EXHIBIT 10.4
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                               GUARANTY AGREEMENT


         THIS GUARANTY AGREEMENT (this "Agreement") made and entered into
effective as of the 29th day of July, 2005, by ENDEAVOR PIPELINE INC., an
Oklahoma corporation (the "Guarantor") in favor of HIBERNIA NATIONAL BANK (the
"Lender"), guaranteeing the Secured Liabilities (as hereinafter defined) of GMX
RESOURCES INC., an Oklahoma corporation (the "Borrower").


                              W I T N E S S E T H:


         FOR VALUE RECEIVED, and in consideration of and for credit and
financial accommodations extended, to be extended, or continued to or for the
account of the above named Borrower, the undersigned Guarantor hereby agrees as
follows:

         SECTION 1. Guaranty of Borrower's Secured Liabilities.

         (a) Each Guarantor does hereby irrevocably, absolutely and
unconditionally guarantee for the benefit of the Lender the prompt and punctual
payment of all of the following items of indebtedness (collectively the "Secured
Liabilities") (capitalized terms used below in the description of the Secured
Liabilities have the meanings set forth in the definitions in paragraph (b)
below), as and when the same shall be due and payable, whether by passage of
time, acceleration of maturity or otherwise:

                    (i) All obligations of the Borrower now or hereafter
               existing under the Loan Agreement and other Loan Documents to the
               Lender, including all future advances and other future
               indebtedness under the Loan Agreement, all whether obligatory or
               discretionary, and including any extensions or renewals of all
               such indebtedness under the Loan Documents, whether or not the
               Borrower executes any extension agreement or renewal instrument,
               including without limitation: (1) all obligations, liabilities
               and indebtedness now or hereafter arising of the Borrower to the
               Lender in respect of the principal of and interest on the Note,
               the Loan, the Credit Obligations and any letters of credit issued
               under the Loan Agreement (including interest which, but for the
               filing of a petition in bankruptcy with respect to Borrower,
               would have accrued on any Secured Liabilities, whether or not a
               claim is allowed against Borrower for such interest in the
               related bankruptcy proceeding), and (2) the obligations of the
               Borrower in respect of fees and all other amounts payable by the
               Borrower to the Lender under any Loan Documents;

                    (ii) Any sums advanced or expenses or costs incurred by the
               Lender which are made or incurred pursuant to, or permitted by,
               the Collateral Documents and the Loan Agreement, plus interest
               thereon at the rate herein specified or otherwise agreed upon,
               from the date of the advances or the incurring of such expenses
               or costs until reimbursed;

                    (iii) Any increases to the Loan under the Loan Agreement
               which the Lender may from time to time make to the Borrower in
               agreement with the Borrower, the

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               Lender not being obligated, however, to make such increased
               loans, and any promissory notes evidencing the Loan (recognizing
               that the liability for the principal balance of the Loan is the
               aggregate unpaid principal balance of advances under the Loan and
               not necessarily the face amount of such promissory notes, which
               face amount may be larger than the actual liability); and

                    (iv) Any liabilities of the Borrower to the Lender under (x)
               transactions in futures, forwards, swaps or option contracts
               (including both physical and financial settlement transactions)
               engaged in by the Borrower as a hedge against adverse changes in
               the prices of natural gas or oil (including without limitation
               commodity price hedges, swaps, caps, floors, collars and similar
               agreements designed to protect the Borrower against fluctuations
               in commodity prices), or (y) forward contracts, futures
               contracts, swaps, option contracts or other financial agreements
               or arrangements relating to, or the value of which is dependent
               upon, interest rates or currency exchange rates (including
               without limitation caps, floors, collars, puts and similar
               agreements designed to protect the Borrower against fluctuations
               in interest rates or currency exchange rates) in each case
               engaged in by the Borrower as a risk-management strategy.

         (b) For all purposes of this Agreement, the following terms shall have
the meanings indicated:

               "Credit Obligations" shall mean the Borrower's obligations under
               the Loan Agreement and the other Loan Documents to pay (i)
               reimbursement of any and all drafts drawn under any letter of
               credit issued under the Loan Agreement, (ii) any and all costs,
               charges, fees and/or expenses incurred or paid by the Lender in
               connection with any such letter of credit issued under the Loan
               Agreement, (iii) any and all charges of the Lender arising out of
               the imposition of or change in any reserve or capitalization
               requirement with respect to letters of credit effective after the
               date of the Loan Agreement, and (iv) interest on such amounts
               described above under (i), (ii) and (iii) as provided in the Loan
               Agreement (including interest which, but for the filing of a
               petition in bankruptcy with respect to Borrower, would have
               accrued on any Secured Liabilities, whether or not a claim is
               allowed against Borrower for such interest in the related
               bankruptcy proceeding).

