Document:

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                                                                   EXHIBIT 10.50

               (English Translation of Original Spanish Document)

Modifying Agreement to the Supply Agreement between The Coca Cola Export
Corporation (COEXPORT) and GRUPO INDUSTRIAL SANTA ENGRACIA S.A. de C.V.
represented by Jose Maria Martinez Brohez (the "GROWER")

DECLARATIONS

Both Parties declare:

        1.      On April 2 1998, a supply agreement (the "Agreement") was signed
                in which the GROWER, among other thing agreed to destine an area
                of 3500 hectares, on land of its property, for the purpose of
                growing Italian Lemon and the subsequent selling of its crop to
                COEXPORT,

        2.      That the Agreement has been executed with delay, because of
                financial problems by the GROWER,

        3.      That the parties agree to reduce the area as well as the number
                of trees destined for the growing of Italian Lemon and want to
                celebrate the Modifying Agreement, and

        4.      That the parties want to reaffirm the "intuit personae"
                character of the initial Agreement and they want to ratify this
                by adding a new paragraph to the twelve clause of the Agreement.

Therefore, both parties agree to the following:

                                    CLAUSES

ONE - Parties agree to reduce the amount of hectares destined for the planting
of Italian Lemon by 500 hectares, which subtracted from the original 3,500
hectares stated in the AGREEMENT, result in 3,000 hectares (three thousand
hectares)

Parties agree to modify Declaration I B, Clauses One, Second and Nine and any
other references to the 3,500 hectares or the number of trees destined for the
growing of Italian Lemon, so that they read 3,000 hectares and 750,000 tress.

SECOND- Clause TWELVE of the Agreement is modified to read as follows -

        " TWELVE - none of the parties can cede its rights and contractual
        obligations without the prior written consent of the other party.
        Anything not contemplated in the AGREEMNT will be guided by the Federal
        District Civil Law".

THIRD - All other clauses of this Agreement remain unchanged and in force as
long as they do not oppose this agreement, until the date of the termination.

This contract is signed in Ciudad Victoria, Tamaulipas on January 15, 2001.

For COEXPORT                                        FOR The GROWER

By: Eduardo Arrocha Gio                             By: Jose Ma. Martinez Brohez

Testigo:                                            Testigo:

By: Eduardo Zago Berra                              By: Manuel Martinez Arteaga<PAGE>
                                                                   EXHIBIT 10.11

                              WAIVER AND AMENDMENT

         THIS WAIVER AND AMENDMENT ("Waiver"), dated effective as of December
11, 2001, is made by and between VENUS EXPLORATION, INC. (the "Borrower"), and
HIBERNIA NATIONAL BANK (the "Lender"), who agree as follows:

                                    RECITALS

         A. Borrower and Lender have heretofore executed a Loan Agreement dated
as of July 6, 2001 (the "Loan Agreement").

         B. The Borrower has requested that the Lender waive a financial
covenant for the period ending September 30, 2001.

         C. The Lender is willing to accept the Borrower's request on the terms
and conditions set forth below.

         D. Capitalized terms used herein, and not otherwise defined herein,
shall have the meanings defined in the Loan Agreement.

                                    AGREEMENT

         NOW, THEREFORE, in consideration of the mutual covenants and
undertakings, the parties hereby agree as follows:

                                    ARTICLE 1
                                     WAIVER

         1.1 The Borrower has advised the Lender that notwithstanding the
provisions of Section 5.15(b) of the Loan Agreement, requiring a minimum net
worth for the fiscal quarter ended September 30, 2001, to be not less than
$1,866,600.00, in fact the Borrower's net worth was less than that requirement.
At the Borrower's request, Lender hereby grants a one-time waiver of the minimum
net worth covenant for the fiscal quarter ended September 30, 2001. Such waiver
shall not constitute either an amendment of the Loan Agreement or a precedent
for any subsequent requested waiver of this or any other financial covenant or
other provision of the Loan Agreement. Without limiting the preceding sentence,
the Borrower specifically acknowledges that the minimum net worth requirement
for the fiscal quarter to end December 31, 2001, is not waived by the Lender.

                                    ARTICLE 2
                                     AMOUNT

         2.1 In consideration of the granting of the waiver set forth above, the
Borrower and the Lender agree that the definition of "Amount" in Loan Agreement
Section 1.2 is hereby amended and restated to read in its entirety as follows:

                  "Amount" shall mean one million nine hundred thousand
                  ($1,900,000.00) dollars.

