution of such conflict of interest to seek Special Approval of such resolution. Any such approval by the Conflicts Committee shall be subject to the presumption that, in making its decision, the Conflicts Committee acted on an informed basis, in good faith, and in the honest belief that the action taken was in the best interests of the Partnership, and in any proceeding brought by any Unitholder or by or on behalf of such Unitholder or any other Unitholders or the Partnership challenging such approval, the Person bringing or prosecuting such proceeding shall have the burden of overcoming such presumption. Any conflict of interest and any resolution of such conflict of interest shall be conclusively deemed fair and reasonable to the Partnership if such conflict of interest or resolution is (i) approved by Special Approval, (ii) on terms no less favorable to the Partnership than those generally being provided to or available from unrelated third parties or (iii) fair to the Partnership, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to the Partnership). The General Partner (including the Conflicts Committee in connection with Special Approval) shall be authorized in connection with its determination of what is "fair and reasonable" to the Partnership and in connection with its resolution of any conflict of interest to consider (A) the relative interests of any party to such conflict, agreement, transaction or situation and the benefits and burdens relating to such interest; (B) any customary or accepted industry practices and any customary or historical dealings with a particular Person; (C) any applicable generally accepted accounting practices or principles; and (D) such additional factors as the General Partner (including the Conflicts Committee) determines in its sole discretion to be relevant, reasonable or appropriate under the circumstances. In any proceeding brought by any Unitholder by or on behalf of such Unitholder or any other Unitholders or the Partnership alleging that such a resolution by the General Partner (and not by the Conflicts Committee, whose resolution shall be conclusive as provided above) is not fair to the Partnership, such Unitholder shall have the burden of proof of overcoming such conclusion. Nothing contained in this Agreement, however, is intended to nor shall it be construed to require the General Partner (including the Conflicts Committee) to consider the interests of any Person other than the Partnership. In the absence of bad faith by the General Partner, the resolution, action or terms so made, taken or provided by the General Partner with respect to such matter shall not constitute a breach of this Agreement or any other agreement contemplated herein or a breach of any standard of care or duty imposed herein or therein or, to the extent permitted by law, under the Delaware Act or any other law, rule or regulation.

(b) Whenever this Agreement or any other agreement contemplated hereby provides that the General Partner or any of its Affiliates is permitted or required to make a decision (i) in its "sole discretion" or "discretion," that it deems "necessary or appropriate" or "necessary or advisable" or under a grant of similar authority or latitude, except as otherwise provided herein, the General Partner or such Affiliate shall be entitled to consider only such interests and factors as it desires and shall have no duty or obligation to give any consideration to any interest of, or factors affecting, the Partnership, the Operating Partnership, any Group Member, any Limited Partner or any Assignee,
(ii) it may make such decision in its sole discretion (regardless of

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whether there is a reference to "sole discretion" or "discretion") unless another express standard is provided for, or (iii) in "good faith" or under another express standard, the General Partner or such Affiliate shall act under such express standard and shall not be subject to any other or different standards imposed by this Agreement, the Operating Partnership Agreement, the limited liability company agreement or partnership agreement of any Group Member any other agreement contemplated hereby or under the Delaware Act or any other law, rule or regulation. In addition, any actions taken by the General Partner or such Affiliate consistent with the standards of "reasonable discretion" set forth in the definitions of Available Cash or Operating Surplus shall not constitute a breach of any duty of the General Partner to the Partnership or the Limited Partners. The General Partner shall have no duty, express or implied, to sell or otherwise dispose of any asset of the Partnership Group other than in the ordinary course of business. No borrowing by any Group Member or the approval thereof by the General Partner shall be deemed to constitute a breach of any duty of the General Partner to the Partnership or the Limited Partners by reason of the fact that the purpose or effect of such borrowing is directly or indirectly to enable distributions to the General Partner or its Affiliates (including in their capacities as Limited Partners) to exceed 2% of the total amount distributed to all partners.

(c) Whenever a particular transaction, arrangement or resolution of a conflict of interest is required under this Agreement to be "fair and reasonable" to any Person, the fair and reasonable nature of such transaction, arrangement or resolution shall be considered in the context of all similar or related transactions.

(d) The Unitholders hereby authorize the General Partner, on behalf of the Partnership as a partner or member of a Group Member, to approve of actions by the general partner or managing member of such Group Member similar to those actions permitted to be taken by the General Partner pursuant to this Section 7.9.

SECTION 7.10 Other Matters Concerning the General Partner.

(a) The General Partner may rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, bond, debenture or other paper or document believed by it to be genuine and to have been signed or presented by the proper party or parties.

(b) The General Partner may consult with legal counsel, accountants, appraisers, management consultants, investment bankers and other consultants and advisers selected by it, and any act taken or omitted to be taken in reliance upon the opinion (including an Opinion of Counsel) of such Persons as to matters that the General Partner reasonably believes to be within such Person's professional or expert competence shall be conclusively presumed to have been done or omitted in good faith and in accordance with such opinion.

(c) The General Partner shall have the right, in respect of any of its powers or obligations hereunder, to act through any of its duly authorized officers, a duly appointed attorney or attorneys-in-fact or the duly authorized officers of the Partnership.

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(d) Any standard of care and duty imposed by this Agreement or under the Delaware Act or any applicable law, rule or regulation shall be modified, waived or limited, to the extent permitted by law, as required to permit the General Partner to act under this Agreement or any other agreement contemplated by this Agreement and to make any decision pursuant to the authority prescribed in this Agreement, so long as such action is reasonably believed by the General Partner to be in, or not inconsistent with, the best interests of the Partnership.

SECTION 7.11 Purchase or Sale of Partnership Securities. The General Partner may cause the Partnership to purchase or otherwise acquire Partnership Securities. As long as Partnership Securities are held by any Group Member, such Partnership Securities shall not be considered Outstanding for any purpose, except as otherwise provided herein. The General Partner or any Affiliate of the General Partner may also purchase or otherwise acquire and sell or otherwise dispose of Partnership Securities for its own account, subject to the provisions of Articles IV and X.

SECTION 7.12 Registration Rights of the General Partner and its Affiliates.

(a) If (i) the General Partner or any Affiliate of the General Partner (including for purposes of this Section 7.12, any Person that is an Affiliate of the General Partner at the date of this Agreement notwithstanding that it may later cease to be an Affiliate of the General Partner) holds Partnership Securities that it desires to sell and (ii) Rule 144 of the Securities Act (or any successor rule or regulation to Rule 144) or another exemption from registration is not available to enable such holder of Partnership Securities (the "Holder") to dispose of the number of Partnership Securities it desires to sell at the time it desires to do so without registration under the Securities Act, then upon the request of any such Holder, the Partnership shall file with the Commission as promptly as practicable after receiving such request, and use all reasonable efforts to cause to become effective and remain effective for a period of not less than six months following its effective date or such shorter period as shall terminate when all Partnership Securities covered by such registration statement have been sold, a registration statement under the Securities Act registering the offering and sale of the number of Partnership Securities specified by the Holder; provided, however, that the Partnership shall not be required to effect more than three registrations pursuant to this
Section 7.12(a); and provided further, however, that if the Conflicts Committee determines in its good faith judgment that a postponement of the requested registration for up to six months would be in the best interests of the Partnership and its Partners due to a pending transaction, investigation or other event, the filing of such registration statement or the effectiveness thereof may be deferred for up to six months, but not thereafter. In connection with any registration pursuant to the immediately preceding sentence, the Partnership shall promptly prepare and file (x) such documents as may be necessary to register or qualify the securities subject to such registration under the securities laws of such states as the Holder shall reasonably request; provided, however, that no such qualification shall be required in any jurisdiction where, as a result thereof, the Partnership would become subject to general service of process or to taxation or qualification to do business as a foreign corporation or partnership doing business in such jurisdiction solely as a result of such registration, and (y) such documents as may be necessary to apply for listing or to list the Partnership Securities subject to such registration on such National Securities Exchange as the Holder shall reasonably request, and do any and all other acts and things that may reasonably be

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necessary or advisable to enable the Holder to consummate a public sale of such Partnership Securities in such states. Except as set forth in Section 7.12(c), all costs and expenses of any such registration and offering (other than the underwriting discounts and commissions) shall be paid by the Partnership, without reimbursement by the Holder.

(b) If the Partnership shall at any time propose to file a registration statement under the Securities Act for an offering of equity securities of the Partnership for cash (other than an offering relating solely to an employee benefit plan), the Partnership shall use all reasonable efforts to include such number or amount of securities held by the Holder in such registration statement as the Holder shall request. If the proposed offering pursuant to this Section 7.12(b) shall be an underwritten offering, then, in the event that the managing underwriter or managing underwriters of such offering advise the Partnership and the Holder in writing that in their opinion the inclusion of all or some of the Holder's Partnership Securities would adversely and materially affect the success of the offering, the Partnership shall include in such offering only that number or amount, if any, of securities held by the Holder which, in the opinion of the managing underwriter or managing underwriters, will not so adversely and materially affect the offering. Except as set forth in Section 7.12(c), all costs and expenses of any such registration and offering (other than the underwriting discounts and commissions) shall be paid by the Partnership, without reimbursement by the Holder.

(c) If underwriters are engaged in connection with any registration referred to in this Section 7.12, the Partnership shall provide indemnification, representations, covenants, opinions and other assurance to the underwriters in form and substance reasonably satisfactory to such underwriters. Further, in addition to and not in limitation of the Partnership's obligation under Section 7.7, the Partnership shall, to the fullest extent permitted by law, indemnify and hold harmless the Holder, its officers, directors and each Person who controls the Holder (within the meaning of the Securities Act) and any agent thereof (collectively, "Indemnified Persons") against any losses, claims, demands, actions, causes of action, assessments, damages, liabilities (joint or several), costs and expenses (including interest, penalties and reasonable attorneys' fees and disbursements), resulting to, imposed upon, or incurred by the Indemnified Persons, directly or indirectly, under the Securities Act or otherwise (hereinafter referred to in this Section 7.12(c) as a "claim" and in the plural as "claims") based upon, arising out of or resulting from any untrue statement or alleged untrue statement of any material fact contained in any registration statement under which any Partnership Securities were registered under the Securities Act or any state securities or Blue Sky laws, in any preliminary prospectus (if used prior to the effective date of such registration statement), or in any summary or final prospectus or in any amendment or supplement thereto (if used during the period the Partnership is required to keep the registration statement current), or arising out of, based upon or resulting from the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements made therein not misleading; provided, however, that the Partnership shall not be liable to any Indemnified Person to the extent that any such claim arises out of, is based upon or results from an untrue statement or alleged untrue statement or omission or alleged omission made in such registration statement, such preliminary, summary or final prospectus or such amendment or supplement, in reliance upon and in conformity with written information furnished to the Partnership by or on behalf of such Indemnified Person specifically for use in the preparation thereof.

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(d) The provisions of Section 7.12(a) and 7.12(b) shall continue to be applicable with respect to the General Partner (and any of the General Partner's Affiliates) after it ceases to be a Partner of the Partnership, during a period of two years subsequent to the effective date of such cessation and for so long thereafter as is required for the Holder to sell all of the Partnership Securities with respect to which, during such two-year period, it has requested inclusion in a registration statement pursuant to Section 7.12(b) or requested that a registration statement be filed pursuant to Section 7.12(a); provided, however, that the Partnership shall not be required to file successive registration statements covering the same Partnership Securities for which registration was demanded during such two-year period. The provisions of Section 7.12(c) shall continue in effect thereafter.

(e) Any request to register Partnership Securities pursuant to this
Section 7.12 shall (i) specify the Partnership Securities intended to be offered and sold by the Person making the request, (ii) express such Person's present intent to offer such Partnership Securities for distribution, (iii) describe the nature or method of the proposed offer and sale of Partnership Securities, and
(iv) contain the undertaking of such Person to provide all such information and materials and take all action as may be required in order to permit the Partnership to comply with all applicable requirements in connection with the registration of such Partnership Securities.

SECTION 7.13 Reliance by Third Parties. Notwithstanding anything to the contrary in this Agreement, any Person dealing with the Partnership shall be entitled to assume that the General Partner and any officer of the General Partner authorized by the General Partner to act on behalf of and in the name of the Partnership has full power and authority to encumber, sell or otherwise use in any manner any and all assets of the Partnership and to enter into any authorized contracts on behalf of the Partnership, and such Person shall be entitled to deal with the General Partner or any such officer as if it were the Partnership's sole party in interest, both legally and beneficially. Each Limited Partner hereby waives any and all defenses or other remedies that may be available against such Person to contest, negate or disaffirm any action of the General Partner or any such officer in connection with any such dealing. In no event shall any Person dealing with the General Partner or any such officer or its representatives be obligated to ascertain that the terms of the Agreement have been complied with or to inquire into the necessity or expedience of any act or action of the General Partner or any such officer or its representatives. Each and every certificate, document or other instrument executed on behalf of the Partnership by the General Partner or its representatives shall be conclusive evidence in favor of any and every Person relying thereon or claiming thereunder that (a) at the time of the execution and delivery of such certificate, document or instrument, this Agreement was in full force and effect, (b) the Person executing and delivering such certificate, document or instrument was duly authorized and empowered to do so for and on behalf of the Partnership and (c) such certificate, document or instrument was duly executed and delivered in accordance with the terms and provisions of this Agreement and is binding upon the Partnership.

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ARTICLE VIII

BOOKS, RECORDS, ACCOUNTING AND REPORTS

SECTION 8.1 Records and Accounting. The General Partner shall keep or cause to be kept at the principal office of the Partnership appropriate books and records with respect to the Partnership's business, including all books and records necessary to provide to the Limited Partners any information required to be provided pursuant to Section 3.4(a). Any books and records maintained by or on behalf of the Partnership in the regular course of its business, including the record of the Record Holders and Assignees of Units or other Partnership Securities, books of account and records of Partnership proceedings, may be kept on, or be in the form of, computer disks, hard drives, punch cards, magnetic tape, photographs, micrographics or any other information storage device; provided, that the books and records so maintained are convertible into clearly legible written form within a reasonable period of time. The books of the Partnership shall be maintained, for financial reporting purposes, on an accrual basis in accordance with U.S. GAAP.

SECTION 8.2 Fiscal Year. The fiscal year of the Partnership shall be a fiscal year ending December 31.

SECTION 8.3 Reports.

(a) As soon as practicable, but in no event later than 120 days after the close of each fiscal year of the Partnership, the General Partner shall cause to be mailed or made available to each Record Holder of a Unit as of a date selected by the General Partner in its discretion, an annual report containing financial statements of the Partnership for such fiscal year of the Partnership, presented in accordance with U.S. GAAP, including a balance sheet and statements of operations, Partnership equity and cash flows, such statements to be audited by a firm of independent public accountants selected by the General Partner.

(b) As soon as practicable, but in no event later than 90 days after the close of each Quarter except the last Quarter of each fiscal year, the General Partner shall cause to be mailed or made available to each Record Holder of a Unit, as of a date selected by the General Partner in its discretion, a report containing unaudited financial statements of the Partnership and such other information as may be required by applicable law, regulation or rule of any National Securities Exchange on which the Units are listed for trading, or as the General Partner determines to be necessary or appropriate.

ARTICLE IX

TAX MATTERS

SECTION 9.1 Tax Returns and Information. The Partnership shall timely file all returns of the Partnership that are required for federal, state and local income tax purposes on the basis of the accrual method and a taxable year ending on December 31. The tax information reasonably required by Record Holders for federal and state income tax reporting purposes with

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respect to a taxable year shall be furnished to them within 90 days of the close of the calendar year in which the Partnership's taxable year ends. The classification, realization and recognition of income, gain, losses and deductions and other items shall be on the accrual method of accounting for federal income tax purposes.

SECTION 9.2 Tax Elections.

(a) The Partnership shall make the election under Section 754 of the Code in accordance with applicable regulations thereunder, subject to the reservation of the right to seek to revoke any such election upon the General Partner's determination that such revocation is in the best interests of the Limited Partners. Notwithstanding any other provision herein contained, for the purposes of computing the adjustments under Section 743(b) of the Code, the General Partner shall be authorized (but not required) to adopt a convention whereby the price paid by a transferee of a Limited Partner Interest will be deemed to be the lowest quoted closing price of the Limited Partner Interests on any National Securities Exchange on which such Limited Partner Interests are traded during the calendar month in which such transfer is deemed to occur pursuant to Section 6.2(g) without regard to the actual price paid by such transferee.

(b) The Partnership shall elect to deduct expenses incurred in organizing the Partnership ratably over a sixty-month period as provided in
Section 709 of the Code.

(c) Except as otherwise provided herein, the General Partner shall determine whether the Partnership should make any other elections permitted by the Code.

SECTION 9.3 Tax Controversies. Subject to the provisions hereof, the General Partner is designated as the Tax Matters Partner (as defined in the Code) and is authorized and required to represent the Partnership (at the Partnership's expense) in connection with all examinations of the Partnership's affairs by tax authorities, including resulting administrative and judicial proceedings, and to expend Partnership funds for professional services and costs associated therewith. Each Partner agrees to cooperate with the General Partner and to do or refrain from doing any or all things reasonably required by the General Partner to conduct such proceedings.

SECTION 9.4 Withholding. Notwithstanding any other provision of this Agreement, the General Partner is authorized to take any action that it determines in its discretion to be necessary or appropriate to cause the Partnership and other Group Members to comply with any withholding requirements established under the Code or any other federal, state or local law including, without limitation, pursuant to Sections 1441, 1442, 1445 and 1446 of the Code. To the extent that the Partnership is required or elects to withhold and pay over to any taxing authority any amount resulting from the allocation or distribution of income to any Partner or Assignee (including, without limitation, by reason of Section 1446 of the Code), the amount withheld may at the discretion of the General Partner be treated by the Partnership as a distribution of cash pursuant to Section 6.3 in the amount of such withholding from such Partner.

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ARTICLE X

ADMISSION OF PARTNERS

SECTION 10.1 Admission of Initial Limited Partners. Effective upon the Distribution, the General Partner shall admit such parties to the Partnership as Initial Limited Partners in respect of the Initial Common Units distributed to them in the Distribution. Each such Initial Limited Partner, by virtue of receiving Initial Common Units in the Distribution, agrees to be bound by, and acknowledges and agrees to all of the terms of, this Agreement without the need to execute this Agreement.

SECTION 10.2 Admission of Substituted Limited Partner. By transfer of a Limited Partner Interest in accordance with Article IV, the transferor shall be deemed to have given the transferee the right to seek admission as a Substituted Limited Partner subject to the conditions of, and in the manner permitted under, this Agreement. A transferor of a Certificate representing a Limited Partner Interest shall, however, only have the authority to convey to a purchaser or other transferee who does not execute and deliver a Transfer Application (a) the right to negotiate such Certificate to a purchaser or other transferee and (b) the right to transfer the right to request admission as a Substituted Limited Partner to such purchaser or other transferee in respect of the transferred Limited Partner Interests. Each transferee of a Limited Partner Interest (including any nominee holder or an agent acquiring such Limited Partner Interest for the account of another Person) who executes and delivers a Transfer Application shall, by virtue of such execution and delivery, be an Assignee and be deemed to have applied to become a Substituted Limited Partner with respect to the Limited Partner Interests so transferred to such Person. Such Assignee shall become a Substituted Limited Partner (x) at such time as the General Partner consents thereto, which consent may be given or withheld in the General Partner's discretion, and (y) when any such admission is shown on the books and records of the Partnership. If such consent is withheld, such transferee shall be an Assignee. An Assignee shall have an interest in the Partnership equivalent to that of a Limited Partner with respect to allocations and distributions, including liquidating distributions, of the Partnership. With respect to voting rights attributable to Limited Partner Interests that are held by Assignees, the General Partner shall be deemed to be the Limited Partner with respect thereto and shall, in exercising the voting rights in respect of such Limited Partner Interests on any matter, vote such Limited Partner Interests at the written direction of the Assignee who is the Record Holder of such Limited Partner Interests. If no such written direction is received, such Limited Partner Interests will not be voted. An Assignee shall have no other rights of a Limited Partner.

SECTION 10.3 Admission of Successor General Partner. A successor General Partner approved pursuant to Section 11.1 or 11.2 or the transferee of or successor to all of the General Partner Interest pursuant to Section 4.6 who is proposed to be admitted as a successor General Partner shall be admitted to the Partnership as the General Partner, effective immediately prior to the withdrawal or removal of the predecessor or transferring General Partner, pursuant to Section 11.1 or 11.2 or the transfer of the General Partner Interest pursuant to Section 4.6; provided, however, that no such successor shall be admitted to the Partnership until compliance with the terms of Section 4.6 has occurred and such successor has executed and delivered such other documents or instruments as may be required to effect such admission. Any

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such successor shall, subject to the terms hereof, carry on the business of the members of the Partnership Group without dissolution.

SECTION 10.4 Admission of Additional Limited Partners.

(a) A Person (other than the General Partner, an Initial Limited Partner or a Substituted Limited Partner) who makes a Capital Contribution to the Partnership in accordance with this Agreement shall be admitted to the Partnership as an Additional Limited Partner only upon furnishing to the General Partner

(i) evidence of acceptance in form satisfactory to the General Partner of all of the terms and conditions of this Agreement, including the power of attorney granted in Section 2.6, and

(ii) such other documents or instruments as may be required in the discretion of the General Partner to effect such Person's admission as an Additional Limited Partner.

(b) Notwithstanding anything to the contrary in this Section 10.4, no Person shall be admitted as an Additional Limited Partner without the consent of the General Partner, which consent may be given or withheld in the General Partner's discretion. The admission of any Person as an Additional Limited Partner shall become effective on the date upon which the name of such Person is recorded as such in the books and records of the Partnership, following the consent of the General Partner to such admission.

SECTION 10.5 Amendment of Agreement and Certificate of Limited Partnership. To effect the admission to the Partnership of any Partner, the General Partner shall take all steps necessary and appropriate under the Delaware Act to amend the records of the Partnership to reflect such admission and, if necessary, to prepare as soon as practicable an amendment to this Agreement and, if required by law, the General Partner shall prepare and file an amendment to the Certificate of Limited Partnership, and the General Partner may for this purpose, among others, exercise the power of attorney granted pursuant to Section 2.6.

ARTICLE XI

WITHDRAWAL OR REMOVAL OF PARTNERS

SECTION 11.1 Withdrawal of the General Partner.

(a) The General Partner shall be deemed to have withdrawn from the Partnership upon the occurrence of any one of the following events (each such event herein referred to as an "Event of Withdrawal");

(i) The General Partner voluntarily withdraws from the Partnership by giving written notice to the other Partners;

(ii) The General Partner transfers all of its rights as General Partner pursuant

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to Section 4.6;

(iii) The General Partner is removed pursuant to Section 11.2;

(iv) The General Partner (A) makes a general assignment for the benefit of creditors; (B) files a voluntary bankruptcy petition for relief under Chapter 7 of the United States Bankruptcy Code;
(C) files a petition or answer seeking for itself a liquidation, dissolution or similar relief (but not a reorganization) under any law; (D) files an answer or other pleading admitting or failing to contest the material allegations of a petition filed against the General Partner in a proceeding of the type described in clauses (A)-(C) of this Section 11.1(a)(iv); or (E) seeks, consents to or acquiesces in the appointment of a trustee (but not a debtor-in-possession), receiver or liquidator of the General Partner or of all or any substantial part of its properties;

(v) A final and non-appealable order of relief under Chapter 7 of the United States Bankruptcy Code is entered by a court with appropriate jurisdiction pursuant to a voluntary or involuntary petition by or against the General Partner; or

(vi) (A) in the event the General Partner is a corporation, a certificate of dissolution or its equivalent is filed for the General Partner, or 90 days expire after the date of notice to the General Partner of revocation of its charter without a reinstatement of its charter, under the laws of its state of incorporation; (B) in the event the General Partner is a partnership or a limited liability company, the dissolution and commencement of winding up of the General Partner; (C) in the event the General Partner is acting in such capacity by virtue of being a trustee of a trust, the termination of the trust; (D) in the event the General Partner is a natural person, his death or adjudication of incompetency; and (E) otherwise in the event of the termination of the General Partner.

If an Event of Withdrawal specified in Section 11.1(a)(iv), (v) or (vi)(A), (B),
(C) or (E) occurs, the withdrawing General Partner shall give notice to the Limited Partners within 30 days after such occurrence. The Partners hereby agree that only the Events of Withdrawal described in this Section 11.1 shall result in the withdrawal of the General Partner from the Partnership.

(b) Withdrawal of the General Partner from the Partnership upon the occurrence of an Event of Withdrawal shall not constitute a breach of this Agreement under the following circumstances: (i) at any time during the period beginning on the Closing Date and ending at 12:00 midnight, Eastern Standard Time, on October 31, 2008, the General Partner voluntarily withdraws by giving at least 90 days' advance notice of its intention to withdraw to the Limited Partners; provided that prior to the effective date of such withdrawal, the withdrawal is approved by Unitholders holding at least a majority of the Outstanding Common Units (excluding Common Units held by the General Partner and its Affiliates) and the General Partner delivers to

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the Partnership an Opinion of Counsel ("Withdrawal Opinion of Counsel") that such withdrawal (following the selection of the successor General Partner) would not result in the loss of the limited liability of any Limited Partner or any Group Member or cause any Group Member to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not previously treated as such); (ii) at any time after 12:00 midnight, Eastern Standard Time, on October 31, 2008, the General Partner voluntarily withdraws by giving at least 90 days' advance notice to the Unitholders, such withdrawal to take effect on the date specified in such notice; (iii) at any time that the General Partner ceases to be the General Partner pursuant to Section 11.1(a)(ii) or is removed pursuant to Section 11.2; or (iv) notwithstanding clause (i) of this sentence, at any time that the General Partner voluntarily withdraws by giving at least 90 days' advance notice of its intention to withdraw to the Limited Partners, such withdrawal to take effect on the date specified in the notice, if at the time such notice is given one Person and its Affiliates (other than the General Partner and its Affiliates) own beneficially or of record or control at least 50% of the Outstanding Units. The withdrawal of the General Partner from the Partnership upon the occurrence of an Event of Withdrawal shall also constitute the withdrawal of the General Partner as general partner or managing member, to the extent applicable, of the other Group Members. If the General Partner gives a notice of withdrawal pursuant to Section 11.1(a)(i), the holders of a Unit Majority, may, prior to the effective date of such withdrawal, elect a successor General Partner. The Person so elected as successor General Partner shall automatically become the successor general partner or managing member, to the extent applicable, of the other Group Members of which the General Partner is a general partner or a managing member. If, prior to the effective date of the General Partner's withdrawal, a successor is not selected by the Unitholders as provided herein or the Partnership does not receive a Withdrawal Opinion of Counsel, the Partnership shall be dissolved in accordance with Section 12.1. Any successor General Partner elected in accordance with the terms of this Section 11.1 shall be subject to the provisions of Section 10.3.

SECTION 11.2 Removal of the General Partner. The General Partner may be removed if such removal is approved by the Unitholders holding at least 80% of the Outstanding Units (including Units held by the General Partner and its Affiliates). Any such action by such holders for removal of the General Partner must also provide for the election of a successor General Partner by the Unitholders holding a majority of the outstanding Common Units voting as a class (including Units held by the General Partner and its Affiliates). Such removal shall be effective immediately following the admission of a successor General Partner pursuant to Section 10.3. The removal of the General Partner shall also automatically constitute the removal of the General Partner as general partner or managing member, to the extent applicable, of the other Group Members of which the General Partner is a general partner or a managing member. If a Person is elected as a successor General Partner in accordance with the terms of this
Section 11.2, such Person shall, upon admission pursuant to Section 10.3, automatically become a successor general partner or managing member, to the extent applicable, of the other Group Members of which the General Partner is a general partner or a managing member. The right of the holders of Outstanding Units to remove the General Partner shall not exist or be exercised unless the Partnership has received an opinion opining as to the matters covered by a Withdrawal Opinion of Counsel. Any successor General Partner elected in accordance with the terms of this Section 11.2 shall be subject to the provisions of Section 10.3. The percentage of the Outstanding

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Units required to remove the General Partner may be amended by the General Partner as described in Section 13.1 hereof.

SECTION 11.3 Interest of Departing Partner and Successor General Partner.

(a) In the event of (i) withdrawal of the General Partner under circumstances where such withdrawal does not violate this Agreement or (ii) removal of the General Partner by the holders of Outstanding Units under circumstances where Cause does not exist, if the successor General Partner is elected in accordance with the terms of Section 11.1 or 11.2, the Departing Partner shall have the option, exercisable prior to the effective date of the departure of such Departing Partner, to require its successor to purchase its General Partner Interest and its general partner interest (or equivalent interest, if any) in the other Group Members and all of its Incentive Distribution Rights (collectively, the "Combined Interest") in exchange for an amount in cash equal to the fair market value of such Combined Interest, such amount to be determined and payable as of the effective date of its departure. If the General Partner is removed by the Unitholders under circumstances where Cause exists or if the General Partner withdraws under circumstances where such withdrawal violates this Agreement, and if a successor General Partner is elected in accordance with the terms of Section 11.1 or 11.2, such successor shall have the option, exercisable prior to the effective date of the departure of such Departing Partner, to purchase the Combined Interest for such fair market value of such Combined Interest of the Departing Partner. In either event, the Departing Partner shall be entitled to receive all reimbursements due such Departing Partner pursuant to Section 7.4, including any employee-related liabilities (including severance liabilities), incurred in connection with the termination of any employees employed by the Departing Partner for the benefit of the Partnership or the other Group Members. For purposes of this Section 11.3(a), the fair market value of the Departing Partner's Combined Interest shall be determined by agreement between the Departing Partner and its successor or, failing agreement within 30 days after the effective date of such Departing Partner's departure, by an independent investment banking firm or other independent expert selected by the Departing Partner and its successor, which, in turn, may rely on other experts, and the determination of which shall be conclusive as to such matter. If such parties cannot agree upon one independent investment banking firm or other independent expert within 45 days after the effective date of such departure, then the Departing Partner shall designate an independent investment banking firm or other independent expert, the Departing Partner's successor shall designate an independent investment banking firm or other independent expert, and such firms or experts shall mutually select a third independent investment banking firm or independent expert, which third independent investment banking firm or other independent expert shall determine the fair market value of the Combined Interest of the Departing Partner. In making its determination, such third independent investment banking firm or other independent expert may consider the then current trading price of Units on any National Securities Exchange on which Units are then listed, the value of the Partnership's assets, the rights and obligations of the Departing Partner and other factors it may deem relevant.

(b) If the Combined Interest is not purchased in the manner set forth in Section 11.3(a), the Departing Partner (or its transferee) shall become a Limited Partner and its General Partner Interest shall be converted into Common Units pursuant to a valuation made by an investment banking firm or other independent expert selected pursuant to Section 11.3(a),

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without reduction in such Partnership Interest (but subject to proportionate dilution by reason of the admission of its successor) and its Incentive Distribution Rights shall continue in full force and effect. Any successor General Partner shall indemnify the Departing Partner (or its transferee) as to all debts and liabilities of the Partnership arising on or after the date on which the Departing Partner (or its transferee) becomes a Limited Partner. For purposes of this Agreement, conversion of the General Partner Interest of the Departing Partner to Common Units will be characterized as if the Departing Partner (or its transferee) contributed its General Partner Interest to the Partnership in exchange for the newly issued Common Units.

(c) If a successor General Partner is elected in accordance with the terms of Section 11.1 or 11.2 and the option described in Section 11.3(a) is not exercised by the party entitled to do so, the successor General Partner shall, at the effective date of its admission to the Partnership, contribute to the Partnership cash in the amount equal to 2/98ths of the Net Agreed Value of the Partnership's assets on such date. In such event, such successor General Partner shall, subject to the following sentence, be entitled to 2% of all Partnership allocations and distributions to which the Departing Partner was entitled. In addition, the successor General Partner shall cause this Agreement to be amended to reflect that, from and after the date of such successor General Partner's admission, the successor General Partner's interest in all Partnership distributions and allocations shall be 2%.

SECTION 11.4 Withdrawal of Limited Partners. No Limited Partner shall have any right to withdraw from the Partnership; provided, however, that when a transferee of a Limited Partner's Limited Partner Interest becomes a Record Holder of the Limited Partner Interest so transferred, such transferring Limited Partner shall cease to be a Limited Partner with respect to the Limited Partner Interest so transferred.

ARTICLE XII

DISSOLUTION AND LIQUIDATION

SECTION 12.1 Dissolution. The Partnership shall not be dissolved by the admission of Substituted Limited Partners or Additional Limited Partners or by the admission of a successor General Partner in accordance with the terms of this Agreement. Upon the removal or withdrawal of the General Partner, if a successor General Partner is elected pursuant to Section 11.1 or 11.2, the Partnership shall not be dissolved and such successor General Partner shall continue the business of the Partnership. The Partnership shall dissolve, and (subject to Section 12.2) its affairs shall be wound up, upon:

(a) an Event of Withdrawal of the General Partner as provided in Section
11.1(a) (other than Section 11.1(a)(ii)), unless a successor is elected and an Opinion of Counsel is received as provided in Section 11.1(b) or 11.2 and such successor is admitted to the Partnership pursuant to Section 10.3;

(b) an election to dissolve the Partnership by the General Partner that is approved by the holders of a Unit Majority;

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(c) the entry of a decree of judicial dissolution of the Partnership pursuant to the provisions of the Delaware Act; or

(d) the sale of all or substantially all of the assets and properties of the Partnership Group.

SECTION 12.2 Continuation of the Business of the Partnership After Dissolution. Upon (a) dissolution of the Partnership following an Event of Withdrawal caused by the withdrawal or removal of the General Partner as provided in Section 11.1(a)(i) or (iii) and the failure of the Partners to select a successor to such Departing Partner pursuant to Section 11.1 or 11.2, then within 90 days thereafter, or (b) dissolution of the Partnership upon an event constituting an Event of Withdrawal as defined in Section 11.1(a)(iv), (v) or (vi), then, to the maximum extent permitted by law, within 180 days thereafter, the holders of a Unit Majority may elect to reconstitute the Partnership and continue its business on the same terms and conditions set forth in this Agreement by forming a new limited partnership on terms identical to those set forth in this Agreement and having as the successor General Partner a Person approved by the holders of a Unit Majority. Unless such an election is made within the applicable time period as set forth above, the Partnership shall conduct only activities necessary to wind up its affairs. If such an election is so made, then:

(i) the reconstituted Partnership shall continue unless earlier dissolved in accordance with this Article XII;

(ii) if the successor General Partner is not the former General Partner, then the interest of the former General Partner shall be treated in the manner provided in Section 11.3; and

(iii) all necessary steps shall be taken to cancel this Agreement and the Certificate of Limited Partnership and to enter into and, as necessary, to file a new partnership agreement and certificate of limited partnership, and the successor General Partner may for this purpose exercise the powers of attorney granted the General Partner pursuant to Section 2.6; provided, that the right of the holders of a Unit Majority to approve a successor General Partner and to reconstitute and to continue the business of the Partnership shall not exist and may not be exercised unless the Partnership has received an Opinion of Counsel that (x) the exercise of the right would not result in the loss of limited liability of any Limited Partner and (y) neither the Partnership, the reconstituted limited partnership nor the Operating Partnership or any other Group Member would be treated as an association taxable as a corporation or otherwise be taxable as an entity for federal income tax purposes upon the exercise of such right to continue.

SECTION 12.3 Liquidator. Upon dissolution of the Partnership, unless the Partnership is continued under an election to reconstitute and continue the Partnership pursuant to Section 12.2, the General Partner shall select one or more Persons to act as Liquidator, which may be the General Partner. The Liquidator (if other than the General Partner) shall be entitled to receive such compensation for its services as may be approved by holders of at least a majority

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of the Outstanding Common Units. The Liquidator (if other than the General Partner) shall agree not to resign at any time without 15 days' prior notice and may be removed at any time, with or without cause, by notice of removal approved by holders of at least a majority of the Outstanding Common Units. Upon dissolution, removal or resignation of the Liquidator, a successor and substitute Liquidator (who shall have and succeed to all rights, powers and duties of the original Liquidator) shall within 30 days thereafter be approved by holders of at least a majority of the Outstanding Common Units. The right to approve a successor or substitute Liquidator in the manner provided herein shall be deemed to refer also to any such successor or substitute Liquidator approved in the manner herein provided. Except as expressly provided in this Article XII, the Liquidator approved in the manner provided herein shall have and may exercise, without further authorization or consent of any of the parties hereto, all of the powers conferred upon the General Partner under the terms of this Agreement (but subject to all of the applicable limitations, contractual and otherwise, upon the exercise of such powers, other than the limitation on sale set forth in Section 7.3(b)) to the extent necessary or desirable in the good faith judgment of the Liquidator to carry out the duties and functions of the Liquidator hereunder for and during such period of time as shall be reasonably required in the good faith judgment of the Liquidator to complete the winding up and liquidation of the Partnership as provided for herein.

SECTION 12.4 Liquidation. The Liquidator shall proceed to dispose of the assets of the Partnership, discharge its liabilities, and otherwise wind up its affairs in such manner and over such period as the Liquidator determines to be in the best interest of the Partners, subject to Section 17-804 of the Delaware Act and the following:

(a) The assets may be disposed of by public or private sale or by distribution in kind to one or more Partners on such terms as the Liquidator and such Partner or Partners may agree. If any property is distributed in kind, the Partner receiving the property shall be deemed for purposes of Section 12.4(c) to have received cash equal to its fair market value; and contemporaneously therewith, appropriate cash distributions must be made to the other Partners. The Liquidator may, in its absolute discretion, defer liquidation or distribution of the Partnership's assets for a reasonable time if it determines that an immediate sale or distribution of all or some of the Partnership's assets would be impractical or would cause undue loss to the Partners. The Liquidator may, in its absolute discretion, distribute the Partnership's assets, in whole or in part, in kind if it determines that a sale would be impractical or would cause undue loss to the Partners.

(b) Liabilities of the Partnership include amounts owed to the Liquidator as compensation for serving in such capacity (subject to the terms of
Section 12.3) and amounts to Partners otherwise than in respect of their distribution rights under Article VI. With respect to any liability that is contingent, conditional or unmatured or is otherwise not yet due and payable, the Liquidator shall either settle such claim for such amount as it thinks appropriate or establish a reserve of cash or other assets to provide for its payment. When paid, any unused portion of the reserve shall be distributed as additional liquidation proceeds.

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(c) All property and all cash in excess of that required to discharge liabilities as provided in Section 12.4(b) shall be distributed to the Partners in accordance with, and to the extent of, the positive balances in their respective Capital Accounts, as determined after taking into account all Capital Account adjustments (other than those made by reason of distributions pursuant to this Section 12.4(c)) for the taxable year of the Partnership during which the liquidation of the Partnership occurs (with such date of occurrence being determined pursuant to Treasury Regulation Section 1.704-1(b)(2)(ii)(g)), and such distribution shall be made by the end of such taxable year (or, if later, within 90 days after said date of such occurrence).

SECTION 12.5 Cancellation of Certificate of Limited Partnership. Upon the completion of the distribution of Partnership cash and property as provided in Section 12.4 in connection with the liquidation of the Partnership, the Partnership shall be terminated and the Certificate of Limited Partnership and all qualifications of the Partnership as a foreign limited partnership in jurisdictions other than the State of Delaware shall be canceled and such other actions as may be necessary to terminate the Partnership shall be taken.

SECTION 12.6 Return of Contributions. The General Partner shall not be personally liable for, and shall have no obligation to contribute or loan any monies or property to the Partnership to enable it to effectuate, the return of the Capital Contributions of the Limited Partners or Unitholders, or any portion thereof, it being expressly understood that any such return shall be made solely from Partnership assets.

SECTION 12.7 Waiver of Partition. To the maximum extent permitted by law, each Partner hereby waives any right to partition of the Partnership property.

SECTION 12.8 Capital Account Restoration. No Limited Partner shall have any obligation to restore any negative balance in its Capital Account upon liquidation of the Partnership. The General Partner shall be obligated to restore any negative balance in its Capital Account upon liquidation of its interest in the Partnership by the end of the taxable year of the Partnership during which such liquidation occurs, or, if later, within 90 days after the date of such liquidation.

ARTICLE XIII

AMENDMENT OF PARTNERSHIP AGREEMENT; MEETINGS; RECORD DATE

SECTION 13.1 Amendment to be Adopted Solely by the General Partner. Each Partner agrees that the General Partner, without the approval of any Partner or Assignee, may amend any provision of this Agreement and execute, swear to, acknowledge, deliver, file and record whatever documents may be required in connection therewith, to reflect:

(a) a change in the name of the Partnership, the location of the principal place of business of the Partnership, the registered agent of the Partnership or the registered office of the Partnership;

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(b) admission, substitution, withdrawal or removal of Partners in accordance with this Agreement;

(c) a change that, in the sole discretion of the General Partner, is necessary or advisable to qualify or continue the qualification of the Partnership as a limited partnership or a partnership in which the Limited Partners have limited liability under the laws of any state or to ensure that the Group Members will not be treated as associations taxable as corporations or otherwise taxed as entities for federal income tax purposes;

(d) a change that, in the discretion of the General Partner, (i) does not adversely affect the Limited Partners (including any particular class of Partnership Interests as compared to other classes of Partnership Interests) in any material respect, (ii) is necessary or advisable to (A) satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or judicial authority or contained in any federal or state statute (including the Delaware Act) or (B) facilitate the trading of the Units (including the division of any class or classes of Outstanding Units into different classes to facilitate uniformity of tax consequences within such classes of Units) or comply with any rule, regulation, guideline or requirement of any National Securities Exchange on which the Units are or will be listed for trading, compliance with any of which the General Partner determines in its discretion to be in the best interests of the Partnership and the Limited Partners, (iii) is necessary or advisable in connection with action taken by the General Partner pursuant to Section 5.10, (iv) is required to effect the intent expressed in the Registration Statement or the intent of the provisions of this Agreement or is otherwise contemplated by this Agreement or (v) is required to conform to proposed or promulgated Treasury Regulations under Subchapter K of the Code regarding compensatory and noncompensatory options to acquire a Partnership Security;

(e) a change in the fiscal year or taxable year of the Partnership and any changes that, in the discretion of the General Partner, are necessary or advisable as a result of a change in the fiscal year or taxable year of the Partnership including, if the General Partner shall so determine, a change in the definition of "Quarter" and the dates on which distributions are to be made by the Partnership;

(f) an amendment that is necessary, in the Opinion of Counsel, to prevent the Partnership, or the General Partner or its directors, officers, trustees or agents from in any manner being subjected to the provisions of the Investment Company Act of 1940, as amended, the Investment Advisers Act of 1940, as amended, or "plan asset" regulations adopted under the Employee Retirement Income Security Act of 1974, as amended, regardless of whether such are substantially similar to plan asset regulations currently applied or proposed by the United States Department of Labor;

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(g) subject to the terms of Section 5.7, an amendment that, in the discretion of the General Partner, is necessary or advisable in connection with the authorization of issuance of any class or series of Partnership Securities pursuant to Section 5.6;

(h) any amendment expressly permitted in this Agreement to be made by the General Partner acting alone;'

(i) an amendment effected, necessitated or contemplated by a Merger Agreement approved in accordance with Section 14.3;

(j) an amendment that, in the discretion of the General Partner, is necessary or advisable to reflect, account for and deal with appropriately the formation by the Partnership of, or investment by the Partnership in, any corporation, partnership, joint venture, limited liability company or other entity, in connection with the conduct by the Partnership of activities permitted by the terms of
Section 2.4;

(k) a merger or conveyance pursuant to Section 14.3(d);

(l) an amendment to Section 11.2 that would reduce the percentage of the Outstanding Units required for the Unitholders to remove the General Partner; provided, however, that once such required percentage has been reduced, it may be further reduced by the General Partner but such required percentage may not be increased without a vote of the Unitholders; provided further, however, that no such amendment may provide that any class Units may vote separately as a class to remove the General Partner;

(m) an amendment to the definition of "Outstanding" contained in Section 1.1 hereof to increase from 20% or more the percentage of Outstanding Partnership Securities, that if at any time acquired by any Person or Group, shall not be voted on any matter and shall not be considered to be Outstanding for the other purposes described in such definition; provided, however, that once such percentage has been increased, it may be further increased by the General Partner, but such required percentage may not be reduced without a vote of the Unitholders; or

(n) any other amendments substantially similar to the foregoing.