               "Loan Agreement" shall mean that certain Loan Agreement dated as
               of July 29 , 2005, between the Borrower and the Lender, as such
               agreement may hereafter be amended, renewed, extended, increased
               or replaced.

               "Loan Documents" shall mean the Loan Agreement, the Note, the
               Mortgage and any other Collateral Documents (as defined in the
               Loan Agreement), and any other instrument or document executed in
               connection herewith or therewith, as any of said documents may
               from time to time be amended, supplemented, renewed or restated.

               "Mortgage" shall mean collectively each and every mortgage or
               deed of trust granted by the Borrower in favor of the Lender
               pursuant to the Loan Agreement.

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               "Note" shall mean the Line of Credit Note issued by the Borrower
               under the Loan Agreement payable to the order of the Lender, and
               shall also include any and all extensions, modifications or
               renewals from time to time of said Promissory Note.

         (c) Anything in this Agreement to the contrary notwithstanding, if any
Fraudulent Transfer Law (as hereinafter defined) is determined by a court of
competent jurisdiction to be applicable to the obligations of a Guarantor under
this Agreement, such obligations of such Guarantor hereunder shall be limited to
a maximum aggregate amount equal to the largest amount that would not render its
obligations hereunder subject to avoidance as a fraudulent transfer or
conveyance under Section 548 of Title XI of the United States Code or any
applicable provisions of comparable state law (collectively, the "Fraudulent
Transfer Laws"), in each case after giving effect to all other liabilities of
such Guarantor, contingent or otherwise, that are relevant under the Fraudulent
Transfer Laws.

         (d) Without limiting any other provision of this Agreement, should an
Event of Default (as defined in the Loan Agreement) occur, each Guarantor
unconditionally and absolutely agrees to pay the full then unpaid amount of all
of Borrower's Secured Liabilities guaranteed hereunder. Such payment or payments
shall be made immediately following demand by Lender.

         SECTION 2. Joint and Several Liability. Each Guarantor further agrees
that its obligations and liabilities for the prompt and punctual payment,
performance and satisfaction or purchase of all of Borrower's Secured
Liabilities shall be on a "joint and several" basis with Borrower, subject to
Subsection 1(c). In the event that there is more than one guarantor under this
Agreement, or in the event that there are other guarantors, endorsers, or
sureties of all or any portion of Borrower's Secured Liabilities, each
Guarantor's obligations and liabilities hereunder shall be on a "joint and
several" basis along with such other guarantor or guarantors, endorsers and/or
sureties, subject to Subsection 1(c). The obligations of each Guarantor
contained in this Agreement shall be absolute and unconditional without regard
to the validity, legality, regularity or enforceability of the Secured
Liabilities, or any instrument evidencing, securing or relating to the Secured
Liabilities, and shall not be reduced or affected in any way by any action which
may in any manner or to any extent vary the risks of the Guarantor, or which
might otherwise constitute a legal or equitable discharge of the Guarantor. It
is the purpose and intent of the Guarantor and the Lender that this Agreement
and the obligations of the Guarantor hereunder shall be absolute and
unconditional under any and all circumstances and shall not be discharged except
by payment and performance as herein provided, and that this Agreement be
construed as a payment guaranty and not as a guaranty of collection and each
Guarantor's liability under this Agreement shall be primary, and not secondary.
Additionally, subject to Subsection 1(c), each Guarantor, in furtherance of the
foregoing and not in limitation of any other right which the Lender may have
against the Guarantor by virtue hereof, hereby guarantees jointly and severally,
absolutely and unconditionally, the payment of any and all Secured Liabilities
to the Lender whether or not due or payable by the Borrower upon the occurrence
in respect of the Borrower of any of the events specified in Subsections (g) or
(h) of Section 8.1 of the Loan Agreement (including amounts that would become
due but for the operation of the automatic stay under Section 362(a) of the
Bankruptcy Code, 11 U.S.C. 362(a)).

         SECTION 3. Duration. This Agreement and each Guarantor's obligations
and liabilities hereunder shall remain in full force and effect until such time
as all of Borrower's Secured Liabilities shall be paid, performed and/or
satisfied in full, in principal, interest, costs and attorney's fees.

