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                                                                  EXHIBIT 10.29

                            INTEREST PLEDGE AGREEMENT


         THIS INTEREST PLEDGE AGREEMENT (the "Agreement"), dated February 26,
2004, is made and entered into by and among Knox Gas, LLC, a Delaware limited
liability company ("Pledgor"), and Continental Southern Resources, Inc., a
Nevada corporation (the "Secured Party").

         WHEREAS, pursuant to that certain Interest Purchase Agreement, dated as
of even date herewith (the "Purchase Agreement"), by and between the Pledgor and
the Secured Party, the Pledgor purchased the Secured Party's ninety-nine percent
(99%) limited partnership interest (the "LP Interest") in Knox Miss. Partners,
L.P. ("Knox Miss") and the Secured Party's one percent (1%) membership interest
in Knox Miss., LLC ("Knox LLC"), the general partner in Knox Miss (the
"Membership Interest"; together with the LP Interest, the "Interests"), and
issued that certain Secured Promissory Note dated February 26, 2004 in the
principal amount of US $4,500,000 (the "Note"); and

         WHEREAS, in order to secure the Pledgor's obligations under the Note,
the Secured Party has requested that the Pledgor pledge and grant a security
interest in and to the Interests of the Pledgor set forth on Schedule A hereto.

         NOW, THEREFORE, intending to be legally bound hereby, the parties
hereto hereby agree as follows:

         1. Defined Terms.


         (a) Except as otherwise expressly provided herein, capitalized terms
used in this Agreement shall have the respective meanings assigned to them in
the Purchase Agreement or the Note, as applicable. Where applicable and except
as otherwise expressly provided herein, terms used herein (whether or not
capitalized) shall have the respective meanings assigned to them in the Uniform
Commercial Code, as amended from time to time (the "Code").

         (b) "Pledged Collateral" shall mean and include the following: (i) the
Interests listed on Schedule A attached hereto and made a part hereof, and all
rights and privileges pertaining thereto, including, without limitation, all
present and future securities and other ownership interests receivable in
respect of, or in exchange for, such Interests, all rights under operating
agreements, member agreements, security holder agreements and other similar
agreements relating to such Interests, all rights to subscribe for securities
and other ownership interests incident to or arising from ownership of such
Interests, all cash, interest, securities and other dividends or distributions
paid or payable on such Interests, and all books and records (whether paper,
electronic or any other medium) pertaining to the foregoing, including, without
limitation, all partnership record and transfer books, and (ii) whatever is
received when any of the foregoing is sold, exchanged, replaced or otherwise
disposed of, including all proceeds thereof, as such term is defined in the
Code.

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         2. Grant of Security Interest.

         To secure the payment and performance of all obligations and of all
indebtedness of Pledgor under the Note (collectively, the "Secured
Obligations"), Pledgor hereby grants to the Secured Party a first priority
security interest in and hereby pledges to the Secured Party, all of such
Pledgor's now existing and hereafter acquired or arising right, title and
interest in, to and under the Pledged Collateral whether now or hereafter
existing and wherever located.

         3. Further Assurances.

         Prior to or concurrently with the execution of this Agreement, and
thereafter at any time and from time to time upon reasonable request of the
Secured Party, Pledgor shall execute and deliver to the Secured Party all
financing statements, continuation financing statements, assignments,
certificates and documents of title, affidavits, reports, notices, schedules of
account, letters of authority, further pledges, powers of attorney and all other
documents (collectively, the "Security Documents") which the Secured Party may
reasonably request, in form reasonably satisfactory to the Secured Party, and
take such other action which the Secured Party may reasonably request, to
perfect and continue perfected and to create and maintain the first priority
status of the Secured Party's security interest in the Pledged Collateral and to
fully consummate the transactions contemplated under this Agreement. Pledgor
hereby irrevocably makes, constitutes and appoints the Secured Party as
Pledgor's true and lawful attorney with power to sign the name of such Pledgor
on all or any of the documents which the Secured Party determines must be
executed, filed, recorded or sent in order to perfect or continue perfected the
Secured Party' security interest in the Pledged Collateral in any jurisdiction.
Such power, being coupled with an interest, is irrevocable until all of the
Secured Obligations have been indefeasibly full in paid and the Note have
terminated.

