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                                                                    EXHIBIT 4(i)

                          SECOND SUPPLEMENTAL INDENTURE

     This Second Supplemental Indenture, effective as of August 31, 2002 (this
"Second Supplemental Indenture"), among CenterPoint Energy, Inc., a Texas
corporation ("CNP"), Reliant Energy, Incorporated (formerly Houston Lighting &
Power Company), a Texas corporation ("REI"), Reliant Energy Resources Corp.
(formerly NorAm Energy Corp.), a Delaware corporation ("RERC"), and JPMorgan
Chase Bank (as successor to The Chase Manhattan Bank (National Association)), as
Trustee (the "Trustee"), supplements the Indenture dated as of March 1, 1987
between NorAm Energy Corp., a Delaware corporation and successor in interest to
Arkla, Inc. ("NorAm"), and the Trustee, as supplemented by the Supplemental
Indenture, dated as of August 6, 1997 (as supplemented, the "Indenture") among
Houston Lighting & Power Company, HI Merger, Inc., a Delaware corporation,
NorAm, and the Trustee, under which RERC's 6% Convertible Subordinated
Debentures due 2012 (the "Debentures") were issued and are outstanding.

                                    RECITALS

     WHEREAS, pursuant to the terms of the Indenture, each $50 principal amount
of the Debentures is currently convertible into $14.24 of cash (the "Cash
Consideration") and 0.65 shares of common stock, without par value, of REI ("REI
Common Stock");

     WHEREAS, pursuant to the Agreement and Plan of Merger dated as of October
19, 2001 (the "Merger Agreement") among REI, Reliant Energy MergerCo, Inc., a
Texas corporation and indirect subsidiary of CNP ("MergerCo"), and CNP, REI will
be merged with and into MergerCo, with REI to be the surviving corporation (the
"Merger");

     WHEREAS, at the effective time of the Merger (the "Effective Time"), each
outstanding share of REI Common Stock will be converted into one share of common
stock of CNP ("CNP Common Stock");

     WHEREAS, in connection with the Merger, CNP, REI and RERC have duly
determined to make, execute and deliver to the Trustee this Second Supplemental
Indenture in order to reflect the results of the Merger as required by Section
1306 of the Indenture;

     WHEREAS, Section 1306 of the Indenture requires that a Holder of a
Debenture shall have the right to convert the Debenture into the consideration
receivable upon the Merger by a holder of shares of REI Common Stock into which
the Debenture could have been converted immediately prior to the Merger; and

     WHEREAS, Section 901 of the Indenture provides that under certain
conditions RERC and the Trustee, without the consent of the Holders of
Debentures, from time to time and at any time, may enter into an indenture
supplemental to the Indenture, inter alia, to make provisions with respect to
the conversion rights of and to add covenants for the benefit of the Holders of
Debentures;

     NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH:

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     In consideration of the premises and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, and to comply with
Sections 901 and 1306 of the Indenture, the parties hereto hereby agree, for the
equal and proportionate benefit of the respective Holders from time to time of
the Debentures, as follows:

     Section 1. Defined Terms. Capitalized terms used and not otherwise defined
herein have the respective meanings assigned to such terms in the Indenture.

     Section 2. Conversion Privilege. The Holder of each Debenture outstanding
as of the Effective Time (and each subsequent Holder) shall have the right from
and after the Effective Time to convert such Debenture only into (i) 0.65 shares
of CNP Common Stock (the "Stock Consideration"), subject to the adjustments
provided for in Article Thirteen of the Indenture, (and cash in lieu of
fractional shares of CNP Common Stock) and (ii) the Cash Consideration.