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         SECTION 4. Waivers. Each Guarantor hereby waives notice of acceptance
of this Agreement and of any Secured Liabilities to which it applies or may
apply. Each Guarantor further waives presentment and demand for payment of
Borrower's Secured Liabilities, notice of dishonor and of nonpayment, notice of
intention to accelerate, notice of acceleration, protest and notice of protest,
collection or institution of any suit or other action by Lender in collection
thereof, including any notice of default in payment thereof or other notice to,
or demand for payment thereof on any party. Each Guarantor additionally waives,
to the degree applicable, any and all rights and pleas of division and
discussion as provided under Louisiana law as well as any similar rights as may
be provided under the laws of any other state. Additionally, each Guarantor also
waives joinder of Borrower or any other obligor of any of the Secured
Liabilities in any suit or action to enforce this Agreement, and in particular,
and without in any way limiting the foregoing, each Guarantor also waives any
right (including without limitation each right created by the provisions of
Chapter 34 of the Texas Business & Commerce Code, Chapter 17 of the Texas Civil
Practice and Remedies Code, the Texas Rules of Civil Procedure or any other
applicable law) to require Lender to file suit against Borrower or any such
obligor or to take any other action against Borrower or any such obligor as a
prerequisite to Lender's taking any action or bringing any suit against
Guarantor under this Agreement. Each Guarantor also waives, to the maximum
extent permitted by law, all rights, remedies, claims, defenses and benefits
based upon or related to Sections 51.003, 51.004 and 51.005 of the Texas
Property Code, as it may be amended (or any successor statute or similar law).

         SECTION 5. Guarantor's Subordination of Loans and Rights. In the event
that any Guarantor should for any reason (A) advance or lend monies to Borrower,
whether or not such funds are used by Borrower to make payment(s) under
Borrower's Secured Liabilities, and/or (B) make any payment(s) to Lender for and
on behalf of Borrower under Borrower's Secured Liabilities, and/or (C) make any
payment to Lender in total or partial satisfaction of Guarantor's obligations
and liabilities under this Agreement, the Guarantor hereby agrees that any and
all rights that Guarantor may have or acquire to collect from or to be
reimbursed by Borrower (or from or by any other guarantor, endorser or surety of
Borrower's Secured Liabilities), whether Guarantor's rights of collection or
reimbursement arise by way of subrogation to the rights of Lender or otherwise,
shall in all respects, whether or not Borrower is presently or subsequently
becomes insolvent, be subordinate, inferior and junior to the rights of Lender
to collect and enforce payment, performance and satisfaction of Borrower's then
remaining Secured Liabilities, until such time as Borrower's Secured Liabilities
are fully paid and satisfied. So long as no Event of Default as defined in the
Loan Agreement exists, the Guarantor may be repaid by Borrower as to any
subordinated debt (if any) expressly permitted by the Loan Agreement. In the
event of Borrower's insolvency or consequent liquidation of Borrower's assets,
through bankruptcy, by an assignment for the benefit of creditors, by voluntary
liquidation, or otherwise, the assets of Borrower applicable to the payment of
claims of both Lender and Guarantor shall be paid to Lender and shall be first
applied by Lender to Borrower's then remaining Secured Liabilities. The
Guarantor hereby assigns to Lender all claims which it may have or acquire
against Lender for full payment of Borrower's Secured Liabilities guaranteed
under this Agreement. If Guarantor is, or at any time may be, an "insider" of
Borrower (or of any other guarantor, surety or endorser of Borrower's Secured
Liabilities) within the context of Section 101(30) of the Bankruptcy Code (11
U.S.C. 101(30)), Guarantor shall have no rights of, and unconditionally agrees
not to seek or obtain, collection or reimbursement from Borrower (or from any
other guarantor, surety or endorser of Borrower's Secured Liabilities), whether
by subrogation of Lender's rights or otherwise until the thirteenth (13th) month
anniversary date following the full and final payment and satisfaction of
Borrower's Secured Liabilities.