SECTION 13.2 Amendment Procedures. Except as provided in Sections 13.1 and 13.3, all amendments to this Agreement shall be made in accordance with the following requirements. Amendments to this Agreement may be proposed only by or with the consent of the General Partner which consent may be given or withheld in its sole discretion. A proposed amendment shall be effective upon its approval by the holders of a Unit Majority, unless a greater or different percentage is required under this Agreement or by Delaware law. Each proposed amendment that requires the approval of the holders of a specified percentage of Outstanding Units shall be set forth in a writing that contains the text of the proposed amendment. If such an amendment is proposed, the General Partner shall seek the written approval of the requisite percentage of Outstanding Units or call a meeting of the Unitholders to

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consider and vote on such proposed amendment. The General Partner shall notify all Record Holders upon final adoption of any such proposed amendments.

SECTION 13.3 Amendment Requirements.

(a) Notwithstanding the provisions of Sections 13.1 and 13.2, no provision of this Agreement that establishes a percentage of Outstanding Units (including Units deemed owned by the General Partner) required to take any action shall be amended, altered, changed, repealed or rescinded in any respect that would have the effect of reducing such voting percentage unless such amendment is approved by the written consent or the affirmative vote of holders of Outstanding Units whose aggregate Outstanding Units constitute not less than the voting requirement sought to be reduced.

(b) Notwithstanding the provisions of Sections 13.1 and 13.2, no amendment to this Agreement may (i) enlarge the obligations of any Limited Partner without its consent, unless such shall be deemed to have occurred as a result of an amendment approved pursuant to Section 13.3(c), (ii) enlarge the obligations of, restrict in any way any action by or rights of, or reduce in any way the amounts distributable, reimbursable or otherwise payable to, the General Partner or any of its Affiliates without its consent, which consent may be given or withheld in its sole discretion, (iii) change Section 12.1(b), or (iv) change the term of the Partnership or, except as set forth in Section 12.1(b), give any Person the right to dissolve the Partnership.

(c) Except as provided in Section 14.3, and without limitation of the General Partner's authority to adopt amendments to this Agreement without the approval of any Partners or Assignees as contemplated in Section 13.1, any amendment that would have a material adverse effect on the rights or preferences of any class of Partnership Interests in relation to other classes of Partnership Interests must be approved by the holders of not less than a majority of the Outstanding Partnership Interests of the class affected.

(d) Notwithstanding any other provision of this Agreement, except for amendments pursuant to Section 13.1 and except as otherwise provided by Section 14.3(b), no amendments shall become effective without the approval of the holders of at least 90% of the Outstanding Units voting as a single class unless the Partnership obtains an Opinion of Counsel to the effect that such amendment will not affect the limited liability of any Limited Partner under applicable law.

(e) Except as provided in Section 13.1, this Section 13.3 shall only be amended with the approval of the holders of at least 90% of the Outstanding Units.

SECTION 13.4 Special Meetings. All acts of Limited Partners to be taken pursuant to this Agreement shall be taken in the manner provided in this Article XIII. Special meetings of the Limited Partners may be called by the General Partner or by Limited Partners owning 20% or more of the Outstanding Units of the class or classes for which a meeting is proposed. Limited Partners shall call a special meeting by delivering to the General Partner one or more requests in writing stating that the signing Limited Partners wish to call a special meeting and indicating the general or specific purposes for which the special meeting is to be

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called. Within 60 days after receipt of such a call from Limited Partners or within such greater time as may be reasonably necessary for the Partnership to comply with any statutes, rules, regulations, listing agreements or similar requirements governing the holding of a meeting or the solicitation of proxies for use at such a meeting, the General Partner shall send a notice of the meeting to the Limited Partners either directly or indirectly through the Transfer Agent. A meeting shall be held at a time and place determined by the General Partner on a date not less than 10 days nor more than 60 days after the mailing of notice of the meeting. Limited Partners shall not vote on matters that would cause the Limited Partners to be deemed to be taking part in the management and control of the business and affairs of the Partnership so as to jeopardize the Limited Partners' limited liability under the Delaware Act or the law of any other state in which the Partnership is qualified to do business.

SECTION 13.5 Notice of a Meeting. Notice of a meeting called pursuant to Section 13.4 shall be given to the Record Holders of the class or classes of Units for which a meeting is proposed in writing by mail or other means of written communication in accordance with Section 16.1. The notice shall be deemed to have been given at the time when deposited in the mail or sent by other means of written communication.

SECTION 13.6 Record Date. For purposes of determining the Limited Partners entitled to notice of or to vote at a meeting of the Limited Partners or to give approvals without a meeting as provided in Section 13.11 the General Partner may set a Record Date, which shall not be less than 10 nor more than 60 days before (a) the date of the meeting (unless such requirement conflicts with any rule, regulation, guideline or requirement of any National Securities Exchange on which the Units are listed for trading, in which case the rule, regulation, guideline or requirement of such exchange shall govern) or (b) in the event that approvals are sought without a meeting, the date by which Limited Partners are requested in writing by the General Partner to give such approvals.

SECTION 13.7 Adjournment. When a meeting is adjourned to another time or place, notice need not be given of the adjourned meeting and a new Record Date need not be fixed, if the time and place thereof are announced at the meeting at which the adjournment is taken, unless such adjournment shall be for more than 45 days. At the adjourned meeting, the Partnership may transact any business which might have been transacted at the original meeting. If the adjournment is for more than 45 days or if a new Record Date is fixed for the adjourned meeting, a notice of the adjourned meeting shall be given in accordance with this Article XIII.

SECTION 13.8 Waiver of Notice; Approval of Meeting; Approval of Minutes. The transactions of any meeting of Limited Partners, however called and noticed, and whenever held, shall be as valid as if it had occurred at a meeting duly held after regular call and notice, if a quorum is present either in person or by proxy, and if, either before or after the meeting, Limited Partners representing such quorum who were present in person or by proxy and entitled to vote, sign a written waiver of notice or an approval of the holding of the meeting or an approval of the minutes thereof. All waivers and approvals shall be filed with the Partnership records or made a part of the minutes of the meeting. Attendance of a Limited Partner at a meeting shall constitute a waiver of notice of the meeting, except when the Limited Partner does not approve, at the beginning of the meeting, of the transaction of any business because the

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meeting is not lawfully called or convened; and except that attendance at a meeting is not a waiver of any right to disapprove the consideration of matters required to be included in the notice of the meeting, but not so included, if the disapproval is expressly made at the meeting.

SECTION 13.9 Quorum. The holders of a majority of the Outstanding Units of the class or classes for which a meeting has been called (including Outstanding Units deemed owned by the General Partner) represented in person or by proxy shall constitute a quorum at a meeting of Limited Partners of such class or classes unless any such action by the Limited Partners requires approval by holders of a greater percentage of such Units, in which case the quorum shall be such greater percentage. At any meeting of the Limited Partners duly called and held in accordance with this Agreement at which a quorum is present, the act of Limited Partners holding Outstanding Units that in the aggregate represent a majority of the Outstanding Units entitled to vote and be present in person or by proxy at such meeting shall be deemed to constitute the act of all Limited Partners, unless a greater or different percentage is required with respect to such action under the provisions of this Agreement, in which case the act of the Limited Partners holding Outstanding Units that in the aggregate represent at least such greater or different percentage shall be required. The Limited Partners present at a duly called or held meeting at which a quorum is present may continue to transact business until adjournment, notwithstanding the withdrawal of enough Limited Partners to leave less than a quorum, if any action taken (other than adjournment) is approved by the required percentage of Outstanding Units specified in this Agreement (including Outstanding Units deemed owned by the General Partner). In the absence of a quorum any meeting of Limited Partners may be adjourned from time to time by the affirmative vote of holders of at least a majority of the Outstanding Units entitled to vote at such meeting (including Outstanding Units deemed owned by the General Partner) represented either in person or by proxy, but no other business may be transacted, except as provided in Section 13.7.

SECTION 13.10 Conduct of a Meeting. The General Partner shall have full power and authority concerning the manner of conducting any meeting of the Limited Partners or solicitation of approvals in writing, including the determination of Persons entitled to vote, the existence of a quorum, the satisfaction of the requirements of Section 13.4, the conduct of voting, the validity and effect of any proxies and the determination of any controversies, votes or challenges arising in connection with or during the meeting or voting. The General Partner shall designate a Person to serve as chairman of any meeting and shall further designate a Person to take the minutes of any meeting. All minutes shall be kept with the records of the Partnership maintained by the General Partner. The General Partner may make such other regulations consistent with applicable law and this Agreement as it may deem advisable concerning the conduct of any meeting of the Limited Partners or solicitation of approvals in writing, including regulations in regard to the appointment of proxies, the appointment and duties of inspectors of votes and approvals, the submission and examination of proxies and other evidence of the right to vote, and the revocation of approvals in writing.

SECTION 13.11 Action Without a Meeting. If authorized by the General Partner, any action that may be taken at a meeting of the Limited Partners may be taken without a meeting if an approval in writing setting forth the action so taken is signed by Limited Partners owning not less than the minimum percentage of the Outstanding Units (including Units deemed

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owned by the General Partner) that would be necessary to authorize or take such action at a meeting at which all the Limited Partners were present and voted (unless such provision conflicts with any rule, regulation, guideline or requirement of any National Securities Exchange on which the Units are listed for trading, in which case the rule, regulation, guideline or requirement of such exchange shall govern). Prompt notice of the taking of action without a meeting shall be given to the Limited Partners who have not approved in writing. The General Partner may specify that any written ballot submitted to Limited Partners for the purpose of taking any action without a meeting shall be returned to the Partnership within the time period, which shall be not less than 20 days, specified by the General Partner. If a ballot returned to the Partnership does not vote all of the Units held by the Limited Partners, the Partnership shall be deemed to have failed to receive a ballot for the Units that were not voted. If approval of the taking of any action by the Limited Partners is solicited by any Person other than by or on behalf of the General Partner, the written approvals shall have no force and effect unless and until
(a) they are deposited with the Partnership in care of the General Partner, (b) approvals sufficient to take the action proposed are dated as of a date not more than 90 days prior to the date sufficient approvals are deposited with the Partnership and (c) an Opinion of Counsel is delivered to the General Partner to the effect that the exercise of such right and the action proposed to be taken with respect to any particular matter (i) will not cause the Limited Partners to be deemed to be taking part in the management and control of the business and affairs of the Partnership so as to jeopardize the Limited Partners' limited liability, and (ii) is otherwise permissible under the state statutes then governing the rights, duties and liabilities of the Partnership and the Partners.

SECTION 13.12 Voting and Other Rights.

(a) Only those Record Holders of the Units on the Record Date set pursuant to Section 13.6 (and also subject to the limitations contained in the definition of "Outstanding") shall be entitled to notice of, and to vote at, a meeting of Limited Partners or to act with respect to matters as to which the holders of the Outstanding Units have the right to vote or to act. All references in this Agreement to votes of, or other acts that may be taken by, the Outstanding Units shall be deemed to be references to the votes or acts of the Record Holders of such Outstanding Units.

(b) With respect to Units that are held for a Person's account by another Person (such as a broker, dealer, bank, trust company or clearing corporation, or an agent of any of the foregoing), in whose name such Units are registered, such other Person shall, in exercising the voting rights in respect of such Units on any matter, and unless the arrangement between such Persons provides otherwise, vote such Units in favor of, and at the direction of, the Person who is the beneficial owner, and the Partnership shall be entitled to assume it is so acting without further inquiry. The provisions of this Section
13.12(b) (as well as all other provisions of this Agreement) are subject to the provisions of Section 4.3.

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ARTICLE XIV

MERGER

SECTION 14.1 Authority. The Partnership may merge or consolidate with one or more corporations, limited liability companies, business trusts or associations, real estate investment trusts, common law trusts or unincorporated businesses, including a general partnership or limited partnership, formed under the laws of any state of the United States of America, pursuant to a written agreement of merger or consolidation ("Merger Agreement") in accordance with this Article XIV.

SECTION 14.2 Procedure for Merger or Consolidation. Merger or consolidation of the Partnership pursuant to this Article XIV requires the prior approval of the General Partner. If the General Partner shall determine, in the exercise of its discretion, to consent to the merger or consolidation, the General Partner shall approve the Merger Agreement, which shall set forth:

(a) the names and jurisdictions of formation or organization of each of the business entities proposing to merge or consolidate;

(b) the name and jurisdiction of formation or organization of the business entity that is to survive the proposed merger or consolidation (the "Surviving Business Entity");

(c) the terms and conditions of the proposed merger or consolidation;

(d) the manner and basis of exchanging or converting the equity securities of each constituent business entity for, or into, cash, property or general or limited partner interests, rights, securities or obligations of the Surviving Business Entity; and (i) if any general or limited partner interests, securities or rights of any constituent business entity are not to be exchanged or converted solely for, or into, cash, property or general or limited partner interests, rights, securities or obligations of the Surviving Business Entity, the cash, property or general or limited partner interests, rights, securities or obligations of any limited partnership, corporation, trust or other entity (other than the Surviving Business Entity) which the holders of such general or limited partner interests, securities or rights are to receive in exchange for, or upon conversion of their general or limited partner interests, securities or rights, and (ii) in the case of securities represented by certificates, upon the surrender of such certificates, which cash, property or general or limited partner interests, rights, securities or obligations of the Surviving Business Entity or any general or limited partnership, corporation, trust or other entity (other than the Surviving Business Entity), or evidences thereof, are to be delivered;

(e) a statement of any changes in the constituent documents or the adoption of new constituent documents (the articles or certificate of incorporation, articles of trust, declaration of trust, certificate or agreement of limited partnership or other similar charter or governing document) of the Surviving Business Entity to be effected by

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such merger or consolidation;

(f) the effective time of the merger, which may be the date of the filing of the certificate of merger pursuant to Section 14.4 or a later date specified in or determinable in accordance with the Merger Agreement (provided, that if the effective time of the merger is to be later than the date of the filing of the certificate of merger, the effective time shall be fixed no later than the time of the filing of the certificate of merger and stated therein); and

(g) such other provisions with respect to the proposed merger or consolidation as are deemed necessary or appropriate by the General Partner.

SECTION 14.3 Approval by Limited Partners of Merger or Consolidation.

(a) Except as provided in Section 14.3(d), the General Partner, upon its approval of the Merger Agreement, shall direct that the Merger Agreement be submitted to a vote of Limited Partners, whether at a special meeting or by written consent, in either case in accordance with the requirements of Article
XIII. A copy or a summary of the Merger Agreement shall be included in or enclosed with the notice of a special meeting or the written consent.

(b) Except as provided in Section 14.3(d), the Merger Agreement shall be approved upon receiving the affirmative vote or consent of the holders of a Unit Majority unless the Merger Agreement contains any provision that, if contained in an amendment to this Agreement, the provisions of this Agreement or the Delaware Act would require for its approval the vote or consent of a greater percentage of the Outstanding Units or of any class of Limited Partners, in which case such greater percentage vote or consent shall be required for approval of the Merger Agreement.

(c) Except as provided in Section 14.3(d), after such approval by vote or consent of the Limited Partners, and at any time prior to the filing of the certificate of merger pursuant to Section 14.4, the merger or consolidation may be abandoned pursuant to provisions therefor, if any, set forth in the Merger Agreement.

(d) Notwithstanding anything else contained in this Article XIV or in this Agreement, the General Partner is permitted, in its discretion, without Limited Partner approval, to merge the Partnership or any Group Member into, or convey all of the Partnership's assets to, another limited liability entity which shall be newly formed and shall have no assets, liabilities or operations at the time of such Merger other than those it receives from the Partnership or other Group Member if (i) the General Partner has received an Opinion of Counsel that the merger or conveyance, as the case may be, would not result in the loss of the limited liability of any Limited Partner or any Group Member or cause the Partnership or any Group Member to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not previously treated as such), (ii) the sole purpose of such merger or conveyance is to effect a mere change in the legal form of the Partnership into another limited liability entity and (iii) the governing instruments of the new entity provide the Limited Partners and the General Partner with the same rights and obligations as are herein contained.

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SECTION 14.4 Certificate of Merger. Upon the required approval by the General Partner and the Unitholders of a Merger Agreement, a certificate of merger shall be executed and filed with the Secretary of State of the State of Delaware in conformity with the requirements of the Delaware Act.

SECTION 14.5 Effect of Merger.

(a) At the effective time of the certificate of merger:

(i) all of the rights, privileges and powers of each of the business entities that has merged or consolidated, and all property, real, personal and mixed, and all debts due to any of those business entities and all other things and causes of action belonging to each of those business entities, shall be vested in the Surviving Business Entity and after the merger or consolidation shall be the property of the Surviving Business Entity to the extent they were of each constituent business entity;

(ii) the title to any real property vested by deed or otherwise in any of those constituent business entities shall not revert and is not in any way impaired because of the merger or consolidation;

(iii) all rights of creditors and all liens on or security interests in property of any of those constituent business entities shall be preserved unimpaired; and

(iv) all debts, liabilities and duties of those constituent business entities shall attach to the Surviving Business Entity and may be enforced against it to the same extent as if the debts, liabilities and duties had been incurred or contracted by it.

(b) A merger or consolidation effected pursuant to this Article shall not be deemed to result in a transfer or assignment of assets or liabilities from one entity to another.

ARTICLE XV

GENERAL PROVISIONS

SECTION 15.1 Addresses and Notices. Any notice, demand, request, report or proxy materials required or permitted to be given or made to a Partner or Assignee under this Agreement shall be in writing and shall be deemed given or made when delivered in person or when sent by first class United States mail or by other means of written communication to the Partner or Assignee at the address described below. Any notice, payment or report to be given or made to a Partner or Assignee hereunder shall be deemed conclusively to have been given or made, and the obligation to give such notice or report or to make such payment shall be deemed conclusively to have been fully satisfied, upon sending of such notice, payment or report to the Record Holder of such Partnership Securities at his address as shown on the records of the Transfer Agent or as otherwise shown on the records of the Partnership, regardless of any claim

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of any Person who may have an interest in such Partnership Securities by reason of any assignment or otherwise. An affidavit or certificate of making of any notice, payment or report in accordance with the provisions of this Section 16.1 executed by the General Partner, the Transfer Agent or the mailing organization shall be prima facie evidence of the giving or making of such notice, payment or report. If any notice, payment or report addressed to a Record Holder at the address of such Record Holder appearing on the books and records of the Transfer Agent or the Partnership is returned by the United States Postal Service marked to indicate that the United States Postal Service is unable to deliver it, such notice, payment or report and any subsequent notices, payments and reports shall be deemed to have been duly given or made without further mailing (until such time as such Record Holder or another Person notifies the Transfer Agent or the Partnership of a change in his address) if they are available for the Partner or Assignee at the principal office of the Partnership for a period of one year from the date of the giving or making of such notice, payment or report to the other Partners and Assignees. Any notice to the Partnership shall be deemed given if received by the General Partner at the principal office of the Partnership designated pursuant to Section 2.3. The General Partner may rely and shall be protected in relying on any notice or other document from a Partner, Assignee or other Person if believed by it to be genuine.

SECTION 15.2 Further Action. The parties shall execute and deliver all documents, provide all information and take or refrain from taking action as may be necessary or appropriate to achieve the purposes of this Agreement.

SECTION 15.3 Binding Effect. This Agreement shall be binding upon and inure to the benefit of the parties hereto and their heirs, executors, administrators, successors, legal representatives and permitted assigns.

SECTION 15.4 Integration. This Agreement constitutes the entire agreement among the parties hereto pertaining to the subject matter hereof and supersedes all prior agreements and understandings pertaining thereto.

SECTION 15.5 Creditors. None of the provisions of this Agreement shall be for the benefit of, or shall be enforceable by, any creditor of the Partnership.

SECTION 15.6 Waiver. No failure by any party to insist upon the strict performance of any covenant, duty, agreement or condition of this Agreement or to exercise any right or remedy consequent upon a breach thereof shall constitute waiver of any such breach of any other covenant, duty, agreement or condition.

SECTION 15.7 Counterparts. This Agreement may be executed in counterparts, all of which together shall constitute an agreement binding on all the parties hereto, notwithstanding that all such parties are not signatories to the original or the same counterpart. Each party shall become bound by this Agreement immediately upon affixing its signature hereto or, in the case of a Person acquiring a Unit, upon accepting the certificate evidencing such Unit or executing and delivering a Transfer Application as herein described, independently of the signature of any other party.

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SECTION 15.8 Applicable Law. This Agreement shall be construed in accordance with and governed by the laws of the State of Delaware, without regard to the principles of conflicts of law.

SECTION 15.9 Invalidity of Provisions. If any provision of this Agreement is or becomes invalid, illegal or unenforceable in any respect, the validity, legality and enforceability of the remaining provisions contained herein shall not be affected thereby.

SECTION 15.10 Consent of Partners. Each Partner hereby expressly consents and agrees that, whenever in this Agreement it is specified that an action may be taken upon the affirmative vote or consent of less than all of the Partners, such action may be so taken upon the concurrence of less than all of the Partners and each Partner shall be bound by the results of such action.

[Signatures on following page]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first written above.

GENERAL PARTNER:

RIO VISTA GP LLC

By:/s/ Richard Shore, Jr.
   --------------------------------
       Richard Shore, Jr.,
       President

ORGANIZATIONAL LIMITED PARTNER:

PENN OCTANE CORPORATION

By:/s/ Richard Shore, Jr.
   --------------------------------
       Richard Shore, Jr.,
       President

LIMITED PARTNERS:

All Limited Partners now and hereafter
admitted as Limited Partners of the
Partnership, pursuant to powers of
attorney now and hereafter executed in
favor of, and granted and delivered to
the General Partner.

RIO VISTA GP LLC

By:/s/ Richard Shore, Jr.
   --------------------------------
       Richard Shore, Jr.,
       President

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EXHIBIT A
TO THE FIRST AMENDED AND RESTATED
AGREEMENT OF LIMITED PARTNERSHIP OF
RIO VISTA ENERGY PARTNERS L.P.
CERTIFICATE EVIDENCING COMMON UNITS
REPRESENTING LIMITED PARTNER INTERESTS IN
RIO VISTA ENERGY PARTNERS L.P.

No. Common Units In accordance with Section 4.1 of the First Amended and Restated Agreement of Limited Partnership of Rio Vista Energy Partners L.P., as amended, supplemented or restated from time to time (the "Partnership Agreement"), Rio Vista Energy Partners L.P., a Delaware limited partnership (the "Partnership"), hereby certifies that _______________ (the "Holder") is the registered owner of Common Units representing limited partner interests in the Partnership (the "Common Units") transferable on the books of the Partnership, in person or by duly authorized attorney, upon surrender of this Certificate properly endorsed and accompanied by a properly executed application for transfer of the Common Units represented by this Certificate. The rights, preferences and limitations of the Common Units are set forth in, and this Certificate and the Common Units represented hereby are issued and shall in all respects be subject to the terms and provisions of, the Partnership Agreement. Copies of the Partnership Agreement are on file at, and will be furnished without charge on delivery of written request to the Partnership at, the principal office of the Partnership located at 820 Gessner Road, Suite 1285, Houston, Texas 77024. Capitalized terms used herein but not defined shall have the meanings given them in the Partnership Agreement.

The Holder, by accepting this Certificate, is deemed to have (i) requested admission as, and agreed to become, a Limited Partner and to have agreed to comply with and be bound by and to have executed the Partnership Agreement, (ii) represented and warranted that the Holder has all right, power and authority and, if an individual, the capacity necessary to enter into the Partnership Agreement, (iii) granted the powers of attorney provided for in the Partnership Agreement and (iv) made the waivers and given the consents and approvals contained in the Partnership Agreement.

This Certificate shall not be valid far any purpose unless it has been countersigned and registered by the Transfer Agent and Registrar.

Dated:____________________               RIO  VISTA  ENERGY  PARTNERS  L.P.

Countersigned and Registered by:         By:  Rio Vista GP LLC,
                                         its General Partner

___________________________________      By:____________________________________
as  Transfer  Agent  and  Registrar      Name:__________________________________

By:________________________________      By:____________________________________
     Authorized Signature                     Secretary

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[REVERSE OF CERTIFICATE]

ABBREVIATIONS

The following abbreviations, when used in the inscription on the face of this Certificate, shall be construed as follows according to applicable laws or regulations:

TEN COM --  as tenants in common                      UNIF GIFT/TRANSFERS MIN ACT
TEN ENT --  as tenants by the entireties Custodian
                                                      (Cust)         (Minor)
JT TEN --   as joint tenants with right of            under Uniform Gifts/Transfers to CD
            survivorship and not as tenants in        Minors Act (State)
            Common

Additional abbreviations, though not in the above list, may also be used.

ASSIGNMENT OF COMMON UNITS
IN
RIO VISTA ENERGY PARTNERS L.P.
IMPORTANT NOTICE REGARDING INVESTOR RESPONSIBILITIES
DUE TO TAX SHELTER STATUS OF
RIO VISTA ENERGY PARTNERS L.P.

You have acquired an interest in Rio Vista Energy Partners L.P., 820 Gessner Road, Suite 1285, Houston, Texas 77024, whose taxpayer identification number is 20-0153267. The Internal Revenue Service has issued Rio Vista Energy Partners L.P. the following tax shelter registration number:

YOU MUST REPORT THIS REGISTRATION NUMBER TO THE INTERNAL REVENUE SERVICE IF YOU CLAIM ANY DEDUCTION, LOSS, CREDIT OR OTHER TAX BENEFIT OR REPORT ANY INCOME BY REASON OF YOUR INVESTMENT IN RIO VISTA ENERGY PARTNERS L.P.

You must report the registration number as well as the name and taxpayer identification number of Rio Vista Energy Partners L.P. on Form 8271. FORM 8271 MUST BE ATTACHED TO THE RETURN ON WHICH YOU CLAIM THE DEDUCTION, LOSS, CREDIT OR OTHER TAX BENEFIT OR REPORT ANY INCOME BY REASON OF YOUR INVESTMENT IN RIO VISTA ENERGY PARTNERS L.P.

If you transfer your interest in Rio Vista Energy Partners L.P. to another person, you are required by the Internal Revenue Service to keep a list containing (a) that person's name, address and taxpayer identification number,
(b) the date on which you transferred the interest and (c) the name, address and tax shelter registration number of Rio Vista Energy Partners L.P. If you do not want to keep such a list, you must (1) send the information specified above to the Partnership, which will keep the list for this tax shelter, and (2) give a copy of this notice to the person to whom you transfer your interest. Your failure to comply with any of the above-described responsibilities could result in the imposition of a penalty under Section 6707(b) or

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6708(a) of the Internal Revenue Code of 1986, as amended, unless such failure is shown to be due to reasonable cause.

ISSUANCE OF A REGISTRATION NUMBER DOES NOT INDICATE THAT THIS INVESTMENT OR THE CLAIMED TAX BENEFITS HAVE BEEN REVIEWED, EXAMINED OR APPROVED BY THE INTERNAL REVENUE SERVICE.

FOR VALUE RECEIVED, ___________________ hereby assigns, conveys, sells and transfers unto

_____________________________________      _____________________________________
(Please print or typewrite name and        (Please insert Social Security or
address  of  Assignee)                     other identifying  number  of
                                           Assignee)

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_________ Common Units representing limited partner interests evidenced by this Certificate, subject to the Partnership Agreement, and does hereby irrevocably constitute and appoint ____________________ as its attorney-in-fact with full power of substitution to transfer the same on the books of Rio Vista Energy Partners L.P.

Date:_________________        NOTE:  The  signature  to  any  endorsement hereon
                              must  correspond with the name as written upon the
                              face  of  this  Certificate  in  every particular,
                              without  alteration,  enlargement  or  change.

SIGNATURE(S) MUST BE GUARANTEED _____________________________________

BY  A  MEMBER  FIRM  OF  THE  NATIONAL     Signature
ASSOCIATION  OF  SECURITIES  DEALERS,
INC.  OR  BY  A  COMMERCIAL  BANK
OR  TRUST  COMPANY  SIGNATURE(S)           _____________________________________
GUARANTEED                                 Signature

No transfer of the Common Units evidenced hereby will be registered on the books of the Partnership, unless the Certificate evidencing the Common Units to be transferred is surrendered for registration or transfer and an Application for Transfer of Common Units has been executed by a transferee either (a) on the form set forth below or (b) on a separate application that the Partnership will furnish on request without charge. A transferor of the Common Units shall have no duty to the transferee with respect to execution of the transfer application in order for such transferee to obtain registration of the transfer of the Common Units.

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APPLICATION FOR TRANSFER OF COMMON UNITS

The undersigned ("Assignee") hereby applies for transfer to the name of the Assignee of the Common Units evidenced hereby.

The Assignee (a) requests admission as a Substituted Limited Partner and agrees to comply with and be bound by, and hereby executes, the Amended and Restated Agreement of Limited Partnership of Rio Vista Energy Partners L.P. (the "Partnership"), as amended, supplemented or restated to the date hereof (the "Partnership Agreement"), (b) represents and warrants that the Assignee has all right, power and authority and, if an individual, the capacity necessary to enter into the Partnership Agreement, (c) appoints the General Partner of the Partnership and, if a Liquidator shall be appointed, the Liquidator of the Partnership as the Assignee's attorney-in-fact to execute, swear to, acknowledge and file any document, including, without limitation, the Partnership Agreement and any amendment thereto and the Certificate of Limited Partnership of the Partnership and any amendment thereto, necessary or appropriate for the Assignee's admission as a Substituted Limited Partner and as a party to the Partnership Agreement, (d) gives the powers of attorney provided for in the Partnership Agreement, and (e) makes the waivers and gives the consents and approvals contained in the Partnership Agreement. Capitalized terms not defined herein have the meanings assigned to such terms in the Partnership Agreement.

Date:_________________________

___________________________________________     ________________________________
Social Security or other identifying number     Signature of Assignee

____________________________________________    ________________________________
Purchase Price including commissions, if any    Name and Address of Assignee

Type of Entity (check one):

[ ] Individual [ ] Partnership [ ] Corporation
[ ] Trust [ ] Other (specify)

Nationality (check one):

[ ] U.S. Citizen, Resident or Domestic Entity
[ ] Foreign Corporation [ ] Non-resident Alien

If the U.S. Citizen, Resident or Domestic Entity box is checked, the following certification must be completed.

Under Section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), the Partnership must withhold tax with respect to certain transfers of property if a holder of an interest in the Partnership is a foreign person. To inform the Partnership that no withholding is

92

required with respect to the undersigned Interestholder's interest in it, the undersigned hereby certifies the following (or, if applicable, certifies the following on behalf of the Interestholder).

Complete Either A or B:

A. Individual Interestholder

1. I am not a non-resident alien for purposes of U.S. income taxation.

2. My U.S. taxpayer identification number (Social Security Number) is ________________________.

3. My home address is ________________________________________________________________.

B. Partnership, Corporation or Other Interestholder

1. ____________________________ is not a foreign corporation, foreign partnership, foreign trust (Name of Interestholder) or foreign estate (as those terms are defined in the Code and Treasury Regulations).

2. The Interestholder's U.S. employer identification number is

3. The Interestholder's office address and place of incorporation (if applicable) is ________________ .

The Interestholder agrees to notify the Partnership within sixty (60) days of the date the Interestholder becomes a foreign person.

The Interestholder understands that this certificate may be disclosed to the Internal Revenue Service by the Partnership and that any false statement contained herein could be punishable by fine, imprisonment or both.

Under penalties of perjury, I declare that I have examined this certification and to the best of my knowledge and belief it is true, correct and complete and, if applicable, I further declare that I have authority to sign this document on behalf of:


Name of Interestholder


Signature and Date


Title (if applicable)

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Note: If the Assignee is a broker, dealer, bank, trust company, clearing corporation, other nominee holder or an agent of any of the foregoing, and is holding for the account of any other person, this application should be completed by an officer thereof or, in the case of a broker or dealer, by a registered representative who is a member of a registered national securities exchange or a member of the National Association of Securities Dealers, Inc., or, in the case of any other nominee holder, a person performing a similar function. If the Assignee is a broker, dealer, bank, trust company, clearing corporation, other nominee owner or an agent of any of the foregoing, the above certification as to any person for whom the Assignee will hold the Common Units shall be made to the best of the Assignee's knowledge.

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RIO VISTA GP LLC
AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT

DATED AS OF SEPTEMBER 16, 2004


THE MEMBERSHIP INTERESTS DESCRIBED IN THIS DOCUMENT HAVE BEEN ACQUIRED FOR INVESTMENT AND HAVE BEEN ISSUED PURSUANT TO A CLAIM OF EXEMPTION FROM THE REGISTRATION OR QUALIFICATION PROVISIONS OF THE SECURITIES ACT OF 1933 OR THE SECURITIES LAWS OF ANY STATE. EXCEPT AS OTHERWISE PROVIDED HEREIN, WITHOUT SUCH REGISTRATION, SAID MEMBERSHIP INTERESTS MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED, EXCEPT ON DELIVERY TO THE COMPANY OF AN OPINION OF COUNSEL SATISFACTORY TO THE BOARD OF MANAGERS OF THE COMPANY THAT REGISTRATION IS NOT REQUIRED FOR THE TRANSFER, OR SUCH OTHER EVIDENCE SATISFACTORY TO THE BOARD OF MANAGERS THAT THE TRANSFER IS NOT IN VIOLATION OF THE SECURITIES ACT OF 1933 OR ANY APPLICABLE STATE SECURITIES LAWS. THE SALE, PLEDGE OR OTHER TRANSFER OF THESE SECURITIES IS ALSO SUBJECT TO THE RESTRICTIONS SET FORTH IN ARTICLE 9 OF THIS DOCUMENT.

RIO VISTA GP LLC

AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT

THIS AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT of Rio Vista

GP LLC is dated as of September 16, 2004.

WHEREAS, the Members wish to enter into this Agreement to provide for, among other things, the management of the business and affairs of the Company, the allocation of profits and losses among the Members, the respective rights and obligations of the Members to each other and to the Company, and certain other matters.

NOW, THEREFORE, the Members agree as follows:

ARTICLE 1
DEFINITIONS

For purposes of this Agreement, certain capitalized terms have specifically defined meanings that are either set forth herein or in Exhibit 1 which is attached hereto and incorporated herein by reference.

ARTICLE 2
FORMATION AND PURPOSE

2.1 Formation. The Company was formed pursuant to the Act and the Members hereby ratify the filing of the Company's Certificate of Formation with the Secretary of State of the State of Delaware on July 10, 2003. This Agreement amends and restates the Limited Liability Company Agreement of the Company dated July 10, 2003, in its entirety. The rights and liabilities of the Members shall be determined pursuant to the Act and this Agreement. To the extent that the rights or obligations of any Member are different by reason of any provision

of this Agreement than they would be in the absence of such provision, this Agreement shall, to the extent permitted by the Act, control.

2.2 Name. The name of the Company is Rio Vista GP LLC. The business of

the Company may be conducted under that name or, upon compliance with applicable laws, any other name that the Board of Managers deems appropriate or advisable. The Board of Managers shall file, or shall cause to be filed, any assumed name certificates and similar filings, and any amendments thereto, that the Board of Managers considers appropriate or advisable.

2.3 Registered Office and Agent. The registered office required to be maintained by the Company in the State of Delaware pursuant to the Act shall initially be located at 615 South DuPont Highway , City of Dover, County of Kent, Delaware 19901. The name and address of the registered agent of the Company pursuant to the Act shall initially be Capitol Services, IncThe Company may, upon compliance with the applicable provisions of the Act, change its registered office or registered agent from time to time at the sole discretion of the Board of Managers.

2.4 Term. The term of the Company shall continue indefinitely unless

terminated as hereinafter provided.

2.5 Purpose. The Company is formed for the object and purpose of, and the nature of the business to be conducted and promoted by the Company is, engaging in any lawful act or activity for which limited liability companies may be formed under the Act and engaging in any and all activities necessary, advisable, convenient or incidental thereto.

2.6 Specific Powers. The Company shall have the power and authority to take any and all actions necessary, appropriate, proper, advisable, incidental or convenient to or for the furtherance of the purpose set forth in Section 2.5.

2.7 Certificate. Richard Shore, Jr. and Ian T. Bothwell are hereby designated as authorized persons to execute, deliver and file any amendments or restatements of the Certificate, and any other certificates and any amendments or restatements thereof necessary for the Company to qualify to do business in a jurisdiction in which the Company may wish to conduct business.

2.8 Ownership of Company Property; Waiver of Partition. All Company property, both real and personal, presently owned or hereafter acquired by the Company, shall be owned by the Company and held in the name of the Company. Each Member expressly waives any right such Member might individually have to require a partition thereof or a dissolution of the Company, except as otherwise specifically provided herein.

ARTICLE 3
COMPANY AND CAPITAL

3.1 Members. The names and addresses of the Members of the Company and each Member's Capital Contribution shall be listed on Schedule I attached to this Agreement, as from time to time amended and supplemented in accordance with the provisions of this Agreement.

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Schedule I lists the Members of the Company, their Capital Contributions, Capital Accounts and the number of Units held by each of them as of the Effective Date.

3.2 Capital Accounts. A separate account (each a "Capital Account") shall be established and maintained for each Member which shall be increased by (a) the amount of cash and the Fair Market Value of any other property contributed by such Member to the Company as a Capital Contribution (net of liabilities secured by such property or that the Company is considered to assume or take the property subject to pursuant to Code Section 752), (b) the services rendered by any Member in the amount that the Company is entitled to take a compensation deduction for federal income tax purposes, (c) such Member's share of the Net Profit of the Company and (d) any amount required pursuant to the terms of any option or other equity incentive agreement entered into by the Company, and shall be reduced by (y) the amount of cash and the Fair Market Value of any other property distributed to such Member (net of liabilities secured by such property or that the Member is considered to assume or take the property subject to pursuant to Code Section 752) and (z) such Member's share of the Net Loss of the Company. It is the intention of the Members that the Capital Accounts of the Company be maintained in accordance with the provisions of Section 704(b) of the Code and the Regulations thereunder and that this Agreement be interpreted consistently therewith.

3.3 Return of Capital Contributions. No Member shall have the right to demand a return of all or any part of its Capital Contributions, and any return of the Capital Contributions to any Member shall be made solely from the assets of the Company and only in accordance with the terms of this Agreement. No interest shall be paid to any Member with respect to its Capital Contributions. Each Member shall look solely to the assets of the Company for the return of its Capital Contributions, and, if the assets of the Company are insufficient to return its Capital Contributions, it shall have no recourse against any other Member for that purpose.

3.4 Additional Members. Except to the extent that the provisions in Article 10 shall have been complied with in connection with a Transfer pursuant to Article 9, no Person shall be admitted as a Member of the Company unless and until the following conditions have been satisfied:

(a) the Board of Managers shall have consented in writing to the admission of such Person as a Member; and

(b) such other instruments, documents, certificates and opinions as the Board of Managers deems necessary or desirable for admission for such Person, including a counterpart of or a joinder to this Agreement, shall have been executed and delivered.

3.5 Units. The Interests of the Members in the Company shall be represented by Units. The Board of Managers may, but is not required to, adopt forms of, and issue to Members, certificates representing the Units. The Units shall be deemed "securities" within the meaning of Section 8-103(c) of the Uniform Commercial Code.

3.6 Management Units. The Board of Managers may from time to time in its sole discretion (a) issue Units, or reserve Units to be issued upon the exercise of options granted, to

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employees, consultants, managers or independent contractors of the Company or its Affiliates, whether in connection with an investment by such Person or otherwise, and (b) issue options to purchase Units pursuant to the Company's Unit option plans or otherwise to employees, consultants, managers or independent contractors of the Company or its Affiliates, or other Persons the Board of Managers deems appropriate, all upon terms, conditions, vesting rights and consideration, if any, as the Board of Managers deems appropriate; provided, however, that the aggregate number of Units issued or reserved for options pursuant to this Section 3.6 shall at no time exceed 10,000 Units. The terms on which any Units are issued pursuant to this Section 3.6 shall be determined by the Board of Managers.

3.7 Additional Units; Other Securities. In addition to Units permitted to be issued under Section 3.6, the Board of Managers, subject to the terms and conditions of this Section 3.7, may issue additional Units after the Effective Date to such Persons (including but not limited to the Members or their Affiliates) and for such consideration as the Board of Managers deems appropriate in accordance with and subject to the terms of this Agreement. The terms and conditions of any Units issued pursuant to this Section 3.7 shall be determined by the Board of Managers and such Units may consist of one or more classes of Units possessing unique rights and preferences. The Board of Managers is also authorized to cause the issuance of any other type of security of the Company from time to time on terms and conditions established at the discretion of the Board of Managers. Such securities may specifically include, without limitation, unsecured and secured debt obligations of the Company, debt obligations of the Company convertible into Units, options or warrants to purchase any Units or any combination of any of the foregoing. The Board of Managers shall do all things necessary to comply with the Act and is authorized and directed to do all things it deems necessary or advisable in connection with any such future issuance of Units, including compliance with any statute, rule, regulation or guideline of any federal, state or other governmental agency.

3.7.1 Preemptive Rights. The Company hereby grants to each holder of Units the preemptive right to purchase up to its pro rata share of New Securities (as defined in this Section 3.7.1) which the Company may, from time to time, propose to sell and issue. A Unitholder's pro rata share, for purposes of this preemptive right, is the ratio of the number of Units owned by such Unitholder immediately prior to the issuance of New Securities, assuming exercise of any convertible securities, rights, options or warrants to acquire Units of the Company held by said holder, to the total number of Units outstanding immediately prior to the issuance of New Securities (minus any Units held by Management Members excluded pursuant to Section 3.7.1(e)), assuming exercise of all outstanding convertible securities, rights, options and warrants to acquire Units of the Company.

(a) "New Securities" shall mean any Units of the Company and rights, options or warrants to purchase such Units, and securities of any type whatsoever that are convertible into Units; provided that the term "New Securities" does not include (i) issuances pursuant to Section 3.6; (ii) any issuance of additional Units to all holders of Units as a distribution thereon, pro rata; (iii) any issuance of securities pursuant to the acquisition of a business entity or business segment of such business entity, in each case not Affiliated with the Company, by the Company by merger, consolidation,

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conversion, reorganization, purchase of shares, purchase of substantially all of the assets, or similar transaction; (iv) any issuance to vendors, customers, suppliers, universities, consultants, financial advisors or to other persons in similar commercial situations with the Company, in each case which are not Affiliated with the Company; (v) any issuance of securities in connection with obtaining lease or other debt financing or other borrowings, whether issued to a financial institution, lessor, guarantor or any other Person (collectively, "Equity Kickers"); provided, however, with respect to the issuance of an Equity Kicker to a Member or its Affiliate, the foregoing exclusion to the definition of New Securities shall only apply if, in connection with a transaction to which Section 3.7.2 applies, Section 3.7.2 has been complied with; (vi) any issuance in connection with partnering transactions, joint venture arrangements or acquiring a product or service in each case involving a party not Affiliated with the Company or any of its Members; (vii) issuance of securities upon the exercise or conversion of any security issued in compliance with Section 3.7; and (viii) any right, option or warrant to acquire any security convertible into the securities included in subsections (i) through (vii) above.

(b) In the event the Company proposes to undertake an issuance of New Securities, the Board of Managers shall give each holder of Units written notice of its intention describing the type of New Securities and their price and the general terms upon which the Company proposes to issue the same. Each such holder of Units shall have 30 days after any such notice is mailed to agree to purchase all or any portion of such Unitholder's pro rata share of such New Securities for the price and upon the terms specified in the notice by giving written notice to the Board of Managers and stating therein the quantity of New Securities to be purchased.

(c) In the event such holder of Units fails to exercise its preemptive right pursuant to Section 3.7.1(b) within said 30 day period, the Company shall have 120 days thereafter to sell the New Securities respecting which the Unitholder's preemptive right option set forth in this Section 3.7.1 was not exercised, at a price and upon terms no more favorable to the purchasers thereof than specified in the Board of Managers' notice to Unitholders pursuant to Section 3.7.1(b). In the event the Company has not sold the New Securities within such 120 day period, the Company shall not thereafter issue or sell any New Securities without first again offering such securities to the Unitholders in the manner provided in Section 3.7.1(b) above.

(d) The preemptive right granted under this Agreement shall expire upon, and shall not be applicable to, any sale of Units of the Company to the public effected pursuant to a registration statement filed with, and declared effective by, the Securities and Exchange Commission under the Securities Act.

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3.7.2 Loans, Advances and Guarantees.

(a) In the event that the Board of Managers determines in its sole discretion that the Company requires funds, the Board of Managers shall be authorized, at any time and from time to time, to cause the Company to borrow additional funds sufficient for such purposes and upon such terms as the Board of Managers may deem appropriate. Moreover, the Board of Managers shall be authorized to permit one or more Members or their Affiliates to guaranty any such borrowed funds. In addition, the Board of Managers shall be authorized to issue Equity Kickers in connection with borrowing of funds or guarantees.

