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                                                                   Exhibit 10.15

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                           WAIVER AND FIFTH AMENDMENT
                               TO CREDIT AGREEMENT



                                     BETWEEN



                 HARKEN EXPLORATION COMPANY, XPLOR ENERGY, INC.
          HARKEN ENERGY WEST TEXAS, INC., SOUTH COAST EXPLORATION CO.,
                            XPLOR ENERGY SPV-1, INC.,
                         HARKEN GULF EXPLORATION COMPANY



                                       AND


                                  BANK ONE, NA,
                               AS AGENT AND LENDER
                        AND THE LENDERS SIGNATORY HERETO


                        Effective as of October 29, 2002



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             REDUCING REVOLVING LINE OF CREDIT OF UP TO $100,000,000

                       -----------------------------------



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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                          PAGE
                                                                          ----
<S>                                                                       <C>
ARTICLE I   DEFINITIONS .............................................       1
   1.01     Terms Defined Above .....................................       1
   1.02     Terms Defined in Agreement ..............................       1
   1.03     References ..............................................       1
   1.04     Articles and Sections ...................................       2
   1.05     Number and Gender .......................................       2
ARTICLE II  WAIVERS .................................................       2
   2.01     Waivers .................................................       2
   2.02     Limitation on Waivers ...................................       2
ARTICLE III AMENDMENTS ..............................................       2
   3.01     Amendment of Section 1.2 ................................       2
   3.02     Amendment of Section 2.9(a) .............................       2
ARTICLE IV  CONDITIONS ..............................................       3
   4.01     Receipt of Documents ....................................       3
   4.02     Accuracy of Representations and Warranties ..............       3
   4.03     Matters Satisfactory to Lenders .........................       3
ARTICLE V   REPRESENTATIONS AND WARRANTIES ..........................       4
ARTICLE VI  RATIFICATION ............................................       4
ARTICLE VII MISCELLANEOUS ...........................................       4
   7.01     Scope of Amendment ......................................       4
   7.02     Agreement as Amended ....................................       4
   7.03     Parties in Interest .....................................       4
   7.04     Rights of Third Parties .................................       4
   7.05     ENTIRE AGREEMENT ........................................       4
   7.06     GOVERNING LAW ...........................................       5
   7.07     JURISDICTION AND VENUE ..................................       5
</TABLE>

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                 WAIVER AND FIFTH AMENDMENT TO CREDIT AGREEMENT

     This WAIVER AND FIFTH AMENDMENT TO CREDIT AGREEMENT (this "Fifth
Amendment") is made and entered into effective as of October 29, 2002, between
HARKEN EXPLORATION COMPANY, a Delaware corporation, XPLOR ENERGY, INC., a Texas
corporation, HARKEN ENERGY WEST TEXAS, INC., a Delaware corporation, XPLOR
ENERGY SPV-1, INC., an Oklahoma corporation, and HARKEN GULF EXPLORATION
COMPANY, a Delaware corporation (collectively the "Borrower"), each lender that
is signatory hereto or becomes a signatory hereto as provided in Section 9.1,
(individually, together with its successors and assigns, a "Lender", and
collectively together with their respective successors and assigns, the
"Lenders"), and BANK ONE, NA, a national banking association, as agent for the
Lenders (in such capacity, together with its successors in such capacity
pursuant to the terms hereof, the "Agent") (as successor by merger to Bank One,
Texas, National Association).

                               W I T N E S S E T H

     WHEREAS, the above named parties did execute and exchange counterparts of
that certain Credit Agreement dated August 11, 2000, as amended by First
Amendment to Credit Agreement dated December 21, 2000, as further amended by
Second Amendment to Credit Agreement dated December 31, 2000, as further amended
by Third Amendment to Credit Agreement dated May 11, 2001, and as further
amended by Waiver and Fourth Amendment dated March 21, 2002 (the "Agreement"),
to which reference is here made for all purposes;

     WHEREAS, the parties subject to and bound by the Agreement are desirous of
amending the Agreement in the particulars hereinafter set forth;

     NOW, THEREFORE, in consideration of the mutual covenants and agreements of
the parties to the Agreement, as set forth therein, and the mutual covenants and
agreements of the parties hereto, as set forth in this Fifth Amendment, the
parties hereto agree as follows:

                                   ARTICLE I
                                  DEFINITIONS

     1.01 Terms Defined Above. As used herein, each of the terms "Agent,"
"Agreement," "Borrower," "Fifth Amendment," "Lender," and "Lenders" shall have
the meaning assigned to such term hereinabove.

     1.02 Terms Defined in Agreement. As used herein, each term defined in the
Agreement shall have the meaning assigned thereto in the Agreement, unless
expressly provided herein to the contrary.

     1.03 References. References in this Fifth Amendment to Article or Section
numbers shall be to Articles and Sections of this Fifth Amendment, unless
expressly stated herein to the contrary. References in this Fifth Amendment to
"hereby," "herein," hereinafter," hereinabove," "hereinbelow," "hereof," and
"hereunder" shall be to this Fifth Amendment in its entirety and not only to the
particular Article or Section in which such reference appears.

