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                                                                     EXHIBIT 3.6

                                 AMENDMENT NO. 2
                                       TO
                       LIMITED LIABILITY COMPANY AGREEMENT
                                       OF
                       EOTT ENERGY GENERAL PARTNER, L.L.C.

      This Amendment No. 2 (this "Amendment") to the Limited Liability Company
Agreement, dated as of June 27, 2001 (as amended, the "Limited Liability Company
Agreement"), of EOTT Energy General Partner, L.L.C., a Delaware limited
liability company (the "Company"), is being executed by the undersigned
authorized persons pursuant to Section 10.5 of the Limited Liability Company
Agreement.

      WHEREAS, Section 10.5 of the Limited Liability Company Agreement provides
that the Limited Liability Company Agreement may be amended with the approval of
the Board of Directors of the Company (the "Board") and the member of the
Company (the "Member"); and

      WHEREAS, the Board and the Member have each executed a written consent (i)
approving a change of the name of the Company from EOTT Energy General Partner,
L.L.C. to Link Energy General Partner LLC, and (ii) authorizing and directing
the officers of the Company to take all actions necessary or advisable to effect
the name change;

      NOW, THEREFORE, the Limited Liability Company Agreement is hereby amended
as follows:

      1.    Article 2 of the Limited Liability Company Agreement is hereby
amended by deleting Section 2.2 thereof in its entirety and replacing in lieu
thereof a new Section 2.2 reading in its entirety as follows:

            "2.2  NAME. The name of the Company is "Link Energy General Partner
LLC" and all Company business must be conducted in that name or such other names
that comply with applicable law as the Board (as defined in Section 6.1.1 of
this Agreement) may select from time to time."

      2.    All other references in the Limited Liability Company Agreement to
"EOTT Energy General Partner, L.L.C." shall be replaced with a reference to
"Link Energy General Partner LLC." All other terms and conditions of the Limited
Liability Company Agreement shall be unchanged and remain in full force and
effect. On or after the date listed below, each reference in the Limited
Liability Company Agreement to "this Agreement," "hereunder," "hereof," "herein"
or words of like import, and any reference to the Limited Liability Company
Agreement in any certificate or document delivered in connection therewith,
shall mean and be a reference to the Limited Liability Company Agreement as
amended hereby.

      3.    All capitalized terms used in this Amendment but not defined herein
shall have the meanings ascribed to such terms in the Limited Liability Company
Agreement.
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                                                                     EXHIBIT 3.6

      4.    This Amendment shall be governed by and construed in accordance with
the laws of the State of Delaware.

      IN WITNESS WHEREOF, the undersigned authorized persons have executed this
Amendment to the Limited Liability Company Agreement on behalf of the Member and
the Board effective as of the first day of October, 2003.

                                   MEMBER:

                                   LINK ENERGY LLC

                                   /s/ THOMAS M. MATTHEWS
                                   ---------------------------------------------
                                   Thomas M. Matthews
                                   Chief Executive Officer

                                   BOARD:

                                   /s/ THOMAS M. MATTHEWS
                                   ---------------------------------------------
                                   Thomas M. Matthews

                                   /s/ H. KEITH KAELBER
                                   ---------------------------------------------
                                   H. Keith Kaelber

                                   /s/ DANA R. GIBBS
                                   ---------------------------------------------
                                   Dana R. Gibbs