(b) Any such loans and guarantees may be provided by third parties or by one or more Members or their Affiliates. Any loan or guaranty provided by a Member shall not be considered contributions to the capital of the Company and shall not increase the Capital Account of the lending or guarantying Member.

(c) If the Board of Managers desires to request a loan or a several but not joint guaranty from the Members (or any Member or their Affiliates), it shall give the Members written notice of such request, which notice shall include, with respect to any loan, the amount, interest rate, priority and repayment terms with respect to other indebtedness of the proposed loan and, with respect to a several but not joint guaranty, the terms upon which such guaranty will be given (and in both cases details of any proposed Equity Kicker associated therewith). The Members shall have 30 days from receipt of such notice to elect to make all or a portion of the requested loan or a several but not joint guaranty (and receive a pro rata portion of the associated Equity Kicker) in the amounts mutually agreed upon by the Board of Managers and the participating Members. Unless otherwise agreed by the participating Members, any loan or a several but not joint guaranty made by the participating Members to the Company (and any associated Equity Kicker) will be made pro rata among the participating Members in accordance with their respective ownership of Units then outstanding. Notice of any such election to participate shall be given to the Board of Managers within such 30 day period; failure to timely respond shall be deemed to be a decision by a Member that it does not desire to participate in such guaranty, loan or advance. The interest accruing on any such resulting loan and the expenses of such loan or guaranty, including any origination fee, shall be paid and charged as an expense of the Company. For each loan made by a lending Member to the Company, the Company shall execute a note payable to the lending Member, upon the terms, priority with respect to other indebtedness and in the principal sum determined by the Board of Managers and the lending Member. For each guaranty made by a guarantying Member on behalf of the Company, the Company shall execute a reimbursement agreement in

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favor of the guarantying Members on the terms determined by the Board of Managers and the guarantying Members.

(d) Notwithstanding the foregoing, Management Members shall not have the right to participate in the loans or guarantees contemplated in this Section 3.7.2, unless expressly so permitted by the Board

of Managers.

3.8 Issuance Notice. The Board of Managers shall promptly prepare a revised Schedule I, which shall be deemed to replace the old Schedule I and constitute an amendment of this Agreement approved by all of the Members, to reflect the issuance after the Effective Date of additional Units pursuant to
Section 3.6 or 3.7. The Board of Managers shall give notice to all the Members promptly after the issuance of additional Units pursuant to Section 3.6 or 3.7 informing the Members of such issuance or redemption and the revised number of Units issued and outstanding following such issuance, and enclosing a copy of Schedule I hereto, as revised to reflect such transaction. The revised Schedule
I shall also set forth Capital Contributions, if any, made in consideration for

such Units.

3.9 Preemptive Rights. Other than as set forth in this Agreement, no Unitholder shall have any preemptive right with respect to (a) additional Capital Contributions to the Company, (b) the issuance or sale of Units or other interests in the Company, (c) the issuance of any obligation, evidence of indebtedness or other interest of or in the Company convertible into or exchangeable for, or carrying or accompanied by any rights to receive, purchase or subscribe to, any Units, (d) the issuance or any right of subscription to, or right to receive, any warrant or option for the purchase of any Units, or (e) the issuance or sale of any other securities that may be issued or sold by the Company.

ARTICLE 4
STATUS OF MEMBERS

4.1 Limited Liability. No Member shall be bound by or personally liable for the expenses, liabilities, or obligations of the Company arising in contract, tort or otherwise, each of which is solely an obligation of the Company. The Members shall not be required to make any additional contributions to the Company. In no event shall any Member be required to make up any deficit balance in such Member's Capital Account upon the liquidation of the Company or otherwise. Except as provided in this Agreement, no Members shall be personally liable, directly or indirectly, by way of indemnification, contribution, assessment, or otherwise for an obligation solely by reason of being or acting as a Member.

4.2 Return of Distributions of Capital. Except as otherwise expressly required by law, a Member, in its capacity as such, shall have no liability for obligations or liabilities of the Company in excess of (a) the amount of its Capital Contributions actually made to the Company, (b) its share of any assets and undistributed profits of the Company, and (c) to the extent required by the Act, the amount of any Distributions wrongfully distributed to it. Except as required by the Act, no Member shall be obligated by this Agreement to return any Distribution to the Company or pay the amount of any Distribution for the account of the Company or to any creditor of the Company. However, if any court of competent jurisdiction holds that, notwithstanding the provisions of this Agreement, any Member is obligated to return or pay any

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part of any Distribution, the obligation shall be that of such Member alone and not of any Manager or any other Member. The amount of any Distribution returned to the Company by a Member or paid by a Member for the account of the Company or to a creditor of the Company shall be added to the account or accounts from which it was subtracted when it was distributed to the Member.

ARTICLE 5
DESIGNATION, RIGHTS, AUTHORITIES, POWERS,
RESPONSIBILITIES, AND DUTIES OF THE BOARD OF MANAGERS

5.1 Management by Board of Managers. Subject to the provisions of the Act and any limitations in this Agreement as to action to be authorized or approved by the Members, all management powers over the business and affairs of the Company shall be exclusively vested in a board of managers (the "Board of Managers"). Collectively, members of the Board of Managers (each, a "Manager")
shall constitute "managers" of the Company within the meaning of the Act. The Board of Managers on the Effective Date shall be the Persons set forth in Exhibit 5.1 hereto. The Board of Managers may delegate certain of its powers to officers (the "Officers"), who shall be agents of the Company. The Members, by virtue of their status as members of the Company, shall not have any management power over the business and affairs of the Company or actual or apparent authority to enter into contracts on behalf of, or to otherwise bind, the Company. Except as otherwise specifically provided in this Agreement, the authority and functions of the Board of Managers and of the Officers shall be identical to the authority and functions of the board of directors and officers, respectively, of a corporation organized under the Delaware General Corporation Law. Thus, except as otherwise specifically provided in this Agreement, the business and affairs of the Company shall be managed under the direction of the Board of Managers, and the day-to-day activities of the Company shall be conducted on the Company's behalf by the Officers. In addition to the powers that now or hereafter can be granted to managers under the Act and to all other powers granted under any other provision of this Agreement, the Board of Managers (subject to Section 5.2 of this Agreement) and the Officers (subject to Section 5.3 of this Agreement and the direction of the Board of Managers) shall have full power and authority to do all things on such terms as they, in their Sole Discretion, may deem necessary or appropriate to conduct, or cause to be conducted, the business and affairs of the Company.

5.2 Board of Managers.

(a) Number and Term.

The Board of Managers shall consist of a number of Managers determined by a Majority Interest from time to time; provided; that the Board of Managers may not consists of less than three Managers. Managers need not be Members. Except as otherwise provided in Section 5.2(d), each Manager shall be elected at the annual meeting of the Members, and the individuals receiving the most votes at such meeting shall be elected. No decrease in the number of Managers shall have the effect of shortening the term of office of any incumbent Manager.

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(b) Chairman.

The Board of Managers shall select one Manager to serve as the Chairman of the Board of Managers, and the Board of Managers shall elect one other Manager to be the Vice Chairman. The Chairman shall preside at all meetings of the Members and the Board of Managers. The Vice Chairman shall perform all the duties of the Chairman in the absence or disability of the Chairman. The Chairman and Vice Chairman shall have such other powers and perform such other duties as may be prescribed from time to time by the Board of Managers.

(c) Quorum and Manner of Action.

At all meetings of the Board of Managers, a majority of the total number of Managers shall constitute a quorum for the transaction of business; and the act of a majority of the Managers present at any meeting at which there is a quorum shall be the act of the Board of Managers, except as otherwise provided by Law or this Agreement. If at any meeting of the Board of Managers there shall be less than a quorum present, a majority of those present may adjourn the meeting from time to time until a quorum is obtained, and no further notice thereof need be given other than by announcement at such adjourned meeting. Attendance by a Manager at a meeting shall constitute a waiver of notice of such meeting except where a Manager attends a meeting for the express purpose of objecting, at the beginning of the meeting, to the transaction of any business on the ground that the meeting is not lawfully called or convened.

(d) Vacancies.

Except as otherwise provided by law or this Agreement, in the case of any increase in the authorized number of Managers or of any vacancy in the Board of Managers, however created, the additional Manager or Managers may be elected or, as the case may be, the vacancy or vacancies may be filled by majority vote of the Managers remaining on the whole Board of Managers although less than a quorum, or by a sole remaining Manager. Any Manager elected or chosen as provided herein shall serve until the first to occur of (i) the expiration of the term to which such Manager is elected or appointed, (ii) the election and qualification of the Manager's successor, or (iii) the Manager's resignation or removal.

(e) Resignations.

A Manager may resign at any time upon written notice of resignation to the Company. Any resignation shall be effective immediately unless a certain effective date is specified therein, in which event it will be effective upon such date and acceptance of any resignation shall not be necessary to make it effective.

(f) Removals.

Any Manager or the entire Board of Managers may be removed, with or without cause, and another person or persons may be elected to serve for the remainder of his or their term by a Majority Interest. In case any vacancy so created shall not be filled by the

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Members, such vacancy may be filled by the remaining Managers as provided in Section 5.2(d).

(g) Annual Meetings.

The annual meeting of the Board of Managers shall be held, if a quorum be present, for the purpose of organization and transaction of any business that might be transacted at a regular meeting thereof, and no notice of such meeting shall be necessary. If a quorum is not present, such annual meeting may be held at any other time or place that may be specified in a notice given in the manner provided in Section 5.2(i) for special meetings of the Board of Managers or in a waiver of notice thereof.

(h) Regular Meetings.

Regular meetings of the Board of Managers may be held without notice at such places and times as shall be determined from time to time by resolution of the Board of Managers. Except as otherwise provided by law or this Agreement, any business may be transacted at any regular meeting of the Board of Managers.

(i) Special Meetings.

Special meetings of the Board of Managers may be called by the Chief Executive Officer, or shall be called by the Secretary on the written request of any Manager stating the purpose or purposes of such meeting. Notices of special meetings shall be given to each Manager not later than three days before the day the meeting is to be held. No notice of any meeting need be given to any Manager who files a written waiver of notice thereof with the Secretary either before or after the meeting. Neither the business to be transacted at, nor the purpose of, any special meeting need be specified in any notice or written waiver of notice, unless so required by this Agreement. Except as otherwise provided by Law or this Agreement, any and all business may be transacted at a special meeting.

(j) Organization of Meetings.

At any meeting of the Board of Managers, business shall be transacted in such order and manner as the Chairman may from time to time determine.

(k) Place of Meetings.

The Board of Managers may hold their meetings at any office or offices of the Company, or at any other place as they may from time to time by resolution determine.

(l) Compensation of Managers; Reimbursement of Expenses.

The Managers shall not receive any compensation for their services. Managers shall be reimbursed by the Company for their reasonable traveling, food, lodging and other expenses incurred in attending meetings in accordance with policies approved from time to time by the Board of Managers.

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(m) Action by Written Consent.

Unless otherwise restricted by Law or this Agreement, any action required or permitted to be taken at any meeting of the Board of Managers may be taken without a meeting if the required number of such Managers consent thereto in writing and the writing or writings are filed with the minutes of proceedings of the Board of Managers. If any action is taken by written consent to which less than all of the Managers have consented, the consenting Managers shall promptly provide notice of such action to the other Managers.

(n) Participation in Meetings by Telephone.

The Managers may participate in a meeting of the Board of Managers by means of conference telephone or similar communications equipment by means of which all persons participating in the meeting can hear each other, and participation in a meeting in such manner shall constitute presence in person at such meeting.

5.3 Officers; Agents. The Board of Managers by resolution or vote of the Board of Managers shall have the power to appoint agents (who may be referred to as officers) to act for the Company with such titles, if any, as the Board of Managers deems appropriate and to delegate to such officers or agents such of the powers as are granted to the Board of Managers hereunder, including the power to execute documents on behalf of the Company, as the Board of Managers may in its sole discretion determine. The officers or agents so appointed may include persons holding titles such as Chief Executive Officer, President, Executive Vice President, Vice President, Chief Operating Officer, Chief Financial Officer, Treasurer or Controller. Unless the authority of the agent designated as the officer in question is limited in the document appointing such officer or is otherwise specified by the Board of Managers, any officer so appointed shall have the same authority to act for the Company as a corresponding officer of a Delaware corporation would have to act for a Delaware corporation in the absence of a specific delegation of authority and as more specifically set forth herein; provided, however, that unless such power is specifically delegated to the officer in question either for a specific transaction or generally, no such officer shall have the power to lease or acquire real property, to borrow money, to issue notes, debentures, securities, equity or other interests of or in the Company, to make investments in (other than the investment of surplus cash in the ordinary course of business) or to acquire securities of any Person, to give guarantees or indemnities, to merge, liquidate or dissolve the Company or to sell or lease all or any substantial portion of the assets of the Company. The Board of Managers, in its sole discretion, may by vote or resolution of the Board of Managers ratify any act previously taken by an officer or agent acting on behalf of the Company.

5.3.1 Officers. Officers and agents of the Company, if any, shall be appointed by the Board of Managers from time to time in its discretion. An officer may be but none need be a Member or Manager. Any two or more offices may be held by the same person. Any officer may be required by the Board of Managers to secure the faithful performance of the officer's duties to the Company by giving bond in such amount and with sureties or otherwise as the Board of Managers may determine.

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5.3.2 Designations and Delegations. Officers may be designated by the Board of Managers at any time. At any time or from time to time the Board of Managers may delegate to any officer their power to elect or appoint any other officer or any agents.

5.3.3 Tenure. Each officer shall retain its authority at the pleasure of the Board of Managers, or the officer by whom such officer was appointed or by the officer who then holds agent appointive power.

5.3.4 Resignation; Removal; Vacancies. Any officer or agent may resign by delivering a written letter of resignation to the Chairman, if any, the President, the Secretary or to the Board of Managers, which resignation shall not require acceptance and, unless otherwise specified in the letter of resignation, shall be effective upon receipt. The Board of Managers or the officer appointing the officer or agent may remove any officer or agent at any time without giving any reason for such removal and no officer or agent shall be entitled to any damages by virtue of such officer's removal from office or such position as agent. If any office becomes vacant, the position may be filled by the Board of Managers or in such other manner as the officer in question was appointed.

5.3.5 President and Vice Presidents. Unless the Board of Managers otherwise specifies, the President shall be the chief executive officer and shall have direct charge of all business operations of the Company and, subject to the control of the Board of Managers, shall have general charge and supervision of the business of the Company. Any vice presidents shall have duties as shall be designated from time to time by the Board of Managers or the President.

5.3.6 Treasurer and Assistant Treasurers. Unless the Board of Managers otherwise specifies, the Treasurer shall be the chief financial officer of the Company and shall be in charge of its funds and valuable papers, and shall have such other duties and powers as may be designated from time to time by the Board of Managers or the President. Any Assistant Treasurers shall have such duties and powers as shall be designated from time to time by the Board of Managers, the President or the Treasurer.

5.3.7 Secretary and Assistant Secretaries. The Secretary shall record all proceedings of the Members and the Board of Managers in a book or series of books to be kept therefor and shall file therein all actions by written consent of the Board of Managers. In the absence of the Secretary from any meeting, an Assistant Secretary, or if there be none or no Assistant Secretary is present, a temporary secretary chosen at the meeting, shall record the proceedings thereof. The Secretary shall keep or cause to be kept records, which shall contain the names and record addresses of all Members. The Secretary shall have such other duties and powers as may from time to time be designated by the Board of Managers or the President. Any Assistant Secretaries shall have such duties and powers as shall be designated from time to time by the Board of Managers, the President or the Secretary.

5.4 Right of Third Parties to Rely on Authority of Board of Managers.
Notwithstanding any other provision of this Agreement to the contrary, no lender or purchaser of Company assets shall be required to verify any representation by the Board of Managers or any

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officer of the Company duly authorized by resolution of the Board of Managers as to the extent of the interest in the assets of the Company which the Board of Managers is entitled to encumber, sell or otherwise use, and any such lender or purchaser shall be entitled to rely exclusively on the representations of the Board of Managers or any officer of the Company duly authorized by resolution of the Board of Managers as to its individual authority to enter into such financing or sale arrangements and shall be entitled to deal with the Board of Managers or any officer of the Company duly authorized by resolution of the Board of Managers as if they were the sole party in interest therein both legally and beneficially.

5.5 Certain Limitations on Board of Managers and Members Activities.

5.5.1 Unanimous Consent Required. Notwithstanding any provision in this Agreement to the contrary, the Board of Managers and Members shall not do any of the following, and none of the following shall be an act of the Board of Managers or the Members, without, in each instance, obtaining the consent of all of the Members:

(a) effect or cause to be effected any Transfer (including any indirect Transfer by way of a Sale of the Company) of the Incentive Distribution Rights (as defined in the First Amended and Restated Agreement of Limited Partnership of Rio Vista Energy Partners L.P.) owned or subsequently acquired by the Company; and

(b) take any action to amend or modify any of the provisions of this
Section 5.5.1 or any other provision of this Agreement that would affect the provisions, applicability or effect of this Section 5.5.1 in any way.

5.5.2 Supermajority Consent Required. The Board of Managers shall not do any of the following without, in each instance, obtaining the consent of the Members holding 75% of the Units:

(a) do any act in contradiction of this Agreement;

(b) do any act which would make it impossible to carry on the ordinary business of the Company (except for a disposition of Company assets);

(c) confess a judgment against the Company; or

(d) possess Company assets, or assign the rights in specific Company assets for other than a Company purpose.

5.6 Transactions with the Members or Affiliates. The Company is expressly permitted to enter into transactions, agreements or modifications to transactions or agreements with any Member or any Affiliates thereof or of the Company, provided that such transactions, agreements or modifications to transactions or agreements are (a) on terms taken as a whole not less favorable to the Company than the terms taken as a whole which could reasonably be obtained (as determined in good faith by the Board of Managers) from an unrelated party, or (b) approved by the affirmative vote of a majority of the disinterested members of the Board of Managers, even though the disinterested members may not constitute a quorum.

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5.7 Specific Limitations. Except as provided in this Agreement, no Member shall have the right or power to: (a) withdraw or reduce its Capital Contribution except as provided by law, (b) make voluntary Capital Contributions or contribute any property to the Company other than cash, (c) bring an action for partition against the Company or any Company assets, (d) cause the termination and dissolution of the Company, or (e) upon the return of its Capital Contribution require that property other than cash be distributed in return for its Capital Contribution. Each Member hereby irrevocably waives any and all rights that it may have to maintain an action for partition of any of the Company's property. Except as otherwise set forth in this Agreement, no Member shall have priority over any other Member either as to the return of its Capital Contribution or as to Net Profit, Net Loss, or Distributions. Other than upon the termination and dissolution of the Company as provided by this Agreement, there has been no time agreed upon when or if all or any portion of the Capital Contribution of any Member will be returned.

5.8 Meetings of Members.

(a) Annual Meetings.

Annual meetings of the Members may be held on such date and at such time as shall be determined by the Board of Managers. Notice of the establishment of such annual meeting, and of any amendments thereto, shall be given to each Member at least 10 Days prior to the next annual meeting. No other notices of such annual meetings need be given.

(b) Special Meetings.

Special meetings of the Members may be called by any Member. Any such meeting shall be held on such date and at such time as the Member calling such meeting shall specify in the notice of the meeting, which shall be delivered to each other Member at least 10 Days prior to such meeting. Neither the business to be transacted at, nor the purpose of, such special meeting need be specified in the notice (or waiver of notice) of such meeting.

(c) Quorum.

A Majority Interest (represented either in person or by proxy) shall constitute a quorum for the transaction of business at any meeting of the Members. With respect to any matter, except any matter requiring the consent of all the Members under Section 5.5.1, an act of a Majority Interest shall be the act of the Members. Each Member may, with respect to any vote, consent or approval that he is entitled to grant pursuant to this Agreement, grant or withhold such vote, consent or approval in his Sole Discretion.

(d) Place of Meeting.

Any meeting of the Members shall be held at the principal place of business of the Company, unless the notice of such meeting specifies a different place.

(e) Waiver of Notice Through Attendance.

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Attendance of a Member at any meeting shall constitute a waiver of notice of such meeting, except where such Member attends the meeting for the express purpose of objecting to the transaction of any business on the ground that the meeting is not lawfully called or convened.

(f) Proxies.

A Member may vote at any meeting by a written proxy executed by that Member and delivered to another Member. A proxy shall be revocable unless it is stated to be irrevocable.

(g) Action by Written Consent.

Any action required or permitted to be taken at such meeting may be taken without a meeting, without prior notice, and without a vote if a consent or consents in writing, setting forth the action so taken, is signed by a Majority Interest. The Company shall give prompt written notice to the non-consenting Members of any action of Members taken by less than unanimous written consent of the Members.

(h) Meetings by Telephone.

The Members may participate in and hold any meeting by means of conference telephone, video conference or similar communications equipment by means of which all Persons participating in the meeting can hear each other.

ARTICLE 6
BOOKS, RECORDS, ACCOUNTING AND REPORTS

6.1 Books and Records. The Company shall maintain at its principal office all of the following:

(a) a current list of the full name and last known address of each Member together with information regarding the amount of cash and a description and the Book Value of any other property or services contributed by each Member and which each Member has agreed to contribute in the future, and the date on which each Member became a Member of the Company;

(b) a copy of the Certificate and this Agreement, including any and all amendments to either thereof, or any amendments that have been executed;

(c) copies of the Company's federal, state, and local income tax or information returns and reports, if any, for each taxable year after the Effective Date, provided that the Company need not retain any such records for more than four fiscal years;

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(d) the financial statements of the Company for each Fiscal Year after the Effective Date, provided that the Company need not retain any such records for more than four fiscal years; and

(e) the Company's books and records for each Fiscal Year after the Effective Date, provided that the Company need not retain any such records for more than four fiscal years.

6.2 Delivery to Member, Inspection, etc. Upon the request of any Member, for any purpose reasonably related to such Member's interest as a Member of the Company, the Board of Managers shall cause to be delivered to the requesting Member, at the expense of the Company, a copy of the information required to be maintained by clauses (a) through (e) of Section 6.1. A Member upon reasonable request may inspect at the Company's offices the Company's books and records during reasonable business hours.

6.3 Financial Statements. The Board of Managers shall cause books of account to be maintained reflecting the operations of the Company on an annual basis and shall cause to be prepared for and delivered to the Members at least annually, at the Company's expense, financial statements of the Company prepared in accordance with generally accepted accounting principles.

6.4 Filings. At the Company's expense the Board of Managers shall cause the income tax returns for the Company to be prepared and timely filed with the appropriate authorities and to have prepared and to furnish to each Member such information with respect to the Company as is necessary to enable the Members to prepare their federal and state income tax returns. The Board of Managers, at the Company's expense, shall also cause to be prepared and timely filed, with appropriate federal and state regulatory and administrative bodies, all reports required to be filed by the Company with those entities under then current applicable laws, rules, and regulations. The reports shall be prepared on the accounting or reporting basis required by the regulatory bodies.

6.5 Nondisclosure. Each Member agrees that, except as otherwise consented to by the Board of Managers, all nonpublic information furnished to it pursuant to this Agreement or otherwise with respect to the Company will be kept confidential and will not be disclosed by such Member, or by any of its agents, representatives, or employees, in any manner whatsoever, in whole or in part, except that (a) each Member shall be permitted to disclose such information to those of its agents, representatives, and employees who need to be familiar with such information in connection with such Member's investment in the Company and who are charged with an obligation of confidentiality, (b) each Member shall be permitted to disclose such information to financial institutions, investment bankers and prospective purchasers and capital investors, (c) each Member shall be permitted to disclose such information to its partners and stockholders or to prospective purchasers or Assignees of its Units so long as each of them agree to keep such information confidential on the terms set forth herein, (d) each Member shall be permitted to disclose information to the extent required by law, so long as such Member shall have first afforded the Company with a reasonable opportunity to contest the necessity of disclosing such information, and (e) each Member shall be permitted to disclose information to

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the extent necessary for the enforcement of any right of such Member arising under this Agreement.

ARTICLE 7
DISTRIBUTIONS AND ALLOCATIONS OF PROFIT AND LOSS

7.1 Board of Managers' Determination. The Board of Managers shall have the sole authority to determine the timing and the aggregate amount of any Distributions to Members.

7.2 Distributions. Subject to Section 7.1, Distributions from the Company to its Members shall be made as follows:

7.2.1 If the Company expects that as of the end of any Tax Estimation Period the Company will have Adjusted Taxable Income, then the Company shall distribute to each Member on or before the 15th day after the end of the Tax Estimation Period cash in an amount equal to the Company's estimate of the Adjusted Taxable Income allocable to each such Member during such Tax Estimation Period multiplied by the Combined Effective Marginal Tax Rate. On or before April 15th of each year the Company shall adjust the distributions pursuant to this Section 7.2.1 with respect to the previous Fiscal Year to conform with the Company's income tax returns for such Fiscal Year. Tax Distributions made pursuant to this Section 7.2.1 shall not be deemed to constitute an advance against any distributions provided for in Section 7.2.2 below. In the event that the proportion of the Company's Adjusted Taxable Income allocable to a Member is greater than the proportion of the Company's Net Profit or Net Loss allocable to the Member for the same period, the Tax Distributions to such Member shall reflect the Adjusted Taxable Income allocable to that Member and the Tax Distributions to the other Members shall be adjusted so that Tax Distributions under this
Section 7.2.1 are made in proportion to Unit ownership.

7.2.2 The Company shall make all remaining Distributions to the holders of Units in proportion to their Unit ownership.

7.3 No Violation. Notwithstanding any provision to the contrary contained in this Agreement, the Company, and the Board of Managers on behalf of the Company, shall not be required to make a Distribution to any Member on account of its interest in the Company if such Distribution would violate applicable law.

7.4 Withholding. All amounts withheld pursuant to the Code or any provision of any state, local or foreign tax law with respect to any payment, distribution, or allocation to the Company shall be treated as amounts paid to the Company. Such amounts shall in turn be allocated to and treated as distributed to the Members for all purposes under this Agreement. The Board of Managers is authorized to withhold from Distributions to the Members and to pay over to the appropriate federal, state, local or foreign government any amounts required to be so withheld. The Board of Managers shall allocate any such amounts to the Members in respect of whose Distribution or allocation the tax was withheld and shall treat such amounts as actually distributed to such Members.

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7.5 Property Distributions. If any assets of the Company shall be distributed in kind pursuant to this Article 7, such assets shall be distributed to the Members entitled thereto in the same proportions as the Members would have been entitled to cash Distributions. The amount by which the Fair Market Value of any property to be distributed in kind to the Members exceeds or is less than the Book Value of such property shall, to the extent not otherwise recognized by the Company, be taken into account in determining Net Profit and Net Loss and determining the Capital Accounts of the Members as if such property had been sold at its Fair Market Value immediately prior to the Distribution.

7.6 Allocations of Net Profit or Net Loss. Subject to Section 7.7.2,
7.7.3 and 7.7.4 hereof, the Net Profit or Net Loss of the Company shall be allocated among the Members so as to ensure, to the extent possible, that the Capital Accounts of the Members as of the end of each Fiscal Year reflect the aggregate Distributions that the Members would be entitled to receive if all of the assets of the Company were sold for their Book Values and the proceeds were distributed as of the end of such Fiscal Year in accordance with Section 7.2.2.

7.7 Other Capital Account and Income Tax Adjustments. Prior to making the allocations of Net Profit or Net Loss for the Fiscal Year in accordance with
Section 7.6 hereof, the Board of Managers shall allocate income, gain, loss, deduction and credit (and items thereof) in accordance with the provisions of this Section 7.7 to the extent required by the Code and applicable Regulations.

7.7.1 Certain Contributions of Property. In the event there is a difference between the Book Value at which any property is accepted as a contribution to the capital of the Company (or deemed accepted pursuant to Regulation Section 1.704-1 (b)(2)(iv)(g)) and the adjusted tax basis of such property to the Company, the Board of Managers shall, solely for federal income tax purposes (and not for purposes of allocating Net Profit or Net Loss under Section 7.6 or computing Net Profit or Net Loss), specially allocate the income, gain, loss and deduction attributable to such property to the extent required by Section 704(c) of the Code or any applicable Regulations under Code Section 704(b) or 704(c) using the traditional method under Regulation Section 1.704-3(b).

7.7.2 Certain Adjustments. To the extent that an adjustment to the adjusted tax basis of any Company asset is required pursuant to Section
732(d), Section 734(b) or Section 743(b) of the Code, adjustments to the Capital Accounts shall be made as required pursuant to Regulation Section 1.704-1(b)(2)(iv)(m).

7.7.3 Nonrecourse Deductions; Member Nonrecourse Deductions; Qualified Income Offset, etc. There are hereby included in the Agreement such provisions governing the allocation of taxable income, gain, loss, deduction and credit (and items thereof) determined under the Code as may be necessary to provide that the Company's allocation provisions contain a so-called "Qualified Income Offset" and comply with all provisions relating to the allocation of so-called "Nonrecourse Deductions" and "Member Nonrecourse Deductions" and the chargeback thereof as set forth in the Regulations under Section 704(b) of the Code; provided, however, that the incorporation of such provisions shall affect only the computation of taxable net income and loss and the allocation thereof as between Members and shall not otherwise affect the amount or

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timing of any distribution of cash or property to any Member provided for in this Agreement. Allocations of Nonrecourse Deductions shall be made ratably among the Members in accordance with the number of Units held by the Members. Allocations of Member Nonrecourse Deductions shall be made in accordance with Regulation Section 1.704-2(i).

7.7.4 Limitation on Loss Allocation. Notwithstanding any other provision of this Agreement to the contrary, no item of loss or deduction of the Company shall be allocated to any Member if such allocation would cause such Member to have an Adjusted Capital Account Deficit or would increase such Member's Adjusted Capital Account Deficit. Such loss shall be allocated among the Members in accordance with their interest in the Company as determined under Regulation Section 1.704-1(b)(3); provided, however, that the Board of Managers will notify the Members of any material loss allocation required under this sentence at least 30 days prior to the date on which any Company return is filed reporting such loss and will provide the Members with the proposed allocation and supporting calculations, all in reasonable detail.

7.8 Changes in Members' Units. If during any Fiscal Year of the Company there is a change in any Member's Units in the Company, the Board of Managers shall confer with the tax advisors to the Company and, in conformity with such advice, allocate the Net Profit or Net Loss to the Members so as to take into account the varying interests of the Members in the Company in a manner that complies with the provisions of Section 706 of the Code and the Regulations thereunder.

7.9 Adjustment of Capital Accounts. Unless the Board of Managers shall determine otherwise, the Book Values of all the Company's assets shall be adjusted to equal their respective gross fair market values, as determined by the Board of Managers (and the Capital Accounts of the Members shall be adjusted accordingly), as of the following times: (a) the acquisition of additional Units by any new or existing Member in exchange for more than a de minimis additional Capital Contribution, services rendered or to be rendered or the exercise of an option to acquire such Units; (b) the distribution by the Company to a Member of more than a de minimis amount of assets of the Company as consideration for Units; and (c) the liquidation of the Company; provided, however, that adjustments pursuant to clauses (a) and (b) above shall be made only if the Board of Managers reasonably determines that such adjustments are necessary or appropriate to reflect the relative economic interests of the Members in the Company.

7.10 Allocations for Tax and Section 704(b) Book Purposes. Except as otherwise provided herein, any allocation, for purposes of maintaining Capital Accounts, to a Member for a Fiscal Year or other period of a portion of Net Profit or Net Loss (or of a specially allocated item) shall be determined to be an allocation to that Member of the same proportionate part of each item of income, gain, loss, deduction or credit, as the case may be, as is earned, realized or available by or to the Company for federal income tax purposes.

7.11 Interpretation. It is the intent of the Members that the provisions hereof relating to each Member's distributive share of income, gain, loss, deduction and credit (and items thereof) shall comply with the provisions of Sections 704(b), 704(c), 706 and other relevant provisions of the Code and the applicable Regulations. In furtherance of the foregoing, the

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Board of Managers is hereby directed to resolve any ambiguity in the provisions of this Agreement in a manner that will preserve and protect the allocations provided for in this Article 7 for federal income tax purposes and, subject to the last sentence hereof, to adopt such curative provisions to this Article 7 as the Board of Managers may deem necessary or appropriate. In the event of any dispute, the decision of the independent tax counsel employed by the Company shall be final. Notwithstanding the foregoing, no Member shall have the right to require or compel any distribution of cash or property not authorized or provided for by the provisions of this Agreement and the Board of Managers shall not have the right to alter any distribution of cash or property provided for by the provisions of this Agreement on the ground that such action is necessary to cause the provisions hereof to conform to the provisions of the Regulations.

ARTICLE 8
TAX MATTERS MEMBER

8.1 Tax Matters Member. Unless and until another Member is designated as the tax matters member by the Board of Managers, Penn Octane Corporation shall be the tax matters member of the Company as provided in the Regulations under Code Section 6231 and any analogous provisions of state law and in such capacity is referred to as the "Tax Matters Member".

8.2 Certain Authorizations. The Tax Matters Member shall represent the Company, at the Company's expense, in connection with all examinations of the Company's affairs by tax authorities including any resulting administrative or judicial proceedings.

8.3 Indemnity of Tax Matters Member. The Company shall indemnify and reimburse the Tax Matters Member for all expenses (including legal and accounting fees) incurred as Tax Matters Member pursuant to this Article 8 in connection with any administrative or judicial proceeding with respect to the tax liability of the Members as long as the Tax Matters Member has determined in good faith that its course of conduct was in, or not opposed to, the best interest of the Company. The payment of all such expenses shall be made before any Distributions are made to the Members. The taking of any action and the incurring of any expense by the Tax Matters Member in connection with any such proceeding, except to the extent provided herein or required by law, is a matter in the sole discretion of the Tax Matters Member and the provisions on limitations of liability of the Tax Matters Member, and indemnification set forth in Article 12 shall be fully applicable to the Tax Matters Member in its capacity as such.

8.4 Notices to Tax Matters Member. Any Member that receives a notice of an administrative proceeding under Code Section 6233 relating to the Company shall promptly notify the Tax Matters Member of the treatment of any Company item on such Member's federal income tax return that is or may be inconsistent with the treatment of that item on the Company's return. Any Member that enters into a settlement agreement with the Secretary with respect to any Company item shall notify the Tax Matters Member of such agreement and its terms within 60 days after its date.

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ARTICLE 9
TRANSFER OF UNITS

9.1 Transfer by Members.

9.1.1 Except as permitted by Section 9.3, no Member shall Transfer all or any part of the economic or other rights that comprise its Units and no Assignee shall Transfer any portion of its Economic Interest unless such Transfer is first approved by the Board of Managers, which approval may be given or refused in the sole and absolute discretion of the Board of Managers.

9.1.2 Notwithstanding Section 9.1.1, but subject to the provisions of Sections 9.1.4, 9.1.5 and 9.3, a Member who is an individual shall be entitled to Transfer all or any portion of its Units to a trust for the benefit of such Member or a Member of the immediate family of such Member (herein referred to as a "Permitted Transferee") so long as the Person controlling such trust is satisfactory to the Board of Managers, provided that the Permitted Transferee in question shall not be admitted as a Member of the Company, but shall remain an Assignee with respect to the interest transferred unless admitted as a Member pursuant to Article 10.

9.1.3 Any holder of Units may pledge such Units to any bank or other financial institution to secure any debt of the Company to such bank or financial institution for borrowed money; provided, however, that no such pledge may be made unless such pledge is first approved by the Board of Managers, which approval may be given or refused in the sole and absolute discretion of the Board of Managers.

9.1.4 No Transfer (including a Transfer to a Permitted Transferee) of all or any part of a Member's Units or an Assignee's Economic Interest may be made pursuant to Section 9.1 or Section 9.3 hereof unless and until the Board of Managers shall have received all of the following (to the extent applicable to the proposed Transfer):

(a) if requested by the Board of Managers, an opinion of responsible counsel (who may be counsel for the Company), satisfactory in form and substance to the Board of Managers to the effect that:

(i) such Transfer would not violate the Securities Act or any state securities or blue sky laws applicable to the Company or the Units to be transferred;

(ii) such Transfer would not cause the Company to be considered a publicly traded partnership under Section 7704(b) of the Code;

(iii) such Transfer would not cause the Company to lose its status as a partnership for federal income tax purposes;

(iv) such Transfer would not require the Company or the Board of Managers to register as an investment adviser under the Investment Advisers Act of 1940, as amended, or to register as an investment

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company under the Investment Company Act of 1940, as amended; and

(v) such Transfer would not cause a termination of the Company for federal income tax purposes; and

(b) the agreement in writing of such Assignee to comply with all of the terms and provisions of this Agreement and the grant of the power of attorney set forth in Section 15.4.

9.1.5 Each Member hereby severally agrees that:

(a) it will not transfer all or any part of its Units in the Company except as permitted by this Agreement;

(b) in no event shall all or any part of a Unit be transferred to a minor or an incompetent except in trust or pursuant to the Uniform Gifts to Minors Act; and

(c) it will pay all reasonable expenses, including attorneys' fees, incurred by the Company in connection with such Transfer.

9.1.6 A transferee of Units or an Economic Interest shall not be admitted as a Member of the Company, but shall remain an Assignee with respect to the Units or Economic Interest transferred unless and until admitted as a Member pursuant to Article 10. Unless a transferee is admitted as a Member of the Company pursuant to Article 10, the Transfer of all of a Member's interest in the profits, losses and capital of the Company shall not cause such Member to cease to be a Member of the Company.

9.1.7 Any Transfer in contravention of any of the provisions of this Article 9 shall be void and of no effect, and shall not bind nor be recognized by the Company.

9.1.8 In the event of a Transfer or the admission of any Assignee as a Member of the Company, the Board of Managers shall promptly prepare a revised Schedule I, which shall be deemed to replace the old Schedule I and constitute an amendment of this Agreement approved by all of the Members, to reflect such Transfer or admission, as the case may be, and shall promptly send a copy of such revised Schedule I to all Members.

9.2 Assignees. If the provisions of this Article 9 have been complied with, an Assignee shall be entitled to receive all distributions of cash or other property from the Company, and to be allocated Net Profit and Net Loss and items of taxable income, deduction, gain, loss or credit attributable to the Economic Interest assigned to the Assignee from and after the effective date of the Transfer; shall succeed to the portion of the Capital Account of the transferor as of the effective date of the Transfer attributable to the Economic Interest which was transferred; and shall have the right to receive a copy of the financial statements and tax information required herein to be provided to all Members. An Assignee shall have no rights of a Member, including without limitation the right to vote as a Member on matters set forth herein or in the Act, which rights of a Member shall continue to be held by the Member from whom the

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Economic Interest derives, unless and until such Assignee is admitted as a Member pursuant to the provisions of Article 10. The Economic Interest of an Assignee shall be subject to all of the restrictions and limitations to which the Units from which the Economic Interest was transferred and to which the Member holding such Units are subject. The Company and Board of Managers shall be entitled to treat the transferor of the Economic Interest transferred to the Assignee as the absolute owner in all respects, and shall incur no liability for Distributions, allocations of Net Profit or Net Loss, or transmittal of reports and notices required to be given to the Assignee that are made in good faith to the transferor Member until the effective date of the Transfer. Unless otherwise agreed by the Board of Managers, the effective date of the Transfer shall be the first day of the calendar month following the month in which the Board of Managers has received all documents with respect to such Transfer required by Section 9.1.4 and an executed instrument of assignment in compliance with this Article 9 or the first day of a later month if specified in the executed instrument of assignment.

9.3 Penn Octane Units. Penn Octane Corporation shall have the right to sell 25,000 of its Units to each of Shore Capital LLC (or its designee) and Jerome B. Richter (or his designee) pursuant to purchase rights granted to by Penn Octane Corporation to such Persons.

ARTICLE 10
ADMISSION OF ASSIGNEE AS MEMBER

10.1 Requirements. An Assignee shall not be admitted to the Company as a Member unless all of the following conditions are first satisfied:

(a) a duly executed and acknowledged written instrument of Transfer is filed with the Company, specifying the Units being transferred and setting forth the intention of the Member effecting the Transfer that the Assignee succeed to a portion or all of such Member's Units as a Member;

(b) the Assignee qualifies as an Accredited Investor;

(c) if requested by the Board of Managers, the Assignee delivers to the Company an opinion of counsel, in form and substance satisfactory to the Board of Managers, to the effect provided in clause (a) of Section 9.1.4 with respect to the admission of the

Assignee as a Member;

(d) the Member effecting the Transfer and Assignee execute and acknowledge any other instruments that the Board of Managers deems necessary or desirable for admission of the Assignee, including the written acceptance and adoption by the Assignee of the provisions of this Agreement and execution, acknowledgment and delivery to the Board of Managers of a special power of attorney as provided in Section 15.4;

(e) the Member effecting the Transfer or the Assignee pays to the Company a transfer fee sufficient to cover all reasonable expenses connected with the admission;

(f) Article 9 of this Agreement has been or is complied with; and

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(g) the Board of Managers approves such admission, which approval may be given or refused in its reasonable discretion.

10.2 Resignation of Member; No Dissolution. If a Member Transfers all of its interest in the profits, losses and capital of the Company pursuant to
Section 9.1 and the transferee of such interest is admitted as a Member pursuant to Section 10.1, such Person shall be admitted to the Company as a Member effective on the effective date of the Transfer or such other date as may be specified when the Member is admitted, and immediately following such admission, the transferor Member shall cease to be a Member of the Company.

ARTICLE 11
DISSOLUTION OF COMPANY

11.1 Termination of Company. No Member shall resign or withdraw from the Company except that, subject to the restrictions set forth in Articles 9 and 10 hereof, any Member may Transfer its Units in the Company to an Assignee and an Assignee may become a Member in place of the Member which assigned its Units. If any Member ceases to be a Member for any reason, the business of the Company shall be continued by the remaining Members.

11.2 Events of Dissolution or Liquidation. The Company shall be dissolved upon the happening of any of the following events: (a) the written determination of the Board of Managers or (b) the Sale of the Company.

11.3 Liquidation. Upon dissolution of the Company for any reason, the Company shall immediately commence to wind up its affairs. A reasonable period of time shall be allowed for the orderly termination of the Company's business, discharge of its liabilities, and distribution or liquidation of the remaining assets so as to enable the Company to minimize the normal losses attendant to the liquidation process. The Company's property and assets or the proceeds from the liquidation thereof shall be distributed so as not to contravene the Act but in compliance with Section 7.2; provided, however, that Distributions to Members shall be made after their Capital Accounts have been adjusted to reflect all Net Profits and Net Losses of the Company through the date of distribution.

11.4 No Action for Dissolution. The Members acknowledge that irreparable damage would be done to the goodwill and reputation of the Company if any Member should bring an action in court to dissolve the Company under circumstances where dissolution is not required by Section 11.2. This Agreement has been drawn carefully to provide fair treatment of all parties and equitable payment in liquidation of the Units of all Members. Accordingly, except where the Board of Managers has failed to liquidate the Company as required by Section 11.2 and except as specifically provided in the Act, each Member hereby waives and renounces its right to initiate legal action to seek dissolution or to seek the appointment of a receiver or trustee to liquidate the Company.

11.5 No Further Claim. Upon dissolution, each Member shall look solely to the assets of the Company for the return of its capital, and if the Company's property remaining after payment or discharge of the debts and liabilities of the Company, including debts and liabilities

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owed to one or more of the Members, is insufficient to return the aggregate Capital Contributions of each Member, such Members shall have no recourse against the Company, the Board of Managers or any other Member.