     Section 3. Additional Covenants of CNP. CNP hereby (i) agrees to (A)
reserve and keep available out of its authorized but unissued capital stock,
solely for the purpose of issuance upon the conversion of Debentures as provided
in this Second Supplemental Indenture and the Indenture, a number of shares of
CNP Common Stock sufficient to issue the Stock Consideration upon the conversion
of all outstanding Debentures and (B) issue and cause to be delivered in
accordance with this Second Supplemental Indenture, the Indenture and the
Company's instructions, the Stock Consideration and the Cash Consideration upon
conversion of any Debenture and (ii) warrants that all shares of CNP Common
Stock that may be issued upon the conversion of any Debenture, when so issued,
shall be duly authorized, validly issued, fully paid and nonassessable.

     Section 4. Ratification. The Indenture as hereby supplemented is in all
respects ratified and confirmed by each of the parties hereto, and all of the
rights and powers created thereby or thereunder shall be and remain in full
force and effect.

     Section 5. Governing Law. The laws of the State of New York shall govern
this Second Supplemental Indenture without regard to principles of conflicts of
laws.

     Section 6. Successors. All agreements of the parties hereto in this Second
Supplemental Indenture shall bind their respective successors.

     Section 7. Multiple Counterparts. The parties hereto may sign multiple
counterparts of this Second Supplemental Indenture. Each signed counterpart
shall be deemed an original, but all of them together represent the same
agreement.

     Section 8. Recitals. The recitals contained in this Second Supplemental
Indenture shall be taken as the statements of CNP, REI and RERC, and the Trustee
assumes no responsibility for their correctness and makes no representations as
to the validity or sufficiency of this Second Supplemental Indenture.

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     IN WITNESS WHEREOF, the undersigned have caused this Second Supplemental
Indenture to be executed by its duly authorized officer as of the date first
above written.

                                       CENTERPOINT ENERGY, INC.

                                       By:           /s/ Rufus Scott
                                          --------------------------------------
Attest:                                   Name: Rufus Scott
                                          Title: Vice President

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

                                       RELIANT ENERGY, INCORPORATED

                                       By:          /s/ Marc Kilbride
                                          --------------------------------------
Attest:                                   Name: Marc Kilbride
                                          Title: Treasurer

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

                                       RELIANT ENERGY RESOURCES CORP.

                                       By:           /s/ Rufus Scott
                                          --------------------------------------
Attest:                                   Name: Rufus Scott
                                          Title: Vice President

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

                                       JPMORGAN CHASE BANK, Trustee

                                       By:        /s/ Gregory P. Shea
                                          --------------------------------------
Attest:                                   Name: Gregory P. Shea
                                          Title: Assistant Vice President

By:       /s/ Virginia Dominguez
   -----------------------------------
   Name: Virginia Dominguez
   Title: Trust Officer

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                                                                    EXHIBIT 4(j)

                       ASSIGNMENT AND ASSUMPTION AGREEMENT
                          FOR THE GUARANTEE AGREEMENTS

     This Assignment and Assumption Agreement (this "Agreement") is entered into
as of August 31, 2002 by and between CenterPoint Energy, Inc., a Texas
corporation (the "New Guarantor"), and Reliant Energy, Incorporated, a Texas
corporation (formerly Houston Lighting & Power Company) (the "Existing
Guarantor").

     WHEREAS, the Existing Guarantor and the Bank of New York, as Trustee (the
"Trustee"), are parties to (i) the Guarantee Agreement (relating to HL&P Capital
Trust I) dated as of February 4, 1997 (the "HL&P Trust I Guarantee") in favor of
the Holders of, and providing for the guaranty of, certain amounts relating to
the 8.125% trust preferred securities issued by HL&P Capital Trust I, a Delaware
statutory business trust (the "Preferred Securities"), and (ii) the Guarantee
Agreement (relating to HL&P Capital Trust II) dated as of February 4, 1997 (the
"HL&P Trust II Guarantee," and, together with the HL&P Trust I Guarantee, the
"Guarantees"), in favor of the Holders of, and providing for the guaranty of,
certain amounts relating to the 8.257% capital securities issued by HL&P Capital
Trust II, a Delaware statutory business trust (the "Capital Securities" and
together with the Preferred Securities, the "Securities");