         2.2 In further consideration of the granting of the waiver set forth
above, and notwithstanding any provisions of the Loan Agreement or the Note (or
the Letter Agreement dated July 9, 2001) to the contrary,

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the Borrowing Base shall be limited to an amount not to exceed one million nine
hundred thousand ($1,900,000.00) dollars. As provided in Loan Agreement
Subsection 2.4(c), this Borrowing Base amount shall be subject to the automatic
Monthly Borrowing Base Reductions commencing on December 31, 2001, and
continuing on the last day of each successive month. In addition, as provided in
the Loan Agreement the Borrowing Base may be further revised by Lender in its
sole discretion from time to time. Without limiting the foregoing, the Borrower
acknowledges that the Lender may consider the status of the Borrower's accounts
payable, the title opinions submitted to the Lender, and all of the other facts
and matters set forth in a definition of "Borrower Base" in the Loan Agreement.

                                    ARTICLE 3
                                 FINANCIAL TERMS

         3.1 In further consideration of the granting of the waiver set forth
above, and notwithstanding any provisions of the Loan Agreement or the Note to
the contrary, the Borrower and Lender agree that from and after the effective
date of this Waiver (i) all new Advances shall be Base Rate Advances, (ii) all
existing LIBO Rate Advances (if any) shall immediately convert to Base Rate
Advances, and (iii) all Base Rate Advances (i.e., the entire Loan) shall bear
interest at a rate per annum equal to the Prime Rate in effect from time to time
plus two (2.0%) percent per annum (the Base Rate equaling the Prime Rate plus
2.0 %).

         3.2 In further consideration of the granting of the waiver set forth
above, the Borrower shall pay the Lender a waiver fee in the amount equal to
$12,500.00 immediately upon execution of this Waiver by the Lender.

                                    ARTICLE 4
                                 MONTHLY REPORTS

         4.1 In further consideration of the granting of the waiver set forth
above, and notwithstanding the provisions of Section 5.2 of the Loan Agreement,
the Borrower and the Lender agree that the Borrower shall furnish to the Lender
(i) promptly upon request from time to time, a written explanation and
description of all unpaid royalty amounts and other payables currently due, (ii)
within 45 days after the end of the 2001 fiscal year, and each fiscal year
thereafter, the unaudited financial statements (balance sheet, statement of
income, statement of reconciliation of capital accounts, and statement of cash
flow) of Borrower for such fiscal year, certified by the principal financial
officer of the Borrower, and (iii) within 15 days after the end of each month,
an accounts payable aging report and an accounts receivables aging report for
the Borrower as of the end of each month, each in form and substance
satisfactory to the Lender.

                                    ARTICLE 5
                                DOMINION ACCOUNT

         5.1 In further consideration of the granting of the waiver set forth
above, the Borrower agrees that the revenue distribution account maintained at
the Lender pursuant to Loan Agreement Section 5.17 shall be subject to the
dominion and control of the Lender. All payments for mineral production due to
the Borrower from its properties (whether or not such properties are Collateral)
shall be paid directly to the Lender into such revenue distribution account at
all times. The Borrower represents and warrants to the Lender (which
representation and warranty will survive the execution of this Waiver) that in
compliance with Loan Agreement Section 5.17 the Borrower has instructed all of
its existing customers to send all payments for mineral production due to the
Borrower from its properties directly to the Lender either to the lockbox
account or by direct wire transfer into the revenue distribution account.
Independent of (and without

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limiting) Borrower's obligation to provide such payment instructions, the
Borrower agrees to immediately deposit in such revenue distribution account,
daily, all amounts received by Borrower on any accounts and sales of
hydrocarbons. All such deposits shall be made no later than the first Business
Day after collection by the Borrower. Notwithstanding any provisions of the Loan
Agreement to the contrary (including without limitation Section 5.17), the
Borrower shall have no right to draw upon the revenue distribution account.
Instead, the Borrower authorizes the Lender to apply, on each Business Day, the
proceeds actually collected (or, at the sole discretion of the Lender, amounts
which have been received but not yet collected) by the Lender in the revenue
distribution account, to reduce the outstanding principal balance of the Loan.