ARTICLE 12
INDEMNIFICATION

12.1 General. The Company shall indemnify, defend and hold harmless the Board of Managers and each member of the Board of Managers, each Member, including the Tax Matters Member, each Assignee and each such Persons officers, directors, shareholders, members, partners, employees and agents; and the employees, officers and agents of the Company (all indemnified persons being referred to as "Indemnified Persons") from any liability, loss or damage incurred by the Indemnified Person by reason of any act performed or omitted to be performed by the Indemnified Person in connection with the business of the Company and from liabilities or obligations of the Company imposed on such Person by virtue of such Person's position with the Company, including reasonable attorneys' fees and costs and any amounts expended in the settlement of any such claims of liability, loss or damage; provided, however, that if the liability, loss, damage or claim arises out of any action or inaction of an Indemnified Person, indemnification under this Section 12.1 shall be available only if (a) either (i) the Indemnified Person, at the time of such action or inaction, determined in good faith that its, his or her course of conduct was in, or not opposed to, the best interests of the Company, or (ii) in the case of inaction by the Indemnified Person, the Indemnified Person did not intend its, his or her inaction to be harmful or opposed to the best interests of the Company, and (b) the action or inaction did not constitute fraud, gross negligence or willful misconduct by the Indemnified Person or a breach of this Agreement; and provided, further, that indemnification under this Section 12.1 shall be recoverable only from the assets of the Company and not from any assets of the Members. THE FOREGOING INDEMNITY IS INTENDED TO INDEMNIFY EACH INDEMNIFIED PERSON FOR HIS OWN ACTS OF NEGLIGENCE AND SHALL APPLY IRRESPECTIVE OF ANY CLAIM OF CONCURRENT OR CONTRIBUTORY NEGLIGENCE ON THE PART OF SUCH INDEMNIFIED PERSON. The Company may pay or reimburse attorneys' fees of an Indemnified Person as incurred, if such Indemnified Person executes an undertaking to repay the amount so paid or reimbursed if there is a final determination by a court of competent jurisdiction that such Indemnified Person is not entitled to indemnification under this Article 12. The Company may pay for insurance covering liability of the Indemnified Persons for negligence in operation of the Company's affairs.

12.2 Persons Entitled to Indemnity. Any Person who is within the definition of "Indemnified Person" at the time of any action or inaction in connection with the business of the Company shall be entitled to the benefits of this Article 12 as an Indemnified Person with respect thereto, regardless if such Person continues to be within the definition of "Indemnified Person" at the time of such Indemnified Person's claim for indemnification or exculpation hereunder.

12.3 Procedure Agreements. The Company may enter into an agreement with any of its officers, employees and agents, or the members of the Board of Managers, setting forth procedures consistent with applicable law for implementing the indemnities provided in this Article 12.

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12.4 Fiduciary and Other Duties. An Indemnified Person acting under this Agreement shall not be liable to the Company or to any other Indemnified Person for its good faith reliance on the provisions of this Agreement. The provisions of this Agreement, to the extent that they restrict the duties (including fiduciary duties) and liabilities of an Indemnified Person otherwise existing at law or in equity, are agreed by the parties hereto to replace such other duties and liabilities of such Indemnified Person.

12.5 Exculpation. No Indemnified Person shall be liable, in damages or otherwise, to the Company or to any Member for any loss that arises out of any act performed or omitted to be performed by it or him pursuant to the authority granted by this Agreement if (a) either (i) the Indemnified Person, at the time of such action or inaction, determined, in good faith, that such Indemnified Person's course of conduct was in, or not opposed to, the best interests of the Company, or (ii) in the case of inaction by the Indemnified Person, the Indemnified Person did not intend such Indemnified Person's inaction to be harmful or opposed to the best interests of the Company, and (b) the conduct of the Indemnified Person did not constitute fraud, gross negligence, or willful misconduct by such Indemnified Person or a breach of this Agreement.

12.6 Except as otherwise provided by the Act, the debts, obligations and liabilities of the Company, whether arising in contract, tort or otherwise, shall be solely the debts, obligations and liabilities of the Company, and no Indemnified Person shall be obligated personally for any such debt, obligation or liability of the Company solely by reason of being an Indemnified Person. All persons dealing with the Company shall look solely to the assets of the Company for the payment of the debts, obligations or liabilities of the Company.

ARTICLE 13
REPRESENTATIONS AND COVENANTS BY THE MEMBERS

Each Member hereby represents and warrants to, and agrees with, the Board of Managers, the other Members and the Company as follows:

13.1 Investment Intent. It is acquiring its Units with the intent of holding the same for investment for its own account and without the intent or a view of participating directly or indirectly in any distribution of such Units within the meaning of the Securities Act or any applicable state securities laws.

13.2 Securities Regulation.

13.2.1 It acknowledges and agrees that its Units are being issued and sold in reliance on the exemption from registration contained in Section 4(2) of the Securities Act and exemptions contained in applicable state securities laws, and that its Units cannot and will not be sold or transferred except in a transaction that is exempt under the Securities Act and those state acts or pursuant to an effective registration statement under the Securities Act and those state acts or in a transaction that is otherwise in compliance with the Securities Act and those state acts.

13.2.2 It understands that it has no contractual right for the registration under the Securities Act of its Units for public sale and that, unless its Units are registered or an exemption from registration is available, its Units may be required to be held indefinitely.

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13.3 Knowledge and Experience. It has such knowledge and experience in financial, tax and business matters as to enable it to evaluate the merits and risks of its investment in the Company and to make an informed investment decision with respect thereto.

13.4 Economic Risk. It is able to bear the economic risk of its investment in its Units.

13.5 Binding Agreement. It has all requisite power and authority to enter into and perform this Agreement and that this Agreement is and will remain its valid and binding agreement, enforceable in accordance with its terms (subject, as to the enforcement of remedies, to any applicable bankruptcy, insolvency or other laws affecting the enforcement of creditors rights).

13.6 Tax Position. Unless it provides prior written notice to the Company, it will not take a position on its federal income tax return, in any claim for refund, or in any administrative or legal proceedings that is inconsistent with any information return filed by the Company or with the provisions of this Agreement.

13.7 Information. It has received all documents, books and records pertaining to an investment in the Company requested by it. It has had a reasonable opportunity to ask questions of and receive answers concerning the Company, and all such questions have been answered to its satisfaction.

13.8 Amendments to Agreement. This Agreement may be modified or amended with the prior written consent of the Board of Managers; provided; however, that this Agreement may not be amended (a) without the approval of each Member or Assignee materially adversely affected if the amendment would reduce any such Person's number of Units or would reduce the allocation to such Person of the amount of any Net Profit, Net Loss or distribution of cash or property from that which is provided or contemplated herein, unless (i) such amendment is being executed to reflect any dilution in such Person's interest resulting from the issuance of Units as contemplated by Article 3 or to reflect the preference over any such Units of any new Units issued under Article 3, (ii) such amendment is being executed to reflect the acceptance of an Assignee as a new Member pursuant to Article 10 or (iii) such amendment adversely affects all Members (and their Assignees) equally. Notwithstanding the foregoing sentence, Amendments to this Agreement that (a) are necessary or desirable to cure any ambiguity, to correct or supplement any provision herein that would be inconsistent with law or with any other provision herein, or to make any other provision with respect to matters or questions arising under this Agreement that will not be inconsistent with law or with the provisions of this Agreement; (b) are necessary or desirable to satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or contained in any federal or state statute; or (c) contemplated by this Agreement in Section 2.2 in respect of the name of the Company, Section 2.3 in respect of the registered office and registered agent of the Company, Section 2.7 in respect to persons authorized to act on behalf of the Company and

Schedule I of this Agreement, may be made by the Board of Managers without the consent of any Members, and such amendments and revised Schedule I shall be deemed to constitute an amendment of this Agreement approved by all of the Members.

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All amendments to this Agreement will be sent to each Member and, after the effective date of the Transfer to such Assignee, to each Assignee promptly after the effectiveness thereof. Any modification or amendment to this Agreement pursuant to this Article 13 shall be binding on all Members.

ARTICLE 14
RIGHT TO CONVERT FORM OF COMPANY

14.1 Election. With the prior written consent of the Supermajority Vote of the Board of Managers, but without any need for consent or approval of any other Member, the Board of Managers may elect at any time and for any purpose to require that the Company be converted into a corporation (in connection with an initial public offering or otherwise), which conversion shall be effected by merger or by such other form of transaction as may be available under applicable law. No Member shall have any voting rights with respect to the election to convert the Company into a corporation or partnership. In such conversion, the Units of the Members (determined as though such Units included Distributions to which the Members would then be entitled under Section 11.3 if the Company were liquidated at the value of the Company determined in connection with such conversion) as well as any unvested Units shall be the basis for the allocation of shares or options in the corporation. Upon such an election, the Members shall as soon as practicable thereafter execute, acknowledge and deliver, or cause to be executed, acknowledged and delivered, all instruments and documents that may be reasonably requested by the Board of Managers to best effectuate the conversion of the Company to a corporation while continuing in full force and effect, to the extent consistent with such conversion, the terms, provisions and conditions of this Agreement, including those provisions granting the Board of Managers exclusive authority to manage the operations and affairs of the Company subject to the provisions hereof, restricting the Transfer of Units, and granting rights to repurchase Units or rights to participate in certain transactions.

ARTICLE 15
MISCELLANEOUS

15.1 Additional Documents. At any time and from time to time after the date of this Agreement, upon the request of the Board of Managers, each Member shall do and perform, or cause to be done and performed, all such additional acts and deeds, and shall execute, acknowledge and deliver, or cause to be executed, acknowledged and delivered, all such additional instruments and documents as may be required to effectuate the purposes and intent of this Agreement.

15.2 General. This Agreement: (a) shall be binding upon the executors, administrators, estates, heirs and legal successors of the Members; (b) shall be governed by and construed in accordance with the laws of the State of Delaware, without regard to principles of conflict of laws; (c) may be executed in more than one counterpart as of the day and year first above written; and (d) contains the entire contract among the Members as to the subject matter hereof. The waiver of any of the provisions, terms or conditions contained in this Agreement shall not be considered as a waiver of any of the other provisions, terms or conditions hereof.

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15.3 Notices, etc. All notices and other communications required or permitted hereunder shall be in writing and shall be deemed effectively given upon personal delivery or receipt (which may be evidenced by a return receipt if sent by registered mail or by signature if delivered by courier or delivery service) addressed (a) if to any Member, at the address of such Member set forth in the records of the Company or at such other address as such Member shall have furnished to the Company in writing as the address to which notices are to be sent hereunder, and (b) if to the Company or to the Board of Managers, to it.

15.4 Execution of Papers. The Members agree to execute such instruments, documents and papers as the Board of Managers deems necessary or appropriate to carry out the intent of this Agreement. Each Member, including each new and substituted Member, by the execution of this Agreement or by agreeing in writing to be bound by the provisions of this Agreement, irrevocably constitutes and appoints each member of the Board of Managers and/or any Person designated by the Board of Managers to act on its behalf for purposes of this Section 15.4 its true and lawful attorney-in-fact with full power and authority in its name, place and stead to execute, acknowledge, deliver, swear to, file and record at the appropriate public offices such documents as may be necessary or appropriate to carry out the provisions of this Agreement, including but not limited to:

(a) all certificates and other instruments (specifically including counterparts of this Agreement), and any amendment thereof, that the Board of Managers deems appropriate to qualify or continue the Company as a limited liability company in any jurisdiction in which the Company may conduct business or in which such qualification or continuation is, in the opinion of the Board of Managers, necessary to protect the limited liability of the Members;

(b) all amendments to this Agreement adopted in accordance with the terms hereof and all instruments that the Board of Managers deems appropriate to reflect a change or modification of the Company in accordance with the terms of this Agreement; and

(c) all conveyances and other instruments that the Board of Managers deems appropriate to reflect the dissolution of the Company.

The appointment by each Member of each member of the Board of Managers and/or any Person designated by the Board of Managers as its attorney-in-fact shall be deemed to be a power coupled with an interest, in recognition of the fact that each of the Members under this Agreement will be relying upon the power of the Board of Managers to act as contemplated by this Agreement in any filing and other action by it on behalf of the Company, and shall survive and shall not be affected by the subsequent disability, incapacity, the bankruptcy, dissolution, death, adjudication of incompetence or insanity of any Member giving such power and the transfer or assignment of all or any part of such Member's Units; provided, however, that in the event of a Transfer by a Member of all of its Units, the power of attorney given by the transferor shall survive such assignment only until such time as the Assignee shall have been admitted to the Company as a substituted Member and all required documents and instruments shall have been duly executed, filed and recorded to effect such substitution.

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15.5 Disputed Matters. Except as otherwise provided in this Agreement, any controversy or dispute arising out of this Agreement, the interpretation of any of the provisions hereof, or the action or inaction of any Member hereunder shall be submitted to arbitration in Houston, Texas, pursuant to the provisions set forth in Exhibit 15.5 hereto. To the fullest extent permitted by law, no action at law or in equity based upon any claim arising out of or related to this Agreement shall be instituted in any court by any Member except (a) an action to compel arbitration pursuant to this Section 15.5, or (b) an action to enforce an award obtained in an arbitration proceeding in accordance with this
Section 15.5.

15.6 Gender and Number. Whenever required by the context, as used in this Agreement the singular number shall include the plural, the plural shall include the singular, and all words herein in any gender shall be deemed to include the masculine, feminine and neuter genders.

15.7 Severability. If any provision of this Agreement is determined by a court to be invalid or unenforceable, that determination shall not affect the other provisions hereof, each of which shall be construed and enforced as if the invalid or unenforceable portion were not contained herein. That invalidity or unenforceability shall not affect any valid and enforceable application thereof, and each said provision shall be deemed to be effective, operative, made, entered into or taken in the manner and to the full extent permitted by law.

15.8 Headings. The headings used in this Agreement are used for administrative convenience only and do not constitute substantive matter to be considered in construing the terms of this Agreement.

15.9 No Third Party Rights. The provisions of this Agreement are for the benefit of the Company, the Board of Managers, the Members and Assignees and no other Person, including creditors of the Company, shall have any right or claim against the Company, the Board of Managers or any Member by reason of this Agreement or any provision hereof or be entitled to enforce any provision of this Agreement.

[Remainder of page intentionally left blank.]

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IN WITNESS WHEREOF, the parties have executed this Limited Liability Company Agreement as of the day and year first set forth above.

MEMBERS:

PENN OCTANE CORPORATION

By:  /s/  Ian T. Bothwell
     ----------------------------
          Ian T. Bothwell
          Chief Financial Officer

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                                   SCHEDULE I
                                   ----------


Members:                 Capital Contributions    Units   Per Unit Value
-----------------------  ----------------------  -------  --------------
Penn Octane Corporation  $1,000                  100,000  $.01

Schedule I-1


EXHIBIT 1

DEFINED TERMS

"Accredited Investor" has the meaning assigned to such term under Regulation D promulgated pursuant to Section 4(2) of the Securities Act.

"Act" shall mean the Delaware Limited Liability Company Act as amended and

in effect from time to time.

"Adjusted Capital Account Deficit" means, with respect to any Member, the deficit balance, if any, in such Member's Capital Account as of the end of the relevant Fiscal Year after giving effect to the following adjustments:

(i) credit to such Capital Account any amounts which such Member is obligated to restore pursuant to any provision of this Agreement or is deemed to be obligated to restore pursuant to the next to the last sentences of Regulation Sections 1.704-2(g)(1) and 1.704-2(i)(5) after taking into account any changes during such year in Company minimum gain and Member minimum gain (as determined under such Regulations); and

(ii) debit to such Capital Account the items described in Section 1.704-1
(b)(2)(1)(d)(4), (5) and (6) of the Regulations.

"Adjusted Taxable Income" shall mean the Company's cumulative items of income or gain less cumulative items of loss or deduction under the Code, computed from the Effective Date through the date such Adjusted Taxable Income is being computed, except that gain or loss from a Sale of the Company.

"Affiliate" shall mean, with respect to any specified Person, any Person that directly or through one or more intermediaries controls or is controlled by or is under common control with the specified Person. As used in this definition, the term "control" means the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of a Person, whether through ownership of voting securities, by contract or otherwise.

"Agreement" shall mean this Amended and Restated Limited Liability Company Agreement of the Company dated as of the Effective Date, as amended from time to time.

"Assignee" shall mean a Person that has acquired the right from a Member to
(i) share in Net Profit and Net Loss of the Company, (ii) receive Distributions and (iii) receive the allocation of taxable income, gain, loss, deductions or credits (and items thereof) of the Company to which the transferor Member was entitled in accordance with the provisions of Article 9, but has not been admitted as a Member of the Company in accordance with the provisions of Article 10.

"Board of Managers" shall mean the board of managers elected and determined as provided in Section 5.1.

"Book Gain" or "Book Loss" shall mean the gain or loss recognized by the Company for Code Section 704(b) book purposes in any Fiscal Year or other period by reason of the sale,

Exhibit 1-1


exchange or other disposition of any Company asset. Such Book Gain or Book Loss shall be computed by reference to the Book Value of such asset as of the date of such sale, exchange or other disposition, rather than by reference to the tax basis of such asset as of such date, and each and every reference herein to "gain" or "loss" shall be deemed to refer to Book Gain or Book Loss, rather than to tax gain or tax loss, unless otherwise expressly provided herein.

"Book Value" of an asset shall mean, as of any particular date, the value at which the asset is properly reflected on the books and records of the Company as of such date. The initial Book Value of each asset shall be its cost, unless such asset was contributed to the Company by a Member, in which case the initial Book Value shall be the Fair Market Value of such asset at the time of contribution, as agreed to by the Members or determined by the Board of Managers, and such Book Value shall thereafter be adjusted for Depreciation with respect to such asset rather than for the cost recovery deductions to which the Company is entitled for federal income tax purposes with respect thereto.

"Capital Account" is defined in Section 3.2. An Assignee may acquire an interest in a Capital Account as provided in Section 9.2.

"Capital Contribution" shall mean with respect to any Member, the amount of money plus the Fair Market Value of any other property (net of liabilities assumed or to which the property is subject) contributed to the Company with respect to the Units held by such Member pursuant to the terms of this Agreement.

"Certificate" shall mean the Certificate of Formation of the Company and any and all amendments thereto and restatements thereof filed on behalf of the Company with the office of the Secretary of State of the State of Delaware pursuant to the Act.

"Code" shall mean the Internal Revenue Code of 1986, as amended from time

to time, and the corresponding provisions of any future federal tax law.

"Combined Effective Marginal Tax Rate" shall mean the highest single combined rate (expressed as a percentage) of United States federal, state and local income taxation applicable to any individual residing in California determined as of the last day of each Tax Estimation Period, without giving effect to any limitation on the deductibility of state and local taxes and other itemized deductions in computing United States federal taxable income and assuming that such individual is subject to the highest United States federal and highest state and local marginal ordinary income tax rates on all income allocated by the Company.

"Company" shall mean the Limited Liability Company formed by virtue of this Agreement and the filing of the Certificate in accordance with the Act.

"Depreciation" shall mean for each Fiscal Year or other period, an amount equal to the depreciation, amortization or other cost recovery deduction allowable with respect to an asset for such year or other period for federal income tax purposes, except if the Book Value of an asset differs from its adjusted basis for federal income tax purposes at the beginning of any such year or other period, Depreciation shall be an amount that bears the same relationship to the Book Value of such asset as the depreciation, amortization, or other cost recovery deduction computed

Exhibit 1-2


for tax purposes with respect to such asset for the applicable period bears to the adjusted tax basis of such asset at the beginning of such period, or if such asset has a zero adjusted tax basis, Depreciation shall be an amount determined under any reasonable method selected by the Board of Managers, with the advice of its independent accountants.

"Distribution" shall mean cash or property (net of liabilities assumed or to which the property is subject) distributed to a Member or an Assignee in respect of the Member's Units in the Company.

"Economic Interest" shall mean all of the rights of an Assignee with respect to an Interest.

"Effective Date" shall mean September 16, 2004.

"Equity Kickers" is defined in Section 3.7.1.

"Fair Market Value" means, as of any date, the Board of Managers' good faith determination of the fair value of one Unit of the applicable class as of the applicable reference date.

"Fiscal Year" shall mean the fiscal year of the Company, which shall be the calendar year, or such other fiscal year as determined by the Board of Managers.

"Indemnified Persons" is defined in Section 12.1.

"Interest" shall mean the entire interest of a Member in the capital, profits and Distributions of the Company, including any and all rights and benefits to which a Member may be entitled as provided in this Agreement, together with the obligations of such Member to comply with all the terms and provisions of this Agreement.

"Majority Interest" shall mean the vote or consent of the Members holding a majority of the Units.

"Management Members" shall mean such employees, managers, independent contractors or consultants of the Company, a Member or its Affiliates, who are granted Units of the Company in connection with such employment or services rendered or to be rendered or who acquired such Units pursuant to the exercise of an option granted in connection with such employment or services rendered or to be rendered or as an investment in the Company.

"Member Nonrecourse Deductions" shall have the meaning set forth in Regulation Section 1.704-2(i)(1).

"Members" shall mean the Persons listed as Members on Schedule I to this Agreement and any other Person that both acquires an Interest in the Company and is admitted to the Company as a Member of the Company.

"Net Profit" and "Net Loss" shall mean, for each Fiscal Year or other period, an amount equal to the Company's taxable income or loss, respectively, for such year or period, determined

Exhibit 1-3


in accordance with Section 703(a) of the Code (taking into account all items of income, gain, loss or deduction required to be stated separately pursuant to
Section 703(a)(1) of the Code), with the following adjustments:

(i) any income of the Company that is exempt from federal income tax and not otherwise taken into account in computing Net Profit or Net Loss pursuant to this provision shall be added to such taxable income or loss;

(ii) any expenditures of the Company described in Section 705(a)(2)(B) of the Code (relating to expenditures which are neither deductible nor properly chargeable to capital) or treated as Code Section 705(a)(2)(B) expenditures pursuant to Section 1.704-1(b)(2)(iv)(i) of the Regulations, and not otherwise taken into account in computing Net Profit or Net Loss pursuant to this provision, shall be subtracted from such taxable income or loss;

(iii) Book Gain or Book Loss from the sale or other disposition of any asset of the Company shall be taken into account in lieu of any tax gain or tax loss recognized by the Company by reason of such sale or other disposition; and

(iv) in lieu of the depreciation, amortization and other cost recovery deductions taken into account in computing such taxable income or loss, there shall be taken into account Depreciation for such fiscal year or other period, computed as provided in this Agreement.

"New Securities" is defined in Section 3.7.1.

"Nonrecourse Deductions" shall have the meaning set forth in Regulation Section 1.7042(b)(1).

"Permitted Transferee" is defined in Section 9.1.2.

"Person" shall mean an individual, partnership, joint venture, association, corporation, trust, estate, limited partnership, limited liability company, limited liability partnership, or any other legal entity.

"Qualified Income Offset" shall have the meaning set forth in Regulation Section 1.704-1(b)(2)(ii)(d).

"Regulations" shall mean the Treasury regulations, including temporary regulations, promulgated under the Code, as such regulations may be amended from time to time (including the corresponding provisions of any future regulations) as such regulations are applicable to the Company or transactions of the Company.

"Sale of the Company" shall mean, in each case as determined in good faith by the Board of Managers, to have been occasioned by, or to have occurred upon, the acquisition of the Company by another Person by means of any transaction or series of related transactions (including, without limitation, any merger, consolidation, sale, assignment, transfer distribution

Exhibit 1-4


or issuance of Units) that results in the Members immediately prior to such transaction not holding, directly or indirectly, at least 50% of the voting power of the surviving or continuing entity.

"Securities Act" shall mean the Securities Act of 1933, as amended.

"Sole Discretion" means, with respect to any Person, that Person's sole and absolute discretion, with or without cause, and subject to such conditions as he shall deem appropriate.

"Supermajority Vote" shall mean the vote or consent of a majority of the Managers of the Board of Managers.

"Tax Distribution" is defined in Section 7.2.1.

"Tax Estimation Period" shall mean (i) January, February and March (ii) April and May, (iii) June, July and August, and (iv) September, October, November and December of each year during the term of the Company, or other periods for which estimates of individual federal income tax liability are required to be made under the Code, provided that the Company's first Tax Estimation Period shall begin on the Effective Date of this Agreement.

"Tax Matters Member" is defined in Section 8.1.

"Transfer" shall mean a sale, assignment, pledge, encumbrance, abandonment, disposition, contribution, distribution, exchange or other transfer, including but not limited to, any distribution to partners of any partnership, shareholders of any corporation or members of any limited liability company, and may be used either as a verb or a noun.

"Units" shall mean any of the Units of the Company.

Exhibit 1-5


EXHIBIT 5.1

BOARD OF MANAGERS

The Members hereby appoint the following individuals as the members of the Board of Managers:

RICHARD SHORE, JR.

JEROME B. RICHTER

MURRAY J. FEIWELL

RICARDO RODRIGUEZ CANNEY

DOUGLAS MANNER

Exhibit 5.1-1


EXHIBIT 15.5

ARBITRATION POLICY

1. Disputes Covered. This Arbitration Policy ("Policy") applies to any claim, dispute or controversy arising out of or relating to the terms and conditions of any incentive plan, partnership agreement or other plan, document or agreement that expressly refers to and incorporates the terms of this Policy; any such claim, dispute or controversy so covered by the terms of this Policy shall, except as otherwise expressly provided, be settled by binding arbitration in accordance with the procedures and conditions set forth herein.

The scope of this Policy is intended to be applied broadly so as to include any and all disputes, controversies and claims that touch upon any incentive plan, partnership agreement or other plan, document or agreement covered by this Policy, whether such disputes, controversies or claims involve a breach of contract, contract interpretation, tort law, common law principles or statutes, rules or regulations.

Any dispute, controversy or claim to which this Policy applies is hereinafter called a "Dispute." A person, corporation or entity who is subject to this agreement is hereinafter called a "Party."

2. Mediation. The Parties to a Dispute agree to try in good faith to settle the Dispute by mediation administered by the American Arbitration Association ("AAA") under its Commercial Mediation Rules before resorting

to binding arbitration. The Parties shall split the cost of the mediator equally. To qualify as a mediator, the mediator must be a lawyer admitted to the Bar of any State who has practiced for at least ten years. Nothing in this clause shall preclude any Party from initiating arbitration if the mediation does not reach a resolution within 30 days after the mediation commences.

3. Arbitration. Any Dispute not resolved by mediation shall be finally resolved by binding arbitration administered by the AAA pursuant to the Commercial Arbitration Rules of the AAA (the "Rules") as in force at the time the arbitration is commenced, except as modified by this Policy. In the event of any conflict between the Rules and this Policy, the provisions of this Policy will control.

4. Commencement of Arbitration. Subject to prior compliance with paragraph 2 above, any Party may at any time initiate an arbitration hereunder by giving a written notice ("Demand for Arbitration") to the other Party at any time consistent with any applicable statutes of limitation.

5. Number of Arbitrators. If the Dispute involves an amount in controversy less than $500,000, then the arbitration of such Dispute shall be conducted before one neutral arbitrator. If the Dispute involves an amount in controversy of $500,000 or more, the arbitration of such Dispute shall be conducted before a tribunal composed of three neutral arbitrators. Whether one or three arbitrators is required, the arbitral tribunal that is to conduct the arbitration is hereinafter called the "Arbitral Panel."

Exhibit 15.5-1


6. Appointment of Arbitral Panel of One. If an Arbitral Panel of one neutral arbitrator is to conduct the arbitration, the arbitrator shall be chosen from a panel of five proposed arbitrators drawn by the AAA. Each Party shall have the right to exercise unlimited challenges for cause and two peremptory strikes within ten days of its receipt of the list of proposed arbitrators. If one panel member remains after strikes are made, such person shall serve as the arbitrator. If more than one panel member remains after strikes are made, the AAA shall choose the arbitrator from the remaining panel members. If all of the panel members are struck by the Parties pursuant to permitted strikes, the AAA shall draw successive new panels of five proposed arbitrators and apply the foregoing procedures with respect to such panel(s) until the arbitrator is selected.

7. Appointment of Arbitral Panel of Three. If an Arbitral Panel of three neutral arbitrators is to conduct the arbitration, each Party shall choose one neutral arbitrator that is chosen from a panel of five proposed arbitrators drawn by the AAA. Each Party shall give the other Party written notice of its selection of one neutral arbitrator within 20 days after its receipt of the Demand for Arbitration. The two arbitrators so selected shall choose the third arbitrator from a panel of five proposed arbitrators drawn by the AAA. If the two arbitrators do not agree on the selection of the third arbitrator within ten days after their receipt of the list of proposed arbitrators, the third arbitrator shall be selected by the Regional Vice President of the AAA from the panel proposed by the AAA. The third arbitrator shall serve as the Chairperson of the Arbitral Panel. If an Arbitral Panel of three conducts the arbitration, all decisions and rulings, as well as any interim or final awards, shall be pursuant to the majority vote of the Arbitral Panel.

8. Place of Arbitration. The place of arbitration shall be Houston, Texas or such other location as the Parties may mutually agree.

9. Limitations and Laches. The Arbitral Panel is directed to consider any defense that all or part of the claim is not timely by reason of laches or statute of limitations as a preliminary issue and to render a signed, written award determining the merits of such defense before considering the substantive merits of the arbitration claim, unless the Arbitral Panel determines that the merits of such defense of laches or statute of limitations are so intertwined with the substantive merits of the arbitration claim as to make impractical the determination of the defense of laches or limitations as a preliminary matter.

10. Preliminary Issues of Law. The Arbitral Panel shall hear and determine any preliminary issue of law asserted by a Party to be dispositive of any claim, in whole or part, in the manner of a federal court hearing a motion to dismiss for failure to state a claim or for summary judgment, pursuant to such terms and procedures as the Arbitral Panel deems appropriate.

11. Consolidation of Disputes. Any court with jurisdiction may order the consolidation of any arbitrable dispute with any related arbitrable dispute, controversy or claim not covered by this Policy, as the court may deem necessary in the interests of justice or efficiency or on such other grounds as the court may deem appropriate.

Exhibit 5.1-2


12. Time of Proceedings. It is the intent of the Parties that, barring extraordinary circumstances, any arbitration shall be conducted in a reasonably expeditious manner and shall be concluded, in any event, within 150 days of the date the Demand for Arbitration is received by the AAA. Unless the Parties otherwise agree, once commenced, hearings shall be held four days a week, three weeks a month, with each hearing day to begin at 9:30 a.m. and to conclude at 4:45 p.m. until the arbitration is completed. The Parties may upon agreement extend these time limits, or the Arbitral Panel may extend them if they determine that the interests of justice otherwise requires. The Arbitral Panel shall use its best efforts to issue the final award or awards within a period of 20 days after closure of the proceedings. However, failure to do so shall not be a basis for challenging the award.

13. Pre-Hearing Conference. Within ten days after the appointment of the Arbitral Panel, the Arbitral Panel shall hold a pre-hearing conference to discuss discovery matters, to schedule the hearing, to decide procedural matters and to address all other questions that may be presented.

14. Discovery and Evidence. Except as may be modified by the Arbitral Panel for good cause shown, the following procedures shall be followed in addition to those set forth within the Rules themselves. At least 20 days before the arbitration, the Parties must exchange a list of witnesses, including any experts, and copies of all exhibits intended to be used at the arbitration. Except for good cause, the Arbitral Panel may refuse to allow into evidence the testimony of any witness not timely disclosed. In addition, except for good cause, the Arbitral Panel may exclude from evidence any exhibit not previously tendered to the opposing Party in a timely fashion. Each Party may take the deposition of three individuals and any or all expert witnesses designated by another Party. Additional discovery, including but not limited to interrogatories and requests for production of documents, medical or psychological examinations, may be had, upon a showing of substantial need, where the Arbitral Panel so orders.

15. Record of Hearing. If requested by any Party, the Arbitral Panel shall keep records of all proceedings and decisions, and a verbatim record of all oral hearings. The cost of any such transcript will be borne by the requesting party.

16. Cross-examination. It is the intent of the Parties that the testimony of witnesses be subject to cross-examination.

17. Evidence. Strict rules of evidence shall not apply in an arbitration conducted pursuant to this Policy. The Parties may offer such evidence as they desire and the Arbitral Panel shall accept such evidence as the Arbitral Panels deems relevant to the issues and accord it such weight as the Arbitral Panel deems appropriate.

18. Affidavits. The Parties may submit evidence in the form of sworn affidavits, provided that upon the request of another Party, the Party submitting the affidavit will make the affiant available for cross-examination. If the affiant is not made available for cross-examination, the affidavit shall not be considered as evidence by the Arbitral Panel except as to matters relating to authentication of documents or signatures and other such nonmaterial facts except if the Arbitral Panel finds that the affiant is beyond the control

Exhibit 5.1-3


of the Party offering the affidavit, the affiant is unavailable and the interests of justice require consideration of the evidence submitted by the affiant.

19. Punitive Damages Prohibited. The Parties hereby waive any claim to any damages in the nature of punitive, exemplary, or statutory damages in excess of compensatory damages, or any form of damages in excess of compensatory damages, and the Arbitral Panel is specially divested of any power to award any damages in the nature of punitive, exemplary, or statutory damages in excess of compensatory damages, or any form of damages in excess of compensatory damages.

20. Written Opinion. The arbitration award shall be based on and accompanied by a signed, written opinion containing findings of fact and conclusions of law. Any arbitrator dissenting from an award or portion thereof shall issue a dissent stating the reasons for the dissent. The results of the arbitration, unless otherwise agreed by the Parties, are confidential and may not be reported by any news agency or legal publisher or service.

21. Entry of Judgment. A judgment on the arbitration award may be entered in any court having jurisdiction thereof.

22. Costs. The Party prevailing on substantially all of its claims shall be entitled to recover its reasonable costs, including the arbitrators' fees, and its attorneys' fees for the arbitration proceedings, as well as for any ancillary proceeding, including a proceeding to compel or enjoin arbitration, to request interim measures or to confirm or set aside an award.

23. Confidentiality. The Parties and Arbitral Panel shall treat all aspects of the arbitration proceedings, including without limitation the filing of any demand, discovery, testimony and other evidence, briefs and the award, as strictly confidential.

24. Forum Selection. The courts located in the State of Texas shall have exclusive jurisdiction over an action brought to enforce the rights and obligations created or arising under this Policy, and each Party irrevocably submits to the jurisdiction of said courts.

25. Governing Substantive Law. The Arbitral Panel shall apply the substantive law (and the law of remedies, if applicable) of the State of Delaware, or federal law or both, as applicable to the claim(s) asserted. The Arbitral Panel shall recognize all applicable privileges recognized by the law of the State of Delaware, or federal law or both, as applicable to the claim(s) asserted. The Parties expressly prohibit the Arbitral Panel from reaching decisions as amicable compounder/amiables compositeur, specifically, an Arbitral Panel is not authorized to abate the application of law in favor of natural equity. The Arbitral Panel shall have the authority to entertain a motion to dismiss, a motion for summary judgment and/or a motion for judgment as a matter of law and shall apply the standards governing such motions under the Federal Rules of Civil Procedure.

26. Governing Arbitration Law. The law applicable to the validity of the arbitration clause, the conduct of the arbitration, including any resort to a court for provisional remedies, the enforcement of any award and any other question of arbitration law or procedure shall be the Federal Arbitration Act. The Parties agree that this Policy shall be amended if, and to

Exhibit 5.1-4


the extent, necessary to cure any defect affecting enforceability of the duty to arbitrate under the Federal Arbitration Act, it being the intent of the Parties to resolve any dispute by arbitration.

27. Binding Effect. This Policy shall be binding upon the Parties and their respective successors, assigns, heirs, personal representatives and estates.

28. Severability. Should one or more provisions of this Policy be rendered or declared invalid by reason of any existing or subsequently enacted legislation, or by a decree of a court of competent jurisdiction, such invalidation of such provision or provisions hereof shall not affect the remaining portions of this Policy.

29. Entirety Agreement. This Policy reflects the entire agreement between the Parties with regard to the subject matter hereof. No Party has made any promises, guarantees or assurances with respect to the subject matter hereof except as contained herein.

Exhibit 5.1-5


RIO VISTA GP LLC

VOTING AGREEMENT

______________, 2004


VOTING AGREEMENT

This Voting Agreement (this "AGREEMENT") is entered into as of ____________, 2004, by and among Rio Vista GP LLC, a Delaware limited liability company (the "COMPANY"), Penn Octane Corporation, a Delaware corporation and member of the Company ("PENN OCTANE"), and the members of the Company identified on the signature page of this Agreement (collectively, the "MEMBERS" and, individually, each a "MEMBER"). The Company, Penn Octane and the Members are sometimes referred to herein, collectively, as the "parties" and, individually, as a "party" to this Agreement. Unless otherwise provided, capitalized terms used in this Agreement have the meanings ascribed to them in Section 5 hereof.

RECITALS

WHEREAS, immediately prior to the date hereof, Penn Octane was the owner of on hundred percent (100%) of the limited liability company interests of the Company (the "PENN OCTANE INTEREST").

WHEREAS, pursuant to option agreements dated July 10, 2003, Penn Octane granted each Member the right (the "PURCHASE RIGHT") to purchase twenty-five percent (25%) of the Penn Octane Interest at an exercise price equal to the pro rata portion of the tax basis capital the Partnership (as defined in Section 1.4 of this Agreement) after the distribution of the common units of the Partnership to the stockholders of Penn Octane.

WHEREAS, the exercise of the Purchase Right is conditioned upon the execution and delivery of this Agreement by each Member.

AGREEMENT

NOW, THEREFORE, in consideration of the mutual promises, representations, warranties, covenants, and conditions set forth in this Agreement, the Purchase Right and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the Parties hereby agree as follows:

1. VOTING AGREEMENT.

1.1 Voting by Member for Managers. From and after the date hereof and until the provisions of this Section 1 cease to be effective, at each meeting of the members of the Company, or at any meeting of the members of the Company at which members of the Board of Managers of the Company (the "BOARD") are to be elected, or whenever members of the Board are to be elected by the members of the Company by written consent, each Member agrees to vote or act with respect to all of his, her or its limited liability company interests in the Company and shall take all other necessary or desirable actions within such Member's control whether in such capacity as a Member, manager of the Company, officer of the Company, or otherwise (including, without limitation, attendance at meetings, in person or by proxy, for purposes of


obtaining a quorum and execution of written consents), and the Company agrees to take all necessary and desirable actions within its control, so as to:

1.1.1     fix  the number of members of the Board (the "MANAGERS"
          and  each,  individually,  a  "MANAGER") at such number
          designated  by  Penn  Octane;  and

1.1.2     elect each and every Manager designated by Penn Octane.

1.2 Removal and Substitution of Members of the Board. Each Member agrees to vote or act with respect to all of his, her or its limited liability company interests in the Company for the removal of any member of the Board upon the request of Penn Octane and for the election to the Board of a substitute nominated by Penn Octane in accordance with the provisions of Section 1.1. Each Member agrees that no Manager may be removed from office without the approval of Penn Octane. Each Member further agrees to vote or act with respect to all of his, her or its limited liability company interests in the Company in such manner as shall be necessary or appropriate to ensure that any vacancy on the Board occurring for any reason shall be filled only in accordance with the provisions of Section 1.1.

1.3 Voting by Member on All Other Matters. From and after the date hereof and until the provisions of this Section 1 cease to be effective, at each meeting of the members of the Company, or whenever members of the Company are to take action by written consent, each Member agrees to vote or act with respect to all of his, her or its limited liability company interests in the Company as directed by Penn Octane and shall take all other necessary or desirable actions within such Member's control whether in such capacity as a Member, Manager, officer of the Company, or otherwise (including, without limitation, attendance at meetings, in person or by proxy, for purposes of obtaining a quorum and execution of written consents), and the Company agrees to take all necessary and desirable actions within its control, as directed by Penn Octane.

1.4 Exceptions. The provisions of Section 1.3 of this Agreement do not apply with respect to any matter involving (a) the sale, transfer, assignment, pledge, hypothecation or other disposal of all or any portion of (i) any general partner interest (the "GENERAL PARTNER INTEREST") in Rio Vista Energy Partners L.P., a Delaware limited partnership (the "PARTNERSHIP"), or (ii) any Incentive Distribution Rights (as defined in the First Amended and Restated Agreement of Limited Partnership of Rio Vista Energy Partners L.P. (the "PARTNERSHIP AGREEMENT")) or (b) the merger, consolidation or sale of all or substantially all of the assets of the Partnership, its subsidiaries or the Company.

2. NO REVOCATION. The voting agreements contained herein are coupled with an interest and may not be revoked during the term of this Agreement.

3. LEGEND. Each certificate evidencing limited liability company interests in the Company and each certificate issued in exchange for or upon the Transfer, as defined in Section 5 below, of any limited liability company interests of the Company will be stamped or otherwise imprinted with a legend in substantially the following form:

"THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A VOTING AGREEMENT DATED AS OF ______________, 2004, ENTERED INTO BY AND AMONG THE COMPANY, PENN OCTANE AND CERTAIN OF THE COMPANY'S MEMBERS, AND BY ACCEPTING THESE SECURITIES, THE PERSON ACCEPTING SUCH INTEREST SHALL BE DEEMED TO AGREE TO AND SHALL BECOME BOUND BY ALL THE PROVISIONS OF SAID VOTING AGREEMENT. A COPY OF SUCH VOTING AGREEMENT WILL BE FURNISHED, WITHOUT CHARGE, BY THE COMPANY TO THE HOLDER HEREOF UPON WRITTEN REQUEST."

The Company will imprint such legend on all certificates representing limited liability company interests outstanding prior to the date hereof.

4. TRANSFER. Prior to any Transfer of any limited liability company interest in the Company or any interest therein to any Person, which Transfer is subject to the restrictions set forth in the Agreements, the Member effecting such Transfer will cause the prospective Transferee(s) to execute and deliver to each Party a counterpart of this Agreement.

5. DEFINITIONS. As used in this Agreement, the following terms shall have the meanings set forth below:

5.1 "PERSON" means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization, and a governmental entity or any department, agency, or political subdivision thereof.

5.2 "TRANSFER" means the sale, transfer, assignment, pledge, hypothecation or other disposal.

5.3 "TRANSFEREE" shall mean the recipient of a transfer.

6. MISCELLANEOUS.

6.1 Notices. All notices and other communications required or permitted hereunder shall be in writing and shall be mailed by registered or certified mail, postage prepaid, sent by facsimile or electronic mail or otherwise delivered by hand or by messenger addressed as follows:

(1) if to a Member or Penn Octane, at the Member's or Penn Octane's, as applicable, address, facsimile number or electronic mail address as shown in the Company's records, as may be updated in accordance with the provisions hereof.

(2) if to the Company, one copy should be sent to its address or facsimile number set forth on the signature page of this Agreement and addressed to the attention of the President, or at such other address or facsimile number as the Company shall have furnished to the Members.


Each such notice or other communication shall for all purposes of this Agreement be treated as effective or having been given when delivered if delivered personally, or, if sent by mail, at the earlier of its receipt or 72 hours after the same has been deposited in a regularly maintained receptacle for the deposit of the United States mail, addressed and mailed as aforesaid or, if sent by facsimile, upon confirmation of facsimile transfer.

6.2 Successors and Assigns. Except as otherwise provided herein, the terms and conditions of this Agreement shall inure to the benefit of and be binding upon the respective successors and assigns of the parties. Nothing in this Agreement, express or implied, is intended to confer upon any party other than the parties hereto or their respective successors and assigns any rights, remedies, obligations or liabilities under or by reason of this Agreement, except as expressly provided in this Agreement.

6.3 Severability. In the event that any provision of this Agreement becomes or is declared by a court of competent jurisdiction to be illegal, unenforceable or void, this Agreement shall continue in full force and effect without said provision, and the parties agree to negotiate, in good faith, a legal and enforceable substitute provision which most nearly effects the parties' intent in entering into this Agreement.

6.4 Amendments and Waivers. Any term of this Agreement may be amended and the observance of any term of this Agreement may be waived (either generally or in a particular instance and either retroactively or prospectively), only with the written consent of (i) the Company, (ii) each Member and (iii) Penn Octane. Any such amendment, waiver, discharge or termination effected in accordance with this paragraph shall be binding upon each holder of any securities purchased under this Agreement at the time outstanding (including securities into which such securities have been converted or exchanged or for which such securities have been exercised) and each future holder of all such securities.

6.5 Governing Law. This Agreement shall be governed by and construed under the laws of the State of Delaware as applied to agreements among Delaware residents entered into and to be performed entirely within Delaware.

6.6 Specific Performance. The rights of the parties under this Agreement are unique and, accordingly, the parties shall, in addition to such other remedies as may be available to any of them at law or in equity, have the right to enforce their rights hereunder by actions for specific performance to the extent permitted by law.

6.7 Counterparts. This Agreement may be executed in any number of counterparts, each of which, when so executed and delivered, will be deemed an original, and all such counterparts together will constitute one and the same instrument.

6.8 Conflict. In the event of any conflict between the terms of this Agreement and the Company's Limited Liability Company Agreement, the Partnership Agreement or any other agreement to which the Company, Penn Octane or a Member is bound, the terms of this Agreement will control.

6.9 Attorney's Fees. In the event that any suit or action is instituted to enforce any provision in this Agreement, the prevailing party in such dispute shall be entitled to recover from


the losing party all fees, costs and expenses of enforcing any right of such prevailing party under or with respect to this Agreement, including without limitation, such reasonable fees and expenses of attorneys and accountants, which shall include, without limitation, all fees, costs and expenses of appeals.

