<PAGE>   1
                                                                    EXHIBIT 4.4



                          FIRST SUPPLEMENTAL INDENTURE


         FIRST SUPPLEMENTAL INDENTURE, dated as of __________ ___, 200_ (this
"FIRST SUPPLEMENTAL INDENTURE"), between New NiSource Inc., a Delaware
corporation (the "COMPANY"), and The Chase Manhattan Bank, as trustee (the
"TRUSTEE"), under the Indenture dated as of _______ __, 200_ between the Company
and the Trustee (the "INDENTURE").

         WHEREAS, the Company executed and delivered the Indenture to the
Trustee to provide for the issuance from time to time of the Company's unsecured
debentures, notes or other evidences of indebtedness (collectively the
"SECURITIES," and individually, a "SECURITY") to be issued in one or more series
as might be determined by the Company under the Indenture, in an unlimited
aggregate principal amount which may be authenticated and delivered as provided
in the Indenture;

         WHEREAS, pursuant to the terms of the Indenture, the Company desires to
provide for the establishment of a new series of Securities to be known as the
Senior Debentures due 200_ (the "DEBENTURES"), the form and substance of such
Debentures and their terms, provisions and conditions to be as set forth in the
Indenture and this First Supplemental Indenture;

         WHEREAS, the Company has requested that the Trustee execute and deliver
this First Supplemental Indenture, all requirements necessary to make this First
Supplemental Indenture a valid instrument in accordance with its terms (and to
make the Debentures, when executed by the Company and authenticated and
delivered by the Trustee, the valid obligations of the Company) have been
performed, and the execution and delivery of this First Supplemental Indenture
has been duly authorized in all respects;

         NOW, THEREFORE, in consideration of the purchase and acceptance of the
Debentures by the Holders, and for the purpose of setting forth, as provided in
the Indenture, the form and substance of the Debentures and their terms,
provisions and conditions, the Company covenants and agrees with the Trustee as
follows:


                                   ARTICLE II
                                   DEFINITIONS

         SECTION 1.1 DEFINITION OF TERMS. Unless the context otherwise requires:

         (a) a term not defined in this First Supplemental Indenture that is
defined in the Indenture has the same meaning when used in this First
Supplemental Indenture;

         (b) a term defined anywhere in this First Supplemental Indenture has
the same meaning throughout;

         (c) the singular includes the plural and vice versa;

         (d) a reference to a Section or an Article is to a Section or an
Article of this First Supplemental Indenture unless another document is
expressly identified as part of the reference;

         (e) headings are for convenience of reference only and do not affect
interpretation;



<PAGE>   2






         (f) the following terms have the meanings given to them in the Purchase
Contract Agreement: (i) Cash Settlement; (ii) Change in Control; (iii) Corporate
Units; (iv) Purchase Contract; (v) Purchase Contract Settlement Date; (vi)
Remarketing Agreement; and (vii) Remarketing Date; and

         (g) the following terms have the meanings given to them in this Section
1.1(g): "BUSINESS DAY" means any day other than a Saturday or Sunday or a day on
which banking institutions in New York City are authorized or required by law or
executive order to remain closed or a day on which the principal office of the
Trustee is closed for business.

         "APPLICABLE MARGIN" means the spread determined as set forth below,
based on the prevailing rating of the remarketed Debentures in effect at the
close of business on the Business Day immediately preceding the date of a Failed
Remarketing (as defined in Section 7.1(h)):

<TABLE>
<CAPTION>

     Prevailing Rating                                      Spread
     -----------------                                      ------
     <S>                                                    <C>
     AS/ "As" ......................................         ___%
     A/ "a" ........................................         ___%
     BBB/ "Baa" ....................................         ___%
     Below BBB/ "Baa" ..............................         ___%
</TABLE>



For purposes of this definition, the "prevailing rating" of the remarketed
Debentures shall be:

          (i) AS/ "As" if the remarketed Debentures have a credit
     rating of AS- or better by S&P and "Aa3" or better by Moody's or
     the equivalent of such ratings by such agencies or a substitute
     rating agency or substitute rating agencies selected by the
     Remarketing Agent;