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         SECTION 6. Covenants Relating to the Secured Liabilities. Each
Guarantor further agrees that Lender may, at its sole option, at any time, and
from time to time, without the consent of or notice to Guarantor or any other
party, and without incurring any responsibility to Guarantor or any other party,
and without impairing or releasing the obligations of Guarantor under this
Agreement:

         (a) Discharge or release any party (including, but not limited to,
Borrower, any Guarantor or any other co-guarantor) who is or may be liable to
Lender for any of Borrower's Secured Liabilities;

         (b) Sell, exchange, release, surrender, realize upon or otherwise deal
with, in any manner and in any order, any collateral directly or indirectly
securing repayment of any of Borrower's Secured Liabilities or the Guaranty
Agreement;

         (c) Change the manner, place or terms of payment, or change or extend
the time of payment of or renew or restate, as often and for such periods as
Lender may determine, or alter or increase, any of Borrower's Secured
Liabilities, including without limitation increases in the available principal
amount of the Borrower's line of credit or in the interest rate under the Note;

         (d) Settle or compromise any of Borrower's Secured Liabilities;

         (e) Subordinate and/or agree to subordinate the payment of all or any
part of Borrower's Secured Liabilities or Lender's security rights in and/or to
any collateral directly or indirectly securing any such Secured Liabilities, to
the payment and/or security rights of any other present and/or future creditors
of Borrower;

         (f) Apply any sums paid to any of Borrower's Secured Liabilities, with
such payments being applied in such priority or with such preferences as Lender
may determine in its sole discretion, regardless of what Secured Liabilities of
Borrower remains unpaid;

         (g) Take or accept any other security or guaranty for any or all of
Borrower's Secured Liabilities;

         (h) Make additional secured and/or unsecured loans to Borrower and/or
any other Guarantor; and/or

         (i) Enter into, deliver, modify, amend or waive compliance with, any
instrument or arrangement evidencing, securing or otherwise affecting, all or
any part of Borrower's Secured Liabilities.

         In addition, no course of dealing between Lender and Borrower (or any
other guarantor, surety or endorser of Borrower's Secured Liabilities), nor any
failure or delay on the part of the Lender to exercise any of Lender's rights
and remedies, or any other agreement or agreements by and between the Lender and
Borrower (or any other guarantor, surety or endorser) shall have the affect of
impairing or releasing Guarantor's obligations and liabilities to Lender or of
waiving any of Lender's rights and remedies. Any partial exercise of any rights
and remedies granted to Lender shall furthermore not constitute a waiver of any
of Lender's other rights and remedies, it being Guarantor's intent and agreement
that Lender's rights and remedies shall be cumulative in nature. The Guarantor
further agrees that, should Borrower default under any of Borrower's Secured
Liabilities, any waiver or forbearance on the part of Lender to pursue the
rights and remedies available to Lender's shall be

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binding upon the Lender only to the extent that Lender specifically agrees to
such waiver or forbearance in writing. A waiver or forbearance on the part of
Lender as to one event of default shall not constitute a waiver or forbearance
as to any other default.

         SECTION 7. No Release of Guarantor. Each Guarantor's obligations and
liabilities under this Agreement shall not be released, impaired, reduced or
otherwise affected by, and shall continue in full force and effect,
notwithstanding the occurrence of any event, including without limitation any
one or more of the following events:

         (a) Death, insolvency, bankruptcy, arrangement, adjustment,
composition, liquidation, disability, dissolution or lack of authority (whether
corporate, partnership or trust) of Borrower (or any person acting on Borrower's
behalf), or any other Guarantor, surety or endorser of any of Borrower's Secured
Liabilities;

         (b) Partial payment or payments of any amount due and/or outstanding
under any of Borrower's Secured Liabilities (except to the extent that any
payments by Guarantor under this Agreement or by Borrower reduce the Secured
Liabilities);

         (c) Any payment by Borrower or any other party to Lender is held to
constitute a preferential transfer or a fraudulent conveyance under any
applicable law, or for any reason, any Lender is required to refund such payment
or pay such amount to Borrower or to any other person;

         (d) Any dissolution of Borrower or any sale, lease or transfer of all
or any part of Borrower's assets;

         (e) Any failure of Lender to notify Guarantor of the acceptance of this
Agreement or of the making of loans or other extensions of credit in reliance on
this Agreement or of the failure of Borrower to make any payment due by Borrower
to Lender;

         (f) Any "one action" or "anti-deficiency" law or any other law which
may prevent Lender from bringing any action, including a claim for deficiency,
against Guarantor, before or after Lender's commencement or completion of any
foreclosure action, or any action in lieu of foreclosure; and/or

         (g) Any election of remedies by Lender that may destroy or impair
Guarantor's subrogation rights or Guarantor's right to proceed for reimbursement
against Borrower or any other guarantor, surety or endorser of any of Borrower's
Secured Liabilities, including without limitation any loss of rights Guarantor
may suffer by reason of any law limiting, qualifying or discharging Borrower's
Secured Liabilities.