6.10 Titles and Subtitles. The titles and subtitles used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement. All references in this Agreement to sections, paragraphs, exhibits and schedules shall, unless otherwise provided, refer to sections and paragraphs hereof and exhibits and schedules attached hereto.

6.11 Entire Agreement. This Agreement constitutes the full and entire understanding and agreement among the parties with regard to the subject matter hereof and supercedes and replaces any prior verbal or written understandings, communications, or representations between the Parties in relation to the subject matter of this Agreement.

6.12 Construction. The parties hereto have participated jointly in the negotiation and drafting of this Agreement. In the event an ambiguity or question of intent or interpretation arises, this Agreement shall be construed as if drafted jointly by the parties hereto and no presumption or burden of proof shall arise favoring or disfavoring any party hereto by virtue of the authorship of any of the provisions of this Agreement. Any reference to any federal, state, local, or foreign statute or law shall be deemed also to refer to all rules and regulations promulgated thereunder, unless the context requires otherwise.

6.13 Delays or Omissions. Except as expressly provided herein, no delay or omission to exercise any right, power or remedy accruing to any party to this Agreement upon any breach or default of any other party under this Agreement shall impair any such right, power or remedy of such non-defaulting party, nor shall it be construed to be a waiver of any such breach or default, or an acquiescence therein, or of or in any similar breach or default thereafter occurring, nor shall any waiver of any single breach or default be deemed a waiver of any other breach or default theretofore or thereafter occurring. Any waiver, permit, consent or approval of any kind or character on the part of any party of any breach or default under this Agreement, or any waiver on the part of any party of any provisions or conditions of this Agreement, must be in writing and shall be effective only to the extent specifically set forth in such writing. All remedies, either under this Agreement or by law or otherwise afforded to any party to this Agreement, shall be cumulative and not alternative.

6.14 Telecopy Execution and Delivery. A facsimile, telecopy or other reproduction of this Agreement may be executed by one or more parties hereto, and an executed copy of this Agreement may be delivered by one or more parties hereto by facsimile or similar electronic transmission device pursuant to which the signature of or on behalf of such party can be seen, and such execution and delivery shall be considered valid, binding and effective for all purposes. At the request of any party hereto, all parties hereto agree to execute an original of this Agreement as well as any facsimile, telecopy or other reproduction hereof.


6.15 Jurisdiction; Venue. With respect to any disputes arising out of or related to this Agreement, the parties consent to the exclusive jurisdiction of, and venue in, the state or federal courts in Harris County in the State of Texas.

6.16 Jury Trial. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING (WHETHER SOUNDING IN CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR RELATED TO THIS AGREEMENT.

6.17 Further Assurances; Instruments. Each of the Members, Penn Octane and the Company agree not to vote any of their respective limited liability interests in the Company, or to take any other actions, that would in any manner defeat, impair, be inconsistent with or adversely affect the rights of the parties under Section 1 of this Agreement. From time to time, each party hereto shall execute and deliver such instruments and documents as may be reasonably necessary to carry out the purposes and intent of this Agreement.

(Signatures on following page.)


IN WITNESS WHEREOF, the undersigned or each of their respective duly authorized officers or representatives have set their hands hereunto effective upon the date first above written.

COMPANY:                                     PENN OCTANE:

RIO VISTA GP LLC                             PENN OCTANE CORPORATION
a Delaware limited liability company         a Delaware corporation


By:                                          By:
   ---------------------------------            --------------------------------
     Richard Shore, Jr.                            Jerome B. Richter
     President                                     Chief Executive Officer
820 Gessner Road
Suite 1250
Houston, Texas  77024                        THE MEMBERS:

                                             SHORE CAPITAL LLC

                                             By:
                                                --------------------------------
                                                   Richard Shore, Jr., President


                                             -----------------------------------
                                             Jerome B. Richter

[Signature Page to Voting Agreement]


FIRST AMENDED AND RESTATED

AGREEMENT OF LIMITED PARTNERSHIP

OF

RIO VISTA OPERATING PARTNERSHIP L.P.


                                TABLE OF CONTENTS

                                                                            PAGE


ARTICLE I     DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . .1
     Section 1.1     Definitions. . . . . . . . . . . . . . . . . . . . . . . .1
     Section 1.2     Construction . . . . . . . . . . . . . . . . . . . . . . .9

ARTICLE II     ORGANIZATION . . . . . . . . . . . . . . . . . . . . . . . . . 10
     Section 2.1     Formation. . . . . . . . . . . . . . . . . . . . . . . . 10
     Section 2.2     Name . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     Section 2.3     Registered Office; Registered Agent; Principal Office;
                     Other Offices. . . . . . . . . . . . . . . . . . . . . . 10
     Section 2.4     Purpose and Business . . . . . . . . . . . . . . . . . . 10
     Section 2.5     Powers . . . . . . . . . . . . . . . . . . . . . . . . . 11
     Section 2.6     Power of Attorney. . . . . . . . . . . . . . . . . . . . 11
     Section 2.7     Term . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     Section 2.8     Title to Partnership Assets. . . . . . . . . . . . . . . 12

ARTICLE III     RIGHTS OF LIMITED PARTNERS. . . . . . . . . . . . . . . . . . 13
     Section 3.1     Limitation of Liability. . . . . . . . . . . . . . . . . 13
     Section 3.2     Management of Business . . . . . . . . . . . . . . . . . 13
     Section 3.3     Outside Activities of the Limited Partners . . . . . . . 13
     Section 3.4     Rights of Limited Partners . . . . . . . . . . . . . . . 13

ARTICLE IV     TRANSFERS OF PARTNERSHIP INTERESTS . . . . . . . . . . . . . . 14
     Section 4.1     Transfer Generally . . . . . . . . . . . . . . . . . . . 14
     Section 4.2     Transfer of General Partner's General Partner
                     Interest . . . . . . . . . . . . . . . . . . . . . . . . 15
     Section 4.3     Transfer of a Limited Partner's Partnership Interest . . 15
     Section 4.4     Restrictions on Transfers. . . . . . . . . . . . . . . . 15

ARTICLE V     CAPITAL CONTRIBUTIONS AND ISSUANCE OF PARTNERSHIP INTERESTS . . 16
     Section 5.1     Initial Contributions. . . . . . . . . . . . . . . . . . 16
     Section 5.2     Contributions Pursuant to the Contribution Agreement . . 16
     Section 5.3     Additional Capital Contributions . . . . . . . . . . . . 16
     Section 5.4     Interest and Withdrawal. . . . . . . . . . . . . . . . . 16
     Section 5.5     Capital Accounts . . . . . . . . . . . . . . . . . . . . 17


                                      -i-

                                TABLE OF CONTENTS
                                  (continued)

                                                                            PAGE

     Section 5.6     Loans from Partners. . . . . . . . . . . . . . . . . . . 19
     Section 5.7     Issuances of Additional Partnership Securities . . . . . 19
     Section 5.8     Limited Preemptive Rights. . . . . . . . . . . . . . . . 20
     Section 5.9     Fully Paid and Non-Assessable Nature of Limited
                     Partner Interests. . . . . . . . . . . . . . . . . . . . 20

ARTICLE VI     ALLOCATIONS AND DISTRIBUTIONS. . . . . . . . . . . . . . . . . 21
     Section 6.1     Allocations for Capital Account Purposes . . . . . . . . 21
     Section 6.2     Allocations for Tax Purposes . . . . . . . . . . . . . . 24
     Section 6.3     Distributions. . . . . . . . . . . . . . . . . . . . . . 26

ARTICLE VII     MANAGEMENT AND OPERATION OF BUSINESS. . . . . . . . . . . . . 27
     Section 7.1     Management . . . . . . . . . . . . . . . . . . . . . . . 27
     Section 7.2     Certificate of Limited Partnership . . . . . . . . . . . 29
     Section 7.3     Restrictions on the General Partner's Authority. . . . . 29
     Section 7.4     Reimbursement of the General Partner . . . . . . . . . . 30
     Section 7.5     Outside Activities . . . . . . . . . . . . . . . . . . . 30
     Section 7.6     Loans from the General Partner; Loans or
                     Contributions from the Partnership; Contracts
                     with Affiliates; Certain Restrictions on the General
                     Partner. . . . . . . . . . . . . . . . . . . . . . . . . 31
     Section 7.7     Indemnification. . . . . . . . . . . . . . . . . . . . . 33
     Section 7.8     Liability of Indemnitees . . . . . . . . . . . . . . . . 35
     Section 7.9     Resolution of Conflicts of Interest. . . . . . . . . . . 35
     Section 7.10    Other Matters Concerning the General Partner . . . . . . 37
     Section 7.11    Reliance by Third Parties. . . . . . . . . . . . . . . . 37

ARTICLE VIII     BOOKS, RECORDS AND ACCOUNTING. . . . . . . . . . . . . . . . 38
     Section 8.1     Records and Accounting . . . . . . . . . . . . . . . . . 38
     Section 8.2     Fiscal Year. . . . . . . . . . . . . . . . . . . . . . . 38

ARTICLE IX     TAX MATTERS. . . . . . . . . . . . . . . . . . . . . . . . . . 38
     Section 9.1     Tax Returns and Information. . . . . . . . . . . . . . . 38
     Section 9.2     Tax Elections. . . . . . . . . . . . . . . . . . . . . . 39
     Section 9.3     Tax Controversies. . . . . . . . . . . . . . . . . . . . 39
     Section 9.4     Withholding. . . . . . . . . . . . . . . . . . . . . . . 39

ARTICLE X     ADMISSION OF PARTNERS . . . . . . . . . . . . . . . . . . . . . 39


                                      -ii-

                                TABLE OF CONTENTS
                                  (continued)

                                                                            PAGE

     Section 10.1    Admission of Partners. . . . . . . . . . . . . . . . . . 39
     Section 10.2    Admission of Substituted Limited Partner . . . . . . . . 40
     Section 10.3    Admission of Additional Limited Partners . . . . . . . . 40
     Section 10.4    Admission of Successor or Transferee General Partner . . 40
     Section 10.5    Amendment of Agreement and Certificate of Limited
                     Partnership. . . . . . . . . . . . . . . . . . . . . . . 41

ARTICLE XI     WITHDRAWAL OR REMOVAL OF PARTNERS. . . . . . . . . . . . . . . 41
     Section 11.1    Withdrawal of the General Partner. . . . . . . . . . . . 41
     Section 11.2    Removal of the General Partner . . . . . . . . . . . . . 42
     Section 11.3    Interest of Departing Partner. . . . . . . . . . . . . . 43
     Section 11.4    Withdrawal of a Limited Partner. . . . . . . . . . . . . 43

ARTICLE XII     DISSOLUTION AND LIQUIDATION . . . . . . . . . . . . . . . . . 43
     Section 12.1    Dissolution. . . . . . . . . . . . . . . . . . . . . . . 43
     Section 12.2    Continuation of the Business of the Partnership After
                     Dissolution. . . . . . . . . . . . . . . . . . . . . . . 44
     Section 12.3    Liquidator . . . . . . . . . . . . . . . . . . . . . . . 45
     Section 12.4    Liquidation. . . . . . . . . . . . . . . . . . . . . . . 45
     Section 12.5    Cancellation of Certificate of Limited Partnership . . . 46
     Section 12.6    Return of Contributions. . . . . . . . . . . . . . . . . 46
     Section 12.7    Waiver of Partition. . . . . . . . . . . . . . . . . . . 46
     Section 12.8    Capital Account Restoration. . . . . . . . . . . . . . . 46

ARTICLE XIII     AMENDMENT OF PARTNERSHIP AGREEMENT . . . . . . . . . . . . . 47
     Section 13.1    Amendment to be Adopted Solely by the General
                     Partner. . . . . . . . . . . . . . . . . . . . . . . . . 47
     Section 13.2    Amendment Procedures . . . . . . . . . . . . . . . . . . 48

ARTICLE XIV     MERGER. . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
     Section 14.1    Authority. . . . . . . . . . . . . . . . . . . . . . . . 48
     Section 14.2    Procedure for Merger or Consolidation. . . . . . . . . . 48
     Section 14.3    Approval by Limited Partners of Merger or
                     Consolidation. . . . . . . . . . . . . . . . . . . . . . 49
     Section 14.4    Certificate of Merger. . . . . . . . . . . . . . . . . . 50
     Section 14.5    Effect of Merger . . . . . . . . . . . . . . . . . . . . 50

ARTICLE XV     GENERAL PROVISIONS . . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.1    Addresses and Notices. . . . . . . . . . . . . . . . . . 51


                                      -iii-

                                TABLE OF CONTENTS
                                  (continued)

                                                                            PAGE

     Section 15.2    Further Action . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.3    Binding Effect . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.4    Integration. . . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.5    Creditors. . . . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.6    Waiver . . . . . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.7    Counterparts . . . . . . . . . . . . . . . . . . . . . . 51
     Section 15.8    Applicable Law . . . . . . . . . . . . . . . . . . . . . 52
     Section 15.9    Invalidity of Provisions . . . . . . . . . . . . . . . . 52
     Section 15.10   Consent of Partners. . . . . . . . . . . . . . . . . . . 52

-iv-

FIRST AMENDED AND RESTATED
AGREEMENT OF LIMITED PARTNERSHIP
OF
RIO VISTA OPERATING PARTNERSHIP L.P.

This FIRST AMENDED AND RESTATED AGREEMENT OF LIMITED PARTNERSHIP of RIO
VISTA OPERATING PARTNERSHIP L.P., dated as of September 16, 2004 (this "Agreement"), is entered into by and between Rio Vista Operating GP LLC, a Delaware limited liability company, as the General Partner, Penn Octane Corporation, a Delaware corporation, and, upon consummation of the transactions contemplated under Section 5.2 of this Agreement, Rio Vista Energy Partners L.P., a Delaware limited partnership, as the Limited Partners, together with any other Persons who hereafter become Partners in the Partnership or parties hereto as provided herein. This Agreement amends and restates the Agreement of Limited Partnership of the Partnership dated July, 10, 2003, in its entirety.

ARTICLE I

DEFINITIONS

Section 1.1 Definitions. The following definitions shall be for all purposes, unless otherwise clearly indicated to the contrary, applied to the terms used in this Agreement. Capitalized terms used herein but not otherwise defined shall have the meanings assigned to such terms in the MLP Agreement.

"Additional Limited Partner" means a Person admitted to the Partnership as a Limited Partner pursuant to Section 10.3 and who is s such on the books and records of the Partnership.

"Adjusted Capital Account" means the Capital Account maintained for each Partner as of the end of each fiscal year of the Partnership, (a) increased by any amounts that such Partner is obligated to restore under the standards set by Treasury Regulation Section 1.704-1(b)(2)(ii)(c) (or is deemed obligated to restore under Treasury Regulation Sections 1.704-2(g) and 1.704-2(i)(5)) and (b) decreased by (i) the amount of all losses and deductions that, as of the end of such fiscal year, are reasonably expected to be allocated to such Partner in subsequent years under Sections 704(e)(2) and 706(d) of the Code and Treasury Regulation Section 1.751-1(b)(2)(ii), and (ii) the amount of all distributions that, as of the end of such fiscal year, are reasonably expected to be made to such Partner in subsequent years in accordance with the terms of this Agreement or otherwise to the extent they exceed offsetting increases to such Partner's Capital Account that are reasonably expected to occur during (or prior to) the year in which such distributions are reasonably expected to be made (other than increases as a result of a minimum gain chargeback pursuant to Section 6.1(d)(i) or 6.1(d)(ii)). The foregoing definition of Adjusted Capital Account is intended to comply with the provisions of Treasury Regulation Section 1.704-1(b)(2)(ii)(d) and shall be interpreted consistently therewith. The "Adjusted Capital Account" of a Partner in respect of a General Partner Interest or any other specified interest in the Partnership shall be the amount that such Adjusted Capital Account would be if such General Partner Interest or other interest in the Partnership were the only interest in the Partnership held by such Partner

1

from and after the date on which such General Partner Interest or other interest in the Partnership was first issued.

"Adjusted Property" means any property the Carrying Value of which has been adjusted pursuant to Section 5.5(d)(i) or 5.5(d)(ii).

"Affiliate" means, with respect to any Person, any other Person that directly or indirectly through one or more intermediaries controls, is controlled by or is under common control with, the Person in question. As used herein, the term "control" means the possession, direct or indirect, of the power to direct or cause the direction of the management and policies of a Person, whether through ownership of voting securities, by contract or otherwise.

"Agreed Allocation" means any allocation, other than a Required Allocation, of an item of income, gain, loss or deduction pursuant to the provisions of
Section 6.1, including, without limitation, a Curative Allocation (if appropriate to the context in which the term "Agreed Allocation" is used).

"Agreed Value" of any Contributed Property means the fair market value of such property or other consideration at the time of contribution as determined by the General Partner using such reasonable method of valuation as it may adopt. The General Partner shall, in its discretion, use such method as it deems reasonable and appropriate to allocate the aggregate Agreed Value of Contributed Properties contributed to the Partnership in a single or integrated transaction among each separate property on a basis proportional to the fair market value of each Contributed Property.

"Agreement" means this Agreement of Limited Partnership of Rio Vista Operating Partnership L.P., as it may be amended, supplemented restated from time to time.

"Assets" means all assets conveyed, contributed or otherwise transferred to the Partnership Group pursuant to the Contribution Agreement.

"Assignee" means a Person to whom one or more Limited Partner Interests have been transferred in a manner permitted under this Agreement, but who has not been admitted as a Substituted Limited.

"Associate" means, when used to indicate a relationship with any Person,
(a) any corporation or organization of which such Person is a director, officer or partner or is, directly or indirectly, the owner of 20% or more of any class of voting stock or other voting interest; (b) any trust or other estate in which such Person has at least a 20% beneficial interest or as to which such Person serves as trustee or in a similar fiduciary capacity; and (c) any relative or spouse of such Person, or any relative of such spouse, who has the same principal residence as such Person.

"Available Cash" means, with respect to any Quarter ending prior to the Liquidation Date:

2

(a) the sum of (i) all cash and cash equivalents of the Partnership on hand at the end of such Quarter, and (ii) all additional cash and cash equivalents of the Partnership on hand on the date of determination of Available Cash with respect to such Quarter resulting from Working Capital Borrowings made subsequent to the end of such Quarter, less

(b) the amount of any cash reserves that is necessary or appropriate in the reasonable discretion of the General Partner to (i) provide for the proper conduct of the business of the Partnership (including reserves for future capital expenditures and for anticipated future credit needs of the Partnership) subsequent to such Quarter, (ii) comply with applicable law or any loan agreement, security agreement, mortgage, debt instrument or other agreement or obligation to which any Group Member is a party or by which it is bound or its assets are subject or (iii) provide funds for distributions under Section 6.4 or 6.5 of the MLP Agreement in respect of any one or more of the next four Quarters; provided, however, that the General Partner may not establish cash reserves pursuant to (iii) above if the effect of such reserves would be that the MLP is unable to distribute the Minimum Quarterly Distribution on all Common Units, plus any Cumulative Common Unit Arrearage on all Common Units, with respect to such Quarter; and, provided further, that disbursements made by a Group Member or cash reserves established, increased or reduced after the end of such Quarter but on or before the date of determination of Available Cash with respect to such Quarter shall be deemed to have been made, established, increased or reduced, for purposes of determining Available Cash, within such Quarter if the General Partner so determines.

Notwithstanding the foregoing, "Available Cash" with respect to the Quarter in which the Liquidation Date occurs and any subsequent Quarter shall equal zero.

"Book-Tax Disparity" means with respect to any item of Contributed Property or Adjusted Property, as of the date of any determination, the difference between the Carrying Value of such Contributed Property or Adjusted Property and the adjusted basis thereof for federal income tax purposes as of such date. A Partner's share of the Partnership's Book-Tax Disparities in all of its Contributed Property and Adjusted Property will be reflected by the difference between such Partner's Capital Account balance as maintained pursuant to Section 5.5 and the hypothetical balance of such Partner's Capital Account computed as

if it had been maintained strictly in accordance with federal income tax accounting principles.

"Capital Account" means the capital account maintained for a Partner pursuant to Section 5.5 . The "Capital Account" of a Partner in respect of a General Partner Interest or any other Partnership Interest shall be the amount that such Capital Account would be if such General Partner Interest or other specified interest in the Partnership were the only interest in the Partnership held by such Partner from and after the date on which such General Partner Interest or other specified interest in the Partnership was first issued.

"Capital Contribution" means any cash, cash equivalents or the Net Agreed Value of Contributed Property that a Partner contributes to the Partnership pursuant to this Agreement or the Contribution Agreement.

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"Carrying Value" means (a) with respect to a Contributed Property, the Agreed Value of such property reduced (but not below zero) by all depreciation, amortization and cost recovery deductions charged to the Partners' and Assignees' Capital Accounts in respect of such Contributed Property, and (b) with respect to any other Partnership property, the adjusted basis of such property for federal income tax purposes, all as of the time of determination. The Carrying Value of any property shall be adjusted from time to time in accordance with Sections 5.5(d)(i) and 5.5(d)(ii) and to reflect changes, additions or other adjustments to the Carrying Value for dispositions and acquisitions of Partnership properties, as deemed appropriate by the General Partner.

"Certificate of Limited Partnership" means the Certificate of Limited Partnership of the Partnership filed with the Secretary of State of the State of Delaware as referenced in Section 7.2, as such Certificate of Limited Partnership may be amended, supplemented or restated from time to time.

"Closing Date" means the first date on which the Registration Statement is declared effective by the Commission.

"Code" means the Internal Revenue Code of 1986, as amended and in effect

from time to time. Any reference herein to a specific section or sections of the Code shall be deemed to include a reference to any corresponding provision of any successor law.

"Commission" means the United States Securities and Exchange Commission.

"Contributed Property" means each property or other asset, in such form as may be permitted by the Delaware Act, but excluding cash, contributed to the Partnership. Once the Carrying Value of a Contributed Property is adjusted pursuant to Section 5.5(d), such property shall no longer constitute a Contributed Property, but shall be deemed an Adjusted Property.

"Contribution Agreement" means that certain Contribution, Conveyance and Assumption Agreement among the Partnership, the MLP General Partner, the MLP, and Penn Octane Corporation, together with the additional conveyance documents and instruments contemplated or referenced thereunder.

"Curative Allocation" means any allocation of an item of income, gain, deduction, loss or credit pursuant to the provisions of Section 6.1(d)(ix).

"Delaware Act" means the Delaware Revised Uniform Limited Partnership Act, 6 Del. C. Section 17-101 et seq., as amended, supplemented or restated from time to time, and any successor to such statute.

"Departing Partner" means a former General Partner from and after the effective date of any withdrawal or removal of such former General Partner pursuant to Section 11.1 or 11.2.

"Distribution" means the distribution of Common Units of the MLP to the stockholders of Penn Octane Corporation, as described in the Registration Statement.

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"Economic Risk of Loss" has the meaning set forth in Treasury Regulation Section 1.752-2(a).

"Event of Withdrawal" has the meaning assigned to such term in Section
11.1(a).

"General Partner" means Rio Vista Operating GP LLC and its successors and permitted assigns as general partner of the Partnership.

"General Partner Interest" means the ownership interest of the General Partner in the Partnership (in its capacity as a general partner) and includes any and all benefits to which the General Partner is entitled as provided in this Agreement, together with all obligations of the General Partner to comply with the terms and provisions of this Agreement.

"Group Member" means a member of the Partnership Group.

"Indemnitee" means (a) the General Partner, (b) any Departing Partner, (c) any Person who is or was an Affiliate of the General Partner or any Departing Partner, (d) any Person who is or was a member, partner, officer, director, employee, agent or trustee of any Group Member, the General Partner or any Departing Partner or any Affiliate of any Group Member, the General Partner or any Departing Partner, and (e) any Person who is or was serving at the request of the General Partner or any Departing Partner or any Affiliate of the General Partner or any Departing Partner as an officer, director, employee, member, partner, agent, fiduciary or trustee of another Person; provided, that a Person shall not be an Indemnitee by reason of providing, on a fee-for-services basis, trustee, fiduciary or custodial services.

"Limited Partner" means any Person that is admitted to the Partnership as a limited partner pursuant to the terms and conditions of this Agreement; but the term "Limited Partner" shall not include any Person from and after the time such Person withdraws as a Limited Partner from the Partnership.

"Limited Partner Interest" means the ownership interest of a Limited Partner or Assignee in the Partnership and includes any and all benefits to which such Limited Partner or Assignee is entitled as provided in this Agreement, together with all obligations of such Limited Partner or Assignee to comply with the terms and provisions of this Agreement.

"Liquidation Date" means (a) in the case of an event giving rise to the dissolution of the Partnership of the type described in clauses (a) and (b) of the first sentence of Section 12.2, the date on which the applicable time period during which the Partners have the right to elect to reconstitute the Partnership and continue its business has expired without such an election being made, and (b) in the case of any other event giving rise to the dissolution of the Partnership, the date on which such event occurs.

"Liquidator" means one or more Persons selected by the General Partner to perform the functions described in Section 12.3 as liquidating trustee of the Partnership within the meaning of the Delaware Act.

"Merger Agreement" has the meaning assigned to such term in Section 14.1.

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"MLP" means Rio Vista Energy Partners L.P., a Delaware limited partnership.

"MLP Agreement" means the Agreement of Limited Partnership of Rio Vista Energy Partners L.P., as it may be amended, supplemented or restated from time to time.

"MLP General Partner" means Rio Vista GP LLC, a Delaware limited liability company and the general partner of the MLP.

"Net Agreed Value" means, (a) in the case of any Contributed Property, the Agreed Value of such property reduced by any liabilities either assumed by the Partnership upon such contribution or to which such property is subject when contributed, and (b) in the case of any property distributed to a Partner or Assignee by the Partnership, the Partnership's Carrying Value of such property (as adjusted pursuant to Section 5.5(d)(ii)) at the time such property is distributed, reduced by any indebtedness either assumed by such Partner or Assignee upon such distribution or to which such property is subject at the time of distribution, in either case, as determined under Section 752 of the Code.

"Net Income" means, for any taxable year, the excess, if any, of the Partnership's items of income and gain (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year over the Partnership's items of loss and deduction (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year. The items included in the calculation of Net Income shall be determined in accordance with Section 5.5(b) and shall not include any items specially allocated under Section 6.1(d).

"Net Loss" means, for any taxable year, the excess, if any, of the Partnership's items of loss and deduction (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year over the Partnership's items of income and gain (other than those items taken into account in the computation of Net Termination Gain or Net Termination Loss) for such taxable year.

The items included in the calculation of Net Loss shall be determined in accordance with Section 5.5(b) and shall not include any items specially allocated under Section 6.1(d).

"Net Termination Gain" means, for any taxable year, the sum, if positive, of all items of income, gain, loss or deduction recognized by the Partnership after the Liquidation Date. The items included in the determination of Net Termination Gain shall be determined in accordance with Section 5.5(b) and shall not include any items of income, gain or loss specially allocated under Section 6.1(d).

"Net Termination Loss" means, for any taxable year, the sum, if negative, of all items of income, gain, loss or deduction recognized by the Partnership after the Liquidation Date. The items included in the determination of Net Termination Loss shall be determined in accordance with Section 5.5(b) and shall not include any items of income, gain or loss specially allocated under Section 6.1(d).

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"Nonrecourse Built-in Gain" means with respect to any Contributed Properties or Adjusted Properties that are subject to a mortgage or pledge securing a Nonrecourse Liability, the amount of any taxable gain that would be allocated to the Partners pursuant to Sections 6.2(b)(i)(A), 6.2(b)(ii)(A) and 6.2(b)(iii) if such properties were disposed of in a taxable transaction in full satisfaction of such liabilities and for no other consideration.

"Nonrecourse Deductions" means any and all items of loss, deduction or expenditure (including, without limitation, any expenditure described in Section 705(a)(2)(B) of the Code) that, in accordance with the principles of Treasury Regulation Section 1.704-2(b), are attributable to a Nonrecourse Liability.

"Nonrecourse Liability" has the meaning set forth in Treasury Regulation Section 1.752-1(a)(2).

"OLP Subsidiary" means a Subsidiary of the Partnership.

"Omnibus Agreement" means that Omnibus Agreement, dated as of the Closing Date, among the Partnership, Penn Octane Corporation, the MLP General Partner and the MLP.

"Opinion of Counsel" means a written opinion of counsel (who may be regular counsel to the Partnership or the General Partner or any of its Affiliates) acceptable to the General Partner in its reasonable discretion.

"Partner Nonrecourse Debt" has the meaning set forth in Treasury Regulation Section 1.704-2(b)(4).

"Partner Nonrecourse Debt Minimum Gain" has the meaning set forth in Treasury Regulation Section 1.704-2(i)(2).

"Partner Nonrecourse Deductions" means any and all items of loss, deduction or expenditure (including, without limitation, any expenditure described in
Section 705(a)(2)(B) of the Code) that, in accordance with the principles of Treasury Regulation Section 1.704-2(i), are attributable to a Partner Nonrecourse Debt.

"Partners" means the General Partner and the Limited Partners.

"Partnership" means Rio Vista Operating Partnership L.P., a Delaware limited partnership, and any successors thereto.

"Partnership Group" means the Partnership and all OLP Subsidiaries, treated as a single consolidated entity.

"Partnership Interest" means an ownership interest of a Partner in the Partnership, which shall include the General Partner Interest and the Limited Partner Interest(s).

"Partnership Minimum Gain" means that amount determined in accordance with the principles of Treasury Regulation Section 1.704-2(d).

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"Partnership Security" means any class or series of equity interest in the Partnership (but excluding any options, rights, warrants and appreciation rights relating to an equity interest in the Partnership).

"Percentage Interest" means the percentage interest in the Partnership owned by each Partner upon completion of the transactions in Section 5.2 and shall mean, (a) as to the General Partner, 0.10% and (b) as to the MLP, 99.90%.

"Person" means an individual or a corporation, limited liability company, partnership, joint venture, trust, unincorporated organization, association, government agency or political subdivision thereof or other entity.

"Quarter" means, unless the context requires otherwise, a fiscal quarter (or, with respect to the fiscal quarter during which the Closing Date occurs, the portion of such fiscal quarter remaining after the Closing Date) of the Partnership.

"Recapture Income" means any gain recognized by the Partnership (computed without regard to any adjustment required by Section 734 or Section 743 of the Code) upon the disposition of any property or asset of the Partnership, which gain is characterized as ordinary income because it represents the recapture of deductions previously taken with respect to such property or asset.

"Registration Statement" means the Registration Statement on Form 10 (File No. 0-50394 as it has been or as it may be amended or supplemented from time to time, filed by the MLP with the Commission under the Securities Act to register the distribution of the Common Units in the Distribution.

"Required Allocations" means (a) any limitation imposed on any allocation of Net Losses or Net Termination Losses under Section 6.1(b) or 6.1(c)(ii) and
(b) any allocation of an item of income, gain, loss or deduction pursuant to

Section 6.1(d)(i), 6.1(d)(ii), 6.1(d)(iv), 6.1(d)(vii) or 6.1(d)(ix).

"Residual Gain" or "Residual Loss" means any item of gain or loss, as the case may be, of the Partnership recognized for federal income tax purposes resulting from a sale, exchange or other disposition of a Contributed Property or an Adjusted Property, to the extent such item of gain or loss is not allocated pursuant to Section 6.2(b)(i)(A) or 6.2(b)(ii)(A), respectively, to eliminate Book-Tax Disparities.

"Securities Act" means the Securities Act of 1933, as amended, supplemented or restated from time to time and any successor to such statute.

"Subsidiary" means, with respect to any Person, (a) a corporation of which more than 50% of the voting power of shares entitled (without regard to the occurrence of any contingency) to vote in the election of directors or other governing body of such corporation is owned, directly or indirectly, at the date of determination, by such Person, by one or more Subsidiaries of such Person or a combination thereof, (b) a partnership (whether general or limited) in which such Person or a Subsidiary of such Person is, at the date of determination, a general or limited partner

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of such partnership, but only if more than 50% of the partnership interests of such partnership (considering all of the partnership interests of the partnership as a single class) is owned, directly or indirectly, at the date of determination, by such Person, by one or more Subsidiaries of such Person, or a combination thereof, or (c) any other Person (other than a corporation or a partnership) in which such Person, one or more Subsidiaries of such Person, or a combination thereof, directly or indirectly, at the date of determination, has
(i) at least a majority ownership interest or (ii) the power to elect or direct the election of a majority of the directors or other governing body of such Person.

"Substituted Limited Partner" means a Person who is admitted as a Limited Partner to the Partnership pursuant to Section 10.2 in place of and with all the rights of a Limited Partner and who is shown as a Limited Partner on the books and records of the Partnership.

"Surviving Business Entity" has the meaning assigned to such term in Section 14.2(b).

"transfer" has the meaning assigned to such term in Section 4.1(a).

"Unrealized Gain" attributable to any item of Partnership property means, as of any date of determination, the excess, if any, of (a) the fair market value of such property as of such date (as determined under Section 5.5(d)) over
(b) the Carrying Value of such property as of such date (prior to any adjustment to be made pursuant to Section 5.5(d) as of such date).

"Unrealized Loss" attributable to any item of Partnership property means, as of any date of determination, the excess, if any, of (a) the Carrying Value of such property as of such date (prior to any adjustment to be made pursuant to
Section 5.5(d) as of such date) over (b) the fair market value of such property as of such date (as determined under Section 5.5(d)).

"U.S. GAAP" means United States Generally Accepted Accounting Principles consistently applied.

"Withdrawal Opinion of Counsel" has the meaning assigned to such term in Section 11.1(b).

"Working Capital Borrowings" means borrowings used solely for working capital purposes or to pay distributions to Partners made pursuant to a credit facility or other arrangement to the extent such borrowings are required to be reduced to a relatively small amount each year (or for the year in which the Distribution is consummated, the 12-month period beginning on the Closing Date) for an economically meaningful period of time.

Section 1.2 Construction. Unless the context requires otherwise: (a) any pronoun used in this Agreement shall include the corresponding masculine, feminine or neuter forms, and the singular form of nouns, pronouns and verbs shall include the plural and vice versa; (b) references to Articles and Sections refer to Articles and Sections of this Agreement; and (c) the term "include" or "includes" means includes, without limitation, and "including" means including, without limitation.

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ARTICLE II

ORGANIZATION

Section 2.1 Formation. Except as expressly provided to the contrary in this Agreement, the rights, duties (including fiduciary duties), liabilities and obligations of the Partners and the administration, dissolution and termination of the Partnership shall be governed by the Delaware Act. All Partnership Interests shall constitute personal property of the owner thereof for all purposes and a Partner has no interest in specific Partnership property.

Section 2.2 Name. The name of the Partnership shall be "Rio Vista

Operating Partnership L.P." The Partnership's business may be conducted under any other name or names deemed necessary or appropriate by the General Partner in its sole discretion, including the name of the General Partner. The words "Limited Partnership," "L.P.," "Ltd." or similar words or letters shall be included in the Partnership's name where necessary for the purpose of complying with the laws of any jurisdiction that so requires. The General Partner in its discretion may change the name of the Partnership at any time and from time to time and shall notify the Limited Partners of such change in the next regular communication to the Limited Partners.

Section 2.3 Registered Office; Registered Agent; Principal Office; Other Offices. Unless and until changed by the General Partner, the registered office of the Partnership in the State of Delaware shall be located at 615 South DuPont Highway, Dover, DE 19901, and the registered agent for service of process on the Partnership in the State of Delaware at such registered office shall be Capitol Services, Inc. The principal office of the Partnership shall be located at 820 Gessner Road, Suite 1285, Houston, Texas 77024, or such other place as the General Partner may from time to time designate by notice to the Limited Partners. The Partnership may maintain offices at such other place or places within or outside the State of Delaware as the General Partner deems necessary or appropriate. The address of the General Partner shall be 820 Gessner Road, Suite 1285, Houston, Texas 77024, or such other place as the General Partner may from time to time designate by notice to the Limited Partners.

Section 2.4 Purpose and Business. The purpose and nature of the business to be conducted by the Partnership shall be to (a) acquire, manage, operate and sell the Assets and any similar assets or properties now or hereafter acquired by the Partnership, (b) engage directly in, or enter into or form any corporation, partnership, joint venture, limited liability company or other arrangement to engage indirectly in, any business activity that the Partnership is permitted to engage in, or any type of business or activity engaged in by the General Partner prior to the Closing Date and, in connection therewith, to exercise all of the rights and powers conferred upon the Partnership pursuant to the agreements relating to such business activity, (c) engage directly in, or enter into or form any corporation, partnership, joint venture, limited liability company or other arrangement to engage indirectly in, any business activity that is approved by the General Partner and that lawfully may be conducted by a limited partnership organized pursuant to the Delaware Act and, in connection therewith, to exercise all of the rights and powers conferred upon the Partnership pursuant to the agreements relating to such business activity; provided, however, that the General Partner reasonably determines, as of the date of the acquisition or commencement of such activity, that such activity (i) generates "qualifying

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income" (as such term is defined pursuant to Section 7704 of the Code) or (ii) enhances the operations of an activity of the Partnership that generates qualifying income, and (d) do anything necessary or appropriate to the foregoing, including the making of capital contributions or loans to a Group Member, the MLP or any Subsidiary of the MLP. The General Partner has no obligation or duty to the Partnership, the Limited Partners or the Assignees to propose or approve, and in its discretion may decline to propose or approve, the conduct by the Partnership of any business.

Section 2.5 Powers. The Partnership shall be empowered to do any and all acts and things necessary, appropriate, proper, advisable, incidental to or convenient for the furtherance and accomplishment of the purposes and business described in Section 2.4 and for the protection and benefit of the Partnership.

Section 2.6 Power of Attorney.

(a) Each Limited Partner and each Assignee hereby constitutes and appoints the General Partner and, if a Liquidator shall have been selected pursuant to Section 12.3, the Liquidator (and any successor to the Liquidator by merger, transfer, assignment, election or otherwise) and each of their authorized officers and attorneys-in-fact, as the case may be, with full power of substitution, as its true and lawful agent and attorney-in-fact, with full power and authority in his name, place and stead, to:

(i) execute, swear to, acknowledge, deliver, file and record in the appropriate public offices (A) all certificates, documents and other instruments (including this Agreement and the Certificate of Limited Partnership and all amendments or restatements hereof or thereof) that the General Partner or the Liquidator deems necessary or appropriate to form, qualify or continue the existence or qualification of the Partnership as a limited partnership (or a partnership in which the limited partners have limited liability) in the State of Delaware and in all other jurisdictions in which the Partnership may conduct business or own property; (B) all certificates, documents and other instruments that the General Partner or the Liquidator deems necessary or appropriate to reflect, in accordance with its terms, any amendment, change, modification or restatement of this Agreement; (C) all certificates, documents and other instruments (including conveyances and a certificate of cancellation) that the General Partner or the Liquidator deems necessary or appropriate to reflect the dissolution and liquidation of the Partnership pursuant to the terms of this Agreement; (D) all certificates, documents and other instruments relating to the admission, withdrawal, removal or substitution of any Partner pursuant to, or other events described in, Article IV, X, XI or XII; (E) all certificates, documents and other instruments relating to the determination of the rights, preferences and privileges of any class or series of Partnership Interests issued pursuant hereto; and (F) all certificates, documents and other instruments (including agreements and a certificate of merger) relating to a merger or consolidation of the Partnership pursuant to Article XIV; and

(ii) execute, swear to, acknowledge, deliver, file and record all ballots, consents, approvals, waivers, certificates, documents and other instruments necessary or appropriate, in the discretion of the General Partner or the Liquidator, to make, evidence, give, confirm or ratify any vote, consent, approval, agreement or other action that is made or given by

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the Partners hereunder or is consistent with the terms of this Agreement or is necessary or appropriate, in the discretion of the General Partner or the Liquidator, to effectuate the terms or intent of this Agreement; provided, that when required by any provision of this Agreement that establishes a percentage of the Limited Partners or of the Limited Partners of any class or series required to take any action, the General Partner and the Liquidator may exercise the power of attorney made in this Section 2.6(a)(ii) only after the necessary vote, consent or approval of the Limited Partners or of the Limited Partners of such class or series, as applicable.

Nothing contained in this Section 2.6(a) shall be construed as authorizing the General Partner to amend this Agreement except in accordance with Article XIII or as may be otherwise expressly provided for in this Agreement.

(b) The foregoing power of attorney is hereby declared to be irrevocable and a power coupled with an interest, and it shall survive and, to the maximum extent permitted by law, not be affected by the subsequent death, incompetency, disability, incapacity, dissolution, bankruptcy or termination of any Limited Partner or Assignee and the transfer of all or any portion of such Limited Partner's or Assignee's Partnership Interest and shall extend to such Limited Partner's or Assignee's heirs, successors, assigns and personal representatives. Each such Limited Partner or Assignee hereby agrees to be bound by any representation made by the General Partner or the Liquidator acting in good faith pursuant to such power of attorney; and each such Limited Partner or Assignee, to the maximum extent permitted by law, hereby waives any and all defenses that may be available to contest, negate or disaffirm the action of the General Partner or the Liquidator taken in good faith under such power of attorney. Each Limited Partner or Assignee shall execute and deliver to the General Partner or the Liquidator, within 15 days after receipt of the request therefor, such further designation, powers of attorney and other instruments as the General Partner or the Liquidator deems necessary to effectuate this Agreement and the purposes of the Partnership.

Section 2.7 Term. The term of the Partnership commenced upon the

filing of the Certificate of Limited Partnership in accordance with the Delaware Act and shall continue in existence until the dissolution of the Partnership in accordance with the provisions of Article XII. The existence of the Partnership as a separate legal entity shall continue until the cancellation of the Certificate of Limited Partnership as provided in the Delaware Act.

Section 2.8 Title to Partnership Assets. Title to Partnership assets, whether real, personal or mixed and whether tangible or intangible, shall be deemed to be owned by the Partnership as an entity, and no Partner or Assignee, individually or collectively, shall have any ownership interest in such Partnership assets or any portion thereof. Title to any or all of the Partnership assets may be held in the name of the Partnership, the General Partner, one or more of its Affiliates or one or more nominees, as the General Partner may determine. The General Partner hereby declares and warrants that any Partnership assets for which record title is held in the name of the General Partner or one or more of its Affiliates or one or more nominees shall be held by the General Partner or such Affiliate or nominee for the use and benefit of the Partnership in accordance with the provisions of this Agreement; provided, however, that the General Partner shall use reasonable efforts to cause record title to such assets (other than those assets in respect of which the General Partner determines that the expense and difficulty of

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conveyancing makes transfer of record title to the Partnership impracticable) to be vested in the Partnership as soon as reasonably practicable; provided, further, that, prior to any withdrawal or removal of the General Partner or as soon thereafter as practicable, the General Partner shall use reasonable efforts to effect the transfer of record title to the Partnership and, prior to any such transfer, will provide for the use of such assets in a manner satisfactory to the General Partner. All Partnership assets shall be recorded as the property of the Partnership in its books and records, irrespective of the name in which record title to such Partnership assets is held.

ARTICLE III

RIGHTS OF LIMITED PARTNERS

Section 3.1 Limitation of Liability. The Limited Partners and the Assignees shall have no liability under this Agreement except as expressly provided in this Agreement or the Delaware Act.

Section 3.2 Management of Business. No Limited Partner or Assignee, in its capacity as such, shall participate in the operation, management or control (within the meaning of the Delaware Act) of the Partnership's business, transact any business in the Partnership's name or have the power to sign documents for or otherwise bind the Partnership. Any action taken by any Affiliate of the General Partner or any officer, director, employee, manager, member, general partner, agent or trustee of the General Partner or any of its Affiliates, or any officer, director, employee, manager, member, general partner, agent or trustee of a Group Member, in its capacity as such, shall not be deemed to be participation in the control of the business of the Partnership by a limited partner of the Partnership (within the meaning of Section 17-303(a) of the Delaware Act) and shall not affect, impair or eliminate the limitations on the liability of the Limited Partners or Assignees under this Agreement.

Section 3.3 Outside Activities of the Limited Partners. Subject to the provisions of Article II and the Omnibus Agreement, which shall continue to be applicable to the Persons referred to therein, regardless of whether such Persons shall also be Limited Partners or Assignees, any Limited Partner or Assignee shall be entitled to and may have business interests and engage in business activities in addition to those relating to the Partnership, including business interests and activities in direct competition with the Partnership Group. Neither the Partnership nor any of the other Partners or Assignees shall have any rights by virtue of this Agreement in any business ventures of any Limited Partner or Assignee.