          (ii) if not under clause (i) above, then A/ "a" if the
     remarketed Debentures have a credit rating of A- or better by S&P
     and "A3" or better by Moody's or the equivalent of such ratings
     by such agencies or a substitute rating agency or substitute
     rating agencies selected by the Remarketing Agent;


          (iii) if not under clauses (i) or (ii) above, then BBB/ "Baa" if
     the remarketed Debentures have a credit rating of BBB- or better by
     S&P and "Baa3" or better by Moody's or the equivalent of such ratings
     by such agencies or a substitute rating agency or substitute rating
     agencies selected by the Remarketing Agent; or

          (iv) if not under clauses (i) - (iii) above, then Below BBB/
     "Baa."

Notwithstanding the foregoing, (A) if (i) the credit rating of the remarketed
Debentures by S&P shall be on the "Credit Watch" of S&P with a designation of
"negative implications" or "developing," or (ii) the credit rating of the
remarketed Debentures by Moody's shall be on the "Corporate Credit Watch List"
of Moody's with a designation of "downgrade" or "uncertain," or, in each case,
on any successor list of S&P or Moody's with a comparable designation, the
prevailing ratings of the remarketed Debentures shall be deemed to be within a
range one full level lower in the above table than those actually assigned to
the remarketed Debentures by Moody's and S&P and (B) if the remarketed
Debentures are rated by only one rating agency on or before the Remarketing
Date, the prevailing rating shall at all times be determined without reference
to the rating of any other rating agency; provided, that if no such rating
agency shall have in effect a rating for the remarketed Debentures and the
Remarketing Agent is unable to identify a substitute rating agency or rating
agencies, the prevailing rating shall be Below BBB/ "baa."

          "INTEREST RATE" has the meaning specified in Section 7.1(f), 7.1(g) or
     7.1(h), as applicable.


                                       2
<PAGE>   3


                  "PURCHASE CONTRACT AGREEMENT" means the Purchase Contract
Agreement dated as of _________ __, 200_, between the Company and The Chase
Manhattan Bank, as Purchase Contract Agent.

                  "REMARKETING" means the operation of the procedures for
remarketing specified in Article VII.

                  "REMARKETING AGENT" shall mean Credit Suisse First Boston
Corporation or any successor Remarketing Agent engaged by the Company.

                  "REMARKETING DATE" means the third Business Day prior to the
Purchase Contract Settlement Date.

                  "TWO-YEAR BENCHMARK TREASURY RATE" means the bid side rate
displayed at 10:00 a.m., New York City time, on the third business day preceding
the Purchase Contract Settlement Date for direct obligations of the United
States (which may be obligations traded on a when-issued basis only) having a
maturity comparable to the remaining term to maturity of the remarketed
Debentures, as agreed upon by the Company and the Remarketing Agent. The rate
for the Two-Year Benchmark Treasury will be the bid side rate displayed at 10:00
A.M., New York City time, on the third Business Day immediately preceding the
Purchase Contract Settlement Date in the Telerate system (or if the Telerate
system is (A) no longer available on the third Business Day immediately
preceding the Purchase Contract Settlement Date or (B) in the opinion of the
Remarketing Agent (after consultation with the Company) is no longer an
appropriate system from which to obtain such rate, such other nationally
recognized quotation system as, in the opinion of the Remarketing Agent (after
consultation with the Company) is appropriate). If such rate is not so
displayed, the rate for the Two-Year Benchmark Treasury shall be, as calculated
by the Remarketing Agent, the yield to maturity for the Two-Year Benchmark
Treasury, expressed as a bond equivalent on the basis of a year of 365 or 366
days, as applicable, and applied on a daily basis, and computed by taking the
arithmetic mean of the secondary market bid rates, as of 10:30 A.M., New York
City time, on the third Business Day immediately preceding the Purchase Contract
Settlement Date of three leading United States government securities dealers
selected by the Remarketing Agent (after consultation with the Company) (which
may include the Remarketing Agent or one of its affiliates).