         This Agreement and Guarantor's obligations and liabilities hereunder
shall continue to be effective, and/or shall automatically and retroactively be
reinstated if a release or discharge has occurred, as the case may be, if at any
time any payment or part thereof to Lender with respect to any of Borrower's
Secured Liabilities is rescinded or must otherwise be restored by Lender
pursuant to any insolvency, bankruptcy, reorganization, receivership, or any
other debt relief granted to Borrower or to any other party. In the event that
Lender must rescind or restore any payment received by Lender in satisfaction of
Borrower's Secured Liabilities, any prior release or discharge from the terms of
this Agreement given to any Guarantor shall be without effect, and this
Agreement and Guarantor's obligations and liabilities hereunder shall
automatically be renewed or reinstated and shall remain in full force and effect
to the same degree and extent as if such a release or discharge was never
granted.

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It is the intention of Lender and Guarantor that Guarantor's obligations and
liabilities hereunder shall not be discharged except by Guarantor's full and
complete performance of such obligations and liabilities and then only to the
extent of such performance.

         SECTION 8. Representations and Warranties. Each Guarantor hereby
represents and warrants that:

         (a) The representations and warranties made in writing by the Borrower
with respect to such Guarantor in the Loan Agreement are true and correct.

         (b) Such Guarantor is duly organized, validly existing and in good
standing under the laws of the state of its incorporation or formation, has the
power to own its property and to carry on its business as now being conducted
and is duly qualified to do business and is in good standing in each
jurisdiction in which the character of the properties owned by it therein or in
which the transaction of its business makes such qualification necessary and the
failure to so qualify would have a material adverse effect on its financial
condition, business or operations.

         (c) Such Guarantor has full power and authority to execute and deliver
this Agreement and to incur the obligations provided for herein, all of which
have been duly authorized by all proper and necessary corporate action.

         (d) Borrower owns one hundred (100%) percent of the voting and
ownership equity interests of such Guarantor, and a portion of the proceeds of
the Note may be advanced to Guarantor and thus the Secured Liabilities are being
incurred for and will inure to the benefit of such Guarantor, which benefit is
hereby acknowledged.

         (e) Such Guarantor has examined or has an opportunity to examine each
of the Loan Agreement and Loan Documents pertaining thereto executed and
delivered prior to or on the date hereof.

         (f) This Agreement constitutes the valid and binding obligations of
such Guarantor, enforceable in accordance with its terms (except that
enforcement may be subject to any applicable bankruptcy, insolvency or similar
laws generally affecting the enforcement of creditors' rights).

         (g) The execution, delivery and performance by such Guarantor of this
Agreement will not violate any contract, agreement, law, regulation, order or
judgment to which Guarantor is subject.

         (h) The execution, delivery and performance by such Guarantor of this
Agreement did not and do not require the consent or approval of any other
person, corporation, partnership, limited liability company or other legal
entity or governmental agency or entity.

         (i) All financial statements of such Guarantor (if any) delivered to
Lender fairly and accurately present the financial condition of Guarantor and
have been prepared in accordance with generally accepted accounting principles
consistently applied throughout the period involved. Since the close of the
period covered by the latest financial statement delivered to Lender with
respect to Guarantor, there has been no material adverse change in the assets,
liabilities or financial condition of Guarantor.

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         SECTION 9. Covenants.

         (a) Each Guarantor will at all times comply with the affirmative and
negative covenants undertaken by the Borrower with respect to such Guarantor in
the Loan Agreement.

         (b) Each Guarantor will promptly notify Lender in writing upon becoming
aware of any change or effect that individually or in the aggregate does or
could reasonably be anticipated to materially adversely affect the business,
prospects, profits, property or condition (financial or otherwise) of Guarantor,
including without limitation the arising of any litigation, governmental
investigation or arbitration or dispute threatened against or affecting
Guarantor.

         (c) Each Guarantor will file all tax returns and reports required to be
filed and pay and discharge promptly when due all taxes, assessments and
governmental charges or levies imposed upon it or upon income or upon any of its
property (including production, severance, windfall profit, excise and other
taxes assessed against or measured by the production of, or the value or
proceeds of production of, oil and gas properties) as well as all claims of any
kind (including claims for labor, materials, supplies and rent) which, if
unpaid, might become a Lien upon any or all of Lender's collateral under the
Collateral Documents; provided, however, Guarantor shall not be required to pay
any such tax, assessment, charge, levy or claim if the amount, applicability or
validity thereof shall currently be contested in good faith by appropriate
proceedings diligently conducted and if the contesting party shall have set up
reserves therefor adequate under generally accepted accounting principles
(provided that such reserves may be set up under generally accepted accounting
principles) and so long as the payment of same is not a condition to be met in
order to maintain an oil, gas or mineral lease in force.

