Document:

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                                                                 EXHIBIT 4(h)(4)

                            CENTERPOINT ENERGY, INC.
                   (Successor to Reliant Energy, Incorporated)

                                       To

                    JPMORGAN CHASE BANK, NATIONAL ASSOCIATION
            (Successor to Chase Bank of Texas, National Association)

                                     Trustee

                                   ----------

                          SUPPLEMENTAL INDENTURE No. 3

                          Dated as of December 28, 2005

                                   ----------

      2.0% Zero-Premium Exchangeable Subordinated Notes due 2029 (ZENS(SM))

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(SM) Service Mark of Goldman, Sachs & Co.

<PAGE>

                            CENTERPOINT ENERGY, INC.

                          SUPPLEMENTAL INDENTURE NO. 3

      2.0% Zero-Premium Exchangeable Subordinated Notes due 2029 (ZENS(SM))

     SUPPLEMENTAL INDENTURE No. 3, dated as of December 28, 2005, between
CENTERPOINT ENERGY, INC. (successor to Reliant Energy, Incorporated), a Texas
corporation (the "Company"), and JPMORGAN CHASE BANK, NATIONAL ASSOCIATION
(successor to Chase Bank of Texas, National Association), a national banking
association, as Trustee (the "Trustee").

                                    RECITALS

     The Company has heretofore executed and delivered to the Trustee a
Subordinated Indenture, dated as of September 1, 1999 (the "Original Indenture"
and, as previously and hereby supplemented and amended, the "Indenture"),
providing for the issuance from time to time of one or more series of the
Company's Securities.

     Pursuant to the terms of the Indenture, the Company provided for the
establishment of a series of Securities designated as the "2% Zero-Premium
Exchangeable Subordinated Notes due 2029" (the "ZENS"), the form and substance
of the ZENS and the terms, provisions and conditions thereof in Supplemental
Indenture No. 1, dated as of September 1, 1999, between the Company and the
Trustee.

     Section 307 of the Indenture provides that the Company may at any time
designate additional Paying Agents or rescind the designation of any Paying
Agent.

     Subparagraph (5) of Section 901 of the Indenture provides that the Company
and the Trustee may enter into an indenture supplemental to the Indenture to add
to, change or eliminate any of the provisions of the Indenture if such action
does not adversely affect the interests of any Holders.

     For and in consideration of the premises and the issuance of the series of
Securities provided for herein, it is mutually covenanted and agreed, for the
equal and proportionate benefit of the Holders of the Securities of such series,
as follows:

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                                   ARTICLE ONE

                            Relation to the Indenture

     Section 101. Relation to the Indenture. This Supplemental Indenture No. 3
constitutes an integral part of the Indenture.

                                   ARTICLE TWO

                           Designation of Paying Agent

     Section 201. Designation of Paying Agent. JPMorgan Chase Bank, National
Association is hereby designated as the Paying Agent on the ZENS. The
designation of CenterPoint Energy, Inc. as the Paying Agent on the ZENS is
hereby rescinded.

                                  ARTICLE THREE

                            Miscellaneous Provisions

     Section 301. The Indenture, as supplemented and amended by this
Supplemental Indenture No. 3, is in all respects hereby adopted, ratified and
confirmed.

     Section 302. This Supplemental Indenture No. 3 may be executed in any
number of counterparts, each of which shall be an original, but such
counterparts shall together constitute but one and the same instrument. This
Supplemental Indenture No. 3 shall be deemed part of the Indenture in the manner
and to the extent herein and therein provided.

     Section 303. THIS SUPPLEMENTAL INDENTURE NO. 3 AND EACH ZENS SHALL BE
DEEMED TO BE A CONTRACT MADE UNDER THE LAWS OF THE STATE OF NEW YORK AND SHALL
BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW
YORK WITHOUT REGARD TO CONFLICTS OF LAWS PRINCIPLES THEREOF.

<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture No. 3 to be duly executed, as of the day and year first written above.

                                        CENTERPOINT ENERGY, INC.