                                   ARTICLE II
                     TERMS AND CONDITIONS OF THE DEBENTURES

         SECTION 2.1 DESIGNATION, DENOMINATION AND PRINCIPAL AMOUNT. There is
authorized a series of Securities designated as "Senior Debentures due 200_,"1/
limited in aggregate principal amount to $___________, in the denomination of
$[2.60].

         SECTION 2.2 MATURITY. The Stated Maturity is ___________ __, 200_.2/

         SECTION 2.3 GLOBAL DEBENTURES. The Debentures in certificated form may
be presented to the Trustee in exchange for a Global Security in an aggregate
principal amount equal to all Outstanding Debentures (a "GLOBAL DEBENTURE"). The
Depositary for the Debentures will be The Depository Trust Company. The Global
Debentures will be registered in the name of the Depositary or its nominee, Cede
& Co., and delivered by the Trustee to the Depositary or a custodian appointed
by the Depositary for crediting to the accounts of its participants pursuant to
the instructions of the Trustee. The Company upon any such presentation shall
execute a Global Debenture in such aggregate principal amount and deliver the
same to the Trustee for authentication and delivery in accordance with the
Indenture and this First Supplemental Indenture. Payments on the Debentures
issued as a Global Debenture will be made to the Depositary or its nominee.


--------
     1/ The sixth year after the Effective Time.

     2/ A date that is six years after the Effective Time.


                                       3
<PAGE>   4






         SECTION 2.4 INTEREST.

         (a) The Debentures shall not bear interest from the date they are
issued and delivered until the Purchase Contract Settlement Date, and shall bear
interest at the Interest Rate from that date until principal is paid, payable
quarterly in arrears on the Interest Payment Dates, which shall be ___________,
_____________, ___________ and _____________ of each year, commencing
__________, 200_.3/

         (b) Interest not paid on the scheduled payment date shall accumulate
and compound quarterly at the Interest Rate from the scheduled payment date
until paid.

         (c) The Regular Record Dates for the Debentures shall be (i) as long as
the Debentures are represented by a Global Debenture, the Business Day preceding
each Interest Payment Date or (ii) if the Debentures are issued in certificated
form, the 15th Business Day prior to each Interest Payment Date.

         (d) The Debentures outstanding will bear interest on and after the
Purchase Contract Settlement Date at the Interest Rate, to be set on the third
Business Day preceding the Purchase Contract Settlement Date. The Interest Rate
will be equal to the rate per annum that results from the Remarketing pursuant
to Article VII; provided, that if a Failed Remarketing occurs, the Interest Rate
will be equal to (i) the Two-Year Benchmark Treasury Rate plus (ii) the
Applicable Margin.

         (e) The amount of interest payable on the Debentures for any period
will be computed (i) for any full quarterly period on the basis of a 360-day
year of twelve 30-day months and (ii) for any period shorter than a full
quarterly period, on the basis of a 30-day month and, for any period less than a
month, on the basis of the actual number of days elapsed per 30-day month. If
any date on which interest is payable on the Debentures is not a Business Day,
then payment of the interest payable on such date will be made on the next day
that is a Business Day (and without interest or other payment in respect of any
such delay), except that, if such Business Day is in the next calendar year,
then such payment will be made on the preceding Business Day.

         SECTION 2.5 REDEMPTION.

         (a) The Debentures are not subject to redemption at the option of the
Company prior to their Stated Maturity.

         (b) The Debentures are not subject to redemption prior to their Stated
Maturity through the operation of a sinking fund.

         SECTION 2.6 [INTENTIONALLY OMITTED].

         SECTION 2.7 PAYING AGENT; SECURITY REGISTRAR. If the Debentures are
issued in certificated form, the Paying Agent and the Security Registrar for the
Debentures shall be the Corporate Trust Office of the Trustee.

--------
    3/ The first such date occurring after the date that is four years after the
       Effective Time.