         4. Representations and Warranties.

         Pledgor hereby represents and warrants to the Secured Party as follows:

         (a) Pledgor has and will continue to have (or, in the case of
after-acquired Pledged Collateral, at the time such Pledgor acquires rights in
such Pledged Collateral, will have and will continue to have), title to the
Pledged Collateral, free and clear of all liens.

         (b) The securities constituting the Pledged Collateral have been duly
authorized and validly issued to Pledgor (as set forth on Schedule A hereto),
and are fully paid and nonassessable.

         (c) The security interests in the Pledged Collateral granted hereunder
are valid, perfected and of first priority, subject to the lien of no other
Person.

         (d) Except as provided in the Limited Partnership Agreement of Knox
Miss (the "Limited Partnership Agreement") and the Operating Agreement of Knox
LLC, there are no restrictions upon the transfer of the Pledged Collateral and
Pledgor has the power and authority and


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right to transfer the Pledged Collateral owned by Pledgor free of any
encumbrances and without obtaining the consent of any other Person.

         (e) Pledgor has all necessary power to execute, deliver and perform
this Agreement.

         (f) There are no actions, suits, or proceedings pending or, to
Pledgor's best knowledge after due inquiry, threatened against or affecting
Pledgor with respect to the Pledged Collateral, at law or in equity or before or
by any governmental authority, and Pledgor is not in default with respect to any
judgment, writ, injunction, decree, rule or regulation which could adversely
affect Pledgor's performance hereunder.

         (g) This Agreement has been duly executed and delivered and constitutes
the valid and legally binding obligation of Pledgor, enforceable in accordance
with its terms, except to the extent that enforceability of this Agreement may
be limited by applicable bankruptcy, insolvency, reorganization, moratorium or
other similar laws affecting the enforceability of creditors' rights generally
or limiting the right of specific performance.

         (h) Neither the execution and delivery by Pledgor of this Agreement,
nor the compliance with the terms and provisions hereof, will violate any
provision of any law or conflict with or result in a breach of any of the terms,
conditions or provisions of any judgment, order, injunction, decree or ruling of
any governmental authority to which Pledgor is subject or any provision of any
agreement, understanding or arrangement to which Pledgor is a party or by which
Pledgor is bound.

         (i) The address of Pledgor's chief executive office is as set forth on
the signature page hereto.

         (j) All rights of Pledgor in connection with its ownership of the
Interests are evidenced and governed solely by the agreements, certificate of
partnership, Limited Partnership Agreement and other organizational documents of
Knox Miss and the agreements, certificate of organization, Operating Agreement
and other organizational documents of Knox LLC, and no shareholder or other
similar agreements are applicable to the Pledged Collateral.

         5. General Covenants.

         Pledgor hereby covenants and agrees as follows:

         (a) Pledgor shall do all reasonable acts that may be necessary and
appropriate to maintain, preserve and protect the Pledged Collateral. Pledgor
shall be responsible for the risk of loss of, damage to, or destruction of the
Pledged Collateral owned by Pledgor, unless such loss is the result of the gross
negligence or willful misconduct of any Secured Party. Pledgor shall notify the
Secured Party in writing ten (10) days prior to any change in such Pledgor's
chief executive office address.


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         (b) Pledgor shall appear in and defend any action or proceeding of
which Pledgor is aware which could reasonably be expected to affect Pledgor's
title to, or the Secured Party's interest in, the Pledged Collateral or the
proceeds thereof; provided, however, that with the consent of the Secured Party,
Pledgor may settle such actions or proceedings with respect to the Pledged
Collateral, which consent shall not be unreasonably withheld or delayed.

         (c) Pledgor shall, and shall cause Knox Miss and Knox LLC to, keep
separate, accurate and complete records of the Pledged Collateral, disclosing
the Secured Party's security interest hereunder.

