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                                                                     EXHIBIT 4.9

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                         WESTPORT RESOURCES CORPORATION,
                              a Nevada corporation,
                                   as Issuer,


                             Each Subsidiary of the
                              Issuer listed on the
                             signatory pages hereto,
                            as Subsidiary Guarantors,


                                       and
                              THE BANK OF NEW YORK,
                                   as Trustee






                          SECOND SUPPLEMENTAL INDENTURE

                          Dated as of December 17, 2002

                                       to

                                    INDENTURE

                          Dated as of November 5, 2001


                    8 1/4% Senior Subordinated Notes due 2011

================================================================================




<PAGE>




                          SECOND SUPPLEMENTAL INDENTURE

         SECOND SUPPLEMENTAL INDENTURE (this "SUPPLEMENTAL INDENTURE"), dated as
of December 17, 2002, among Westport Resources Corporation, a Nevada corporation
(the "COMPANY"), the existing Subsidiary Guarantors under the indenture referred
to below (the "EXISTING SUBSIDIARY GUARANTORS"), the parties identified as New
Subsidiary Guarantors on the signature page hereto (the "NEW SUBSIDIARY
GUARANTORS") and The Bank of New York, as trustee under the indenture referred
to below (the "TRUSTEE").

                                   WITNESSETH:

         WHEREAS, the Company and the Existing Subsidiary Guarantors have
heretofore executed and delivered to the Trustee an indenture, dated as of
November 5, 2001 (the "ORIGINAL INDENTURE"), as amended by the First
Supplemental Indenture thereto, dated as of December 31, 2001 (together with the
Original Indenture, the "INDENTURE") providing for the issuance of 8 1/4% Senior
Subordinated Notes due 2011 (the "SECURITIES");

         WHEREAS, on November 5, 2001, the Company issued $275,000,000 in
principal amount of Securities; and

         WHEREAS, the Company has entered into that certain Purchase Agreement,
dated December 11, 2002, by and among the Company, the Subsidiary Guarantors,
Credit Suisse First Boston Corporation, J.P. Morgan Securities Inc., and Lehman
Brothers Inc., acting on behalf of themselves and as representatives of other
purchasers, pursuant to which, on this date, the Company is issuing $300,000,000
of Additional Securities as permitted by Sections 2.13 and 4.03(a) of the
Indenture (the "DECEMBER 2002 ADDITIONAL SECURITIES");

         WHEREAS, through the indirect acquisition of all of the membership
interests of Horse Creek Trading & Compression LLC and the formation of Westport
Field Services, LLC, the Company has acquired two new Subsidiaries;

         WHEREAS, Section 4.10 of the Indenture provides that, under certain
circumstances, the Company is required to cause its Subsidiaries to execute and
deliver to the Trustee a Guaranty Agreement pursuant to which such Subsidiaries
shall unconditionally guarantee all of the Company's obligations under the
Securities and the Indenture on the terms and conditions set forth herein; and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee, the
Company and the Existing Subsidiary Guarantors are authorized to execute and
deliver this Supplemental Indenture.

         NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Company, the Existing Subsidiary Guarantors, the New Subsidiary Guarantors and
the Trustee mutually covenant and agree for the equal and ratable benefit of the
holders of the Securities as follows:

         1. DEFINITIONS. (a) Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

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         (b) For all purposes of this Supplemental Indenture, except as
otherwise herein expressly provided or unless the context otherwise requires:
(i) the terms and expressions used herein shall have the same meanings as
corresponding terms and expressions used in the Indenture; and (ii) the words
"herein," "hereof" and "hereby" and other words of similar import used in this
Supplemental Indenture refer to this Supplemental Indenture as a whole and not
to any particular section hereof.

         2. AGREEMENT TO GUARANTEE. The New Subsidiary Guarantors hereby agree,
jointly and severally with all other Subsidiary Guarantors, to guarantee the
Company's obligations under the Securities and the Indenture on the same terms
and conditions as set forth in Articles 11 and 12 of the Indenture and to be
bound by all other applicable provisions of the Indenture. Except as expressly
amended hereby, the Indenture is in all respects ratified and confirmed and all
the terms, conditions and provisions thereof shall remain in full force and
effect. This Supplemental Indenture is a "GUARANTY AGREEMENT" as contemplated by
Section 4.10 of the Indenture and shall form a part of the Indenture for all
purposes, and every holder of Securities heretofore or hereafter authenticated
and delivered shall be bound hereby.

         3. EXISTING SUBSIDIARY GUARANTORS. Each Existing Subsidiary Guarantor
executes this Supplemental Indenture to: (i) ratify and confirm its existing
Subsidiary Guaranty as continuing to be in full force and effect; and (ii)
evidence its agreement to the terms of this Supplemental Indenture.