                                       4
<PAGE>   5






                                   ARTICLE III
                                FORM OF DEBENTURE

         SECTION 3.1. FORM OF DEBENTURE. The Debentures and the Trustee's
Certificate of Authentication to be endorsed on them are to be substantially in
the following forms:

                           (FORM OF FACE OF DEBENTURE)

[IF THE DEBENTURE IS TO BE A GLOBAL DEBENTURE, INSERT: This Debenture is a
Global Security within the meaning of the Indenture referred to below and is
registered in the name of The Depository Trust Company, a New York corporation
(the "DEPOSITARY"), or a nominee of the Depositary. This Debenture is
exchangeable for Debentures registered in the name of a person other than the
Depositary or its nominee only in the limited circumstances described in the
Indenture, and no transfer of this Debenture (other than a transfer of this
Debenture as a whole by the Depositary to a nominee of the Depositary or by a
nominee of the Depositary to the Depositary or another nominee of the
Depositary) may be registered except in limited circumstances.

Unless this Debenture is presented by an authorized representative of the
Depositary to the issuer or its agent for registration of transfer, exchange or
payment, and any Debenture issued is registered in the name of Cede & Co. or
such other name as requested by an authorized representative of the Depositary,
and any payment hereon is made to Cede & Co., or to such other entity as is
requested by an authorized representative of the Depositary), and, except as
otherwise provided in the Indenture, ANY TRANSFER, PLEDGE OR OTHER USE HEREOF
FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL since the registered
owner hereof, Cede & Co., has an interest herein.]


No._______1________

$__________

CUSIP No. _________


                           SENIOR DEBENTURE DUE 200_ 4/









-------
    4/ The sixth year after the Effective Time.





                                       5
<PAGE>   6




         New NiSource Inc., an Indiana corporation (the "COMPANY", which term
includes any successor corporation under the Indenture referred to below), for
value received, promises to pay to CEDE & CO., or registered assigns, the
principal sum of $__________ Dollars on ____________, 200_5/ (the "STATED
MATURITY"), and to pay interest on said principal sum from _____________,
200_,6/ or from the most recent interest payment date (each such date, an
"INTEREST PAYMENT DATE") to which interest has been paid or duly provided for,
quarterly in arrears on ________, __________, __________ and ____________ of
each year, commencing on __________, 200_,7/ at the Interest Rate, until the
principal of this Debenture shall have become due and payable, and on any
overdue principal and premium, if any, and (without duplication and to the
extent that payment of such interest is enforceable under applicable law) on any
overdue installment of interest at the same rate per annum compounded quarterly.
The amount of interest payable for any period will be computed (1) for any full
quarterly period on the basis of a 360-day year of twelve 30-day months and (2)
for any period shorter than a full quarterly period, on the basis of a 30-day
month and, for any period less than a month, on the basis of the actual number
of days elapsed per 30-day month. If any date on which interest is payable is
not a Business Day, then payment of the interest payable on such date will be
made on the next day that is a Business Day (and without any interest or other
payment in respect of such delay), except that, if such Business Day is in the
next calendar year, then such payment will be made on the preceding Business
Day. The interest installment so payable, and punctually paid or duly provided
for, on any Interest Payment Date will, as provided in the Indenture referred to
on the reverse side of this Debenture, be paid to the person in whose name this
Debenture (or one or more Predecessor Securities, as defined in the Indenture)
is registered at the close of business on the Regular Record Date for such
interest installment, which, if this Debenture is a Global Security, shall be
the close of business on the Business Day preceding such Interest Payment Date
or, if this Debenture is not a Global Security, shall be the close of business
on the 15th Business Day preceding such Interest Payment Date; provided, that
interest paid at maturity shall be paid to the Person to whom principal is paid.
Any such interest installment not punctually paid or duly provided for shall
cease to be payable to the registered Holder on such Regular Record Date and may
be paid to the Person in whose name this Debenture (or one or more Predecessor
Securities) is registered at the close of business on a special record date to
be fixed by the Trustee referred to on the reverse side of this Debenture for
the payment of such defaulted interest, notice of which shall be given to the
registered Holders of the Debentures not less than 10 days prior to such special
record date, or may be paid at any time in any other lawful manner not
inconsistent with the requirements of any securities exchange on which the
Debentures may be listed, and upon such notice as may be required by such
exchange, all as more fully provided in the Indenture. The principal of and
interest on this Debenture shall be payable at the office or agency of the
Trustee maintained for that purpose in any coin or currency of the United States
of America that at the time of payment is legal tender for payment of public and
private debts; provided, that payment of interest may be made at the option of
the Company by check mailed to the registered Holder at such address as shall
appear in the Security Register.