         (d) Pledgor shall comply with all laws applicable to the Pledged
Collateral unless any noncompliance would not individually or in the aggregate
materially impair the use or value of the Pledged Collateral or the Secured
Party's rights hereunder.

         (e) Pledgor shall pay any and all taxes, duties, fees or imposts of any
nature imposed by any governmental authority on any of the Pledged Collateral,
except to the extent contested in good faith by appropriate proceedings.

         (f) To the extent, following the date hereof, Pledgor acquires
securities, shares, capital stock or other ownership interests described in the
definition of Pledged Collateral, in respect of, in exchange for, or upon the
conversion of, the Pledged Collateral, such securities, shares, capital stock or
ownership interests shall be subject to the terms hereof and, upon such
acquisition, shall be deemed to be hereby pledged to the Secured Party, and
Pledgor thereupon shall deliver all such securities, shares, capital stock, and
other ownership interests together with an updated Schedule A hereto, to the
Secured Party.

         (g) Except as set forth in Section 15 hereof, during the term of this
Agreement, Pledgor shall not sell, assign, replace, retire, transfer or
otherwise dispose of its Pledged Collateral.

         6. Other Rights With Respect to Pledged Collateral.

         (a) In addition to the other rights with respect to the Pledged
Collateral granted to the Secured Party hereunder, at any time and from time to
time, after and during the continuation of any default under the Note, the
Secured Party, at its option and at the expense of the Pledgor, may (a) transfer
into the name of the Secured Party or into the name of its nominee, all or any
part of the Pledged Collateral, thereafter receiving all dividends, income or
other distributions upon the Pledged Collateral; (b) take control of and manage
all or any of the Pledged Collateral; (c) apply to the payment of any of the
Secured Obligations, whether any be due and payable or not, any moneys,
including cash dividends, distributions and income from any Pledged Collateral,
now or hereafter in the hands of the Secured Party, on deposit or otherwise,
belonging to Pledgor, as the Secured Party in its sole discretion shall
determine; and (d) do anything that Pledgor is required but fails to do
hereunder.

         (b) In the event that upon the occurrence of any default under the Note
and while such default shall be continuing the Secured Party desires to exercise
any of its rights or remedies


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under this Agreement, it shall deliver written notice (a "Default Notice") to
the Pledgor, which notice shall be dated and state that a default under the Note
has occurred and is continuing, that it desires to exercise certain of its
rights and remedies hereunder and direct the Pledgor to deliver the Pledged
Collateral to the Secured Party. Unless the Secured Party is notified in writing
by the Pledgor within five (5) days from the date of the Default Notice that the
Pledgor disputes the Secured Party's right to exercise any of its rights or
remedies hereunder, the Pledgor shall promptly deliver the Pledged Collateral to
the Secured Party. If the Secured Party is notified in writing by the Pledgor
within five (5) days from the date of the Default Notice that the Pledgor in
good faith contests the right of the Secured Party to exercise its rights or
remedies hereunder, then, and in that event, the parties shall be permitted to
submit the issues in dispute to arbitration in accordance with the provisions of
Section 17 of this Agreement.

         7. Additional Remedies Upon Event of Default.

         Upon the occurrence of any default under the Note and while such
default shall be continuing, the Secured Party shall have, in addition to all
rights and remedies of a secured party under the Code or other applicable law,
and in addition to its rights under Section 6 above, the Purchase Agreement and
the Note, the following rights and remedies:

         (a) The Secured Party may, after ten (10) days' advance notice to the
Pledgor, sell, assign, give an option or options to purchase or otherwise
dispose of the Pledged Collateral or any part thereof at public or private sale,
at the Secured Party's offices or elsewhere, for cash, on credit or for future
delivery, and upon such other terms as the Secured Party may deem commercially
reasonable. Pledgor agrees that ten (10) days' advance notice of the time and
place of any public sale or the time after which any private sale is to be made
shall constitute reasonable notification. The Secured Party shall not be
obligated to make any sale of Pledged Collateral regardless of notice of sale
having been given. The Secured Party may adjourn any public or private sale from
time to time by announcement at the time and place fixed therefor, and such sale
may, without further notice, be made at the time and place to which it was so
adjourned. Pledgor recognizes that the Secured Party may be compelled to resort
to one or more private sales of the Pledged Collateral to a restricted group of
purchasers who will be obliged to agree, among other things, to acquire such
securities for their own account for investment and not with a view to the
distribution or resale thereof.