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     1.04 Articles and Sections. This Fifth Amendment, for convenience only, has
been divided into Articles and Sections and it is understood that the rights,
powers, privileges, duties, and other legal relations of the parties hereto
shall be determined from this Fifth Amendment as an entirety and without regard
to such division into Articles and Sections and without regard to headings
prefixed to such Articles and Sections.

     1.05 Number and Gender. Whenever the context requires, reference herein
made to the single number shall be understood to include the plural and likewise
the plural shall be understood to include the singular. Words denoting sex shall
be construed to include the masculine, feminine, and neuter, when such
construction is appropriate, and specific enumeration shall not exclude the
general, but shall be construed as cumulative. Definitions of terms defined in
the singular and plural shall be equally applicable to the plural or singular,
as the case may be.

                                   ARTICLE II
                                     WAIVERS

     2.01 Waivers. The Lenders hereby waive any Default or Event of Default
arising under the Agreement or any other Loan Document solely as a result of
violations of Sections 6.13 and 6.18 for the quarter ending September 30, 2002.

     2.02 Limitation on Waivers. The scope of the waivers set forth in Section
2.1 are expressly limited to their terms and do not extend to any other or
future breaches, Defaults, violations or Events of Default under the Agreement
or any other Loan Document.

                                  ARTICLE III
                                   AMENDMENTS

     The Borrower and the Lenders hereby amend the Agreement in the following
particulars:

     3.01 Amendment of Section 1.2. 1.01 Section 1.2 of the Agreement is hereby
amended as follows:

     The following definitions are amended to read as follows:

     "Current Assets" shall mean all assets which would, in accordance with
     GAAP, be included as current assets on the balance sheet of the Borrower or
     Guarantor, as the case may be, as of the date of calculation, plus any
     amounts available under this Agreement.

     "Current Liabilities" shall mean all liabilities which would, in accordance
     with GAAP, be included as current liabilities on the balance sheet of the
     Borrower or Guarantor, as the case may be, as of the date of calculation.

     3.02 Amendment of Section 2.9(a). Section 2.9(a) of the Agreement is hereby
amended as follows:

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     "2.9  Borrowing Base Determinations. (a) The Borrowing Base is acknowledged
     by the Borrower and the Lenders to be $5,287,000 effective upon execution
     of this Fifth Amendment. Commencing on November 1, 2002, and continuing on
     the first day of each calendar month until the next Borrowing Base review,
     the amount of the Borrowing Base shall be reduced by $225,000."

     3.03  Amendment of Section 6.13. Section 6.13 of the Agreement is hereby
amended to read as follows:

     "6.13 Current Ratio of the Guarantor. Guarantor shall not permit the ratio
     of Current Assets to Current Liabilities, but excluding current maturities
     under this Agreement and current maturities of the European Notes, to be
     less than 1.15 to 1.00 at any time."

     3.04  Amendment of Section 6.18. Section 6.18 of the Agreement is hereby
amended to read as follows:

     "6.18 Current Ratio of the Borrower. Borrower shall not permit, as of the
     close of any fiscal quarter, the ratio of Current Assets, but excluding
     inter-company receivables from the Guarantor, to Current Liabilities, but
     excluding current maturities under this Agreement, to be less than 1.00 to
     1.00 at any time."

                                   ARTICLE IV
                                   CONDITIONS

     The obligation of the Lenders to amend the Agreement as provided in Article
III is subject to the fulfillment of the following conditions precedent:

     4.01  Receipt of Documents. The Lenders shall have received, reviewed, and
approved the following documents and other items, appropriately executed when
necessary and in form and substance satisfactory to the Agent:

     (a)   multiple counterparts of this Fifth Amendment, as requested by the
           Agent;

     (b)   payment of $1,000,000 to reduce the outstanding Loan Balance to equal
           the amount of the Borrowing Base of $5,287,000; and

     (c)   such other agreements, documents, items, instruments, opinions,
           certificates, waivers, consents, and evidence as the Agent may
           reasonably request.

     4.02  Accuracy of Representations and Warranties. The representations and
warranties contained in Article IV of the Agreement and this Fifth Amendment
shall be true and correct.

     4.03  Matters Satisfactory to Lenders. All matters incident to the
consummation of the transactions contemplated hereby shall be satisfactory to
the Lenders.

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                                   ARTICLE V
                         REPRESENTATIONS AND WARRANTIES

     The Borrower hereby expressly re-makes, in favor of the Lenders, all of the
representations and warranties set forth in Article IV of the Agreement, and
represents and warrants that all such representations and warranties remain true
and unbreached.

                                   ARTICLE VI
                                  RATIFICATION

     Each of the parties hereto does hereby adopt, ratify, and confirm the
Agreement and the other Loan Documents, in all things in accordance with the
terms and provisions thereof, as amended by this Fifth Amendment.