         This Debenture is, to the extent provided in the Indenture, senior and
unsecured and will rank in right of payment on a parity with all other senior
unsecured obligations of the Company.

         Unless the Certificate of Authentication on this Debenture has been
executed by the Trustee, this Debenture shall not be entitled to any benefit
under the Indenture or be valid or obligatory for any purpose. The provisions of
this Debenture are continued on the reverse side, and such continued provisions
shall for all purposes have the same effect as though fully set forth at this
place.

-------

    5/ The date that is six years after the Effective Time.

    6/ The date that is four years after the Effective Time.

    7/ The first such date occurring after the date that is four years
       after the Effective Time.






                                       6
<PAGE>   7






         IN WITNESS WHEREOF, the Company has caused this instrument to be
executed.


                                              New NiSource Inc.

                                              By:
                                                -------------------------------

Attest:

By:
  --------------------------------
         Secretary

                          CERTIFICATE OF AUTHENTICATION

This is one of the Securities of the series referred to in the within-mentioned
Indenture.


Dated:                                     The Chase Manhattan Bank, as Trustee
     ------------
                                                     By:
                                                       ------------------------
                                                           Authorized Officer



         This Debenture is one of a duly authorized series of Securities of the
Company (referred to as the "DEBENTURES"), all issued under and pursuant to an
Indenture dated as of ______, 200_, duly executed and delivered between New
NiSource Inc. (the "COMPANY") and The Chase Manhattan Bank, as Trustee (the
"TRUSTEE"), as supplemented by the First Supplemental Indenture to the Indenture
dated as of _______ 200_, between the Company and the Trustee (such Indenture as
so supplemented, the "INDENTURE"), to which Indenture, and all indentures
supplemental to it, reference is made for a description of the rights,
limitations of rights, obligations, duties and immunities of the Trustee, the
Company and the Holders of the Debentures. By the terms of the Indenture, the
Securities are issuable in series that may vary as to amount, date of maturity,
rate of interest and in other respects as provided in the Indenture. This series
of Securities is limited in aggregate principal amount to $______________.

         All terms used in this Debenture that are defined in the Indenture
shall have the meanings assigned to them in the Indenture.

         This Debenture is not subject to redemption at the option of the
Company prior to its Stated Maturity.

         This Debenture is not subject to redemption prior to its Stated
Maturity through the operation of a sinking fund.

         If an Event of Default shall have occurred and be continuing, the
principal of all of the Debentures may be declared, and upon such declaration
shall become, due and payable, in the manner, with the effect and subject to the
conditions provided in the Indenture.


                                       7
<PAGE>   8


         The Indenture contains provisions permitting the Company and the
Trustee, without the consent of any Holder, to execute supplemental indentures
modifying certain provisions of the Indenture and, with the consent of the
Holders of not less than a majority in aggregate principal amount of the
Debentures and all other series of Securities affected at the time Outstanding,
as defined in the Indenture, to execute supplemental indentures for the purpose
of adding any provisions to or changing in any manner or eliminating any of the
provisions of the Indenture or of any supplemental indenture or of modifying in
any manner the rights of the Holders of the Debentures; provided, that no such
supplemental indenture may, without the consent of the Holder of each
outstanding Debenture, among other things, (i) change the stated maturity of the
principal of, or any installment of interest on, any Debenture, (ii) reduce the
principal amount of, or the rate of interest on, the Debentures, (iii) impair
the right to institute suit for the enforcement of any such payment on or after
the stated maturity of the Debentures or (iv) reduce the above-stated percentage
of principal amount of Debentures, the consent of the Holders of which is
required to modify or amend the Indenture, to consent to any waiver under the
Indenture, or to approve any supplemental indenture. The Indenture also contains
provisions permitting the Holders of a majority in aggregate principal amount of
the Debentures at the time Outstanding affected thereby, on behalf of all of the
Holders of the Debentures, to waive any past default in the performance of any
of the covenants contained in the Indenture, or established pursuant to the
Indenture with respect to the Debentures, and its consequences, except a default
in the payment of the principal of or interest on any of the Debentures (unless
cured as provided in the Indenture) or in respect of a covenant or provision
that cannot be modified or amended without the consent of the Holders of each
Debenture then Outstanding. Any such consent or waiver by a registered Holder of
this Debenture (unless revoked as provided in the Indenture) shall be conclusive
and binding upon such Holder and upon all future Holders and owners of this
Debenture and of any Debenture issued in exchange for it or in place of it
(whether by registration of transfer or otherwise), irrespective of whether or
not any notation of such consent or waiver is made upon this Debenture.