         (b) The proceeds of any collection, sale or other disposition of the
Pledged Collateral, or any part thereof, shall, after the Secured Party has made
all deductions of expenses, including but not limited to, attorneys' fees and
other expenses incurred in connection with repossession, collection, sale or
disposition of such Pledged Collateral or in connection with the enforcement of
the Secured Party's rights with respect to the Pledged Collateral, including in
any insolvency, bankruptcy or reorganization proceedings, be applied against the
Secured Obligations, whether or not all the same be then due and payable, as
follows:

               (i) first, to the Secured Obligations and to reimburse the
Secured Party for out-of-pocket costs, expenses and disbursements, including
without limitation reasonable attorneys' fees and legal expenses, incurred by
the Secured Party in connection with realizing on the


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Pledged Collateral including expenses incurred by the Secured Party for the
reasonable maintenance, preservation, protection or enforcement of, or
realization upon, the Pledged Collateral, including without limitation advances
for taxes, insurance, and the like, and reasonable expenses incurred to sell or
otherwise realize on, or prepare for sale of or other realization on, any of the
Pledged Collateral, in such order as the Secured Party may determine in its
discretion; and

               (ii) the balance, if any, as required by law.

         8. Secured Party's Duties.

         The powers conferred on the Secured Party hereunder are solely to
protect its interest in the Pledged Collateral and shall not impose any duty
upon it to exercise any such powers. Except for the safe custody of any Pledged
Collateral in its possession and the accounting for moneys actually received by
it hereunder, the Secured Party shall have no duty as to any Pledged Collateral
or as to the taking of any necessary steps to preserve rights against prior
parties or any other rights pertaining to any Pledged Collateral.

         9. No Waiver; Cumulative Remedies.

         No failure to exercise, and no delay in exercising, on the part of any
Secured Party, any right, power or privilege hereunder shall operate as a waiver
thereof, nor shall any single or partial exercise of any right, power or
privilege hereunder preclude any further exercise thereof or the exercise of any
other right, power or privilege. The remedies herein provided are cumulative and
not exclusive of any remedies provided under the Note and the Purchase Agreement
or by law. Pledgor waives any right to require the Secured Party to proceed
against any other person or to exhaust any of the Pledged Collateral or other
security for the Secured Obligations or to pursue any remedy in the Secured
Party's power.

         10. Assignment.

         All rights and obligations of the parties under this Agreement shall
inure to the benefit of their respective successors and assigns.

         11. Severability.

         Any provision of this Agreement that shall be held invalid or
unenforceable shall be ineffective without invalidating the remaining provisions
hereof.

         12. Governing Law.

         This Agreement shall be construed in accordance with and governed by
the internal laws of the State of Texas without regard to its conflicts of law
principles, except to the extent the validity or perfection of the security
interests or the remedies hereunder in respect of any Pledged Collateral are
governed by the law of a jurisdiction other than the State of Texas.


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         13. Notices.

         All notices, requests, demands, directions and other communications
(collectively, "notices") given to or made upon any party hereto under the
provisions of this Agreement shall be in writing (including telex or facsimile
communication) and shall be hand delivered, sent by a recognized overnight
courier or sent by telex or facsimile to the respective parties at the addresses
and numbers set forth in the signature page hereto or in accordance with any
subsequent unrevoked written direction from any party to the others. All notices
shall, except as otherwise expressly provided herein, be effective in the case
of telex or facsimile, when received, or in the case of hand delivered notice,
when hand delivered or, in the case of overnight couriered notice, the business
day after deposit with such courier.