         (d) Each Guarantor agrees to maintain all of its primary collection,
disbursement and operating accounts with Lender.

         SECTION 10. Enforcement of Guarantor's Obligations and Liabilities.
Each Guarantor agrees that following the occurrence of an Event of Default,
should Lender deem it necessary to file an appropriate collection action to
enforce Guarantor's obligations and liabilities under this Agreement, Lender may
commence such a civil action against Guarantor without the necessity of first
(i) attempting to collect Borrower's Secured Liabilities from Borrower or from
any other guarantor, surety or endorser, whether through filing of suit or
otherwise, (ii) attempting to exercise against any collateral directly or
indirectly securing repayment of any of Borrower's Secured Liabilities, whether
through the filing of an appropriate foreclosure action or otherwise, or (iii)
including Borrower or any other guarantor, surety or endorser of any of
Borrower's Secured Liabilities as an additional party defendant in such a
collection action against Guarantor. If there is more than one guarantor under
this Agreement, the Guarantor additionally agrees that Lender may file an
appropriate collection and/or enforcement action against any one or more of
them, without impairing the rights of Lender against any other guarantor under
this Agreement. In the event that Lender should ever deem it necessary during
the continuance of a Default (as defined in and occurring under the Loan
Agreement) to refer this Agreement to attorneys-at-law for the purpose of
enforcing Guarantor's obligations and liabilities hereunder, or of protecting or
preserving Lender's rights hereunder, Guarantor agrees to reimburse the Lender
for its reasonable attorneys' fees and disbursements. Guarantor additionally
agree that Lender shall not be liable for failure to use diligence in the
collection of any of Borrower's Secured Liabilities or any collateral security
therefor, or in creating or preserving the liability of any person liable on any

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such Secured Liabilities, or in creating, perfecting or preserving any security
for any such Secured Liabilities.

         SECTION 11. Additional Documents. Upon the reasonable request of
Lender, each Guarantor will, at any time, and from time to time, duly execute
and deliver to Lender any and all such further instruments and documents, and
supply such additional information, as may be necessary or advisable in the
opinion of Lender, to further evidence or perfect this Agreement.

         SECTION 12. Transfer of Secured Liabilities. This Agreement is for the
benefit of Lender and for such other person or persons as may from time to time
become or be the holders of any of Borrower's Secured Liabilities hereby
guaranteed and this Agreement shall be transferable and negotiable, with the
same force and effect and to the same extent as Borrower's Secured Liabilities
may be transferable, it being understood that, upon the transfer or assignment
by Lender of any of Borrower's Secured Liabilities hereby guaranteed, the legal
holder of such Secured Liabilities shall have all of the rights granted to
Lender under this Agreement.

         Each Guarantor hereby recognizes and agrees that Lender may, from time
to time, one or more times, transfer any portion of Borrower's Secured
Liabilities to one or more third parties in accordance with the terms of the
Loan Agreement. Such transfers may include, but are not limited to, sales of a
participation interest in such Secured Liabilities in favor of one or more third
party lenders in accordance with any applicable terms in the Loan Agreement.
Guarantor specifically agrees and consents to all such transfers and assignments
and Guarantor further waives any subsequent notice of and right to consent to
any such transfers and assignments as may be provided under applicable Louisiana
(or other) law. Guarantor additionally agrees that the purchaser of a
participation interest in Borrower's Secured Liabilities will be considered as
the absolute owner of a percentage interest of such Secured Liabilities and that
such a purchaser will have all of the rights granted to the purchaser under any
participation agreement governing the sale of such a participation interest,
provided that such participation agreement cannot increase or alter the
obligations of Guarantor (other than as to the number or identity of Guarantor's
obligees).

         SECTION 13. Deposit Accounts. As collateral security for the repayment
of each Guarantor's obligations and liabilities under this Agreement, and for
the Borrower's Secured Liabilities, each Guarantor hereby grants Lender, as well
as its successors and assigns, a continuing security interest in, and the right
to apply at any time and from time to time during the continuance of an Event of
Default under the Loan Agreement, any and all funds, investment property and
proceeds that Guarantor may then have on deposit with or in the possession or
control of Lender and its successors or assigns or in certificates of deposit or
deposit accounts as to which Guarantor is account holder (with the exception of
funds deposited in IRA, pension or other tax-deferred deposit accounts), towards
repayment of any of Borrower's Secured Liabilities subject to this Agreement.
Guarantor agrees that any holder of a participation in the Note may exercise any
and all rights of counter-claim, set-off, banker's lien and other liens with
respect to any and all monies owing by Guarantor to such holder as fully as if
such holder of a participation were a holder of a note in the amount of such
participation. Guarantor waives and subordinates in favor of Lender any right of
set off (however arising, contractual or statutory) which it has or may
subsequently have with respect to any accounts payable owing by Guarantor to
Borrower or any of the Borrower's revenues, funds or monies comprising Lender's
collateral under the Collateral Documents which now or hereafter may be in the
possession or control of Guarantor including without limitation any funds in any
deposit account.