         5.2 The Borrower acknowledges that no disbursements from the revenue
distribution account shall be made to the Borrower. Instead, the Borrower shall
establish and maintain one or more deposit accounts with the Lender for checks
drawn by the Borrower or wire transfer payments requested by the Borrower.
Payments by the Lender of checks drawn by the Borrower, or wire transfer
payments requested by the Borrower, shall be made by the Lender pursuant to an
Advance under the Loan in accordance with the provisions of the Loan Agreement.

                                    ARTICLE 6
                                   CORRECTION

         6.1 The reference in the penultimate sentence of Credit Agreement
Section 2.1(f) to the "Commitment Amount" is hereby corrected and amended to be
"Commitment Limit".

                                    ARTICLE 7
                          ACKNOWLEDGMENT OF COLLATERAL

         7.1 Borrower hereby specifically reaffirms all of the Collateral
Documents.

                                    ARTICLE 8
                                  MISCELLANEOUS

         8.1 The Borrower represents and warrants to the Lender (which
representations and warranties will survive the execution of this Waiver) that
(i) all representations and warranties contained in the Loan Agreement and the
Collateral Documents are true and correct on and as of the date hereof as though
made on and as of such date, (ii) no event has occurred and is continuing as of
the date hereof which constitutes a Default or Event of Default (taking into
account the specific waiver set forth in paragraph 1.1 in this Waiver), and
(iii) there is no defense, offset, compensation, counterclaim or reconventional
demand with respect to amounts due under, or performance of, the terms of the
Note. To the extent any such defense, offset, compensation, counterclaim or
reconventional demand or other causes of action by the Borrower against the
Lender might exist, whether known or unknown, such items are hereby waived by
the Borrower.

         8.2 Borrower hereby and forever settles, compromises, transacts,
satisfies, waives, releases, acquits, discharges, surrenders and cancels any and
all Claims (as defined hereinafter) against the Lender, its insurers or
insureds, subrogors or subrogees, assignors or assignees, nominees,
representatives, joint venturers, directors, officers, agents, employees,
attorneys, shareholders, principals, parent companies, subsidiary companies,
other affiliates, and any other person or entity which has or might have
derivative, secondary or vicarious liability for their acts or omissions whose
rights are derived from them (all of such released parties being collectively
referred to as the "Released Parties"), it being hereby specifically agreed and
understood that the execution of this Waiver is not to be construed as an
acknowledgment or admission

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of any fact of any liability or responsibility by the Lender, and the Lender
hereby expressly denies any liability to the Borrower. For the purpose of this
Agreement, "Claims" shall mean (i) any and all claims, demands, losses, damages,
causes of action, and rights of action whatsoever, liquidated or unliquidated,
choate or inchoate, matured or unmatured, contingent or exigible, asserted or
unasserted, direct or indirect, known or unknown, anticipated or unanticipated,
arising before or on the date of the Borrower's execution hereof whether based
upon tort, negligence, intentional conduct, contract, equity, bankruptcy,
indemnity, contribution, reimbursement, unjust enrichment, and/or any other
legal theory, which any party may be entitled to in any way, and (ii) arising
out of or relating to the Loan Agreement, the Note and the Collateral Documents
from time to time executed in connection therewith (collectively the "Loan
Documents"), but (iii) excluding any Claims (as defined in preceding clauses (i)
and (ii)) against the Released Parties based upon fraudulent or dishonest acts
of the Lender, and Claims to require the Released Parties to perform any
contractual undertakings under the Loan Documents.

         8.3 Subject to the specific waiver set forth in paragraph 1.1 of this
Waiver and the provisions contained in this Waiver, all terms and provisions of
the Loan Agreement and Note are hereby ratified and confirmed, and shall be and
shall remain in full force and effect, enforceable in accordance with their
terms.

         8.4. THIS WAIVER IS A CONTRACT MADE UNDER AND SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE UNITED STATES OF AMERICA AND THE
STATE OF LOUISIANA.

         8.5 This Waiver may be executed in any number of separate counterparts,
and all of said counterparts taken together shall be deemed to constitute one in
the same instrument.

         IN WITNESS WHEREOF, the parties hereto have caused this Waiver to be
duly executed as of the date first above written.

BORROWER:                                   VENUS EXPLORATION, INC.

                                            By:
                                                --------------------------------
                                                Name:
                                                Title:

LENDER:                                     HIBERNIA NATIONAL BANK

                                            By:
                                                --------------------------------
                                                Name:
                                                Title:

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