                                        By: /s/ Marc Kilbride
                                            ------------------------------------
                                        Name: Marc Kilbride
                                        Title: Vice President and Treasurer

Attest: /s/ Richard B. Dauphin
        -----------------------------
Name: Richard B. Dauphin
Title: Assistant Corporate Secretary

(SEAL)

                                        JPMORGAN CHASE BANK, NATIONAL
                                        ASSOCIATION, as Trustee

                                        By: /s/ Carol Logan
                                            ------------------------------------
                                        Name: Carol Logan
                                        Title: Vice President

(SEAL)<PAGE>
                                                               Exhibit 10(t)(19)

                    CENTERPOINT ENERGY, INC. RETIREMENT PLAN

               (As Amended and Restated Effective January 1, 1999)

                              Thirteenth Amendment

          CenterPoint Energy, Inc., a Texas corporation, having reserved the
right under Section 15.1 of the CenterPoint Energy, Inc. Retirement Plan, as
amended and restated effective as of January 1, 1999, and as thereafter amended
(the "Plan"), under Section 15.1 of the Plan, does hereby amend the Plan,
effective as of January 1, 2006, as follows:

     1. Article VIII of the Plan is hereby amended to add the following new
Section 8.9 thereto:

          "8.9 2006 Southern Gas Involuntary Separation Benefit: A Member who
     (i) is an Eligible Southern Gas Employee (as defined below), (ii) has
     attained at least age 55 and completed at least 5 years of Service as of
     his Termination Date (as defined below), and (iii) qualifies for a benefit
     under a Company involuntary severance benefits plan (a 'Southern Gas
     Severance Plan'), which provides for this benefit for an Eligible Southern
     Gas Employee who is involuntarily terminated during the Severance Period
     (as defined below), and who satisfies all requirements for this benefit
     under the applicable Southern Gas Severance Plan, shall be eligible,
     subject to his timely execution and delivery without subsequent revocation
     of the waiver and release, and his timely execution and delivery of any
     election or other documents, required under the applicable Southern Gas
     Severance Program, to receive a Pension commencing on or after his
     Termination Date equal to the normal or early retirement Pension for which
     the Member is eligible (or, in the case of an Eligible Southern Gas
     Employee who is on Disability Leave of Absence, would have been eligible
     had his employment continued through the period of disability and
     terminated, and his benefit accruals under the Plan shall cease, on his
     Termination Date), calculated as set forth in Section 8.1 or 8.2, but
     adding three (3) deemed years to the Member's age and three (3) deemed
     years to the Member's Service as applicable to the specific benefit
     formulas under the Plan (including for purposes of the Grandfathered
     Benefit under Section 7.6), except with respect to the Actuarial Equivalent
     calculations under Article XI.

          For purposes of this Section 8.9,

               (a) An 'Eligible Southern Gas Employee' means a Member (i) who
          was a nonexempt Employee of CenterPoint Energy Southern Gas
          Operations, a division of CenterPoint Energy Resources Corp., a wholly

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          owned subsidiary of the Company, and any successor to CenterPoint
          Energy Southern Gas Operations ('Southern Gas'), (ii) whose employment
          with Southern Gas was involuntary terminated during the Severance
          Period, and (iii) who is not subsequently employed by the Employer or
          any Affiliate prior to his Termination Date.

               (b) The 'Severance Period' means the period prescribed in the
          Southern Gas Severance Plan; provided, however, that such period shall
          not commence prior to January 1, 2006, and shall not extend beyond
          December 31, 2006.

               (c) The 'Termination Date' means an Eligible Southern Gas
          Employee's involuntary termination of Service date.

               (d) To the extent applicable, a Member's Compensation, as
          provided in Section 1.16, in effect on his Termination Date shall be
          deemed to continue unchanged during his deemed three (3) years of
          Service.

          The foregoing notwithstanding, the enhanced benefits provided under
     this Section are subject to compliance with the non-discrimination
     requirements under Section 401(a)(4) of the Code and, to the extent the
     Committee determines in its sole discretion is necessary to satisfy such
     requirements, such benefit may be reduced or otherwise adjusted."