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         SECTION 14. Marshaling. The Guarantor shall not at any time hereafter
assert any right under any law pertaining to marshaling (whether of assets or
liens) and the Guarantor expressly agree that the Lender may execute or
foreclose upon the Collateral Documents in such order and manner as the Lender,
in its sole discretion, deems appropriate.

         SECTION 15. Amendment. No amendment, modification, consent or waiver of
any provision of this Agreement, and no consent to any departure by Guarantor
therefrom, shall be effective unless the same shall be in writing signed by a
duly authorized officer of Lender, and then shall be effective only to the
specific instance and for the specific purpose for which given.

         SECTION 16. Successors and Assigns Bound. Each Guarantor's obligations
and liabilities under this Agreement shall be binding upon Guarantor's
successors, heirs, legatees, devisees, administrators, executors and assigns.
The rights and remedies granted to Lender under this Agreement shall also inure
to the benefit of Lender's successors and assigns, as well as to any and all
subsequent holder or holders of any of Borrower's Secured Liabilities subject to
this Agreement.

         SECTION 17. Caption Headings. Caption headings of the sections of this
Agreement are for convenience purposes only and are not to be used to interpret
or to define their provisions. In this Agreement, whenever the context so
requires, the singular includes the plural and the plural also includes the
singular.

         SECTION 18. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED AND
CONSTRUED IN ACCORDANCE WITH THE SUBSTANTIVE LAWS OF THE STATE OF TEXAS.

         SECTION 19. Severability. If any provision of this Agreement is held to
be illegal, invalid or unenforceable under present or future laws effective
during the term hereof, such provision shall be fully severable, this Agreement
shall be construed and enforceable as if the illegal, invalid or unenforceable
provision had never comprised a part of it, and the remaining provisions of this
Agreement shall remain in full force and effect and shall not be affected by the
illegal, invalid or unenforceable provision or by its severance herefrom.

         SECTION 20. Waiver of Jury Trial; Consent to Jurisdiction.

         (a) Each Guarantor hereby waives trial by jury in any action or
proceeding to which Guarantor and Lender may be parties arising out of or in any
way pertaining to this Agreement. It is agreed and understood that this waiver
constitutes a waiver of trial by jury of all claims against all parties to such
actions or proceedings, including claims against parties who are not parties to
this Agreement. This waiver is knowingly, willingly and voluntarily made by
Guarantor, and Guarantor hereby represents that no representations of fact or
opinion have been made by any individual to induce this waiver of trial by jury
or to in any way modify or nullify its effect. Guarantor further represents that
it has been represented in the signing of this Agreement and in the making of
this waiver by independent legal counsel, selected by its own free will, and
that it had the opportunity to discuss this waiver with counsel.

         (b) Each Guarantor hereby irrevocably consents to the non-exclusive
jurisdiction of the state courts of Louisiana, and of the Federal Eastern
District Court in Louisiana, and agrees that any action or proceeding arising
out of or brought to enforce the provisions of this Agreement may be

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<PAGE>

brought in any court having subject matter jurisdiction. Each Guarantor hereby
irrevocably waives any objections that it may now or hereafter have to the venue
of any such action or proceeding in any such court and that any such action or
proceeding was brought in an inconvenient court and agrees not to plead or claim
the same. Each Guarantor agrees that nothing herein such limit the Lender's
right to sue in any other jurisdiction.