     WHEREAS, pursuant to an Agreement and Plan of Merger dated as of October
19, 2001, among the Existing Guarantor, the New Guarantor and Reliant Energy
MergerCo, Inc., a Texas corporation and an indirect wholly owned subsidiary of
the New Guarantor ("MergerCo"), MergerCo will be merged with and into the
Existing Guarantor (the "Merger"), with the Existing Guarantor to be the
surviving corporation, as a result of which, at the effective time of the Merger
each share of common stock, without par value, of the Existing Guarantor will be
converted into one share of the New Guarantor's common stock and the Existing
Guarantor will become a wholly owned subsidiary of the New Guarantor;

     WHEREAS, concurrently with the Merger, the Existing Guarantor will (i)
distribute the capital stock of all of its subsidiaries, other than certain
financing subsidiaries, to the New Guarantor (the "Stock Distribution") and (ii)
convey its Texas electric generation assets and certain buildings and related
assets to indirect wholly owned subsidiaries of the New Guarantor (the "Asset
Conveyance," and together with the Merger and the Stock Distribution, the
"Restructuring");

     WHEREAS, the Restructuring is a transfer of the Existing Guarantor's
properties and assets substantially as an entirety;

     WHEREAS, the sole asset of each of HL&P Capital Trust I and HL&P Capital
Trust II is an aggregate amount of junior subordinated debentures (the
"Debentures"), issued under the Junior Subordinated Indenture dated as of
February 1, 1997 between the Existing Guarantor and The Bank of New York, as
Trustee (the "Trustee"), as supplemented by

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Supplemental Indenture No. 1 and Supplemental Indenture No. 2 both dated as of
February 1, 1997 and both between the Existing Guarantor and the Trustee (as
supplemented, the "Indenture"), equal to the aggregate liquidation amount of the
Securities and the common securities issued by each of HL&P Capital Trust I and
HL&P Capital Trust II;

     WHEREAS, as required by Section 8.1 of the Indenture, pursuant to
Supplemental Indenture No. 3 dated as of the date hereof, the New Guarantor is
assuming the obligations of the Existing Guarantor under the Debentures and the
Indenture as transferee of the Existing Guarantor's properties and assets
substantially as an entirety;

     WHEREAS, as contemplated by Section 8.1 of each of the Guarantees, the New
Guarantor is hereby assuming all obligations of the Existing Guarantor under the
Guarantees and for all purposes is becoming the "Guarantor" under the
Guarantees;

     NOW, THEREFORE, in consideration of the foregoing, and for good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties agree as follows:

     1. Assignment. The Existing Guarantor hereby assigns and delegates to the
New Guarantor all of its rights and obligations under the Guarantees.

     2. Assumption. The New Guarantor hereby accepts the foregoing assignment by
the Existing Guarantor and hereby assumes all of the Existing Guarantor's rights
and obligations under the Guarantee.

     3. Substitution and Release. The New Guarantor unconditionally and
irrevocably (i) agrees to be substituted for the Existing Guarantor under the
Guarantees and for all purposes become the "Guarantor" under the Guarantees and
(ii) releases the Existing Guarantor from all liabilities and obligations under
the Guarantees.

     4. Miscellaneous. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO THE
CONFLICTS OF LAW PRINCIPLES THEREOF. This Agreement shall inure to the benefit
of the Holders (as defined in the Guarantees) and their respective successors
and assigns, and is entered into by the New Guarantor for the express benefit of
such Holders and the Existing Guarantor.

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     IN WITNESS WHEREOF, the undersigned have caused this Agreement to be
executed by its duly authorized officer as of the date first above written.

                                       CENTERPOINT ENERGY, INC.

                                       By:         /s/ Rufus Scott
                                          --------------------------------------
                                          Name: Rufus Scott
                                          Title: Vice President

                                       RELIANT ENERGY, INCORPORATED

                                       By:        /s/ Marc Kilbride
                                          --------------------------------------
                                          Name: Marc Kilbride
                                          Title: Treasurer

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