                                  ARTICLE VII
                                  MISCELLANEOUS

     7.01 Scope of Amendment. The scope of this Fifth Amendment is expressly
limited to the matters addressed herein and this Fifth Amendment shall not
operate as a waiver of any past, present, or future breach, Default, or Event of
Default under the Agreement, except to the extent, if any, that any such breach,
Default, or Event of Default is remedied by the effect of this Fifth Amendment.

     7.02 Agreement as Amended. All references to the Agreement in any document
heretofore or hereafter executed in connection with the transactions
contemplated in the Agreement shall be deemed to refer to the Agreement as
amended by this Fifth Amendment.

     7.03 Parties in Interest. All provisions of this Fifth Amendment shall be
binding upon and shall inure to the benefit of the Borrower, the Agent and the
Lenders and their respective successors and assigns.

     7.04 Rights of Third Parties. All provisions herein are imposed solely and
exclusively for the benefit of the Agent, Lenders and the Borrower, and no other
Person shall have standing to require satisfaction of such provisions in
accordance with their terms and any or all of such provisions may be freely
waived in whole or in part by the Lenders at any time if in their sole
discretion it deems it advisable to do so.

     7.05 ENTIRE AGREEMENT. THIS FIFTH AMENDMENT CONSTITUTES THE ENTIRE
AGREEMENT BETWEEN THE PARTIES HERETO WITH RESPECT TO THE SUBJECT HEREOF AND
SUPERSEDES ANY PRIOR AGREEMENT, WHETHER WRITTEN OR ORAL, BETWEEN SUCH PARTIES
REGARDING THE SUBJECT HEREOF. FURTHERMORE IN THIS REGARD, THIS FIFTH AMENDMENT,
THE AGREEMENT, THE NOTE, THE SECURITY INSTRUMENTS, AND THE OTHER WRITTEN
DOCUMENTS REFERRED TO IN THE AGREEMENT OR EXECUTED IN CONNECTION WITH OR AS
SECURITY FOR THE NOTE REPRESENT, COLLECTIVELY, THE FINAL AGREEMENT AMONG THE
PARTIES THERETO AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR

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SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL
AGREEMENTS AMONG THE PARTIES.

     7.06 GOVERNING LAW. THIS FIFTH AMENDMENT, THE AGREEMENT AND THE NOTE SHALL
BE DEEMED TO BE CONTRACTS MADE UNDER AND SHALL BE CONSTRUED IN ACCORDANCE WITH
AND GOVERNED BY THE LAWS OF THE STATE OF TEXAS. THE PARTIES ACKNOWLEDGE AND
AGREE THAT THIS AGREEMENT AND THE NOTE AND THE TRANSACTIONS CONTEMPLATED HEREBY
BEAR A NORMAL, REASONABLE, AND SUBSTANTIAL RELATIONSHIP TO THE STATE OF TEXAS.

     7.07 JURISDICTION AND VENUE. ALL ACTIONS OR PROCEEDINGS WITH RESPECT TO,
ARISING DIRECTLY OR INDIRECTLY IN CONNECTION WITH, OUT OF, RELATED TO, OR FROM
THIS FIFTH AMENDMENT, THE AGREEMENT OR ANY OTHER LOAN DOCUMENT MAY BE LITIGATED
IN COURTS HAVING SITUS IN HARRIS COUNTY, TEXAS. EACH OF THE BORROWER AND THE
LENDERS HEREBY SUBMITS TO THE JURISDICTION OF ANY LOCAL, STATE, OR FEDERAL COURT
LOCATED IN HARRIS COUNTY, TEXAS, AND HEREBY WAIVES ANY RIGHTS IT MAY HAVE TO
TRANSFER OR CHANGE THE JURISDICTION OR VENUE OF ANY LITIGATION BROUGHT AGAINST
IT BY THE BORROWER OR THE LENDERS IN ACCORDANCE WITH THIS SECTION.

     IN WITNESS WHEREOF, this Fifth Amendment to Credit Agreement is executed
effective the date first hereinabove written.

                                   BORROWER

                                   HARKEN EXPLORATION COMPANY

                                   XPLOR ENERGY, INC.

                                   HARKEN ENERGY WEST TEXAS, INC.

                                   SOUTH COAST EXPLORATION CO.

                                   XPLOR ENERGY SPV-1, INC.

                                   HARKEN GULF EXPLORATION COMPANY

                                   By: /s/ Anna Williams
                                       ---------------------------------------
                                       Anna Williams
                                       Senior Vice President and Chief Financial
                                       Officer

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                             GUARANTOR

                             HARKEN ENERGY CORPORATION

                             By: /s/ Anna Williams
                                 ----------------------------------------------
                                     Anna Williams
                                     Senior Vice President and Chief Financial
                                     Officer

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                                            AGENT AND LENDER

                                            BANK ONE, NA (Main Office Chicago)

                                            By: /s/ Jo Linda Papadakis
                                               -------------------------------
                                                Jo Linda Papadakis
                                                Associate Director

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