         No reference in this Debenture to the Indenture and no provision of
this Debenture or of the Indenture shall alter or impair the obligation of the
Company, which is absolute and unconditional, to pay the principal of and
premium, if any, and interest on this Debenture at the time and place and at the
rate and in the money prescribed in this Debenture.

         As provided in, and subject to certain limitations set forth in, the
Indenture, this Debenture is transferable by the registered Holder on the
Security Register of the Company, upon surrender of this Debenture for
registration of transfer at the office or agency of the Company in the City and
State of New York accompanied by a written instrument or instruments of transfer
in form satisfactory to the Company or the Trustee duly executed by the
registered Holder or his attorney duly authorized in writing, after which one or
more new Debentures of authorized denominations and for the same aggregate
principal amount will be issued to the designated transferee or transferees. No
service charge will be made for any such transfer, but the Company may require
payment of a sum sufficient to cover any tax or other governmental charge
payable in relation to such transfer.

         Prior to due presentment for registration of transfer of this
Debenture, the Company, the Trustee, any paying agent and any Security Registrar
may deem and treat its registered holder as the absolute owner of this Debenture
(whether or not this Debenture shall be overdue and notwithstanding any notice
of ownership or writing on this Debenture made by anyone other than the Security
Registrar) for the purpose of receiving payment of or on account of the
principal of and premium, if any, and interest due on this Debenture and for all
other purposes, and neither the Company nor the Trustee nor any paying agent nor
any Security Registrar shall be affected by any notice to the contrary.

         No recourse shall be had for the payment of the principal of or the
interest on this Debenture, or for any claim based on this Debenture, or
otherwise in respect of this Debenture, or based on or in respect of the
Indenture, against any incorporator, stockholder, officer or director, past,
present or future, as such, of the Company or of any predecessor or successor
corporation, whether by virtue of any constitution, statute or rule of law, or
by the enforcement of any assessment or penalty or otherwise, all such liability
being, by the acceptance of this Debenture and as part of the consideration for
the issuance of this Debenture, expressly waived and released.

         The Indenture imposes certain limitations on the ability of the Company
to, among other things, merge, consolidate or sell, assign, transfer or lease
all or substantially all of its properties or assets. Such covenants and
limitations are subject to a number of important qualifications and exceptions.
The Company must report periodically to the Trustee on compliance with the
covenants in the Indenture.

                                       8
<PAGE>   9

         The Debentures of this series are issuable only in registered form
without coupons in denominations of $[2.60] and any integral multiple of such
amount. As provided in the Indenture and subject to certain limitations in this
Debenture and in the Indenture set forth, Debentures of this series so issued
are exchangeable for a like aggregate principal amount of Debentures of this
series of a different authorized denomination, as requested by the Holder
surrendering the same.

                                   ARTICLE IV
                                    EXPENSES

         SECTION 4.1 PAYMENT OF EXPENSES. The Company will pay for all costs and
expenses relating to the offering, sale and issuance of the Debentures,
including compensation of the Trustee under the Indenture in accordance with the
provisions of Section 607 of the Indenture.


                                    ARTICLE V
                                    COVENANTS

         SECTION 5.1 COVENANT TO LIST ON EXCHANGE. The Company will use its best
efforts to list the Corporate Units on the New York Stock Exchange and to
maintain such listing.