     2. Article VIII of the Plan is hereby amended to add the following new
Section 8.10 thereto:

          "8.10 2006 Voluntary Early Retirement Program: A Member who is an
     Eligible VERP Employee (as defined below) and who has attained at least age
     55 and completed at least 5 years of Service as of February 28, 2006, may
     elect to participate in the Company's 2006 Voluntary Early Retirement
     Programs for Southern Gas Operations Employees, CenterPoint Energy Service
     Information Technology Employees and Finance and Regulatory, Regulated
     Operations Employees (collectively, the '2006 Program'). Any election to
     participate in the 2006 Program shall be made in writing between January 5,
     2006 and February 28, 2006 (or within 50 days of receipt of the 2006
     Program materials, including the related form of waiver and release, if
     later), in the form and manner prescribed by the Committee, including
     subsequent execution of such waiver and release, as a condition of
     eligibility for the 2006 Program. Except as provided below, any Eligible
     VERP Employee who elects to participate in the 2006 Program shall
     voluntarily terminate his Service on February 28, 2006, or such earlier
     date after January 5, 2006, but prior to February 28, 2006, as agreed to by
     the Company and the Eligible VERP Employee (as applicable, his 'Termination
     Date'), and shall be eligible to elect to receive the 'Voluntary Early
     Pension' (as described below) in

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     lieu of any other pension hereunder, which shall be payable in accordance
     with the provisions of Article XI (including the optional forms of
     payment), effective as of the Termination Date. Any Eligible VERP Employee
     who elects to participate in the 2006 Program and who, at the request of
     his Employer, elects to extend his Service beyond the Termination Date to a
     later termination date based on a specific business need of his Employer,
     shall receive the Voluntary Early Pension commencing no earlier than the
     first day of the month coincident with or next following his actual
     termination of Service and payable in accordance with the provisions of
     Article XI in effect as of such later date (with such later date, his
     Termination Date).

          An Eligible VERP Employee who has elected to participate in the 2006
     Program, subject to his execution and delivery without subsequent
     revocation of the waiver and release required under the 2006 Program, shall
     be eligible to receive a Voluntary Early Pension commencing on his
     Termination Date equal to the normal or early retirement Pension for which
     the Member is eligible (or, in the case of an Eligible VERP Employee who is
     on Disability Leave of Absence, would have been eligible had his employment
     continued through the period of disability and terminated, and his benefit
     accruals under the Plan shall cease, on the Termination Date), calculated
     as set forth in Section 8.1 or 8.2, but adding three (3) deemed years to
     the Member's age and three (3) deemed years to the Member's Service for all
     purposes under the Plan (including for purposes of the Grandfathered
     Benefit under Section 7.6), other than Actuarial Equivalent calculations
     under Article XI.

          For purposes of this Section 8.10,

               (a) An 'Eligible VERP Employee' is a Member who

                    (i) on January 5, 2006, is an (1) active, exempt Employee of
               CenterPoint Energy Southern Gas Operations, a division of
               CenterPoint Energy Resources Corp., a wholly owned subsidiary of
               the Company, (2) active information technology employee of
               CenterPoint Energy Service Company, LLC, a wholly owned
               subsidiary of the Company, or (3) active finance and regulatory,
               regulated operations employee of the Company or any Affiliate;

                    (ii) is not an officer of the Company or any Affiliate at
               the vice president level or above; and

                    (iii) is not subsequently employed by the Employer or any
               Affiliate prior to his Termination Date.

               (b) To the extent applicable, a Member's Compensation, as
          provided in Section 1.16, in effect on his Termination Date shall be

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          deemed to continue unchanged during his deemed three (3) years of
          Service.

          The foregoing notwithstanding, the enhanced benefits provided under
     this Section are subject to compliance with the non-discrimination
     requirements under Section 401(a)(4) of the Code and, to the extent the
     Committee determines in its sole discretion is necessary to satisfy such
     requirements, such benefit may be reduced or otherwise adjusted."

          IN WITNESS WHEREOF, CenterPoint Energy, Inc. has caused these presents
to be executed by its duly authorized officer in a number of copies, all of
which shall constitute one and the same instrument, which may be sufficiently
evidenced by any executed copy hereof, on this 6th day of February, 2006, but
effective as of the January 1, 2006.

                                        CENTERPOINT ENERGY, INC.

                                        By /s/ David McClanahan
                                           -------------------------------------
                                           David McClanahan
                                           President and Chief Executive Officer

ATTEST:

/s/ Richard Dauphin
-------------------------------------
Richard Dauphin
Assistant Secretary

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