Section 3.4 Rights of Limited Partners.

(a) In addition to other rights provided by this Agreement or by applicable law, and except as limited by Section 3.4(b), each Limited Partner shall have the right, for a purpose reasonably related to such Limited Partner's interest as a limited partner in the Partnership, upon reasonable written demand and at such Limited Partner's own expense:

(i) promptly after becoming available, to obtain a copy of the Partnership's federal, state and local income tax returns for each year;

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(ii) to have furnished to him a current list of the name and last known business, residence or mailing address of each Partner;

(iii) to have furnished to him a copy of this Agreement and the Certificate of Limited Partnership and all amendments thereto, together with a copy of the executed copies of all powers of attorney pursuant to which this Agreement, the Certificate of Limited Partnership and all amendments thereto have been executed;

(iv) to obtain true and full information regarding the amount of cash and a description and statement of the Net Agreed Value of any other Capital Contribution by each Partner and that each Partner has agreed to contribute in the future, and the date on which each became a Partner; and

(v) to obtain such other information regarding the affairs of the Partnership as is just and reasonable; and

(vi) to obtain true and full information regarding the status of the business and financial condition of the Partnership.

(b) The General Partner may keep confidential from the Limited Partners and Assignees, for such period of time as the General Partner deems reasonable, (i) any information that the General Partner reasonably believes to be in the nature of trade secrets or (ii) other information the disclosure of which the General Partner in good faith believes (A) is not in the best interests of the MLP or the Partnership Group, (B) could damage the MLP or the Partnership Group or (C) that any Group Member is required by law or by agreement with any third party to keep confidential (other than agreements with Affiliates of the Partnership the primary purpose of which is to circumvent the obligations set forth in this Section 3.4).

ARTICLE IV

TRANSFERS OF PARTNERSHIP INTERESTS

Section 4.1 Transfer Generally.

(a) The term "transfer," when used in this Agreement with respect to a Partnership Interest, shall be deemed to refer to a transaction by which a General Partner assigns its General Partner Interest to another Person who becomes the General Partner or by which the holder of a Limited Partner Interest assigns such Limited Partner Interest to another Person who is or becomes a Limited Partner (or an Assignee), and includes a sale, assignment, gift, pledge, encumbrance, hypothecation, mortgage, exchange or any other disposition by law or otherwise.

(b) No Partnership Interest shall be transferred, in whole or in part, except in accordance with the terms and conditions set forth in this Article IV. Any transfer or purported transfer of a Partnership Interest not made in accordance with this Article IV shall be null and void.

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(c) Nothing contained in this Agreement shall be construed to prevent a disposition by any member of the General Partner of any or all of the issued and outstanding member interests of the General Partner.

Section 4.2 Transfer of General Partner's General Partner Interest. No provision of this Agreement shall be construed to prevent (and the Limited Partners do hereby expressly consent to) (i) the transfer by the General Partner of all or a portion of its General Partner Interest to one or more Affiliates, which transferred General Partner Interest, to the extent not transferred to a successor General Partner, shall constitute a Limited Partner Interest or (ii) the transfer by the General Partner, in whole and not in part, of its General Partner Interest upon (a) its merger, consolidation or other combination into any other Person or the transfer by it of all or substantially all of its assets to another Person or (b) sale of all or substantially all of the membership interests of the General Partner by its members if, in the case of a transfer described in either clause (i) or (ii) of this sentence, the rights and duties of the General Partner with respect to the General Partner Interest so transferred are assumed by the transferee and the transferee agrees to be bound by the provisions of this Agreement; provided, however, that in either such case, the transferee is primarily controlled, directly or indirectly, by the MLP or the MLP General Partner or any Person primarily controlling, directly or indirectly, the MLP or the MLP General Partner; provided, further, that in either such case, such transferee furnishes to the Partnership an Opinion of Counsel that such merger, consolidation, combination, transfer or assumption will not result in a loss of limited liability of any Limited Partner or cause the Partnership to be taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not already so treated or taxed). In the case of a transfer pursuant to this Section 4.2 to a Person proposed as a successor general partner of the Partnership, the transferee or successor (as the case may be) shall, subject to compliance with the terms of
Section 10.4, be admitted to the Partnership as the General Partner immediately prior to the transfer of the Partnership Interest, and the business of the Partnership shall continue without dissolution.

Section 4.3 Transfer of a Limited Partner's Partnership Interest. A Limited Partner may transfer all, but not less than all, of its Partnership Interest as a Limited Partner in connection with the merger, consolidation or other combination of such Limited Partner with or into any other Person or the transfer by such Limited Partner of all or substantially all of its assets to another Person and, following any such transfer, such Person may become a Substituted Limited Partner pursuant to Article X. Except as set forth in the immediately preceding sentence, or in connection with any pledge of (or any related foreclosure on) a Partnership Interest of a Limited Partner solely for the purpose of securing, directly or indirectly, indebtedness of the Partnership or the MLP, a Limited Partner may not transfer all or any part of its Partnership Interest or withdraw from the Partnership.

Section 4.4 Restrictions on Transfers.

(a) Notwithstanding the other provisions of this Article IV, no transfer of any Partnership Interest shall be made if such transfer would (i) violate the then applicable federal or state securities laws or the rules and regulations of the Commission, any state securities commission or any other governmental authority with jurisdiction over such transfer, (ii)

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terminate the existence or qualification of the Partnership or the MLP under the laws of the jurisdiction of its formation or (iii) cause the Partnership or the MLP to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not already so treated or taxed).

(b) The General Partner may impose restrictions on the transfer of Partnership Interests if a subsequent Opinion of Counsel determines that such restrictions are necessary to avoid a significant risk of the Partnership or the MLP becoming taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes. The restrictions may be imposed by making such amendments to this Agreement as the General Partner may determine to be necessary or appropriate to impose such restrictions.

ARTICLE V

CAPITAL CONTRIBUTIONS AND ISSUANCE OF PARTNERSHIP INTERESTS

Section 5.1 Initial Contributions. In connection with the formation of the Partnership under the Delaware Act, the General Partner purchased a 0.10% General Partner Interest for $1.00 and was admitted as General Partner, and Penn Octane Corporation purchased a 99.9% Limited Partner Interest in the Partnership for $999.00 and was admitted as a Limited Partner.

Section 5.2 Contributions Pursuant to the Contribution Agreement.

(a) Pursuant to the Contribution Agreement, Penn Octane Corporation shall contribute to the Partnership all of its right, title and interest in the Assets as a Capital Contribution.

(b) Penn Octane Corporation then, pursuant to the Contribution Agreement, shall contribute its 99.9% Limited Partner Interest in the Partnership to the MLP as a capital contribution.

(c) Following the foregoing transactions, the General Partner will continue to own a 0.10% General Partner Interest, the MLP will own a 99.9% Limited Partner Interest and shall be admitted as a Limited Partner and Penn Octane Corporation shall no longer own any Partnership Interest and shall withdraw as a Limited Partner.

Section 5.3 Additional Capital Contributions. With the consent of the General Partner, any Limited Partner may, but shall not be obligated to, make additional Capital Contributions to the Partnership. Contemporaneously with the making of any Capital Contributions by a Limited Partner, in addition to those provided in Sections 5.1 and 5.2, the General Partner shall be obligated to make an additional Capital Contribution to the Partnership in an amount equal to 0.10 divided by 99.9 times the amount of the additional Capital Contribution then made by such Limited Partner. Except as set forth in the immediately preceding sentence and in Article XII, the General Partner shall not be obligated to make any additional Capital Contributions to the Partnership.

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Section 5.4 Interest and Withdrawal. No interest shall be paid by the Partnership on Capital Contributions. No Partner or Assignee shall be entitled to the withdrawal or return of its Capital Contribution, except to the extent, if any, that distributions made pursuant to this Agreement or upon termination of the Partnership may be considered as such by law and then only to the extent provided for in this Agreement. Except to the extent expressly provided in this Agreement, no Partner or Assignee shall have priority over any other Partner or Assignee either as to the return of Capital Contributions or as to profits, losses or distributions. Any such return shall be a compromise to which all Partners and Assignees agree within the meaning of Section 17-502(b) of the Delaware Act.

Section 5.5 Capital Accounts.

(a) The Partnership shall maintain for each Partner (or a beneficial owner of Partnership Interests held by a nominee in any case in which the nominee has furnished the identity of such owner to the Partnership in accordance with Section 6031(c) of the Code or any other method acceptable to the General Partner in its sole discretion) owning a Partnership Interest a separate Capital Account with respect to such Partnership Interest in accordance with the rules of Treasury Regulation Section 1.704-1(b)(2)(iv). Such Capital Account shall be increased by (i) the amount of all Capital Contributions made to the Partnership with respect to such Partnership Interest pursuant to this Agreement and (ii) all items of Partnership income and gain (including, without limitation, income and gain exempt from tax) computed in accordance with Section 5.5(b) and allocated with respect to such Partnership Interest pursuant to Section 6.1, and decreased by (x) the amount of cash or Net Agreed Value of all actual and deemed distributions of cash or property made with respect to such Partnership Interest pursuant to this Agreement and (y) all items of Partnership deduction and loss computed in accordance with Section 5.5(b) and allocated with respect to such Partnership Interest pursuant to Section 6.1.

(b) For purposes of computing the amount of any item of income, gain, loss or deduction that is to be allocated pursuant to Article VI and is to be reflected in the Partners' Capital Accounts, the determination, recognition and classification of any such item shall be the same as its determination, recognition and classification for federal income tax purposes (including, without limitation, any method of depreciation, cost recovery or amortization used for that purpose), provided, that:

(i) Solely for purposes of this Section 5.5, the Partnership shall be treated as owning directly its proportionate share (as determined by the General Partner) of all property owned by any OLP Subsidiary that is classified as a partnership for federal income tax purposes.

(ii) All fees and other expenses incurred by the Partnership to promote the sale of (or to sell) a Partnership Interest that can neither be deducted nor amortized under Section 709 of the Code, if any, shall, for purposes of Capital Account maintenance, be treated as an item of deduction at the time such fees and other expenses are incurred and shall be allocated among the Partners pursuant to Section 6.1.

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(iii) Except as otherwise provided in Treasury Regulation
Section 1.704-1(b)(2)(iv)(m), computation of all items of income, gain, loss and deduction shall be made without regard to any election under Section 754 of the Code that may be made by the Partnership and, as to those items described in
Section 705(a)(1)(B) or 705(a)(2)(B) of the Code, without regard to the fact that such items are not includable in gross income or are neither currently deductible nor capitalized for federal income tax purposes. To the extent an adjustment to the adjusted tax basis of any Partnership asset pursuant to
Section 734(b) or 743(b) of the Code is required, pursuant to Treasury Regulation Section 1.704-1(b)(2)(iv)(m), to be taken into account in determining Capital Accounts, the amount of such adjustment in the Capital Accounts shall be treated as an item of gain or loss.

(iv) Any income, gain or loss attributable to the taxable disposition of any Partnership property shall be determined as if the adjusted basis of such property as of such date of disposition were equal in amount to the Partnership's Carrying Value with respect to such property as of such date.

(v) In accordance with the requirements of Section 704(b) of the Code, any deductions for depreciation, cost recovery or amortization attributable to any Contributed Property shall be determined as if the adjusted basis of such property on the date it was acquired by the Partnership were equal to the Agreed Value of such property. Upon an adjustment pursuant to Section 5.5(d) to the Carrying Value of any Partnership property subject to depreciation, cost recovery or amortization, any further deductions for such depreciation, cost recovery or amortization attributable to such property shall be determined (A) as if the adjusted basis of such property were equal to the Carrying Value of such property immediately following such adjustment and (B) using a rate of depreciation, cost recovery or amortization derived from the same method and useful life (or, if applicable, the remaining useful life) as is applied for federal income tax purposes; provided, however, that, if the asset has a zero adjusted basis for federal income tax purposes, depreciation, cost recovery or amortization deductions shall be determined using any reasonable method that the General Partner may adopt.

(vi) If the Partnership's adjusted basis in a depreciable or cost recovery property is reduced for federal income tax purposes pursuant to
Section 48(q)(1) or 48(q)(3) of the Code, the amount of such reduction shall, solely for purposes hereof, be deemed to be an additional depreciation or cost recovery deduction in the year such property is placed in service and shall be allocated among the Partners pursuant to Section 6.1. Any restoration of such basis pursuant to Section 48(q)(2) of the Code shall, to the extent possible, be allocated in the same manner to the Partners to whom such deemed deduction was allocated.

(c) A transferee of a Partnership Interest shall succeed to a pro rata portion of the Capital Account of the transferor relating to the Partnership Interest so transferred.

(d) (i) In accordance with Treasury Regulation Section 1.704-1(b)(2)(iv)(f), on an issuance of additional Partnership Interests for cash or Contributed Property, the Capital Accounts of all Partners and the Carrying Value of each Partnership property immediately prior to such issuance shall be adjusted upward or downward to reflect any Unrealized Gain or Unrealized Loss attributable to such Partnership property, as if such

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Unrealized Gain or Unrealized Loss had been recognized on an actual sale of each such property immediately prior to such issuance and had been allocated to the Partners at such time pursuant to Section 6.1 in the same manner as any item of gain or loss actually recognized during such period would have been allocated. In determining such Unrealized Gain or Unrealized Loss, the aggregate cash amount and fair market value of all Partnership assets (including, without limitation, cash or cash equivalents) immediately prior to the issuance of additional Partnership Interests shall be determined by the General Partner using such reasonable method of valuation as it may adopt; provided, however, that the General Partner, in arriving at such valuation, must take fully into account the fair market value of the Partnership Interests of all Partners at such time. The General Partner shall allocate such aggregate value among the assets of the Partnership (in such manner as it determines in its discretion to be reasonable) to arrive at a fair market value for individual properties.

(i) In accordance with Treasury Regulation Section 1.704-1(b)(2)(iv)(f), immediately prior to any actual or deemed distribution to a Partner of any Partnership property (other than a distribution of cash that is not in redemption or retirement of a Partnership Interest), the Capital Accounts of all Partners and the Carrying Value of all Partnership property shall be adjusted upward or downward to reflect any Unrealized Gain or Unrealized Loss attributable to such Partnership property, as if such Unrealized Gain or Unrealized Loss had been recognized in a sale of such property immediately prior to such distribution for an amount equal to its fair market value, and had been allocated to the Partners, at such time, pursuant to Section 6.1(c) in the same manner as any item of gain or loss actually recognized during such period would have been allocated. In determining such Unrealized Gain or Unrealized Loss the aggregate cash amount and fair market value of all Partnership assets (including, without limitation, cash or cash equivalents) immediately prior to a distribution shall (A) in the case of an actual distribution that is not made pursuant to Section 12.4 or in the case of a deemed distribution, be determined and allocated in the same manner as that provided in Section 5.5(d)(i) or (B) in the case of a liquidating distribution pursuant to Section 12.4, be determined and allocated by the Liquidator using such reasonable method of valuation as it may adopt.

Section 5.6 Loans from Partners. Loans by a Partner to the Partnership shall not constitute Capital Contributions. If any Partner shall advance funds to the Partnership in excess of the amounts required hereunder to be contributed by it to the capital of the Partnership, the making of such excess advances shall not result in any increase in the amount of the Capital Account of such Partner. The amount of any such excess advances shall be a debt obligation of the Partnership to such Partner and shall be payable or collectible only out of the Partnership assets in accordance with the terms and conditions upon which such advances are made.

Section 5.7 Issuances of Additional Partnership Securities.

(a) The Partnership may issue additional Partnership Securities and options, rights, warrants and appreciation rights relating to the Partnership Securities for any Partnership purpose at any time and from time to time to such Persons for such consideration and on such terms and conditions as shall be established by the General Partner in its sole discretion. The

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issuance by the Partnership of Partnership Securities or rights, warrants or appreciation rights in respect thereof shall be deemed an amendment to this Agreement.

(b) Each additional Partnership Security authorized to be issued by the Partnership pursuant to Section 5.7(a) may be issued in one or more classes, or one or more series of any such classes, with such designations, preferences, rights, powers and duties (which may be senior to existing classes and series of Partnership Securities), as shall be fixed by the General Partner in its sole discretion, including (i) the right to share Partnership profits and losses or items thereof; (ii) the right to share in Partnership distributions;
(iii) the rights upon dissolution and liquidation of the Partnership; (iv) whether, and the terms and conditions upon which, the Partnership may redeem such Partnership Security; (v) whether such Partnership Security is issued with the privilege of conversion or exchange and, if so, the terms and conditions of such conversion or exchange; (vi) the terms and conditions upon which each Partnership Security will be issued, evidenced by certificates and assigned or transferred; and (vii) the right, if any, of the holder of each such Partnership Security to vote on Partnership matters, including matters relating to the relative designations, preferences, rights, powers and duties of such Partnership Security.

(c) The General Partner is hereby authorized and directed to take all actions that it deems necessary or appropriate in connection with (i) each issuance of Partnership Securities and options, rights, warrants and appreciation rights relating to Partnership Securities pursuant to this Section 5.7, (ii) the admission of Additional Limited Partners and (iii) all additional

issuances of Partnership Securities. The General Partner is further authorized and directed to specify the relative rights, powers and duties of the holders of the Partnership Interests or other Partnership Securities being so issued. The General Partner shall do all things necessary to comply with the Delaware Act and is authorized and directed to do all things it deems necessary or advisable in connection with any future issuance of Partnership Securities, including compliance with any statute, rule, regulation or guideline of any federal, state or other governmental agency.

Section 5.8 Limited Preemptive Rights. Except as provided in Section 5.3, no Person shall have preemptive, preferential or other similar rights with

respect to (a) additional Capital Contributions; (b) issuance or sale of any class or series of Partnership Interests, whether unissued, held in the treasury or hereafter created; (c) issuance of any obligations, evidences of indebtedness or other securities of the Partnership convertible into or exchangeable for, or carrying or accompanied by any rights to receive, purchase or subscribe to, any such Partnership Interests; (d) issuance of any right of subscription to or right to receive, or any warrant or option for the purchase of, any such Partnership Interests; or (e) issuance or sale of any other securities that may be issued or sold by the Partnership.

Section 5.9 Fully Paid and Non-Assessable Nature of Limited Partner Interests. All Limited Partner Interests issued pursuant to, and in accordance with the requirements of, this Article V shall be fully paid and non-assessable Limited Partner Interests, except as such non-assessability may be affected by
Section 17-607 of the Delaware Act.

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ARTICLE VI

ALLOCATIONS AND DISTRIBUTIONS

Section 6.1 Allocations for Capital Account Purposes. For purposes of maintaining the Capital Accounts and in determining the rights of the Partners among themselves, the Partnership's items of income, gain, loss and deduction (computed in accordance with Section 5.5(b)) shall be allocated among the Partners in each taxable year (or portion thereof) as provided herein below.

(a) Net Income. After giving effect to the special allocations set forth in Section 6.1(d), Net Income for each taxable year and all items of income, gain, loss and deduction taken into account in computing Net Income for such taxable year shall be allocated among the Partners as follows:

(i) First, 100% to the General Partner, until the aggregate Net Income allocated to the General Partner pursuant to this Section 6.1(a)(i) for the current taxable year and all previous taxable years is equal to the aggregate Net Losses allocated to the General Partner pursuant to Section 6.1(b)(ii) for all previous taxable years;

(ii) Second, 0.10% to the General Partner and 99.9% to the Limited Partners in accordance with their respective Percentage Interests.

(b) Net Losses. After giving effect to the special allocations set forth in Section 6.1(d), Net Losses for each taxable period and all items of income, gain, loss and deduction taken into account in computing Net Losses for such taxable period shall be allocated among the Partners as follows:

(i) First, 0.10% to the General Partner and 99.9% to the Limited Partners, in accordance with their respective Percentage Interests; provided, however, that Net Losses shall not be allocated to a Limited Partner pursuant to this Section 6.1(b)(i) to the extent that such allocation would cause a Limited Partner to have a deficit balance in its Adjusted Capital Account at the end of such taxable year (or increase any existing deficit balance in such Limited Partner's Adjusted Capital Account);

(ii) Second, the balance, if any, 100% to the General Partner.

(c) Net Termination Gains and Losses. After giving effect to the special allocations set forth in Section 6.1(d), all items of income, gain, loss and deduction taken into account in computing Net Termination Gain or Net Termination Loss for such taxable period shall be allocated in the same manner as such Net Termination Gain or Net Termination Loss is allocated hereunder. All allocations under this Section 6.1(c) shall be made after Capital Account balances have been adjusted by all other allocations provided under this Section 6.1 and after all distributions of Available Cash provided under Section 6.4
have been made with respect to the taxable period ending on or before the Liquidation Date; provided, however, that solely for purposes of this Section 6.1(c), Capital Accounts shall not be adjusted for distributions made pursuant to Section 12.4.

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(i) If a Net Termination Gain is recognized (or deemed recognized pursuant to Section 5.5(d)), such Net Termination Gain shall be allocated among the Partners in the following manner (and the Capital Accounts of the Partners shall be increased by the amount so allocated in each of the following subclauses, in the order listed, before an allocation is made pursuant to the next succeeding subclause):

(A) First, to each Partner having a deficit balance in its Capital Account, in the proportion that such deficit balance bears to the total deficit balances in the Capital Accounts of all Partners, until each such Partner has been allocated Net Termination Gain equal to any such deficit balance in its Capital Account; and

(B) Second, 0.10% to the General Partner and 99.9% to the Limited Partners, in accordance with their respective Percentage Interests.

(ii) If a Net Termination Loss is recognized (or deemed recognized pursuant to Section 5.5(d)), such Net Termination Loss shall be allocated among the Partners in the following manner:

(A) First, to the General Partner and the Limited Partners in proportion to, and to the extent of, the positive balances in their respective Capital Accounts; and

(B) Second, the balance, if any, 100% to the General Partner.

(d) Special Allocations. Notwithstanding any other provision of this Section 6.1, the following special allocations shall be made for such taxable period:

(i) Partnership Minimum Gain Chargeback. Notwithstanding any other provision of this Section 6.1, if there is a net decrease in Partnership Minimum Gain during any Partnership taxable period, each Partner shall be allocated items of Partnership income and gain for such period (and, if necessary, subsequent periods) in the manner and amounts provided in Treasury Regulation Sections 1.704-2(f)(6), 1.704-2(g)(2) and 1.704-2(j)(2)(i), or any successor provision. For purposes of this Section 6.1(d), each Partner's Adjusted Capital Account balance shall be determined, and the allocation of income or gain required hereunder shall be effected, prior to the application of any other allocations pursuant to this Section 6.1(d) with respect to such taxable period (other than an allocation pursuant to Sections 6.1(d)(v) and 6.1(d)(vi)). This Section 6.1(d)(i) is intended to comply with the Partnership Minimum Gain chargeback requirement in Treasury Regulation Section 1.704-2(f) and shall be interpreted consistently therewith.

(ii) Chargeback of Partner Nonrecourse Debt Minimum Gain. Notwithstanding the other provisions of this Section 6.1 (other than Section 6.1(d)(i)), except as provided in Treasury Regulation Section 1.704-2(i)(4), if there is a net decrease in Partner Nonrecourse Debt Minimum Gain during any Partnership taxable period, any Partner with a share of Partner Nonrecourse Debt Minimum Gain at the beginning of such taxable period shall be allocated items of Partnership income and gain for such period (and, if necessary, subsequent periods) in the manner and amounts provided in Treasury Regulation Sections 1.704-2(i)(4) and 1.704-2(j)(2)(ii), or any successor provisions. For purposes of this Section 6.1(d), each Partner's

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Adjusted Capital Account balance shall be determined, and the allocation of income or gain required hereunder shall be effected, prior to the application of any other allocations pursuant to this Section 6.1(d), other than Section 6.1(d)(i) and other than an allocation pursuant to Sections 6.1(d)(v) and
6.1(d)(vi), with respect to such taxable period. This Section 6.1(d)(ii) is
intended to comply with the chargeback of items of income and gain requirement in Treasury Regulation Section 1.704-2(i)(4) and shall be interpreted consistently therewith.

(iii) Qualified Income Offset. In the event any Partner unexpectedly receives any adjustments, allocations or distributions described in Treasury Regulation Sections 1.704-1(b)(2)(ii)(d)(4), 1.704-1(b)(2)(ii)(d)(5), or 1.704-1(b)(2)(ii)(d)(6), items of Partnership income and gain shall be specially allocated to such Partner in an amount and manner sufficient to eliminate, to the extent required by the Treasury Regulations promulgated under
Section 704(b) of the Code, the deficit balance, if any, in its Adjusted Capital Account created by such adjustments, allocations or distributions as quickly as possible unless such deficit balance is otherwise eliminated pursuant to Section 6.1(d)(i) or (ii).

(iv) Gross Income Allocations. In the event any Partner has a deficit balance in its Capital Account at the end of any Partnership taxable period in excess of the sum of (A) the amount such Partner is required to restore pursuant to the provisions of this Agreement and (B) the amount such Partner is deemed obligated to restore pursuant to Treasury Regulation Sections 1.704-2(g) and 1.704-2(i)(5), such Partner shall be specially allocated items of Partnership gross income and gain in the amount of such excess as quickly as possible; provided, that an allocation pursuant to this Section 6.1(d)(iv) shall be made only if and to the extent that such Partner would have a deficit balance in its Capital Account as adjusted after all other allocations provided for in this Section 6.1 have been tentatively made as if this Section 6.1(d)(iv) were

      ------------                                       ------------------
not  in  this  Agreement.

(v) Nonrecourse Deductions. Nonrecourse Deductions for any taxable period shall be allocated to the Partners in accordance with their respective Percentage Interests. If the General Partner determines in its good faith discretion that the Partnership's Nonrecourse Deductions must be allocated in a different ratio to satisfy the safe harbor requirements of the Treasury Regulations promulgated under Section 704(b) of the Code, the General Partner is authorized, upon notice to the other Partners, to revise the prescribed ratio to the numerically closest ratio that does satisfy such requirements.

(vi) Partner Nonrecourse Deductions. Partner Nonrecourse Deductions for any taxable period shall be allocated 100% to the Partner that bears the Economic Risk of Loss with respect to the Partner Nonrecourse Debt to which such Partner Nonrecourse Deductions are attributable in accordance with Treasury Regulation Section 1.704-2(i). If more than one Partner bears the Economic Risk of Loss with respect to a Partner Nonrecourse Debt, such Partner Nonrecourse Deductions attributable thereto shall be allocated between or among such Partners in accordance with the ratios in which they share such Economic Risk of Loss.

(vii) Nonrecourse Liabilities. For purposes of Treasury Regulation Section 1.752-3(a)(3), the Partners agree that Nonrecourse Liabilities of the Partnership in excess of the sum of (A) the amount of Partnership Minimum Gain and (B) the total amount of

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Nonrecourse Built-in Gain shall be allocated among the Partners in accordance with their respective Percentage Interests.

(viii) Code Section 754 Adjustments. To the extent an adjustment to the adjusted tax basis of any Partnership asset pursuant to
Section 734(b) or 743(c) of the Code is required, pursuant to Treasury Regulation Section 1.704-1(b)(2)(iv)(m), to be taken into account in determining Capital Accounts, the amount of such adjustment to the Capital Accounts shall be treated as an item of gain (if the adjustment increases the basis of the asset) or loss (if the adjustment decreases such basis), and such item of gain or loss shall be specially allocated to the Partners in a manner consistent with the manner in which their Capital Accounts are required to be adjusted pursuant to such Section of the Treasury Regulations.

(ix) Curative Allocation.

(A) Notwithstanding any other provision of this Section 6.1, other than the Required Allocations, the Required Allocations shall be

taken into account in making the Agreed Allocations so that, to the extent possible, the net amount of items of income, gain, loss and deduction allocated to each Partner pursuant to the Required Allocations and the Agreed Allocations, together, shall be equal to the net amount of such items that would have been allocated to each such Partner under the Agreed Allocations had the Required Allocations and the related Curative Allocation not otherwise been provided in this Section 6.1. Notwithstanding the preceding sentence, Required Allocations relating to (1) Nonrecourse Deductions shall not be taken into account except to the extent that there has been a decrease in Partnership Minimum Gain and (2) Partner Nonrecourse Deductions shall not be taken into account except to the extent that there has been a decrease in Partner Nonrecourse Debt Minimum Gain. Allocations pursuant to this Section 6.1(d)(ix)(A) shall only be made with respect to Required Allocations to the extent the General Partner reasonably determines that such allocations will otherwise be inconsistent with the economic agreement among the Partners. Further, allocations pursuant to this
Section 6.1(d)(ix)(A) shall be deferred with respect to allocations pursuant to clauses (1) and (2) hereof to the extent the General Partner reasonably determines that such allocations are likely to be offset by subsequent Required Allocations.

(B) The General Partner shall have reasonable discretion, with respect to each taxable period, to (1) apply the provisions of
Section 6.1(d)(ix)(A) in whatever order is most likely to minimize the economic distortions that might otherwise result from the Required Allocations, and (2) divide all allocations pursuant to Section 6.1(d)(ix)(A) among the Partners in a manner that is likely to minimize such economic distortions.

Section 6.2 Allocations for Tax Purposes.

(a) Except as otherwise provided herein, for federal income tax purposes, each item of income, gain, loss and deduction shall be allocated among the Partners in the same manner as its correlative item of "book" income, gain, loss or deduction is allocated pursuant to Section 6.1.

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(b) In an attempt to eliminate Book-Tax Disparities attributable to a Contributed Property or Adjusted Property, items of income, gain, loss, depreciation, amortization and cost recovery deductions shall be allocated for federal income tax purposes among the Partners as follows:

(i) (A) In the case of a Contributed Property, such items attributable thereto shall be allocated among the Partners in the manner provided under Section 704(c) of the Code that takes into account the variation between the Agreed Value of such property and its adjusted basis at the time of contribution; and (B) any item of Residual Gain or Residual Loss attributable to a Contributed Property shall be allocated among the Partners in the same manner as its correlative item of "book" gain or loss is allocated pursuant to Section 6.1.

(ii) (A) In the case of an Adjusted Property, such items shall (1) first, be allocated among the Partners in a manner consistent with the principles of Section 704(c) of the Code to take into account the Unrealized Gain or Unrealized Loss attributable to such property and the allocations thereof pursuant to Section 5.5(d)(i) or 5.5(d)(ii), and (2) second, in the event such property was originally a Contributed Property, be allocated among the Partners in a manner consistent with Section 6.2(b)(i)(A); and (B) any item of Residual Gain or Residual Loss attributable to an Adjusted Property shall be allocated among the Partners in the same manner as its correlative item of "book" gain or loss is allocated pursuant to Section 6.1.

(iii) The General Partner shall apply the principles of Treasury Regulation Section 1.704-3(d) to eliminate Book-Tax Disparities.

(c) For the proper administration of the Partnership and for the preservation of uniformity of the Units or other limited partner interests of the MLP (or any class or classes thereof), the General Partner shall have sole discretion to (i) adopt such conventions as it deems appropriate in determining the amount of depreciation, amortization and cost recovery deductions; (ii) make special allocations for federal income tax purposes of income (including, without limitation, gross income) or deductions; and (iii) amend the provisions of this Agreement as appropriate (x) to reflect the proposal or promulgation of Treasury Regulations under Section 704(b) or Section 704(c) of the Code or (y) otherwise to preserve or achieve uniformity of the Units or other limited partner interests of the MLP (or any class or classes thereof). The General Partner may adopt such conventions, make such allocations and make such amendments to this Agreement as provided in this Section 6.2(c) only if such conventions, allocations or amendments would not have a material adverse effect on the Partners, the holders of any class or classes of Units or other limited partner interests of the MLP issued and outstanding or the Partnership, and if such allocations are consistent with the principles of Section 704 of the Code.

(d) The General Partner in its discretion may determine to depreciate or amortize the portion of an adjustment under Section 743(b) of the Code attributable to unrealized appreciation in any Adjusted Property (to the extent of the unamortized Book-Tax Disparity) using a predetermined rate derived from the depreciation or amortization method and useful life applied to the Partnership's common basis of such property, despite any inconsistency of such approach with Treasury Regulation Section 1.167(c)-l(a)(6) or any successor regulations thereto.

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If the General Partner determines that such reporting position cannot reasonably be taken, the General Partner may adopt depreciation and amortization conventions under which all purchasers acquiring limited partner interests of the MLP in the same month would receive depreciation and amortization deductions, based upon the same applicable rate as if they had purchased a direct interest in the Partnership's property. If the General Partner chooses not to utilize such aggregate method, the General Partner may use any other reasonable depreciation and amortization conventions to preserve the uniformity of the intrinsic tax characteristics of any limited partner interests of the MLP that would not have a material adverse effect on the Partners or the holders of any class or classes of limited partner interests of the MLP.

(e) Any gain allocated to the Partners upon the sale or other taxable disposition of any Partnership asset shall, to the extent possible, after taking into account other required allocations of gain pursuant to this
Section 6.2, be characterized as Recapture Income in the same proportions and to the same extent as such Partners (or their predecessors in interest) have been allocated any deductions directly or indirectly giving rise to the treatment of such gains as Recapture Income.

(f) All items of income, gain, loss, deduction and credit recognized by the Partnership for federal income tax purposes and allocated to the Partners in accordance with the provisions hereof shall be determined without regard to any election under Section 754 of the Code that may be made by the Partnership; provided, however, that such allocations, once made, shall be adjusted as necessary or appropriate to take into account those adjustments permitted or required by Sections 734 and 743 of the Code.

(g) The General Partner may adopt such methods of allocation of income, gain, loss or deduction between a transferor and a transferee of a Partnership Interest as it determines necessary or appropriate in its sole discretion, to the extent permitted or required by Section 706 of the Code and the regulations or rulings promulgated thereunder.

(h) Allocations that would otherwise be made to a Partner under the provisions of this Article VI shall instead be made to the beneficial owner of Partnership Interests held by a nominee in any case in which the nominee has furnished the identity of such owner to the Partnership in accordance with
Section 6031(c) of the Code or any other method acceptable to the General Partner in its sole discretion.

Section 6.3 Distributions.

(a) Within 45 days following the end of each Quarter, an amount equal to 100% of Available Cash with respect to such Quarter shall, subject to
Section 17-607 of the Delaware Act, be distributed in accordance with this Article VI by the Partnership to the Partners in accordance with their respective Percentage Interests. The immediately preceding sentence shall not require any distribution of cash if and to the extent such distribution would be prohibited by applicable law or by any loan agreement, security agreement, mortgage, debt instrument or other agreement or obligation to which the Partnership is a party or by which it is bound or its assets are subject. All distributions required to be made under this Agreement shall be made subject to
Section 17-607 of the Delaware Act.

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(b) In the event of the dissolution and liquidation of the Partnership, all receipts received during or after the Quarter in which the Liquidation Date occurs, other than from borrowings described in (a)(ii) of the definition of Available Cash, shall be applied and distributed solely in accordance with, and subject to the terms and conditions of, Section 12.4.

(c) The General Partner shall have the discretion to treat taxes paid by the Partnership on behalf of, or amounts withheld with respect to, all or less than all of the Partners, as a distribution of Available Cash to such Partners.

ARTICLE VII

MANAGEMENT AND OPERATION OF BUSINESS

Section 7.1 Management.

(a) The General Partner shall conduct, direct and manage all activities of the Partnership. Except as otherwise expressly provided in this Agreement, all management powers over the business and affairs of the Partnership shall be exclusively vested in the General Partner, and no Limited Partner or Assignee shall have any management power over the business and affairs of the Partnership. In addition to the powers now or hereafter granted a general partner of a limited partnership under applicable law or that are granted to the General Partner under any other provision of this Agreement, the General Partner, subject to Section 7.3, shall have full power and authority to do all things and on such terms as it, in its sole discretion, may deem necessary or appropriate to conduct the business of the Partnership, to exercise all powers set forth in Section 2.5 and to effectuate the purposes set forth in Section 2.4, including the following:

(i) the making of any expenditures, the lending or borrowing of money, the assumption or guarantee of, or other contracting for, indebtedness and other liabilities, the issuance of evidences of indebtedness, including indebtedness that is convertible into a Partnership Interest, and the incurring of any other obligations;

(ii) the making of tax, regulatory and other filings, or rendering of periodic or other reports to governmental or other agencies having jurisdiction over the business or assets of the Partnership;

(iii) the acquisition, disposition, mortgage, pledge, encumbrance, hypothecation or exchange of any or all of the assets of the Partnership or the merger or other combination of the Partnership with or into another Person (the matters described in this clause (iii) being subject, however, to any prior approval that may be required by Section 7.3);

(iv) the use of the assets of the Partnership (including cash on hand) for any purpose consistent with the terms of this Agreement, including the financing of the conduct of the operations of the Partnership Group; subject to Section 7.6, the lending of funds to other Persons (including the MLP and any member of the Partnership Group); the repayment of obligations of the MLP or any member of the Partnership Group and the making of capital contributions to any member of the Partnership Group;

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(v) the negotiation, execution and performance of any contracts, conveyances or other instruments (including instruments that limit the liability of the Partnership under contractual arrangements to all or particular assets of the Partnership, with the other party to the contract to have no recourse against the General Partner or its assets other than its interest in the Partnership, even if same results in the terms of the transaction being less favorable to the Partnership than would otherwise be the case);

(vi) the distribution of Partnership cash;

(vii) the selection and dismissal of employees (including employees having titles such as "president," "vice president," "secretary" and "treasurer") and agents, outside attorneys, accountants, consultants and contractors and the determination of their compensation and other terms of employment or hiring;

(viii) the maintenance of such insurance for the benefit of the Partnership Group and the Partners as it deems necessary or appropriate;

(ix) the formation of, or acquisition of an interest in, and the contribution of property and the making of loans to, any further limited or general partnerships, joint ventures, corporations, limited liability companies or other relationships subject to the restrictions set forth in Section 2.4;

(x) the control of any matters affecting the rights and obligations of the Partnership, including the bringing and defending of actions at law or in equity and otherwise engaging in the conduct of litigation and the incurring of legal expense and the settlement of claims and litigation; and

(xi) the indemnification of any Person against liabilities and contingencies to the extent permitted by law.

(b) Notwithstanding any other provision of this Agreement, the MLP Agreement, the Delaware Act or any applicable law, rule or regulation, each of the Partners and the Assignees and each other Person who may acquire an interest in the Partnership hereby (i) approves, ratifies and confirms the execution, delivery and performance by the parties thereto of this Agreement, the Omnibus Agreement, the Contribution Agreement and the other agreements and documents described in or filed as exhibits to the Registration Statement that are related to the transactions contemplated by the Registration Statement; (ii) agrees that the General Partner (on its own or through any officer of the Partnership) is authorized to execute, deliver and perform the agreements referred to in clause
(i) of this sentence, as applicable, and the other agreements, acts, transactions and matters described in or contemplated by the Registration Statement on behalf of the Partnership without any further act, approval or vote of the Partners or the Assignees or the other Persons who may acquire an interest in the Partnership; and (iii) agrees that the execution, delivery or performance by the General Partner, the MLP, any Group Member or any Affiliate of any of them, of this Agreement or any agreement authorized or permitted under this Agreement (including the exercise by the General Partner or any Affiliate of the General Partner of the rights accorded pursuant to Article XV), shall not constitute a breach

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by the General Partner of any duty that the General Partner may owe the Partnership or the Limited Partners or any other Persons under this Agreement (or any other agreements) or of any duty stated or implied by law or equity.

Section 7.2 Certificate of Limited Partnership. The General Partner has caused the Certificate of Limited Partnership to be filed with the Secretary of State of the State of Delaware as required by the Delaware Act. The General Partner shall use all reasonable efforts to cause to be filed such other certificates or documents as may be determined by the General Partner in its sole discretion to be reasonable and necessary or appropriate for the formation, continuation, qualification and operation of a limited partnership (or a partnership in which the limited partners have limited liability) in the State of Delaware or any other state in which the Partnership may elect to do business or own property. To the extent that such action is determined by the General Partner in its sole discretion to be reasonable and necessary or appropriate, the General Partner shall file amendments to and restatements of the Certificate of Limited Partnership and do all things to maintain the Partnership as a limited partnership (or a partnership or other entity in which the limited partners have limited liability) under the laws of the State of Delaware or of any other state in which the Partnership may elect to do business or own property. Subject to the terms of Section 3.4(a), the General Partner shall not be required, before or after filing, to deliver or mail a copy of the Certificate of Limited Partnership, any qualification document or any amendment thereto to any Limited Partner or Assignee.

Section 7.3 Restrictions on the General Partner's Authority.

(a) The General Partner may not, without written approval of the specific act by the Limited Partners or by other written instrument executed and delivered by the Limited Partners subsequent to the date of this Agreement, take any action in contravention of this Agreement, including, except as otherwise provided in this Agreement, (i) committing any act that would make it impossible to carry on the ordinary business of the Partnership; (ii) possessing Partnership property, or assigning any rights in specific Partnership property, for other than a Partnership purpose; (iii) admitting a Person as a Partner;
(iv) amending this Agreement in any manner; or (v) transferring its General Partner Interest.

(b) Except as provided in Articles XII and XIV, the General Partner may not sell, exchange or otherwise dispose of all or substantially all of the Partnership's assets in a single transaction or a series of related transactions (including by way of merger, consolidation or other combination) or approve on behalf of the Partnership the sale, exchange or other disposition of all or substantially all of the assets of the Partnership, without the approval of the Limited Partners; provided however that this provision shall not preclude or limit the General Partner's ability to mortgage, pledge, hypothecate or grant a security interest in all or substantially all of the assets of the Partnership and shall not apply to any forced sale of any or all of the assets of the Partnership pursuant to the foreclosure of, or other realization upon, any such encumbrance.

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Section 7.4 Reimbursement of the General Partner.

(a) Except as provided in this Section 7.4 and elsewhere in this Agreement or in the Omnibus Agreement, the General Partner shall not be compensated for its services as General Partner or as general partner or managing member of any Group Member.

(b) The General Partner shall be reimbursed on a monthly basis, or such other reasonable basis as the General Partner may determine in its sole discretion, for (i) all direct and indirect expenses it incurs or payments it makes on behalf of the Partnership (including salary, bonus, incentive compensation and other amounts paid to any Person including Affiliates of the General Partner to perform services for the Partnership or for the General Partner in the discharge of its duties to the Partnership), and (ii) all other necessary or appropriate expenses allocable to the Partnership or otherwise reasonably incurred by the General Partner in connection with operating the Partnership's business (including expenses allocated to the General Partner by its Affiliates). The General Partner shall determine the expenses that are allocable to the Partnership in any reasonable manner determined by the General Partner in its sole discretion. Reimbursements pursuant to this Section 7.4 shall be in addition to any reimbursement to the General Partner as a result of indemnification pursuant to Section 7.7.

(c) Subject to Section 5.7, the General Partner, in its sole discretion and without the approval of the Limited Partners (who shall have no right to vote in respect thereof), may propose and adopt on behalf of the Partnership employee benefit plans, employee programs and employee practices, or cause the Partnership to issue Partnership Interests in connection with or pursuant to any employee benefit plan, employee program or employee practice maintained or sponsored by the General Partner or any of its Affiliates, in each case for the benefit of employees of the General Partner, any Group Member or any Affiliate, or any of them, in respect of services performed, directly or indirectly, for the benefit of the Partnership Group. Expenses incurred by the General Partner in connection with any such plans, programs and practices shall be reimbursed in accordance with Section 7.4(b). Any and all obligations of the General Partner under any employee benefit plans, employee programs or employee practices adopted by the General Partner as permitted by this Section 7.4(c) shall constitute obligations of the General Partner hereunder and shall be assumed by any successor General Partner approved pursuant to Section 11.1 or 11.2 or the transferee of or successor to all of the General Partner's General

Partner Interest pursuant to Section 4.2.

Section 7.5 Outside Activities.

(a) After the Closing Date, the General Partner, for so long as it is the General Partner of the Partnership, (i) agrees that its sole business will be to act as the General Partner of the Partnership and a general partner or managing member, as the case may be, of any other partnership or limited liability company of which the Partnership is, directly or indirectly, a partner or member, and to undertake activities that are ancillary or related thereto, and (ii) shall not engage in any business or activity or incur any debts or liabilities except in connection with or incidental to (A) its performance as general partner of the Partnership or one or more Group Members or as described in or contemplated by the Registration Statement or (B) the acquiring, owning or disposing of debt or equity securities in any Group Member.