                                   ARTICLE VI
                          ORIGINAL ISSUE OF DEBENTURES

         SECTION 6.1 ORIGINAL ISSUE OF DEBENTURES. Debentures in an aggregate
principal amount of up to $____________ may, upon execution of this First
Supplemental Indenture, be executed by the Company and delivered to the Trustee
for authentication, and the Trustee shall thereupon authenticate and deliver
said Debentures upon receipt of a Company Order, without any further action by
the Company.


                                   ARTICLE VII
                                   REMARKETING

         SECTION 7.1 REMARKETING.

         (a) The Company shall request, not later than 15 nor more than 30
calendar days prior to the Remarketing Date, that the Depositary notify the
Holders of the Debentures and the holders of the Corporate Units of the
Remarketing and of the procedures that must be followed if a holder of Corporate
Units wishes to make a Cash Settlement; provided, that in the case of a
Remarketing following a Change in Control, the Company shall make such request
eight Business Days prior to the Remarketing Date.

         (b) Under Section 5.4 of the Purchase Contract Agreement, holders of
Corporate Units that do not give notice of their intention to make a Cash
Settlement of the Purchase Contract component of their Corporate Units prior to
such time in the manner specified in such Section, or that give such notice but
fail to deliver cash prior to 11:00 a.m., New York City time, on or prior to the
fifth Business Day preceding the Purchase Contract Settlement Date, shall be
deemed to have consented to the disposition of the Debenture component of their
Corporate Units in the Remarketing. Promptly after 11:00 a.m., New York City
time, on such fifth Business Day, the Purchase Contract Agent, based on notices
from the Purchase Contract Agent as to Purchase Contracts for which Cash
Settlement has been elected and cash received, shall notify the Company and the
Remarketing Agent of the amount of Debentures to be tendered for purchase in the
Remarketing.

         (c) If any Holder of Debentures does not give a notice of its intention
to make a Cash Settlement or gives such notice but fails to deliver cash as
described in the foregoing subsection (b), then the Debentures of such Holder
shall be deemed tendered for purchase in the Remarketing, notwithstanding any
failure by such Holder to deliver or properly deliver such Debentures to the
Remarketing Agent for purchase.


                                       9
<PAGE>   10


         (d) The right of each Holder to have Debentures tendered for purchase
will be limited to the extent that (i) the Remarketing Agent conducts a
Remarketing pursuant to the terms of the Remarketing Agreement, (ii) the
Remarketing Agent is able to find a purchaser or purchasers for the tendered
Debentures, and (iii) such purchaser or purchasers deliver the purchase price
therefor to the Remarketing Agent.

         (e) On the Remarketing Date, the Remarketing Agent will use
commercially reasonable efforts to remarket, at a price equal to 100.50% of
their aggregate principal amount, the Debentures tendered or deemed tendered for
purchase.

         (f) If, as a result of the efforts described in the foregoing
subsection (e), the Remarketing Agent determines that it will be able to
remarket all of the Debentures tendered or deemed tendered for purchase at a
price of 100.50% of their aggregate principal amount prior to 4:00 p.m., New
York City time, on the Remarketing Date, the Remarketing Agent shall determine
the "INTEREST RATE", which shall be the rate per annum (rounded to the nearest
one-thousandth (0.001) of one percent per annum) that the Remarketing Agent
determines, in its sole judgment, to be the lowest rate per annum that will
enable it to remarket at that price all of the Debentures tendered or deemed
tendered for Remarketing.

         (g) If none of the Holders of the Corporate Units elects to have
Debentures remarketed in the Remarketing, the Interest Rate shall be the rate
determined by the Remarketing Agent, in its sole discretion, as the rate that
would have been established had a Remarketing been held on the Remarketing Date.

         (h) If, by 4:00 p.m., New York City time, on the Remarketing Date, the
Remarketing Agent is unable to remarket all of the Debentures tendered or deemed
tendered for purchase, a "Failed Remarketing" shall be deemed to have occurred,
and the Remarketing Agent shall so advise by telephone the Depositary, the
Trustee and the Company. In the event of a Failed Remarketing, the Interest Rate
shall equal (i) the Two-Year Benchmark Treasury Rate plus (ii) the Applicable
Margin.