         4. DECEMBER 2002 ADDITIONAL SECURITIES. Attached hereto as Annex 1 is a
true and correct copy of the resolutions of the Board of Directors and the
Officers' Certificate required by Section 2.13 of the Indenture in connection
with the issuance of the December 2002 Additional Securities. The definition of
the term "ADDITIONAL SECURITIES" set forth in the Indenture is hereby
supplemented by adding the following sentence at the end of such definition: "On
December 17, 2002, the Company issued $300,000,000 of Additional Securities, as
more particularly described in the Second Supplemental Indenture hereto, dated
as of December 17, 2002."

         5. GOVERNING LAW. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT WITHOUT
GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT
THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

         6. TRUSTEE MAKES NO REPRESENTATION. The recitals herein contained are
made by the Company and the Subsidiary Guarantors and not by the Trustee, and
the Trustee assumes no responsibility for the correctness thereof. The Trustee
makes no representation as to the validity or sufficiency of this Supplemental
Indenture.

         7. COUNTERPARTS. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

         8. EFFECT OF HEADINGS. The Section headings herein are for convenience
only and shall not effect the construction thereof.

                                       2

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                            [SIGNATURE PAGE FOLLOWS]



                                       3

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

                                   WESTPORT RESOURCES CORPORATION

                                   By:  /s/ LON MCCAIN
                                        ----------------------------------------
                                        Lon McCain, Vice President, Treasurer
                                        and Chief Financial Officer


                                   EXISTING SUBSIDIARY GUARANTORS:

                                   WESTPORT CANADA LLC

                                   By:   WESTPORT OIL AND GAS COMPANY, L.P.

                                         By: WHG, INC.

                                              By:  /s/ LON MCCAIN
                                                  ------------------------------
                                                  Lon McCain, Vice President,
                                                  Treasurer and Chief Financial
                                                  Officer

                                   JERRY CHAMBERS EXPLORATION COMPANY

                                   By:   WESTPORT OIL AND GAS COMPANY, L.P.

                                         By: WHG, INC.

                                              By: /s/ LON MCCAIN
                                                  ------------------------------
                                                  Lon McCain, Vice President,
                                                  Treasurer and Chief Financial
                                                  Officer


                                   WESTPORT FINANCE CO.

                                   By:   /s/ LON MCCAIN
                                         ---------------------------------------
                                         Lon McCain, Treasurer


                                   WESTPORT ARGENTINA LLC

                                   By:   /s/ DONALD D. WOLF
                                         ---------------------------------------
                                         Donald D. Wolf, Manager


                                       S-1


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                                   WESTPORT OVERRIDING ROYALTY LLC

                                   By:   WESTPORT OIL AND GAS COMPANY, L.P.

                                         By: WHG, INC.

                                               By:  /s/ LON MCCAIN
                                                    ----------------------------
                                                    Lon McCain, Vice President,
                                                    Treasurer and Chief
                                                    Financial Officer


                                  WESTPORT OIL AND GAS COMPANY, L.P.

                                  By: WHG, INC.

                                       By:  /s/ LON MCCAIN
                                            ------------------------------------
                                            Lon McCain, Vice President,
                                            Treasurer and Chief Financial
                                            Officer


                                  WHG, INC.

                                  By:  /s/ LON MCCAIN
                                       -----------------------------------------
                                       Lon McCain, Vice President, Treasurer and
                                       Chief Financial Officer


                                  WHL, INC.

                                  By:  /s/ LON MCCAIN
                                       -----------------------------------------
                                       Lon McCain, Vice President, Treasurer and
                                       Chief Financial Officer


                                      S-2


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                                  NEW SUBSIDIARY GUARANTORS:

                                  HORSE CREEK TRADING & COMPRESSION LLC

                                  By:   WESTPORT OIL AND GAS COMPANY, L.P.

                                        By:   WHG, INC.

                                              By:   /s/ LON MCCAIN
                                                    ----------------------------
                                                    Lon McCain, Vice President,
                                                    Treasurer and Chief
                                                    Financial Officer


                                  WESTPORT FIELD SERVICES, LLC

                                  By:   WESTPORT RESOURCES CORPORATION

                                        By:   /s/ LON MCCAIN
                                              ----------------------------------
                                              Lon McCain, Vice President,
                                              Treasurer and Chief Financial
                                              Officer




                                  THE BANK OF NEW YORK,
                                  as Trustee

                                  By:    /s/ VAN K. BROWN
                                         ---------------------------------------
                                  Name:  Van K. Brown
                                  Title: Vice President


                                      S-3

<PAGE>


                                     ANNEX A

                      RESOLUTIONS OF THE BOARD OF DIRECTORS

                                       AND

                              OFFICERS' CERTIFICATE