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(b) Except as specifically restricted by Section 7.5(a) and the Omnibus Agreement, each Indemnitee (other than the General Partner) shall have the right to engage in businesses of every type and description and other activities for profit and to engage in and possess an interest in other business ventures of any and every type or description, whether in businesses engaged in or anticipated to be engaged in by the MLP or any Group Member, independently or with others, including business interests and activities in direct competition with the business and activities of the MLP or any Group Member, and none of the same shall constitute a breach of this Agreement or any duty express or implied by law to the MLP or any Group Member or any Partner or Assignee. Neither the MLP nor any Group Member, any Limited Partner nor any other Person shall have any rights by virtue of this Agreement, the MLP Agreement or the partnership relationship established hereby or thereby in any business ventures of any Indemnitee.

(c) Subject to the terms of Section 7.5(a), Section 7.5(b) and the Omnibus Agreement, but otherwise notwithstanding anything to the contrary in this Agreement, (i) the engaging in competitive activities by any Indemnitee (other than the General Partner) in accordance with the provisions of this
Section 7.5 is hereby approved by the Partnership and all Partners, (ii) it shall be deemed not to be a breach of the General Partner's fiduciary duty or any other obligation of any type whatsoever of the General Partner for the Indemnitees (other than the General Partner) to engage in such business interests and activities in preference to or to the exclusion of the Partnership and (iii) except as set forth in the Omnibus Agreement, the Indemnitees shall have no obligation to present business opportunities to the Partnership.

(d) The General Partner and any of its Affiliates may acquire Units or other MLP Securities in addition to those acquired on the Closing Date and, except as otherwise provided in this Agreement, shall be entitled to exercise all rights relating to such Units or MLP Securities.

(e) The term "Affiliates" when used in Section 7.5(a) and Section 7.5(d) with respect to the General Partner shall not include any Group Member or any Subsidiary of the MLP or any Group Member.

(f) Anything in this Agreement to the contrary notwithstanding, to the extent that provisions of Sections 7.7, 7.8, 7.9, 7.10 or other Sections of this Agreement purport or are interpreted to have the effect of restricting the fiduciary duties that might otherwise, as a result of Delaware or other applicable law, be owed by the General Partner to the Partnership and its Limited Partners, or to constitute a waiver or consent by the Limited Partners to any such restriction, such provisions shall be inapplicable and have no effect in determining whether the General Partner has complied with its fiduciary duties in connection with determinations made by it under this Section 7.5.

Section 7.6 Loans from the General Partner; Loans or Contributions from the Partnership; Contracts with Affiliates; Certain Restrictions on the General
Partner.

(a) The General Partner or any of its Affiliates may lend to the Partnership, the MLP or any Group Member, and the Partnership, the MLP or any Group Member may

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borrow from the General Partner or any of its Affiliates, funds needed or desired by the MLP or the Group Member for such periods of time and in such amounts as the General Partner may determine; provided, however, that in any such case the lending party may not charge the borrowing party interest at a rate greater than the rate that would be charged the borrowing party or impose terms less favorable to the borrowing party than would be charged or imposed on the borrowing party by unrelated lenders on comparable loans made on an arm's-length basis (without reference to the lending party's financial abilities or guarantees). The borrowing party shall reimburse the lending party for any costs (other than any additional interest costs) incurred by the lending party in connection with the borrowing of such funds. For purposes of this Section 7.6(a) and Section 7.6(b), the term "Group Member" shall include any Affiliate of a Group Member that is controlled by the Group Member.

(b) The Partnership may lend or contribute to any Group Member, and any Group Member may borrow from the Partnership, funds on terms and conditions established in the sole discretion of the General Partner; provided, however, that the Partnership may not charge the Group Member interest at a rate less than the rate that would be charged to the Group Member (without reference to the General Partner's financial abilities or guarantees) by unrelated lenders on comparable loans. The foregoing authority shall be exercised by the General Partner in its sole discretion and shall not create any right or benefit in favor of any Group Member or any other Person.

(c) The General Partner may itself, or may enter into an agreement with the MLP General Partner or any of its Affiliates to, render services to a Group Member or to the General Partner in the discharge of its duties as general partner of the Partnership. Any services rendered to a Group Member by the General Partner, the MLP General Partner or any of their Affiliates shall be on terms that are fair and reasonable to the Partnership; provided, however, that the requirements of this Section 7.6(c) shall be deemed satisfied as to (i) any transaction approved by Special Approval, (ii) any transaction, the terms of which are no less favorable to the Partnership Group than those generally being provided to or available from unrelated third parties or (iii) any transaction that, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to the Partnership Group), is equitable to the Partnership Group. The provisions of Section 7.4 shall apply to the rendering of services described in this Section 7.6(c).

(d) The Partnership Group may transfer assets to joint ventures, other partnerships, corporations, limited liability companies or other business entities in which it is or thereby becomes a participant upon such terms and subject to such conditions as are consistent with this Agreement and applicable law.

(e) Neither the General Partner nor any of its Affiliates shall sell, transfer or convey any property to, or purchase any property from, the Partnership, directly or indirectly, except pursuant to transactions that are fair and reasonable to the Partnership; provided, however, that the requirements of this Section 7.6(e) shall be deemed to be satisfied as to (i) the transactions effected pursuant to Sections 5.2 and 5.3, the Contribution Agreement and any other transactions described in or contemplated by the Registration Statement, (ii) any transaction approved by Special Approval, (iii) any transaction, the terms of which are no less favorable to

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the Partnership than those generally being provided to or available from unrelated third parties, or (iv) any transaction that, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to the Partnership Group), is equitable to the Partnership.

(f) The General Partner and its Affiliates will have no obligation to permit any Group Member to use any facilities or assets of the General Partner and its Affiliates, except as may be provided in contracts entered into from time to time specifically dealing with such use, nor shall there be any obligation on the part of the General Partner or its Affiliates to enter into such contracts.

(g) Without limitation of Sections 7.6(a) through 7.6(f), and notwithstanding anything to the contrary in this Agreement, the existence of the conflicts of interest described in the Registration Statement are hereby approved by all Partners.

Section 7.7 Indemnification.

(a) To the fullest extent permitted by law but subject to the limitations expressly provided in this Agreement, all Indemnitees shall be indemnified and held harmless by the Partnership from and against any and all losses, claims, damages, liabilities, joint or several, expenses (including legal fees and expenses), judgments, fines, penalties, interest, settlements or other amounts arising from any and all claims, demands, actions, suits or proceedings, whether civil, criminal, administrative or investigative, in which any Indemnitee may be involved, or is threatened to be involved, as a party or otherwise, by reason of its status as an Indemnitee; provided, that in each case the Indemnitee acted in good faith and in a manner that such Indemnitee reasonably believed to be in, or (in the case of a Person other than the General Partner) not opposed to, the best interests of the Partnership and, with respect to any criminal proceeding, had no reasonable cause to believe its conduct was unlawful; provided, further, no indemnification pursuant to this Section 7.7 shall be available to the General Partner with respect to its obligations incurred pursuant to the Underwriting Agreement or the Contribution Agreement (other than obligations incurred by the General Partner on behalf of the Partnership). The termination of any action, suit or proceeding by judgment, order, settlement, conviction or upon a plea of nolo contendere, or its equivalent, shall not create a presumption that the Indemnitee acted in a manner contrary to that specified above. Any indemnification pursuant to this Section 7.7 shall be made only out of the assets of the Partnership, it being agreed

that the General Partner shall not be personally liable for such indemnification and shall have no obligation to contribute or loan any monies or property to the Partnership to enable it to effectuate such indemnification.

(b) To the fullest extent permitted by law, expenses (including legal fees and expenses) incurred by an Indemnitee who is indemnified pursuant to Section 7.7(a) in defending any claim, demand, action, suit or proceeding shall, from time to time, be advanced by the Partnership prior to the final disposition of such claim, demand, action, suit or proceeding upon receipt by the Partnership of any undertaking by or on behalf of the Indemnitee to repay such amount if it shall be determined that the Indemnitee is not entitled to be indemnified as authorized in this Section 7.7.

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(c) The indemnification provided by this Section 7.7 shall be in addition to any other rights to which an Indemnitee may be entitled under any agreement, pursuant to any vote of the Partners, as a matter of law or otherwise, both as to actions in the Indemnitee's capacity as an Indemnitee and as to actions in any other capacity (including any capacity under the Underwriting Agreement), and shall continue as to an Indemnitee who has ceased to serve in such capacity and shall inure to the benefit of the heirs, successors, assigns and administrators of the Indemnitee.

(d) The Partnership may purchase and maintain (or reimburse the General Partner or its Affiliates for the cost of) insurance, on behalf of the General Partner, its Affiliates and such other Persons as the General Partner shall determine, against any liability that may be asserted against or expense that may be incurred by such Person in connection with the Partnership's activities or such Person's activities on behalf of the Partnership, regardless of whether the Partnership would have the power to indemnify such Person against such liability under the provisions of this Agreement.

(e) For purposes of this Section 7.7, the Partnership shall be deemed to have requested an Indemnitee to serve as fiduciary of an employee benefit plan whenever the performance by it of its duties to the Partnership also imposes duties on, or otherwise involves services by, it to the plan or participants or beneficiaries of the plan; excise taxes assessed on an Indemnitee with respect to an employee benefit plan pursuant to applicable law shall constitute "fines" within the meaning of Section 7.7(a); and action taken or omitted by it with respect to any employee benefit plan in the performance of its duties for a purpose reasonably believed by it to be in the interest of the participants and beneficiaries of the plan shall be deemed to be for a purpose that is in, or not opposed to, the best interests of the Partnership.

(f) In no event may an Indemnitee subject the Limited Partners to personal liability by reason of the indemnification provisions set forth in this Agreement.

(g) An Indemnitee shall not be denied indemnification in whole or in part under this Section 7.7 because the Indemnitee had an interest in the transaction with respect to which the indemnification applies if the transaction was otherwise permitted by the terms of this Agreement.

(h) The provisions of this Section 7.7 are for the benefit of the Indemnitees, their heirs, successors, assigns and administrators and shall not be deemed to create any rights for the benefit of any other Persons.

(i) No amendment, modification or repeal of this Section 7.7 or any provision hereof shall in any manner terminate, reduce or impair the right of any past, present or future Indemnitee to be indemnified by the Partnership, nor the obligations of the Partnership to indemnify any such Indemnitee under and in accordance with the provisions of this Section 7.7 as in effect immediately prior to such amendment, modification or repeal with respect to claims arising from or relating to matters occurring, in whole or in part, prior to such amendment, modification or repeal, regardless of when such claims may arise or be asserted.

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Section 7.8 Liability of Indemnitees.

(a) Notwithstanding anything to the contrary set forth in this Agreement, no Indemnitee shall be liable for monetary damages to the Partnership, the Limited Partners, the Assignees or any other Persons who have acquired interests in the Units or other MLP Securities, for losses sustained or liabilities incurred as a result of any act or omission if such Indemnitee acted in good faith.

(b) Subject to its obligations and duties as General Partner set forth in Section 7.1(a), the General Partner may exercise any of the powers granted to it by this Agreement and perform any of the duties imposed upon it hereunder either directly or by or through its agents, and the General Partner shall not be responsible for any misconduct or negligence on the part of any such agent appointed by the General Partner in good faith.

(c) To the extent that, at law or in equity, an Indemnitee has duties (including fiduciary duties) and liabilities relating thereto to the Partnership or to the Partners, the General Partner and any other Indemnitee acting in connection with the Partnership's business or affairs shall not be liable to the Partnership or to any Partner for its good faith reliance on the provisions of this Agreement. The provisions of this Agreement, to the extent that they restrict or otherwise modify the duties and liabilities of an Indemnitee otherwise existing at law or in equity, are agreed by the Partners to replace such other duties and liabilities of such Indemnitee.

(d) Any amendment, modification or repeal of this Section 7.8 or any provision hereof shall be prospective only and shall not in any way affect the limitations on the liability to the Partnership, the Limited Partners, the General Partner, and the Partnership's and General Partner's directors, officers and employees under this Section 7.8 as in effect immediately prior to such amendment, modification or repeal with respect to claims arising from or relating to matters occurring, in whole or in part, prior to such amendment, modification or repeal, regardless of when such claims may arise or be asserted.

Section 7.9 Resolution of Conflicts of Interest.

(a) Unless otherwise expressly provided in this Agreement or the MLP Agreement, whenever a potential conflict of interest exists or arises between the General Partner or any of its Affiliates, on the one hand, and the Partnership, the MLP, any Partner or any Assignee, on the other, any resolution or course of action by the General Partner or its Affiliates in respect of such conflict of interest shall be permitted and deemed approved by all Partners, and shall not constitute a breach of this Agreement, of the MLP Agreement, of any agreement contemplated herein or therein, or of any duty stated or implied by law or equity, if the resolution or course of action is, or by operation of this Agreement is deemed to be, fair and reasonable to the Partnership. The General Partner shall be authorized but not required in connection with its resolution of such conflict of interest to seek Special Approval of such resolution and the General Partner may also adopt a resolution or course of action that has not received Special Approval. Any Special Approval shall be subject to the presumption that, in making its decision, the Conflicts Committee acted on an informed basis, in good faith and in the honest belief that the action taken was in the best interests of the Partnership and the MLP and, in any proceeding

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brought by any Limited Partner or by or on behalf of such Limited Partner or any other Limited Partners or the Partnership challenging such approval, the Person bringing or prosecuting such proceeding shall have the burden of overcoming such presumption. Any conflict of interest and any resolution of such conflict of interest shall be conclusively deemed fair and reasonable to the Partnership if such conflict of interest or resolution is (i) approved by Special Approval,
(ii) on terms no less favorable to the Partnership than those generally being provided to or available from unrelated third parties or (iii) fair to the Partnership, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to the Partnership). The General Partner may also adopt a resolution or course of action that has not received Special Approval. The General Partner shall be authorized in connection with its determination of what is "fair and reasonable" to the Partnership and in connection with its resolution of any conflict of interest to consider (A) the relative interests of any party to such conflict, agreement, transaction or situation and the benefits and burdens relating to such interest; (B) any customary or accepted industry practices and any customary or historical dealings with a particular Person; (C) any applicable generally accepted accounting practices or principles; and (D) such additional factors as the General Partner determines in its sole discretion to be relevant, reasonable or appropriate under the circumstances. In any proceeding brought by any Limited Partner or by or on behalf of such Limited Partner or any other Limited Partners or the Partnership alleging that such a resolution by the General Partner is not fair to the Partnership, such Limited Partner shall have the burden of proof of overcoming such conclusion. Nothing contained in this Agreement, however, is intended to nor shall it be construed to require the General Partner to consider the interests of any Person other than the Partnership. In the absence of bad faith by the General Partner, the resolution, action or terms so made, taken or provided by the General Partner with respect to such matter shall not constitute a breach of this Agreement or any other agreement contemplated herein or a breach of any standard of care or duty imposed herein or therein or, to the extent permitted by law, under the Delaware Act or any other law, rule or regulation.

(b) Whenever this Agreement or any other agreement contemplated hereby provides that the General Partner or any of its Affiliates is permitted or required to make a decision (i) in its "sole discretion" or "discretion," that it deems "necessary or appropriate" or "necessary or advisable" or under a grant of similar authority or latitude, except as otherwise provided herein, the General Partner or such Affiliate shall be entitled to consider only such interests and factors as it desires and shall have no duty or obligation to give any consideration to any interest of, or factors affecting, the Partnership, the MLP, any Limited Partner or any Assignee, (ii) it may make such decision in its sole discretion (regardless of whether there is a reference to "sole discretion" or "discretion") unless another express standard is provided for, or (iii) in "good faith" or under another express standard, the General Partner or such Affiliate shall act under such express standard and shall not be subject to any other or different standards imposed by this Agreement, the MLP Agreement, any other agreement contemplated hereby or under the Delaware Act or any other law, rule or regulation. In addition, any actions taken by the General Partner or such Affiliate consistent with the standards of "reasonable discretion" set forth in the definition of Available Cash shall not constitute a breach of any duty of the General Partner to the Partnership or the Limited Partners. The General Partner shall have no duty, express or implied, to sell or otherwise dispose of any asset of the Partnership Group other than in the ordinary course of business. No borrowing by any Group Member or the approval thereof

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by the General Partner shall be deemed to constitute a breach of any duty of the General Partner to the Partnership or the Limited Partners by reason of the fact that the purpose or effect of such borrowing is directly or indirectly to (A) enable distributions to the General Partner or its Affiliates to exceed 0.10% of the total amount distributed to all Partners or (B) hasten the expiration of the Subordination Period or the conversion of any Subordinated Units into Common Units.

(c) Whenever a particular transaction, arrangement or resolution of a conflict of interest is required under this Agreement to be "fair and reasonable" to any Person, the fair and reasonable nature of such transaction, arrangement or resolution shall be considered in the context of all similar or related transactions.

(d) The Limited Partner hereby authorizes the General Partner, on behalf of the Partnership as a partner or member of a Group Member, to approve of actions by the general partner or managing member of such Group Member similar to those actions permitted to be taken by the General Partner pursuant to this Section 7.9.

Section 7.10 Other Matters Concerning the General Partner.

(a) The General Partner may rely and shall be protected in acting or refraining from acting upon any resolution, certificate, statement, instrument, opinion, report, notice, request, consent, order, bond, debenture or other paper or document believed by it to be genuine and to have been signed or presented by the proper party or parties.

(b) The General Partner may consult with legal counsel, accountants, appraisers, management consultants, investment bankers and other consultants and advisers selected by it, and any act taken or omitted to be taken in reliance upon the opinion (including an Opinion of Counsel) of such Persons as to matters that the General Partner reasonably believes to be within such Person's professional or expert competence shall be conclusively presumed to have been done or omitted in good faith and in accordance with such opinion.

(c) The General Partner shall have the right, in respect of any of its powers or obligations hereunder, to act through any of its duly authorized officers, a duly appointed attorney or attorneys-in-fact or the duly authorized officers of the Partnership.

(d) Any standard of care and duty imposed by this Agreement or under the Delaware Act or any applicable law, rule or regulation shall be modified, waived or limited, to the extent permitted by law, as required to permit the General Partner to act under this Agreement or any other agreement contemplated by this Agreement and to make any decision pursuant to the authority prescribed in this Agreement, so long as such action is reasonably believed by the General Partner to be in, or not inconsistent with, the best interests of the Partnership.

Section 7.11 Reliance by Third Parties. Notwithstanding anything to the contrary in this Agreement, any Person dealing with the Partnership shall be entitled to assume that the General Partner and any officer of the General Partner authorized by the General Partner to act on behalf of and in the name of the Partnership has full power and authority to encumber, sell or

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otherwise use in any manner any and all assets of the Partnership and to enter into any authorized contracts on behalf of the Partnership, and such Person shall be entitled to deal with the General Partner or any such officer as if it were the Partnership's sole party in interest, both legally and beneficially. Each Limited Partner hereby waives any and all defenses or other remedies that may be available against such Person to contest, negate or disaffirm any action of the General Partner or any such officer in connection with any such dealing. In no event shall any Person dealing with the General Partner or any such officer or its representatives be obligated to ascertain that the terms of the Agreement have been complied with or to inquire into the necessity or expedience of any act or action of the General Partner or any such officer or its representatives. Each and every certificate, document or other instrument executed on behalf of the Partnership by the General Partner or its representatives shall be conclusive evidence in favor of any and every Person relying thereon or claiming thereunder that (a) at the time of the execution and delivery of such certificate, document or instrument, this Agreement was in full force and effect, (b) the Person executing and delivering such certificate, document or instrument was duly authorized and empowered to do so for and on behalf of the Partnership and (c) such certificate, document or instrument was duly executed and delivered in accordance with the terms and provisions of this Agreement and is binding upon the Partnership.

ARTICLE VIII

BOOKS, RECORDS AND ACCOUNTING

Section 8.1 Records and Accounting. The General Partner shall keep or cause to be kept at the principal office of the Partnership appropriate books and records with respect to the Partnership's business, including all books and records necessary to provide to the Limited Partners any information required to be provided pursuant to Section 3.4(a). Any books and records maintained by or on behalf of the Partnership in the regular course of its business, including books of account and records of Partnership proceedings, may be kept on, or be in the form of, computer disks, hard drives, punch cards, magnetic tape, photographs, micrographics or any other information storage device; provided, that the books and records so maintained are convertible into clearly legible written form within a reasonable period of time. The books of the Partnership shall be maintained, for financial reporting purposes, on an accrual basis in accordance with U.S. GAAP.

Section 8.2 Fiscal Year. The fiscal year of the Partnership shall be a fiscal year ending December 31.

ARTICLE IX

TAX MATTERS

Section 9.1 Tax Returns and Information. The Partnership shall timely file all returns of the Partnership that are required for federal, state and local income tax purposes on the basis of the accrual method and a taxable year ending on December 31. The tax information reasonably required by the Partners for federal and state income tax reporting purposes with respect to a taxable year shall be furnished to them within 90 days of the close of the calendar

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year in which the Partnership's taxable year ends. The classification, realization and recognition of income, gain, losses and deductions and other items shall be on the accrual method of accounting for federal income tax purposes.

Section 9.2 Tax Elections.

(a) To the extent applicable for federal income tax purposes, the Partnership shall make the election under Section 754 of the Code in accordance with applicable regulations thereunder, subject to the reservation of the right to seek to revoke any such election upon the General Partner's determination that such revocation is in the best interests of the Limited Partners.

(b) To the extent applicable for federal income tax purposes, the Partnership shall elect to deduct expenses incurred in organizing the Partnership ratably over a sixty-month period as provided in Section 709 of the Code.

(c) Except as otherwise provided herein, the General Partner shall determine whether the Partnership should make any other elections permitted by the Code.

Section 9.3 Tax Controversies. Subject to the provisions hereof, the General Partner is designated as the Tax Matters Partner (as defined in the Code) and is authorized and required to represent the Partnership (at the Partnership's expense) in connection with all examinations of the Partnership's affairs by tax authorities, including resulting administrative and judicial proceedings, and to expend Partnership funds for professional services and costs associated therewith. Each Partner agrees to cooperate with the General Partner and to do or refrain from doing any or all things reasonably required by the General Partner to conduct such proceedings.

Section 9.4 Withholding. Notwithstanding any other provision of this Agreement, the General Partner is authorized to take any action that it determines in its discretion to be necessary or appropriate to cause the Partnership to comply with any withholding requirements established under the Code or any other federal, state or local law including, without limitation, pursuant to Sections 1441, 1442, 1445 and 1446 of the Code. To the extent that the Partnership is required or elects to withhold and pay over to any taxing authority any amount resulting from the allocation or distribution of income to any Partner or Assignee (including, without limitation, by reason of Section 1446 of the Code), the amount withheld may at the discretion of the General Partner be treated by the Partnership as a distribution of cash pursuant to
Section 6.3 in the amount of such withholding from such Partner.

ARTICLE X

ADMISSION OF PARTNERS

Section 10.1 Admission of Partners. As a result of the consummation of the transfers and conveyances described in Section 5.2, the General Partner shall be the sole General Partner of the Partnership and the MLP shall be the sole Limited Lartner of the Partnership.

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Section 10.2 Admission of Substituted Limited Partner. By transfer of a Limited Partner Interest in accordance with Article IV, the transferor shall be deemed to have given the transferee the right to seek admission as a Substituted Limited Partner subject to the conditions of, and in the manner permitted under, this Agreement. A transferor of a Limited Partner Interest shall, however, only have the authority to convey to a purchaser or other transferee (a) the right to negotiate such Limited Partner Interest to a purchaser or other transferee and (b) the right to request admission as a Substituted Limited Partner to such purchaser or other transferee in respect of the transferred Limited Partner Interests. Each transferee of a Limited Partner Interest shall be an Assignee and be deemed to have applied to become a Substituted Limited Partner with respect to the Limited Partner Interests so transferred to such Person. Such Assignee shall become a Substituted Limited Partner (x) at such time as the General Partner consents thereto, which consent may be given or withheld in the General Partner's discretion, and (y) when any such admission is shown on the books and records of the Partnership. If such consent is withheld, such transferee shall remain an Assignee. An Assignee shall have an interest in the Partnership equivalent to that of a Limited Partner with respect to allocations and distributions, including liquidating distributions, of the Partnership. With respect to voting rights attributable to Limited Partner Interests that are held by Assignees, the General Partner shall be deemed to be the Limited Partner with respect thereto and shall, in exercising the voting rights in respect of such Limited Partner Interests on any matter, vote such Limited Partner Interests at the written direction of the Assignee. If no such written direction is received, such Partnership Interests will not be voted. An Assignee shall have no other rights of a Limited Partner.

Section 10.3 Admission of Additional Limited Partners.

(a) A Person (other than the General Partner, the MLP or a Substituted Limited Partner) who makes a Capital Contribution to the Partnership in accordance with this Agreement shall be admitted to the Partnership as an Additional Limited Partner only upon furnishing to the General Partner:

(i) evidence of acceptance in form satisfactory to the General Partner of all of the terms and conditions of this Agreement, including the power of attorney granted in Section 2.6, and

(ii) such other documents or instruments as may be required in the discretion of the General Partner to effect such Person's admission as an Additional Limited Partner.

(b) Notwithstanding anything to the contrary in this Section 10.3, no Person shall be admitted as an Additional Limited Partner without the consent of the General Partner, which consent may be given or withheld in the General Partner's discretion. The admission of any Person as an Additional Limited Partner shall become effective on the date upon which the name of such Person is recorded as such in the books and records of the Partnership, following the consent of the General Partner to such admission.

Section 10.4 Admission of Successor or Transferee General Partner. A successor General Partner approved pursuant to Section 11.1 or 11.2 or the transferee of or successor to all

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of the General Partner's Partnership Interest pursuant to Section 4.2 who is proposed to be admitted as a successor General Partner shall, subject to compliance with the terms of Section 11.3, if applicable, be admitted to the Partnership as the General Partner, effective immediately prior to the withdrawal or removal of the predecessor or transferring General Partner pursuant to Section 11.1 or 11.2 or the transfer of the General Partner Interest pursuant to Section 4.2, provided, however, that no such successor shall be admitted to the Partnership until compliance with the terms of Section 4.2 has occurred and such successor has executed and delivered such other documents or instruments as may be required to effect such admission. Any such successor shall, subject to the terms hereof, carry on the business of the members of the Partnership Group without dissolution.

Section 10.5 Amendment of Agreement and Certificate of Limited Partnership. To effect the admission to the Partnership of any Partner, the General Partner shall take all steps necessary and appropriate under the Delaware Act to amend the records of the Partnership to reflect such admission and, if necessary, to prepare as soon as practicable an amendment to this Agreement and, if required by law, the General Partner shall prepare and file an amendment to the Certificate of Limited Partnership, and the General Partner may for this purpose, among others, exercise the power of attorney granted pursuant to Section 2.6.

ARTICLE XI

WITHDRAWAL OR REMOVAL OF PARTNERS

Section 11.1 Withdrawal of the General Partner.

(a) The General Partner shall be deemed to have withdrawn from the Partnership upon the occurrence of any one of the following events (each such event herein referred to as an "Event of Withdrawal");

(i) The General Partner voluntarily withdraws from the Partnership by giving written notice to the other Partners;

(ii) The General Partner transfers all of its rights as General Partner pursuant to Section 4.2;

(iii) The General Partner is removed pursuant to Section 11.2;

(iv) The General Partner (A) makes a general assignment for the benefit of creditors; (B) files a voluntary bankruptcy petition for relief under Chapter 7 of the United States Bankruptcy Code; (C) files a petition or answer seeking for itself a liquidation, dissolution or similar relief (but not a reorganization) under any law; (D) files an answer or other pleading admitting or failing to contest the material allegations of a petition filed against the General Partner in a proceeding of the type described in clauses (A)-(C) of this
Section 11.1(a)(iv); or (E) seeks, consents to or acquiesces in the appointment of a trustee (but not a debtor-in-possession), receiver or liquidator of the General Partner or of all or any substantial part of its properties;

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(v) A final and non-appealable order of relief under Chapter 7 of the United States Bankruptcy Code is entered by a court with appropriate jurisdiction pursuant to a voluntary or involuntary petition by or against the General Partner; or

(vi) (A) in the event the General Partner is a corporation, a certificate of dissolution or its equivalent is filed for the General Partner, or 90 days expire after the date of notice to the General Partner of revocation of its charter without a reinstatement of its charter, under the laws of its state of incorporation; (B) in the event the General Partner is a partnership or limited liability company, the dissolution and commencement of winding up of the General Partner; (C) in the event the General Partner is acting in such capacity by virtue of being a trustee of a trust, the termination of the trust; (D) in the event the General Partner is a natural person, his death or adjudication of incompetency; and (E) otherwise in the event of the termination of the General Partner. If an Event of Withdrawal specified in Section 11.1(a)(iv), (v) or
(vi)(A), (B), (C) or (E) occurs, the withdrawing General Partner shall give notice to the Limited Partners within 30 days after such occurrence. The Partners hereby agree that only the Events of Withdrawal described in this
Section 11.1 shall result in the withdrawal of the General Partner from the Partnership.

(b) Withdrawal of the General Partner from the Partnership upon the occurrence of an Event of Withdrawal shall not constitute a breach of this Agreement under the following circumstances: (i) at any time during the period beginning on the Closing Date and ending at 12:00 midnight, Eastern Time, on October 31, 2008, the General Partner voluntarily withdraws by giving at least 90 days' advance notice of its intention to withdraw to the Limited Partners; provided that prior to the effective date of such withdrawal, the withdrawal is approved by the Limited Partners and the General Partner delivers to the Partnership an Opinion of Counsel ("Withdrawal Opinion of Counsel") that such withdrawal (following the selection of the successor General Partner) would not result in the loss of the limited liability of any Limited Partner or of the limited partners of the MLP or cause the Partnership or the MLP to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not previously treated as such);
(ii) at any time after 12:00 midnight, Eastern Standard Time, on October 31, 2008, the General Partner voluntarily withdraws by giving at least 90 days' advance notice to the Limited Partners, such withdrawal to take effect on the date specified in such notice; (iii) at any time that the General Partner ceases to be the General Partner pursuant to Section 11.1(a)(ii) or (iii). If the General Partner gives a notice of withdrawal pursuant to Section 11.1(a)(i) hereof, the Limited Partners may, prior to the effective date of such withdrawal, elect a successor General Partner. If, prior to the effective date of the General Partner's withdrawal, a successor is not selected by the Limited Partners as provided herein or the Partnership does not receive a Withdrawal Opinion of Counsel, the Partnership shall be dissolved in accordance with
Section 12.1. Any successor General Partner elected in accordance with the terms of this Section 11.1 shall be subject to the provisions of Section 10.3.

Section 11.2 Removal of the General Partner. The General Partner may be removed by the MLP. Upon the removal of the General Partner by the MLP, the MLP shall elect a successor general partner for the Partnership. The admission of any such successor General Partner to the Partnership shall be subject to the provisions of Section 10.3.

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Section 11.3 Interest of Departing Partner.

(a) The Partnership Interest of the Departing Partner departing as a result of withdrawal or removal pursuant to Section 11.1 or 11.2 shall be purchased by the successor to the Departing Partner for an amount in cash equal to the fair market value of such Partnership Interest, such amount to be determined and payable as of the effective date of the Departing Partner's departure. Such purchase shall be a condition to the admission to the Partnership of the successor as the General Partner. Any successor General Partner shall indemnify the Departing Partner as to all debts and liabilities of the Partnership arising on or after the effective date of the withdrawal or removal of the Departing Partner.

For purposes of this Section 11.3(a), the fair market value of the Departing Partner's General Partner Interest shall be determined by agreement between the Departing Partner and its successor or, failing agreement within 30 days after the effective date of such Departing Partner's departure, by an independent investment banking firm or other independent expert selected by the Departing Partner and its successor, which, in turn, may rely on other experts, and the determination of which shall be conclusive as to such matter. If such parties cannot agree upon one independent investment banking firm or other independent expert within 45 days after the effective date of such departure, then the Departing Partner shall designate an independent investment banking firm or other independent expert, the Departing Partner's successor shall designate an independent investment banking firm or other independent expert, and such firms or experts shall mutually select a third independent investment banking firm or independent expert, which third independent investment banking firm or other independent expert shall determine the fair market value of the General Partner Interest of the Departing Partner. In making its determination, such third independent investment banking firm or other independent expert may consider the value of the Partnership's assets, the rights and obligations of the Departing Partner and other factors it may deem relevant.

(b) The Departing Partner shall be entitled to receive all reimbursements due such Departing Partner pursuant to Section 7.4, including any employee-related liabilities (including severance liabilities), incurred in connection with the termination of any employees employed by such Departing Partner for the benefit of the Partnership.

Section 11.4 Withdrawal of a Limited Partner. Without the prior written consent of the General Partner, which may be granted or withheld in its sole discretion, and except as provided in Section 10.1, no Limited Partner shall have the right to withdraw from the Partnership.

ARTICLE XII

DISSOLUTION AND LIQUIDATION

Section 12.1 Dissolution. The Partnership shall not be dissolved by the admission of Substituted Limited Partners or Additional Limited Partners or by the admission of a successor General Partner in accordance with the terms of this Agreement. Upon the removal or withdrawal of the General Partner, if a successor General Partner is elected pursuant to Section 11.1 or 11.2, the Partnership shall not be dissolved and such successor General Partner shall

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continue the business of the Partnership. The Partnership shall dissolve, and (subject to Section 12.2) its affairs shall be wound up, upon:

(a) an Event of Withdrawal of the General Partner as provided in
Section 11.1(a) (other than Section 11.1(a)(ii)), unless a successor is elected and an Opinion of Counsel is received as provided in Section 11.1(b) or 11.2 and such successor is admitted to the Partnership pursuant to Section 10.4;

(b) an election to dissolve the Partnership by the General Partner that is approved by all of the Limited Partners;

(c) the entry of a decree of judicial dissolution of the Partnership pursuant to the provisions of the Delaware Act;

(d) the sale of all or substantially all of the assets and properties of the Partnership Group; or

(e) the dissolution of the MLP.

Section 12.2 Continuation of the Business of the Partnership After Dissolution. Upon dissolution of the Partnership following an Event of Withdrawal caused by the withdrawal or removal of the General Partner as provided in Section 11.1(a)(i) or (iii) and the failure of the Partners to select a successor to such Departing Partner pursuant to Section 11.1 or 11.2,
then within 90 days thereafter, all of the Limited Partners may elect to reconstitute the Partnership and continue its business on the same terms and conditions set forth in this Agreement by forming a new limited partnership on terms identical to those set forth in this Agreement and having as a general partner a Person approved by a majority in interest of the Limited Partners. In addition, upon dissolution of the Partnership pursuant to Section 12.1(e), if the MLP is reconstituted pursuant to Section 12.2 of the MLP Agreement, the reconstituted MLP may, within 180 days after such event of dissolution, acting alone, regardless of whether there are any other Limited Partners, elect to reconstitute the Partnership in accordance with the immediately preceding sentence. Upon any such election by the Limited Partners or the MLP, as the case may be, all Partners shall be bound thereby and shall be deemed to have approved same. Unless such an election is made within the applicable time period as set forth above, the Partnership shall conduct only activities necessary to wind up its affairs. If such an election is so made, then:

(a) the reconstituted Partnership shall continue unless earlier dissolved in accordance with this Article XII;

(b) if the successor General Partner is not the former General Partner, then the interest of the former General Partner shall be purchased by the successor General Partner; and

(c) all necessary steps shall be taken to cancel this Agreement and the Certificate of Limited Partnership and to enter into and, as necessary, to file, a new partnership agreement and certificate of limited partnership, and the successor General Partner may for this purpose exercise the powers of attorney granted the General Partner pursuant to Section 2.6; provided, that the right to approve a successor General Partner and to reconstitute and to

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continue the business of the Partnership shall not exist and may not be exercised unless the Partnership has received an Opinion of Counsel that (x) the exercise of the right would not result in the loss of limited liability of the Limited Partners or any limited partner of the MLP and (y) neither the Partnership, the reconstituted limited partnership, the MLP nor any Group Member would be treated as an association taxable as a corporation or otherwise be taxable as an entity for federal income tax purposes upon the exercise of such right to continue.

Section 12.3 Liquidator. Upon dissolution of the Partnership, unless the Partnership is continued under an election to reconstitute and continue the Partnership pursuant to Section 12.2, the General Partner shall select one or more Persons to act as Liquidator. The Liquidator (if other than the General Partner) shall be entitled to receive such compensation for its services as may be approved by a majority of the Limited Partners. The Liquidator (if other than the General Partner) shall agree not to resign at any time without 15 days' prior notice and may be removed at any time, with or without cause, by notice of removal approved by a majority in interest of the Limited Partners. Upon dissolution, removal or resignation of the Liquidator, a successor and substitute Liquidator (who shall have and succeed to all rights, powers and duties of the original Liquidator) shall within 30 days thereafter be approved by at least a majority in interest of the Limited Partners. The right to approve a successor or substitute Liquidator in the manner provided herein shall be deemed to refer also to any such successor or substitute Liquidator approved in the manner herein provided. Except as expressly provided in this Article XII, the Liquidator approved in the manner provided herein shall have and may exercise, without further authorization or consent of any of the parties hereto, all of the powers conferred upon the General Partner under the terms of this Agreement (but subject to all of the applicable limitations, contractual and otherwise, upon the exercise of such powers, other than the limitation on sale set forth in Section 7.3(b)) to the extent necessary or desirable in the good faith judgment of the Liquidator to carry out the duties and functions of the Liquidator hereunder for and during such period of time as shall be reasonably required in the good faith judgment of the Liquidator to complete the winding up and liquidation of the Partnership as provided for herein.

Section 12.4 Liquidation. The Liquidator shall proceed to dispose of the assets of the Partnership, discharge its liabilities, and otherwise wind up its affairs in such manner and over such period as the Liquidator determines to be in the best interest of the Partners, subject to Section 17-804 of the Delaware Act and the following:

(a) Disposition of Assets. The assets may be disposed of by public or private sale or by distribution in kind to one or more Partners on such terms as the Liquidator and such Partner or Partners may agree. If any property is distributed in kind, the Partner receiving the property shall be deemed for purposes of Section 12.4(c) to have received cash equal to its fair market value; and contemporaneously therewith, appropriate cash distributions must be made to the other Partners. The Liquidator may, in its absolute discretion, defer liquidation or distribution of the Partnership's assets for a reasonable time if it determines that an immediate sale or distribution of all or some of the Partnership's assets would be impractical or would cause undue loss to the Partners. The Liquidator may, in its absolute discretion, distribute the Partnership's assets, in whole or in part, in kind if it determines that a sale would be impractical or would cause undue loss to the Partners.

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(b) Discharge of Liabilities. Liabilities of the Partnership include amounts owed to the Liquidator as compensation for serving in such capacity (subject to the terms of Section 12.3) and amounts owed to Partners otherwise than in respect of their distribution rights under Article VI. With respect to any liability that is contingent, conditional or unmatured or is otherwise not yet due and payable, the Liquidator shall either settle such claim for such amount as it thinks appropriate or establish a reserve of cash or other assets to provide for its payment. When paid, any unused portion of the reserve shall be distributed as additional liquidation proceeds.

(c) Liquidation Distributions. All property and all cash in excess of that required to discharge liabilities as provided in Section 12.4(b) shall be distributed to the Partners in accordance with, and to the extent of, the positive balances in their respective Capital Accounts, as determined after taking into account all Capital Account adjustments (other than those made by reason of distributions pursuant to this Section 12.4(c)) for the taxable year of the Partnership during which the liquidation of the Partnership occurs (with such date of occurrence being determined pursuant to Treasury Regulation Section 1.704-1(b)(2)(ii)(g)), and such distribution shall be made by the end of such taxable year (or, if later, within 90 days after said date of such occurrence).

Section 12.5 Cancellation of Certificate of Limited Partnership. Upon the completion of the distribution of Partnership cash and property as provided in Section 12.4 in connection with the liquidation of the Partnership, the Partnership shall be terminated and the Certificate of Limited Partnership, and all qualifications of the Partnership as a foreign limited partnership in jurisdictions other than the State of Delaware, shall be canceled and such other actions as may be necessary to terminate the Partnership shall be taken.

Section 12.6 Return of Contributions. The General Partner shall not be personally liable for, and shall have no obligation to contribute or loan any monies or property to the Partnership to enable it to effectuate, the return of the Capital Contributions of the Limited Partners, or any portion thereof, it being expressly understood that any such return shall be made solely from Partnership assets.

Section 12.7 Waiver of Partition. To the maximum extent permitted by law, each Partner hereby waives any right to partition of the Partnership property.

Section 12.8 Capital Account Restoration. No Limited Partner shall have any obligation to restore any negative balance in its Capital Account upon liquidation of the Partnership. The General Partner shall be obligated to restore any negative balance in its Capital Account upon liquidation of its interest in the Partnership by the end of the taxable year of the Partnership during which such liquidation occurs, or, if later, within 90 days after the date of such liquidation.

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ARTICLE XIII

AMENDMENT OF PARTNERSHIP AGREEMENT

Section 13.1 Amendment to be Adopted Solely by the General Partner. Each Partner agrees that the General Partner, without the approval of any Partner or Assignee, may amend any provision of this Agreement and execute, swear to, acknowledge, deliver, file and record whatever documents may be required in connection therewith, to reflect:

(a) a change in the name of the Partnership, the location of the principal place of business of the Partnership, the registered agent of the Partnership or the registered office of the Partnership;

(b) admission, substitution, withdrawal or removal of Partners in accordance with this Agreement;

(c) a change that, in the sole discretion of the General Partner, is necessary or advisable to qualify or continue the qualification of the Partnership as a limited partnership or a partnership in which the Limited Partners have limited liability under the laws of any state or to ensure that no Group Member will be treated as an association taxable as a corporation or otherwise taxed as an entity for federal income tax purposes;

(d) a change that, in the discretion of the General Partner, (i) does not adversely affect the Limited Partners (including any particular class of Partnership Interests as compared to other classes of Partnership Interests) in any material respect, (ii) is necessary or advisable to (A) satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or judicial authority or contained in any federal or state statute (including the Delaware Act) or (B) facilitate the trading of limited partner interests of the MLP (including the division of any class or classes of outstanding limited partner interests of the MLP into different classes to facilitate uniformity of tax consequences within such classes of limited partner interests of the MLP) or comply with any rule, regulation, guideline or requirement of any National Securities Exchange on which such limited partner interests are or will be listed for trading, compliance with any of which the General Partner determines in its discretion to be in the best interests of the MLP and the limited partners of the MLP, (iii) is required to effect the intent expressed in the Registration Statement or the intent of the provisions of this Agreement or is otherwise contemplated by this Agreement or (iv) is required to conform the provisions of this Agreement with the provisions of the MLP Agreement as the provisions of the MLP Agreement may be amended, supplemented or restated from time to time;

(e) a change in the fiscal year or taxable year of the Partnership and any changes that, in the discretion of the General Partner, are necessary or advisable as a result of a change in the fiscal year or taxable year of the Partnership including, if the General Partner shall so determine, a change in the definition of "Quarter" and the dates on which distributions are to be made by the Partnership;

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(f) an amendment that is necessary, in the Opinion of Counsel, to prevent the Partnership, or the General Partner or its members, directors, officers, trustees or agents from in any manner being subjected to the provisions of the Investment Company Act of 1940, as amended, the Investment Advisers Act of 1940, as amended, or "plan asset" regulations adopted under the Employee Retirement Income Security Act of 1974, as amended, regardless of whether such are substantially similar to plan asset regulations currently applied or proposed by the United States Department of Labor;

(g) any amendment expressly permitted in this Agreement to be made by the General Partner acting alone;

(h) an amendment effected, necessitated or contemplated by a Merger Agreement approved in accordance with Section 14.3;

(i) an amendment that, in the discretion of the General Partner, is necessary or advisable to reflect, account for and deal with appropriately the formation by the Partnership of, or investment by the Partnership in, any corporation, partnership, joint venture, limited liability company or other entity, in connection with the conduct by the Partnership of activities permitted by the terms of Section 2.4;

(j) a merger or conveyance pursuant to Section 14.3(d); or

(k) any other amendments substantially similar to the foregoing.

Section 13.2 Amendment Procedures. Except with respect to amendments of the type described in Section 13.1, all amendments to this Agreement shall be made in accordance with the following requirements: Amendments to this Agreement may be proposed only by or with the consent of the General Partner, which consent may be given or withheld in its sole discretion. A proposed amendment shall be effective upon its approval by the Limited Partners.