         (i) By approximately 4:30 p.m., New York City time, on the Remarketing
Date, provided that there has not been a Failed Remarketing, the Remarketing
Agent shall advise, by telephone (i) the Depositary, the Trustee and the Company
of the Interest Rate determined in the Remarketing and the amount of Debentures
sold in the Remarketing, (ii) each purchaser (or the Depositary participant of a
purchaser) of the Interest Rate and the amount of Debentures such purchaser is
to purchase, and (iii) each purchaser to give instructions to its Depositary
participant to pay the purchase price on the Purchase Contract Settlement Date
in same day funds against delivery of the Debentures purchased through the
facilities of the Depositary.

         (j) In accordance with the Depositary's normal procedures, on the
Purchase Contract Settlement Date, the transactions described above with respect
to each Debenture deemed tendered for purchase and sold in the Remarketing shall
be executed through the Depositary, and the accounts of the respective
Depositary participants shall be debited and credited and such Debentures
delivered by book-entry as necessary to effect purchases and sales of such
Debentures. The Depositary shall make payment in accordance with its normal
procedures.

         (k) The Remarketing Agent is not obligated to purchase any Debentures
that otherwise would remain unsold in the Remarketing. Neither the Company nor
the Remarketing Agent shall be obligated in any case to provide funds to make
payment upon tender of the Debentures for Remarketing.

         (l) As provided in Section 4 of the Remarketing Agreement, the Company,
in its capacity as issuer of the Debentures, shall be liable for, and shall pay,
any and all fees, costs and expenses incurred in connection with the
Remarketing.


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         (m) The tender and settlement procedures set in this Section 7.1,
including provisions for payment by purchasers of the Debentures in the
Remarketing, shall be subject to modification to the extent required by the
Depositary or if the book-entry system is no longer available for the Debentures
at the time of the Remarketing, to facilitate the tendering and remarketing of
the Debentures in certificated form. In addition, the Remarketing Agent may
modify the settlement procedures set forth in this Article in order to
facilitate the settlement process.


                                  ARTICLE VIII
                                  MISCELLANEOUS

         SECTION 8.1. RATIFICATION OF INDENTURE. The Indenture, as supplemented
by this First Supplemental Indenture, is in all respects ratified and confirmed.
This First Supplemental Indenture shall be deemed part of the Indenture in the
manner and to the extent provided in this First Supplemental Indenture and the
Indenture.

         SECTION 8.2. TRUSTEE NOT RESPONSIBLE FOR RECITALS. The recitals
contained in this First Supplemental Indenture are made by the Company and not
by the Trustee, and the Trustee assumes no responsibility for the correctness of
such recitals. The Trustee makes no representation as to the validity or
sufficiency of this First Supplemental Indenture.

         SECTION 8.3. GOVERNING LAW. This First Supplemental Indenture and each
Debenture shall be deemed to be a contract made under the internal laws of the
State of New York and for all purposes shall be construed in accordance with the
laws of that State.

         SECTION 8.4. SEVERABILITY. In case any one or more of the provisions
contained in this First Supplemental Indenture or in the Debentures shall for
any reason be held to be invalid, illegal or unenforceable in any respect, such
invalidity, illegality or unenforceability shall not affect any other provisions
of this First Supplemental Indenture or of the Debentures, but this First
Supplemental Indenture and the Debentures shall be construed as if such invalid
or illegal or unenforceable provision had never been contained in this First
Supplemental Indenture or the Debentures.

         SECTION 8.5. COUNTERPARTS. This First Supplemental Indenture 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.



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         IN WITNESS WHEREOF, the parties have caused this First Supplemental
Indenture to be duly executed, and their respective corporate seals to be
affixed and attested on this First Supplemental Indenture, on the date or dates
indicated in the acknowledgments and as of the day and year first above written.

                                       NEW NISOURCE INC.



                                       By:
                                         --------------------------------------
                                                Name:
                                                Title:
Attest:


Name:
Title:


                                       THE CHASE MANHATTAN BANK, as Trustee


                                       By:
                                         --------------------------------------
                                                Name:
                                                Title:
Attest:


Name:
Title:











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