         14. Specific Performance.

         The parties acknowledge and agree that, in addition to the other rights
of the parties hereunder and under the Note, because a party's remedies at law
for failure of any other party to comply with the provisions hereof would be
inadequate and that any such failure would not be adequately compensable in
damages, the parties agree that each the provisions hereof may be specifically
enforced.

         15. Voting Rights in Respect of the Pledged Collateral.

         So long as no default shall occur and be continuing under the Note,
Pledgor may exercise any and all voting rights pertaining to the Pledged
Collateral.

         16. Release of Pledged Collateral.


         An agreement evidencing the Pledged Collateral shall be released and
delivered to Pledgor after full payment of all principal and interest due under
the Note is made to the Secured Party. In the event such full payment of all
principal and interest is not so received by the Secured Party, the Secured
Party shall be permitted to submit the issues in dispute to arbitration in
accordance with the provisions of Section 17 of this Agreement.

         17. Arbitration.


         If a dispute arises as to the interpretation of this Agreement, it
shall be decided in an arbitration proceeding conforming to the Rules of the
American Arbitration Association applicable to commercial arbitration then in
effect at the time of the dispute. The arbitration shall take place in the
Commonwealth of Pennsylvania. The decision of the Arbitrators shall be
conclusively binding upon the parties and final, and such decision shall be
enforceable as a judgment in any court of competent jurisdiction. The parties
shall share equally the costs of the arbitration.


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         18. Entire Agreement; Amendments.


         This Agreement constitutes the entire agreement between the parties
with respect to the subject matter hereof and supersedes all prior agreements
relating to a grant of a security interest in the Pledged Collateral by Pledgor.
This Agreement may not be amended or supplemented except by a writing signed by
the Secured Party and the Pledgor.

         19. Counterparts.

         This Agreement may be executed in any number of counterparts and
delivered via facsimile, and by different parties hereto in separate
counterparts, each of which when so executed shall be deemed an original and all
of which taken together shall constitute but one and the same agreement.

         20. Descriptive Headings.

         The descriptive headings which are used in this Agreement are for the
convenience of the parties only and shall not affect the meaning of any
provision of this Agreement.



                  [Remainder of page intentionally left blank]


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                   SIGNATURE PAGE TO INTEREST PLEDGE AGREEMENT


         IN WITNESS WHEREOF, and intending to be legally bound, the parties
hereto have caused this Agreement to be duly executed as of the date first above
written.

                                  KNOX GAS, LLC


                                  By:  /s/ ERNEST BARTLETT
                                       ----------------------------------------
                                  Name:  Ernest Bartlett
                                  Title: President, FEQ Investments,
                                         Managing Member

                                         Address: 111 Presidential Blvd.
                                                  Suite 158A
                                                  Bala Cynwyd, PA 19004


                                  CONTINENTAL SOUTHERN RESOURCES, INC.

                                  By:  /s/ WILLIAM L. TRANSIER
                                       ----------------------------------------
                                       William L. Transier
                                       Co-Chief Executive Officer


                                         Address: 111 Presidential Blvd.
                                                  Suite 158A
                                                  Bala Cynwyd, PA 19004

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                                   SCHEDULE A
                                       TO
                            INTEREST PLEDGE AGREEMENT


                        DESCRIPTION OF PLEDGED COLLATERAL


Pledgor                                            Pledged Collateral
-------                                            ------------------

Knox                                     Gas, LLC The ninety-nine percent (99%)
                                         limited partnership interest in Knox
                                         Miss Partners, L.P., which limited
                                         partnership interest shall be released
                                         after payment in full of the principal
                                         due under the Note in accordance with
                                         Section 16 of this Interest Pledge
                                         Agreement.

                                         The one percent (1%) membership
                                         interest in Knox Miss, LLC, the general
                                         partner in Knox Miss. Partners, L.P.,
                                         which membership interest shall be
                                         released after payment in full of the
                                         principal due under the Note in
                                         accordance with Section 16 of this
                                         Interest Pledge Agreement.