ARTICLE XIV

MERGER

Section 14.1 Authority. The Partnership may merge or consolidate with one or more corporations, limited liability companies, business trusts or associations, real estate investment trusts, common law trusts or unincorporated businesses, including a general partnership or limited partnership, formed under the laws of the State of Delaware or any other state of the United States of America, pursuant to a written agreement of merger or consolidation ("Merger Agreement") in accordance with this Article XIV.
------                                ------------

  Section  14.2     Procedure  for  Merger  or  Consolidation.  Merger  or
                    -----------------------------------------

consolidation of the Partnership pursuant to this Article XIV requires the prior approval of the General Partner. If the General Partner shall determine, in the exercise of its discretion, to consent to the merger or consolidation, the General Partner shall approve the Merger Agreement, which shall set forth:

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(a) the names and jurisdictions of formation or organization of each of the business entities proposing to merge or consolidate;

(b) the name and jurisdiction of formation or organization of the business entity that is to survive the proposed merger or consolidation (the "Surviving Business Entity");

(c) the terms and conditions of the proposed merger or consolidation;

(d) the manner and basis of exchanging or converting the equity securities of each constituent business entity for, or into, cash, property or general or limited partner interests, rights, securities or obligations of the Surviving Business Entity; and (i) if any general or limited partner interests, securities or rights of any constituent business entity are not to be exchanged or converted solely for, or into, cash, property or general or limited partner interests, rights, securities or obligations of the Surviving Business Entity, the cash, property or general or limited partner interests, rights, securities or obligations of any limited partnership, corporation, trust or other entity (other than the Surviving Business Entity) that the holders of such general or limited partner interests, securities or rights are to receive in exchange for, or upon conversion of their general or limited partner interests, securities or rights, and (ii) in the case of securities represented by certificates, upon the surrender of such certificates, which cash, property or general or limited partner interests, rights, securities or obligations of the Surviving Business Entity or any general or limited partnership, corporation, trust or other entity (other than the Surviving Business Entity), or evidences thereof, are to be delivered;

(e) a statement of any changes in the constituent documents or the adoption of new constituent documents (the articles or certificate of incorporation, articles of trust, declaration of trust, certificate or agreement of limited partnership or other similar charter or governing document) of the Surviving Business Entity to be effected by such merger or consolidation;

(f) the effective time of the merger, which may be the date of the filing of the certificate of merger pursuant to Section 14.4 or a later date specified in or determinable in accordance with the Merger Agreement (provided, that if the effective time of the merger is to be later than the date of the filing of the certificate of merger, the effective time shall be fixed no later than the time of the filing of the certificate of merger and stated therein); and

(g) such other provisions with respect to the proposed merger or consolidation as are deemed necessary or appropriate by the General Partner.

Section 14.3 Approval by Limited Partners of Merger or Consolidation.

(a) Except as provided in Section 14.3(d), the General Partner, upon its approval of the Merger Agreement, shall direct that the Merger Agreement be submitted to a vote of the Limited Partners, whether at a special meeting or by written consent, in either case in accordance with the requirements of Article XIII. A copy or a summary of the Merger Agreement shall be included in or enclosed with the notice of a special meeting or the written consent.

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(b) Except as provided in Section 14.3(d), the Merger Agreement shall be approved upon receiving the affirmative vote or consent of the Limited Partners.

(c) Except as provided in Section 14.3(d), after such approval by vote or consent of the Limited Partners, and at any time prior to the filing of the certificate of merger pursuant to Section 14.4, the merger or consolidation may be abandoned pursuant to provisions therefor, if any, set forth in the Merger Agreement.

(d) Notwithstanding anything else contained in this Article XIV or in this Agreement, the General Partner is permitted, in its discretion, without Limited Partner approval, to merge the Partnership or any Group Member into, or convey all of the Partnership's assets to, another limited liability entity that shall be newly formed and shall have no assets, liabilities or operations at the time of such Merger other than those it receives from the Partnership or other Group Member if (i) the General Partner has received an Opinion of Counsel that the merger or conveyance, as the case may be, would not result in the loss of the limited liability of any Limited Partner or any limited partner in the MLP or cause the Partnership or the MLP to be treated as an association taxable as a corporation or otherwise to be taxed as an entity for federal income tax purposes (to the extent not previously treated as such), (ii) the sole purpose of such merger or conveyance is to effect a mere change in the legal form of the Partnership into another limited liability entity and (iii) the governing instruments of the new entity provide the Limited Partners and the General Partner with substantially the same rights and obligations as are herein contained.

Section 14.4 Certificate of Merger. Upon the required approval by the General Partner and the Limited Partners of a Merger Agreement, a certificate of merger shall be executed and filed with the Secretary of State of the State of Delaware in conformity with the requirements of the Delaware Act.

Section 14.5 Effect of Merger.

(a) At the effective time of the certificate of merger:

(i) all of the rights, privileges and powers of each of the business entities that has merged or consolidated, and all property, real, personal and mixed, and all debts due to any of those business entities and all other things and causes of action belonging to each of those business entities, shall be vested in the Surviving Business Entity and after the merger or consolidation shall be the property of the Surviving Business Entity to the extent they were of each constituent business entity;

(ii) the title to any real property vested by deed or otherwise in any of those constituent business entities shall not revert and is not in any way impaired because of the merger or consolidation;

(iii) all rights of creditors and all liens on or security interests in property of any of those constituent business entities shall be preserved unimpaired; and

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(iv) all debts, liabilities and duties of those constituent business entities shall attach to the Surviving Business Entity and may be enforced against it to the same extent as if the debts, liabilities and duties had been incurred or contracted by it.

(b) A merger or consolidation effected pursuant to this Article shall not be deemed to result in a transfer or assignment of assets or liabilities from one entity to another.

ARTICLE XV

GENERAL PROVISIONS

Section 15.1 Addresses and Notices. Any notice, demand, request, report or proxy materials required or permitted to be given or made to a Partner or Assignee under this Agreement shall be in writing and shall be deemed given or made when delivered in person or when sent by first class United States mail or by other means of written communication to the Partner or Assignee at the address appearing on the books and records of the Partnership. Any notice to the Partnership shall be deemed given if received by the General Partner at the principal office of the Partnership designated pursuant to Section 2.3. The General Partner may rely and shall be protected in relying on any notice or other document from a Partner, Assignee or other Person if believed by it to be genuine.

Section 15.2 Further Action. The parties shall execute and deliver all documents, provide all information and take or refrain from taking action as may be necessary or appropriate to achieve the purposes of this Agreement.

Section 15.3 Binding Effect. This Agreement shall be binding upon and inure to the benefit of the parties hereto and their heirs, executors, administrators, successors, legal representatives and permitted assigns.

Section 15.4 Integration. This Agreement constitutes the entire agreement among the parties hereto pertaining to the subject matter hereof and supersedes all prior agreements and understandings pertaining thereto.

Section 15.5 Creditors. None of the provisions of this Agreement shall be for the benefit of, or shall be enforceable by, any creditor of the Partnership.

Section 15.6 Waiver. No failure by any party to insist upon the strict performance of any covenant, duty, agreement or condition of this Agreement or to exercise any right or remedy consequent upon a breach thereof shall constitute waiver of any breach of any other covenant, duty, agreement or condition.

Section 15.7 Counterparts. This Agreement may be executed in counterparts, all of which together shall constitute an agreement binding on all the parties hereto, notwithstanding that all such parties are not signatories to the original or the same counterpart. Each party shall become bound by this Agreement immediately upon affixing its signature hereto, independently of the signature of any other party.

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Section 15.8 Applicable Law. This Agreement shall be construed in accordance with and governed by the laws of the State of Delaware, without regard to the principles of conflicts of law.

Section 15.9 Invalidity of Provisions. If any provision of this Agreement is or becomes invalid, illegal or unenforceable in any respect, the validity, legality and enforceability of the remaining provisions contained herein shall not be affected thereby.

Section 15.10 Consent of Partners. Each Partner hereby expressly consents and agrees that, whenever in this Agreement it is specified that an action may be taken upon the affirmative vote or consent of less than all of the Partners, such action may be so taken upon the concurrence of less than all of the Partners and each Partner shall be bound by the results of such action.

[Remainder of Page Intentionally Left Blank]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first written above.

GENERAL PARTNER:

RIO VISTA OPERATING GP LLC

By: Rio Vista Energy Partners, L.P.
its Managing Member

By: Rio Vista GP LLC
Its: General Partner

By:  /s/ Richard Shore, Jr.
     -------------------------
         Richard Shore, Jr.,
         President

LIMITED PARTNERS:

PENN OCTANE CORPORATION

By:  /s/ Richard Shore, Jr.
     -------------------------
         Richard Shore, Jr.,
         President

UPON CONSUMMATION OF THE TRANSACTIONS
CONTEMPLATED UNDER SECTION 5.2 OF THIS
AGREEMENT:

RIO VISTA ENERGY PARTNERS L.P.

By: Rio Vista GP LLC
Its General Partner

By:  /s/ Richard Shore, Jr.
     -------------------------
         Richard Shore, Jr.,
         President

53

Amended and Restated Line Letter

September 15, 2004

Penn Octane Corporation
77-530 Enfield Lane
Building D
Palm Desert, CA 92211

Attention: Mr. Jerome Richter

Gentlemen:

RZB FINANCE LLC ("RZB") and Penn Octane Corporation (the "Borrower") are parties to a Line Letter dated October 14, 1997 (as heretofore amended, the "Existing Line Letter"). The Borrower and RZB desire to amend and restate the Existing Line Letter. Accordingly, the parties hereto agree that the Existing Line Letter is hereby amended and restated in its entirety as hereinafter set forth in this Agreement (as amended, modified or supplemented from time to time, "this Agreement" or "this letter agreement"). On or after the date hereof, when counterparts of this Agreement shall have been executed by all parties hereto,
(a) all references to the "Agreement" and words of similar import in the other Loan Documents shall be deemed to refer to the Existing Line Letter as amended and restated hereby, and (b) all outstanding loans and extensions of credit under the Existing Line Letter shall be loans and extensions of credit under and subject to the terms and conditions of this Agreement and the Loan Documents (as hereinafter defined).

We wish to advise you of the terms and conditions upon which RZB may in its sole discretion extend credit to the Borrower.

1. (a) Subject to the provisions hereof, the Borrower may utilize this credit facility (the "Credit Facility") for demand loans ("Loans") and issuance of standby and commercial letters of credit ("L/C's") in the aggregate principal sum and face amount of up to Fifteen Million Dollars ($15,000,000) at any one time outstanding. Notwithstanding the foregoing, and without in any way limiting RZB's sole and absolute discretion to determine whether to make any Loan or issue any L/C, or refrain therefrom (as more fully set forth below), and without in any way limiting RZB's absolute right to demand payment of any Loan at any time or to change any of the Advance Rates (as hereinafter defined), at any time in RZB's sole discretion, the Borrower acknowledges that, with respect to each specific transaction of the Borrower financed by RZB pursuant hereto, the sum of (i) the Loans made by RZB in connection with such transaction, (ii) the aggregate face amount of L/Cs issued in connection therewith, plus (iii) the aggregate unreimbursed amount of all drawings under such L/Cs, shall not exceed the amount obtained by applying the Advance Rates (the "Advance Rates") to the

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value of the assets of the Borrower being financed by RZB in such transaction (as such value may be determined by RZB in its sole discretion).

Within the above Credit Facility, there shall be a sublimit not to exceed Three Million Dollars ($3,000,000) at any time outstanding available for the issuance of standby letters of credit from time to time for the financing of the purchase of diesel fuel and gasoline fuel. The terms and beneficiary of each such letter of credit shall be subject to RZB's approval in its sole discretion. Prior to the issuance of any standby letter of credit described in clause (i) above, the Borrower shall deposit cash collateral with RZB in an amount equal to 15% of the maximum face amount of such letter of credit. The Borrower hereby grants to RZB a lien on and security interest in such cash collateral and all deposit accounts in which such cash collateral and all proceeds thereof shall be maintained as security for all present and future obligations of the Borrower to RZB until the letter of credit expires or is terminated and all obligations in connection therewith shall have been satisfied in full in cash to the sole and absolute satisfaction of RZB, provided, however, that no lien on and security interest in cash collateral shall be released nor shall any cash collateral be released if any Event of Default under any security agreement delivered in connection with this Agreement shall have occurred and be continuing (an "Event of Default") or any event that with the giving of notice or lapse of time or both would constitute such an Event of Default (a "Default") shall have occurred and be continuing or any demand for payment of or cash collateral for the obligations of the Borrower under the Credit Facility shall have been made.

Within the above Credit Facility, there shall be a sublimit not to exceed Five Hundred Thousand Dollars ($500,000) at any time outstanding available for the issuance of standby letters of credit from time to time (i) to secure a performance bond with respect to Arizona and Nevada excise taxes and
(ii) in favor of Kinder Morgan to secure monthly lease obligations. The terms and beneficiary of each such letter of credit shall be subject to RZB's approval in its sole discretion. Prior to the issuance of any standby letter of credit described in this paragraph, the Borrower shall deposit cash collateral with RZB in an amount equal to 100% of the maximum face amount of such letter of credit. The Borrower hereby grants to RZB a lien on and security interest in such cash collateral and all deposit accounts in which such cash collateral and all proceeds thereof shall be maintained as security for all present and future obligations of the Borrower to RZB until the letter of credit expires or is terminated and all obligations in connection therewith shall have been satisfied in full in cash to the sole and absolute satisfaction of RZB, provided, however, that no lien on and security interest in cash collateral shall be released nor shall any cash collateral be released if any Default or Event of Default shall have occurred and be continuing or any demand for payment of or cash collateral for the obligations of the Borrower under the Credit Facility shall have been made.

(b) For purposes hereof:

"Advance Rates" shall mean, with respect to each transaction of the Borrower financed by RZB pursuant hereto, the following respective percentages of the Borrower's accounts receivable or inventory which is the subject of such transaction (provided, however, that RZB reserves the right to change any or all of the following percentages or

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categories of assets in any way whatsoever, at its sole and absolute discretion, at any time and from time to time, with or without notice to the Borrower):

100% of CIF cost of eligible inventory or 90% of the net face amount of the Borrower's eligible accounts receivable (as such eligibility shall be determined from time to time by RZB in its sole and absolute discretion), whichever is lower.

(c) The Loans shall be evidenced by, and subject to the terms and conditions contained in, a single grid promissory note (the "Note") made by the Borrower in form and substance satisfactory to RZB. Interest on the Loans shall be payable at the rate specified in the Note (the "Interest Rate").

(d) Each Loan hereunder shall be payable on demand, and in no event shall any Loan be outstanding for more than 45 days.

(e) (i) Each L/C shall be in form and substance satisfactory to RZB, and, unless otherwise agreed by RZB, shall have an expiration date not more than 90 days after its date of issuance.

(ii) The Borrower shall pay to RZB a fee with respect to each L/C in an amount equal to the greater of: (1) a flat fee of $500, (2) a fee at a rate per annum equal to 2.5% of the maximum face amount of the L/C
(without regard to whether conditions to drawing may then be satisfied) or (3) such higher amount or percentage as shall be agreed to in writing by the Borrower and RZB with respect to L/Cs issued after the date of such agreement. The fee provided for in clauses (1), (2) and (3) shall be payable upon issuance of each L/C and, in the case of any L/C which as issued, amended or renewed has an expiration date more than 90 days after its original date of issuance, on the same day in each calendar quarter thereafter if such L/C is outstanding on such day. After any such fee is paid it shall be non-refundable.

(f) The Borrower shall reimburse RZB for the amount of each drawing under each L/C on demand, and shall pay interest on the unreimbursed portion of each drawing as provided in the Continuing Agreement for Letters of Credit between the Borrower and RZB.

(g) This credit facility may be terminated at any time at the sole and absolute discretion of RZB.

(h) Without in any way limiting RZB's sole and absolute discretion to make any Loan or issue any L/C, or refrain therefrom (as more fully set forth below), and without in any way limiting RZB's right to change the Advance Rates or demand payment of any Loan at any time in its sole and absolute discretion, the Borrower agrees that it shall, from time to time, pay the Loans and reimbursement obligations in respect of L/Cs and shall deliver cash collateral in respect of outstanding L/Cs, as and when necessary to cause:

the sum of (1) the outstanding balance of all Loans, (2) the aggregate face amount of all outstanding L/Cs, and (3) the aggregate unreimbursed amount of all drawings under L/Cs (as

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such sum may be reduced by the amount of cash collateral maintained with RZB or a bank designated by RZB and pledged in respect of outstanding L/Cs) not to exceed, on any date, the amount obtained by applying the Advance Rates as then in effect to the aggregate value as of such date (as such value shall be determined by RZB in its sole discretion) of all of the assets then owned by the Borrower (without double counting) which are the subject of transactions financed by RZB pursuant hereto and are subject to a perfected first priority security interest in favor of RZB.

(i) The Borrower shall pay to RZB a non-refundable administration fee of $50,000 on the date hereof and thereafter on each anniversary of the date hereof.

2. The proceeds of the Loans and the L/C's shall be used to finance the purchase of inventory, including, within the sublimits set forth in Section 1(a) above, diesel fuel and gasoline fuel, from suppliers which is to be sold to purchasers acceptable to RZB in its sole discretion and accounts receivable arising from the sale of inventory and other transactions acceptable to RZB in its sole discretion.

3. Requests for Loans under this Agreement and directions as to the disposition of the proceeds of Loans shall be given in writing (including by telecopy) by the Borrower to RZB, or may be given orally (including by telephone), provided any such oral communication shall be confirmed promptly to RZB in writing. Requests for L/C's under this Agreement shall be given in writing (including telecopy) by the Borrower to RZB by the execution and delivery of an application satisfactory in form and substance to RZB. Any such Loan so made or L/C issued shall be conclusively presumed to have been made to or for the benefit of, or for the account of, the Borrower when made in accordance with any such request or direction. RZB may rely on any such request or direction which it believes to be genuine, including, without limitation, any oral request whether or not confirmed in writing, and RZB shall be fully protected in so doing without any duty to make any further inquiry as to such genuineness or to otherwise act in good faith in the premises.

4. THE BORROWER AGREES AND ACKNOWLEDGES THAT, NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED OR IMPLIED IN THIS AGREEMENT, RZB SHALL HAVE NO OBLIGATION TO MAKE ANY LOAN OR ISSUE ANY L/C, AND RZB SHALL HAVE THE SOLE AND ABSOLUTE DISCRETION TO MAKE ANY LOAN OR ISSUE ANY L/C OR REFRAIN FROM MAKING ANY LOAN OR ISSUING ANY L/C. THE BORROWER FURTHER AGREES AND ACKNOWLEDGES THAT, NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED OR IMPLIED IN THIS AGREEMENT, ALL OF THE LOANS SHALL BE PAYABLE ON DEMAND, AND RZB MAY DEMAND PAYMENT OF ANY LOAN AND/OR MAY DEMAND CASH COLLATERAL FOR ANY OUTSTANDING L/C AT ANY TIME IN ITS SOLE AND ABSOLUTE DISCRETION.

5. All payments of principal, interest and other sums in connection with the Loans and L/C's shall be payable to RZB at such account as RZB shall designate, or in the absence of such designation, to RZB at its office at 1133 Avenue of the Americas, New York, New York 10036, in lawful money of the United States in immediately available funds and without setoff or deduction. Interest and fees shall be computed on the basis of a 360 day year and the actual number of days elapsed. In the event that such computation would result in a

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usurious rate, then the interest or fee shall be recalculated on a 365 or 366 day year, as the case may be.

All payments of principal, interest, and other sums in connection with this letter agreement, the Loans and L/C's or in respect of any participation in the Credit Facility which may be sold in RZB's discretion to any participant acceptable to RZB (a "Participant") shall be made by the Borrower to RZB or by RZB to the Participant, as applicable, free and clear of, and without deduction or withholding for, any and all present and future taxes, levies, duties or withholdings of any kind or, if any deduction or withholding from any amount payable hereunder or under any other Loan Document or in respect of the participation of the Participant or in connection herewith or therewith shall be legally required, such amount shall be increased by the Borrower as may be necessary so that after making all required deductions or withholdings (including deductions or withholdings applicable to additional amounts payable under this paragraph 5) RZB or the Participant shall receive an amount equal to the amount it would have received had no such deductions or withholdings been required. The Borrower shall pay to RZB promptly upon the Participant's request, and RZB shall promptly pay to the Participant, any amount payable to the Participant pursuant to the preceding sentence, but RZB shall have no liability under this paragraph to the Participant for any amount which is not received by RZB from the Borrower.

6. Without limiting the discretionary nature of the credit facility hereunder, the making of each Loan and the issuance of each L/C shall be subject to the fulfillment (to the satisfaction of RZB) of the following conditions precedent, provided that all of the following conditions precedent to the extent relating to RVEP and the Operating Partnership shall be waived by RZB until RZB withdraws such waiver and gives notice of such withdrawal to the Borrower :

(a) The Borrower shall have executed and delivered to RZB the Note(s) evidencing the Loans and a Continuing Agreement for Letters of Credit in form and substance satisfactory to RZB;

(b) The Borrower, Rio Vista Energy Partners L.P. ("RVEP") and Rio Vista Operating Partnership L.P. (the "Operating Partnership") (the Borrower, RVEP and the Operating Partnership are collectively referred to as the "Loan Parties") shall have delivered to RZB such documents of title, and other instruments and documents, pertaining to the transaction of the Borrower which is being financed in connection with such Loan or L/C, as RZB shall require, and all of the foregoing shall be in form and substance, and contain such endorsements, as shall be satisfactory to RZB in all respects;

(c) Each Loan Party shall have complied and shall then be in compliance with all of the terms, covenants and conditions of this Agreement and the Loan Documents (as hereinafter defined in Section 11(c));

(d) The representations and warranties of the Loan Parties contained in each of the Loan Documents shall be true and correct on the date of such Loan or L/C;

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(e) RZB's continuing review of and continuing satisfaction with the business, operations, prospects, properties, and condition, financial or otherwise, of each of the Loan Parties;

(f) RZB shall have received (i) a copy of all corporate and partnership action, as the case may be, taken by each of the Loan Parties to authorize the execution and delivery of the agreements, instruments and documents pursuant hereto or in connection herewith, and (ii) if requested by RZB, a legal opinion of counsel to the Loan Parties, together with such opinions of special counsel to the Loan Parties as RZB shall request, and each such opinion shall be satisfactory in form and substance to RZB;

(g) RZB shall have received the unlimited personal guarantee by Mr. Jerome Richter of payment of the obligations of the Borrower, in form and substance satisfactory to RZB, and the personal financial statement of Mr. Richter in form and substance satisfactory to RZB;

(h) RZB shall have received the unlimited guarantees by each of RVEP and the Operating Partnership of payment of the obligations of the Borrower, in form and substance satisfactory to RZB;

(i) (A) Each of the Loan Parties shall have executed and delivered to RZB a general security agreement granting RZB a first priority perfected lien on the Collateral (as defined therein) in form and substance satisfactory to RZB; and

(B) RZB shall have obtained from the Loan Parties duly executed Security Agreement Questionnaires and such lien search reports as RZB shall request, all to be in form and substance satisfactory to RZB; and

(C) RZB shall have filed such UCC financing statements with respect to the Loan Parties in such jurisdictions as RZB shall request;

(j) (A) The Borrower and the Operating Partnership shall have executed and delivered to RZB amendments or supplements to the existing Mortgages, Deeds of Trust and Security Agreements previously executed by the Borrower, which shall be in form and substance satisfactory to RZB, granting RZB a first priority mortgage lien and deed of trust on the collateral described therein, including without limitation, the terminal in Brownsville, Texas and all pipelines and evidencing the assumption thereof by the Operating Partnership; and

(B) Such amendments or supplements shall have been duly filed and recorded in all filing offices deemed necessary by RZB;

(k) The Loan Parties shall have executed and/or delivered such agreements, instruments and documents, including, without limitation, consents of third parties and lessor, titles insurance policy endorsements and searches and surveys, as RZB shall request in connection with the Security Agreements and amendments or supplements referred to in the two preceding paragraphs (i) and (j);

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(l) The Operating Partnership shall have delivered to RZB copies of notices to its account debtors (including without limitation PMI Trading Limited and its affiliates), duly executed by such account debtors, directing that payment be made directly to RZB;

(m) The Loan Parties shall have delivered such evidence of insurance and loss payable endorsements as RZB may require;

(n) The Loan Parties shall have delivered copies of all of their supply and sales contracts having a term exceeding 30 days, certified as true and complete by a senior officer;

(o) The Loan Parties shall have instituted lockbox arrangements satisfactory to RZB in its sole discretion;

(p) The Borrower shall have delivered to RZB copies, certified as true and complete, of all agreements, instruments and documents, including, without limitation, all registrations and filings with and notices to the SEC and any other governmental authority, relating to the establishment, capitalization, operation, administration and management of the Loan Parties and their affiliates and the transfer by the Borrower of any or all of its assets and business to any Loan Party or affiliate thereof, and all of the foregoing shall be satisfactory in form and substance to RZB;

(q) All legal matters incident to such Loan or L/C shall be reasonably satisfactory to counsel to RZB.

7. As long as any of the Loans or L/C's or any other obligations hereunder shall be outstanding, the Borrower shall comply with the following covenants, provided that until RZB notifies the Borrower in writing, the covenants shall not apply to RVEP or the Operating Partnership:

(a) Furnish to RZB within 120 days after the end of each fiscal year a copy of the audited financial statements of the Borrower and RVEP prepared in conformity with generally accepted accounting principles consistently applied and certified without qualification by the relevant Loan Party's independent public accountants.

(b) Furnish to RZB, each certified as true and complete in all respects by the Borrower's chief financial officer or the person acting in such capacity, (i) on a quarterly basis not later than 60 days after the end of each quarter, a copy of the financial statements of each Loan Party for the preceding quarter; (ii) on a weekly basis or more frequently if required by RZB, each Loan Party's current inventory report, and on a daily basis, each Loan Party's loading rack tickets evidencing delivery of the commodity and resulting accounts receivable which are the subject of any underlying financing; and (iii) on a monthly basis not later than 30 days after the end of each month, a profit and loss statement of each Loan Party.

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(c) Furnish, to RZB such other information concerning each Loan Party's business, properties, condition or operations, financial or otherwise, as RZB may from time to time reasonably request and copies of all reports filed with the Securities and Exchange Commission from time to time.

(d) Maintain and preserve, and cause each other Loan Party to maintain and preserve, its corporate existence, and remain in the same lines of business as on the date hereof.

(e) Except as set forth on Schedule 7(e) hereto, the Borrower shall not, and shall cause each other Loan Party not to, create, assume or permit to exist any lien, security interest, mortgage, charge or other encumbrance of any nature whatsoever on any of its properties or assets, whether now owned or hereafter acquired, except in favor of RZB.

(f) The Borrower shall cause Rio Vista on a consolidated basis and the Operating Partnership to maintain an excess of total assets over total liabilities as determined in accordance with generally accepted accounting principles of at least $9,000,000 at all times.

(g) The Borrower shall not, and shall cause each Loan Party not to, declare or make at any time any dividend payment or other distribution of assets, properties, cash, rights, obligations or securities on account of any shares of any class of capital stock of the Borrower or such Loan Party, as the case may be, or its partnership interests or other equity, or purchase, redeem or otherwise acquire for value (or permit any of its subsidiaries to do so) any shares of any class of capital stock or the partnership interests or other equity of the Borrower or such other Loan Party, as the case may be, or any warrants, rights or options to acquire such shares, partnership interests or other equity now or hereafter outstanding, without the prior written consent of RZB unless, before and after giving effect to the payment of any such dividends or distributions, such Loan Party shall be in compliance with all obligations and covenants contained in this agreement and the other Loan Documents and no Default or Event of Default shall have occurred and be continuing. The Borrower shall deliver to RZB a certificate from the Borrower's chief financial officer or the person acting in such capacity on the earlier of the date of each delivery of the quarterly financial statements under Section 7(b) hereof and the date such quarterly financial statements are required to be delivered, setting forth the amount of all dividends and distributions paid by each Loan Party during the immediately preceding fiscal quarter, together with a calculation with respect thereto showing compliance with the covenant in this Section 7(g).

8. Notwithstanding anything to the contrary contained herein or in any other Loan Document, including without limitation the General Security Agreement dated October 17, 1997 between the Borrower and RZB and the General Security Agreement between the Operating Partnership and RZB:

(a) Provided that no Event of Default under any Loan Document shall have occurred and be continuing, no event that with the giving of notice or lapse of time or both would constitute such an Event of Default shall have occurred and be continuing and no demand for payment of any obligations of the Borrower shall have been made by RZB, RZB shall, upon

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request of the Borrower, execute and deliver an agreement reasonably satisfactory to RZB subordinating RZB's mortgage lien and security interest on the land, buildings and fixtures (but no other assets contained thereon or therein) constituting (x) the Borrower's terminal in Brownsville, Texas and (y) the Borrower's pipeline, to any mortgage lien and security interest of a third party unaffiliated with the Borrower (the "New Lender") which secures financing provided by the New Lender to the Borrower after the date hereof. Such agreement shall contain a covenant by the New Lender to transport at no cost to RZB from such terminal and/or through such pipeline all inventory of the Borrower or the Operating Partnership financed by RZB. The foregoing is not a consent by RZB to any additional financing or indebtedness of the Borrower.

(b) In the event the Borrower intends to obtain additional financing or incur additional indebtedness, the Borrower shall notify RZB and request RZB's consent. RZB agrees to consider such request, but the Borrower expressly acknowledges and agrees that: (x) RZB shall have sole discretion to grant or deny such consent or impose conditions on the grant of such consent and
(y) RZB has not committed or agreed to grant such consent, and such consent shall be effective only if in writing and executed by RZB.

9. The Borrower represents and warrants to RZB and covenants and agrees with RZB that, with respect to each account receivable of the Borrower and any other Loan Party financed by RZB pursuant hereto, there is not nor will there be at any time, any counterclaim, dispute or any other matter or circumstance whatsoever which could give rise to a right of set-off or other adverse claim that could be asserted by the account debtor to reduce its obligation to pay under such account receivable.

10. The Borrower represents and warrants to RZB and covenants and agrees with RZB that the business of RVEP is and shall be solely to be a holding company whose sole assets are and shall be its interests in the Operating Partnership.

11. (a) No delay on the part of RZB in exercising any of its options, powers or rights, or partial or single exercise thereof, irrespective of any course of dealing, shall constitute a waiver thereof. The options, powers and rights of RZB specified in the Loan Documents (as hereinafter defined in Section 11(c)) are in addition to those otherwise created by law or under any other agreement between any Loan Party and RZB. No amendment, modification or waiver of any provision of any Loan Document to which any Loan Party is a party, nor consent to any departure by any Loan Party therefrom, shall be effective, unless the same shall be in writing and signed by RZB. Any such waiver or consent shall be effective only in the specific instance and for the purpose for which given. No consent to or demand on any Loan Party in any case shall, of itself, entitle it to any other or further notice or demand in similar or other circumstances.

(b) This Agreement and the other Loan Documents embody the entire agreement and understanding between RZB and Loan Parties and supersede all prior agreements and understandings relating to the subject matter hereof.
THIS WRITTEN AGREEMENT (AND THE OTHER LOAN DOCUMENTS) REPRESENTS THE FINAL AGREEMENT AMONG THE PARTIES HERETO AND THE OTHER LOAN PARTIES WITH RESPECT TO

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THE MATTERS COVERED HEREBY AND THEREBY AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.

(c) The Borrower agrees to pay all costs and expenses incurred or payable by RZB and the Participant in connection with the preparation, administration, interpretation, enforcement or collection of this Agreement, the Note, any Participation Agreement between RZB and the Participant (as amended from time to time, the "Participation Agreement"), the L/C's and any applications or other agreements pertaining to the issuance thereof, the security agreements with and guarantees from the Loan Parties, the mortgages, and amendments and supplements referred to herein, and all other documents executed and delivered in connection herewith or therewith (such agreements and documents, including all amendments, modifications and supplements of or to all such agreements and documents are herein referred to as the "Loan Documents"), including, without limitation, costs of examination and audit of the Loan Parties' books and records and of the collateral security for the Loans and L/C reimbursement obligations, and court costs and reasonable attorneys' fees and disbursements.

(d) (i) If RZB or the Participant shall have determined that the applicability of any law, rule, regulation or guideline (domestic or foreign) adopted (whether before or after the date hereof) pursuant to or arising out of the July 1988 report of the Basle Committee on Banking Regulations and Supervisory Practices entitled "International Convergence of Capital Measurement and Capital Standards", or the adoption after the date hereof of any other law, rule, regulation or guideline (domestic or foreign) regarding capital adequacy, or any change in any of the foregoing or in the enforcement or interpretation or administration of any of the foregoing by any court or any governmental authority, central bank or comparable agency charged with the enforcement or interpretation or administration thereof, or compliance by RZB or the Participant or any corporation or other entity which directly or indirectly controls RZB or the Participant (each such corporation or other entity is hereinafter referred to as a "Controlling Person") (or any lending office of RZB or the Participant or any Controlling Person), with any request or directive regarding capital adequacy (whether or not having the force of law) of any such court, authority, central bank or comparable agency, has or would have the effect of reducing the rate of return on RZB's or the Participant's (as the case may be) capital or on the capital of a Controlling Person, if any, as a consequence of its issuance or maintenance of any L/C or its obligations (if any) under this Agreement or the Participation Agreement to a level below that which RZB or the Participant or such Controlling Person could have achieved but for such applicability, adoption, change or compliance (taking into consideration RZB's or the Participant's (as the case may be) policies and the policies of such Controlling Person with respect to capital adequacy) by an amount deemed by RZB or the Participant to be material, then, upon demand by RZB

or the Participant, the Borrower shall pay to RZB from time to time as specified by RZB or the Participant such additional amount or amounts as will compensate RZB or the Participant or such Controlling Person for any such reduction suffered. Any such amount paid to RZB relating to the Participant or a Controlling Person of the Participant shall be promptly paid by RZB to the Participant pursuant to the Participation Agreement between them.

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(ii) If any change in law, rule, regulation or guideline (domestic or foreign) or in the enforcement, interpretation or administration thereof by any court or any governmental authority, central bank or comparable agency charged with the interpretation or administration thereof shall at any time (A) impose, modify or deem applicable any reserve, special deposit or similar requirement (including, without limitation, pursuant to Regulation D of the Board of Governors of the Federal Reserve System) against letters of credit issued by RZB or participations therein purchased by the Participant or (B) subject letters of credit issued by RZB or participations therein purchased by the Participant to any assessment or other cost imposed by the Federal Deposit Insurance Corporation or any successor thereto or (C) impose on RZB or the Participant any other or similar condition regarding this Agreement or any L/C or the Participation Agreement, the obligations (if any) of RZB hereunder or the obligations of the Participant under the Participation Agreement and the result of any event referred to in clause (A), (B) or (C) above shall be to increase the cost to RZB or the Participant of agreeing to issue, issuing or maintaining or confirming any L/C or making, funding or maintaining (or agreeing to fund or maintain) drawings under any L/C or of participating in any L/C or to reduce any accounts receivable by RZB or the Participant hereunder or by the Participant under the Participation Agreement by an amount which RZB or the Participant shall deem to be material (which increase in cost or reduction shall be the result of the reasonable allocation by RZB or the Participant of the aggregate of such cost increases or reductions resulting from such events), then, upon

demand by RZB or the Participant, the Borrower shall pay to RZB from time to time as specified by RZB or the Participant (as the case may be), such additional amount or amounts as will compensate RZB or the Participant (as the case may be) for such increased cost from the date of such change. Any such amount paid to RZB relating to the Participant shall be promptly paid by RZB to the Participant pursuant to the Participation Agreement between them. The Borrower's obligation to pay compensation contained in this subsection (ii) shall be applicable as well to any amount RZB may be obligated to pay any financial institution which confirms or advises any L/C and which incurs or is subjected to any increased cost or reduction of amounts receivable as a result of the imposition, modification or applicability of any such reserve, special deposit or similar requirement, the subjecting of L/C's to any such assessment or other cost, or the imposition of any such other or similar condition.

(iii) The provisions of this subsection (d) shall survive the termination of this Agreement.

(iv) RZB or the Participant shall notify the Borrower within 3 months after it becomes aware of its right to claim any amount under paragraphs (d)(i) or (ii) above, provided that (A) if such lender fails to so notify the Borrower within such 3 month period, such lender shall not be entitled to claim any additional amounts pursuant to this subsection for any period ending on a date which is prior to 3 months before such notification plus any additional period of retroactive effect of the law, rule, regulation or guideline referred to in paragraph (d)(i) or (ii) above, and (B) neither RZB nor the Participant shall have any right to assert a claim for any amount under paragraphs (d)(i) or (ii) after the date which is 3 months after payment in full of all Loans, obligations in respect of L/C's and other obligations hereunder and the termination of this Agreement.

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(e) The Loan Documents to which the Borrower and the Loan Parties are a party shall be binding on the Borrower and the Loan Parties and their respective successors and assigns, and shall inure to the benefit of RZB and its successors and assigns, provided that the Borrower shall not have the right to assign its rights hereunder or thereunder or any interest herein or therein without RZB's prior written consent.

(f) In addition to the rights granted to it by applicable law, RZB has the right to set-off and apply to any of the Borrower's and Loan Parties obligations hereunder and under the Loan Documents any amount received by it for the Borrower or any of the Loan Parties. The Participant shall have a right of set-off and banker's lien to the same extent as if its participation under the Participation Agreement were a direct loan to the Borrower.

(g) THIS AGREEMENT SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE STATE OF NEW YORK (WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW).

CONTRARY TO THE EXPRESS AGREEMENT OF THE PARTIES IN THIS
SECTION 11(G) HEREOF, IF THE LAWS OF ANY STATE OTHER THAN NEW YORK, INCLUDING THE LAWS OF THE STATE OF TEXAS, SHALL BE DETERMINED TO BE APPLICABLE TO THIS AGREEMENT, THE NOTE OR THE OTHER LOAN DOCUMENTS, IT IS THE INTENT OF THE PARTIES HERETO TO COMPLY WITH ALL APPLICABLE USURY LAWS AND TO LIMIT ALL INTEREST CONTRACTED FOR, RESERVED, CHARGED OR RECEIVED UNDER THE LOAN DOCUMENTS TO THE MAXIMUM NONUSURIOUS RATE OF INTEREST PERMITTED BY APPLICABLE LAW. IF THE APPLICABLE COMMON LAW AND PRINCIPLES OF EQUITY AND CONSTITUTIONS, STATUTES, RULES, REGULATIONS AND ORDERS OF GOVERNMENTAL BODIES AND AUTHORITIES, AND ORDERS, WRITS, DECISIONS, INJUNCTIONS AND DECREES OF ALL COURTS, ARBITRATORS AND GOVERNMENTAL INSTRUMENTALITIES (THE "APPLICABLE LAW") IS EVER JUDICIALLY INTERPRETED SO AS TO RENDER USURIOUS ANY AMOUNT CALLED FOR UNDER OR IN CONNECTION WITH THE NOTES, THIS AGREEMENT AND THE LOAN DOCUMENTS, OR CONTRACTED FOR, CHARGED, TAKEN, RESERVED OR RECEIVED WITH RESPECT TO THE TRANSACTIONS REFERRED TO HEREIN OR THEREIN, OR IF DEMAND OF OR ACCELERATION OF THE MATURITY OF THE NOTE OR IF ANY PREPAYMENT BY BORROWER OR ANY OF THE LOAN PARTIES RESULTS IN BORROWER OR LOAN PARTIES OR ANY OTHER PERSON HAVING PAID ANY INTEREST (HOWEVER DENOMINATED) IN EXCESS OF THAT PERMITTED BY LAW FOR THE ACTUAL PERIOD THE NOTE AND THE OBLIGATIONS OF THE BORROWER AND THE LOAN PARTIES ARE OUTSTANDING, THEN IT IS THE BORROWER'S, THE LOAN PARTIES' AND RZB'S INTENT THAT ALL EXCESS AMOUNTS THERETOFORE RECEIVED BY RZB SHALL BE CREDITED ON THE PRINCIPAL BALANCE OF THE NOTE (OR, IF THE NOTE HAS BEEN OR WOULD THEREBY BE PAID IN FULL, REFUNDED TO THE BORROWER OR THE LOAN PARTIES), AND THE PROVISIONS OF THE NOTE AND THIS AGREEMENT IMMEDIATELY SHALL BE DEEMED REFORMED AND THE AMOUNTS THEREAFTER COLLECTIBLE UNDER THE NOTE, THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS REDUCED, WITHOUT THE NECESSITY OF THE EXECUTION OF ANY NEW DOCUMENTS, SO AS TO COMPLY WITH THE APPLICABLE LAW, BUT SO AS TO PERMIT THE RECOVERY OF THE FULLEST AMOUNT OTHERWISE CALLED FOR UNDER THE NOTE, THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS FOR THE ACTUAL PERIOD THE NOTE AND OTHER OBLIGATIONS OF THE BORROWER AND THE LOAN PARTIES ARE OUTSTANDING.

(h) THE BORROWER AND THE LOAN PARTIES HEREBY AGREE THAT ANY LEGAL ACTION OR PROCEEDING AGAINST THE BORROWER OR ANY LOAN PARTY WITH RESPECT TO THIS AGREEMENT OR ANY OTHER LOAN DOCUMENT MAY BE BROUGHT IN THE COURTS OF THE STATE OF NEW YORK

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IN THE CITY OF NEW YORK OR OF THE UNITED STATES OF AMERICA FOR THE SOUTHERN DISTRICT OF NEW YORK AS RZB MAY ELECT, AND, BY EXECUTION AND DELIVERY HEREOF, EACH OF THE BORROWER AND THE LOAN PARTIES ACCEPT AND CONSENT TO, FOR ITSELF AND IN RESPECT TO ITS PROPERTY, GENERALLY AND UNCONDITIONALLY, THE JURISDICTION OF THE AFORESAID COURTS AND AGREES THAT SUCH JURISDICTION SHALL BE EXCLUSIVE, UNLESS WAIVED BY RZB IN WRITING, WITH RESPECT TO ANY ACTION, CLAIM OR PROCEEDING BROUGHT BY IT AGAINST RZB AND ANY QUESTIONS RELATING TO USURY. NOTHING HEREIN SHALL LIMIT THE RIGHT OF RZB TO BRING PROCEEDINGS AGAINST THE BORROWER AND THE LOAN PARTIES IN THE COURTS OF ANY OTHER JURISDICTION. THE BORROWER AND THE LOAN PARTIES AGREE THAT SECTIONS 5-1401 AND 5-1402 OF THE GENERAL OBLIGATIONS LAW OF THE STATE OF NEW YORK SHALL APPLY TO THIS AGREEMENT AND, TO THE MAXIMUM EXTENT PERMITTED BY LAW, WAIVES ANY RIGHT TO STAY OR TO DISMISS ANY ACTION OR PROCEEDING BROUGHT BEFORE SAID COURTS ON THE BASIS OF FORUM NON CONVENIENS.

(i) AFTER REVIEWING THIS PROVISION SPECIFICALLY WITH ITS RESPECTIVE COUNSEL, EACH OF THE BORROWER, THE LOAN PARTIES AND RZB HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVES ANY AND ALL RIGHTS IT MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION BASED ON, OR ARISING OUT OF, UNDER, OR IN CONNECTION WITH, THIS AGREEMENT OR ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER VERBAL OR WRITTEN), OR ACTIONS OF THE BORROWER, THE LOAN PARTIES OR RZB. THIS PROVISION IS A MATERIAL INDUCEMENT FOR RZB MAKING THE LOANS TO THE BORROWER AND THE LOAN PARTIES.

(j) NO CLAIM MAY BE MADE BY THE BORROWER OR ANY LOAN PARTY OR ANY OTHER PERSON AGAINST RZB OR THE PARTICIPANT OR THE OFFICERS, DIRECTORS, EMPLOYEES OR AGENTS OF RZB OR THE PARTICIPANT FOR ANY SPECIAL, INDIRECT, PUNITIVE OR CONSEQUENTIAL DAMAGES IN RESPECT OF ANY CLAIM FOR BREACH OF CONTRACT OR ANY OTHER THEORY OF LIABILITY ARISING OUT OF OR RELATED TO THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT, ANY OBLIGATIONS OF THE BORROWER OR ANY LOAN PARTY AND/OR ANY OF THE COLLATERAL, OR ANY ACT, OMISSION OR EVENT OCCURRING IN CONNECTION THEREWITH, AND THE BORROWER AND EACH LOAN PARTY HEREBY WAIVES, RELEASES AND AGREES NOT TO SUE UPON ANY CLAIM FOR ANY SUCH DAMAGES.

(k) Notwithstanding the Participation Agreement, the Borrower shall be permitted, except as otherwise expressly provided herein,