         SECTION 21. Notices. Any notice or demand which by provision of this
Agreement is required or permitted to be given by one party to the other party
hereunder shall be given by (i) deposit, postage prepaid, in the mail,
registered or certified mail, or (ii) delivery to a recognized express courier
service, or (iii) delivery by hand, or (iv) by facsimile, in each case addressed
(until another address or addresses is given in writing by such party to the
other party) as follows:


               If to any Guarantor:      9400 North Broadway, Suite 600
                                         Oklahoma City, Oklahoma 73114
                                         Attention: President
                                         Facsimile Number: (405) 600-0600

               If to Lender:             Hibernia National Bank
                                         P. O. Box 61540 New Orleans,
                                         Louisiana 70161

                                                       or

                                         313 Carondelet Street
                                         New Orleans, Louisiana 70130

                                         Attention: Manager
                                                    Energy/Maritime Department
                                         Facsimile Number: (504) 533-5434


All notices sent by facsimile transmission shall be deemed received by the
addressee upon the transmitter's receipt of acknowledgment of receipt from the
offices of such addressee (if before 5:00 p.m. on a business day; if later, then
on the next business day).

         SECTION 22. Compliance with Usury Laws. It is expressly stipulated and
agreed to be the intent of Guarantor and Lender at all times to comply with the
applicable Texas law governing the maximum non-usurious rate or amount of
interest payable on or in connection with the Borrower's Secured Liabilities (or
applicable United States federal law to the extent that it permits Lender to
contract for, charge, take, reserve or receive a greater amount of interest than
under Texas law). If the applicable law is ever judicially interpreted so as to
render usurious any amount called for under the Note or any other Loan Document,
or contracted for, charged, taken, reserved or received with respect to the loan
evidenced by the Note and/or the Loan Documents, or if the acceleration of the
maturity of the Borrower's Secured Liabilities or if any prepayment by Guarantor
results in Guarantor having paid any interest in excess of the maximum
non-usurious rate permitted by law, then it is Guarantor's and Lender's express
intent that all excess amounts theretofore collected by Lender be credited on
the principal balance of the Borrower's Secured Liabilities (or, if the
Borrower's Secured Liabilities has

                                       11
<PAGE>

been or would thereby be paid in full, refunded to Guarantor), and the
provisions of the Note and the other Loan Documents immediately be deemed
reformed and the amounts thereafter collectible thereunder reduced, without the
necessity of the execution of any new document, so as to comply with the
applicable law, but so as to permit the recovery of the fullest amount otherwise
called for hereunder and thereunder. The right to accelerate maturity of the
Borrower's Secured Liabilities does not include the right to accelerate any
interest which has not otherwise accrued on the date of such acceleration. All
sums paid or agreed to be paid to Lender for the use, forbearance or detention
of the Borrower's Secured Liabilities shall, to the extent permitted by
applicable law, be amortized, prorated, allocated and spread throughout the full
term of the Borrower's Secured Liabilities until payment in full so that the
rate or amount of interest on account of the Borrower's Secured Liabilities does
not exceed the applicable usury ceiling. As used in this Section 22, the term
"Loan Documents" shall mean all of the Loan Documents as such term is defined in
Section 1(b) hereof, together with this Agreement as may from time to time be
amended, supplemented, renewed or restated.

         IN WITNESS WHEREOF, each Guarantor has executed this Agreement in favor
of the Lender on the day, month and year first written above.


                                        ENDEAVOR PIPELINE INC.


                                        By: /s/ Ken L. Kenworthy, Sr.
                                            --------------------------------
                                            Name:   Ken L. Kenworthy, Sr.
                                            Titles: President

ACCEPTED:
---------

HIBERNIA NATIONAL BANK


By: /s/ H. Charles Voorhies IV
    -------------------------------
    Name:  H. Charles Voorhies IV
    Title: Vice President


July 29, 2005

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<PAGE>


STATE OF OKLAHOMA         )
                          )
                          ) SS:
                          )
COUNTY OF OKLAHOMA        )



         BEFORE ME, the undersigned Notary Public duly commissioned qualified
and sworn within and for the State and County written above, personally came and
appeared Ken L. Kenworthy, Sr., to me personally known, and who being by me duly
sworn, did say that he is the authorized President of Endeavor Pipeline Inc.,
whose name is subscribed to the foregoing Guaranty Agreement and that he
executed the foregoing Guaranty Agreement by authority of said corporation's
Board of Directors on behalf of said corporation.

         THUS DONE AND SIGNED before me and the two undersigned witnesses in the
County and State aforesaid, on this 29th day of July, 2005. Witness my hand and
official seal.


WITNESSES:


/s/ Amber Croisant                            /s/ Ken L. Kenworthy, Sr.
-------------------------                     -----------------------------
Name:                                         Name: Ken L. Kenworthy, Sr.

/s/ Marilyn Leonard
-------------------------
Name:


                                              /s/ Debra Barker
                                              -----------------------------
                                              NOTARY PUBLIC


                                              Seal

                                              My Commission expires: 3-16-06
                                              Comm # 02004134



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