<PAGE>   1
                                                                     EXHIBIT 4.1

                                                                  EXECUTION COPY


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                            PAGEMART WIRELESS, INC.,
                                            as Issuer


                                       and


                    UNITED STATES TRUST COMPANY OF NEW YORK,
                                            as Trustee




                              ---------------------


                                    Indenture

                          Dated as of January 28, 1998


                              ---------------------


               11 1/4% Senior Subordinated Discount Notes due 2008


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<PAGE>   2



                              CROSS-REFERENCE TABLE


<TABLE>
<CAPTION>
TIA Sections                                                                    Indenture Sections
------------                                                                    ------------------

<S>                                                                             <C>
Section 310(a)(1) ..............................................................    7.10
(a)(2) .........................................................................    7.10
(b) ............................................................................    7.08
Section 313(c) .................................................................    7.06; 11.02
Section 314(a) .................................................................    4.17; 11.02
(a)(4) .........................................................................    4.16; 11.02
(c)(1) .........................................................................    11.03
(c)(2) .........................................................................    11.03
(e) ............................................................................    11.04
Section 315(b) .................................................................    7.05; 11.02
Section 316(a)(1)(A) ...........................................................    6.05
(a)(1)(B) ......................................................................    6.04
(b) ............................................................................    6.07
Section 317(a)(1) ..............................................................    6.08
(a)(2) .........................................................................    6.09
Section 318(a) .................................................................    11.01
(c) ............................................................................    11.01
</TABLE>














Note:    The Cross-Reference Table shall not for any purpose be deemed to be a
         part of the Indenture.

<PAGE>   3
                  INDENTURE, dated as of January 28, 1998, between PAGEMART
WIRELESS, INC., a Delaware corporation, as Issuer (the "Company"), and UNITED
STATES TRUST COMPANY OF NEW YORK, a New York corporation, as Trustee (the
"Trustee").

                             RECITALS OF THE COMPANY

                  The Company has duly authorized the execution and delivery of
this Indenture to provide for the issuance of up to $432,000,000 aggregate
principal amount at maturity ($249,700,320 initial Accreted Value) of the
Company's 11 1/4% Senior Subordinated Discount Notes due 2008 (the "Notes")
issuable as provided in this Indenture. All things necessary to make this
Indenture a valid agreement of the Company, in accordance with its terms, have
been done, and the Company has done all things necessary to make the Notes, when
executed by the Company and authenticated and delivered by the Trustee hereunder
and duly issued by the Company, the valid obligations of the Company as
hereinafter provided.

                  This Indenture is subject to, and shall be governed by, the
provisions of the Trust Indenture Act of 1939, as amended, that are required to
be a part of and to govern indentures qualified under the Trust Indenture Act of
1939, as amended.

                      AND THIS INDENTURE FURTHER WITNESSETH

                  For and in consideration of the premises and the purchase of
the Notes by the Holders thereof, it is mutually covenanted and agreed, for the
equal and proportionate benefit of all Holders, as follows.


                                   ARTICLE ONE
                   DEFINITIONS AND INCORPORATION BY REFERENCE

SECTION 1.01.  Definitions.

                  "12 1/4% Indenture" means the Indenture dated as of October
19, 1993, between PageMart, Inc., a Delaware corporation, and United States
Trust Company of New York, a New York corporation, as Trustee relating to the 12
1/4% Notes, as amended from time to time.

                  "15% Indenture" means the Indenture dated as of January 17,
1995, between the Company (f/k/a PageMart Nationwide Inc.) and United States
Trust Company of New York, a New York corporation, as Trustee relating to the
15% Notes, as amended from time to time.

<PAGE>   4


                                        2

                  "12 1/4% Notes" means the 12 1/4% Senior Discount Notes of
PageMart, Inc. due 2003 issued pursuant to the 12 1/4% Indenture.

                  "15% Notes" means the 15% Senior Discount Notes of the Company
due 2005 issued pursuant to the 15% Indenture.

                  "Acceleration Notice" has the meaning provided in Section
6.02.

                  "Accreted Value" means, for any Specified Date, the amount
calculated pursuant to (i), (ii), (iii) or (iv) for each $1,000 principal amount
at maturity of Notes:

                  (i) if the Specified Date occurs on one of the following dates
         (each a "Semi-Annual Accrual Date"), the Accreted Value will equal the
         amount set forth below for such Semi-Annual Accrual Date:

<TABLE>
<CAPTION>
    SEMI-ANNUAL                               Accreted
   Accrual Date                                Value
------------------                            --------
<S>                                           <C>
August 1, 1998                                $611.08
February 1, 1999                              $645.45
August 1, 1999                                $681.76
February 1, 2000                              $720.11
August 1, 2000                                $760.62
February 1, 2001                              $803.40
August 1, 2001                                $848.59
February 1, 2002                              $896.32
August 1, 2002                                $946.74
February 1, 2003                              $1,000.00
</TABLE>



                  (ii) if the Specified Date occurs before the first Semi-Annual
         Accrual Date, the Accreted Value will equal the sum of (a) $578.01 and
         (b) an amount equal to the product of (1) the Accreted Value for the
         first Semi-Annual Accrual Date less $578.01 multiplied by (2) a
         fraction, the numerator of which is the number of days from the issue
         date of the Notes to the Specified Date, using a 360-day year of twelve
         30-day months, and the denominator of which is the number of days
         elapsed from the issue date of the Notes to the first Semi-Annual
         Accrual Date, using a 360-day year of twelve 30-day months;

                  (iii) if the Specified Date occurs between two Semi-Annual
         Accrual Dates, the Accreted Value will equal the sum of (a) the
         Accreted Value for the Semi-Annual Accrual Date immediately preceding
         such Specified Date and (b) an amount equal to the product of (1) the
         Accreted Value for the immediately following Semi-Annual

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                                        3

         Accrual Date less the Accreted Value for the immediately preceding
         Semi-Annual Accrual Date multiplied by (2) a fraction, the numerator of
         which is the number of days from the immediately preceding Semi-Annual
         Accrual Date to the Specified Date, using a 360-day year of twelve
         30-day months, and the denominator of which is 180; or

                  (iv) if the Specified Date occurs after the last Semi-Annual
         Accrual Date, the Accreted Value will equal $1,000.

                  "Acquired Indebtedness" means Indebtedness of a Person
existing at the time such Person became a Restricted Subsidiary and not Incurred
in connection with, or in contemplation of, such Person becoming a Restricted
Subsidiary.

                  "Adjusted Consolidated Net Income" means, for any period, the
aggregate net income (or loss) of the Company and its Restricted Subsidiaries
for such period determined in conformity with GAAP; provided that the following
items shall be excluded in computing Adjusted Consolidated Net Income (without
duplication): (i) the net income (or loss) of any Person that is not a
Restricted Subsidiary, except (x) with respect to net income, to the extent of
the amount of dividends or other distributions actually paid to the Company or
any of its Restricted Subsidiaries by such Person during such period and (y)
with respect to net losses, to the extent of the amount of Investments made by
the Company or any Restricted Subsidiary in such Person during such period, (ii)
solely for the purposes of calculating the amount of Restricted Payments that
may be made pursuant to clause (C) of the first paragraph of Section 4.06 (and
in such case, except to the extent includible pursuant to clause (i) above), the
net income (or loss) of any Person accrued prior to the date it becomes a
Restricted Subsidiary or is merged into or consolidated with the Company or any
of its Restricted Subsidiaries or all or substantially all of the property and
assets of such Person are acquired by the Company or any of its Restricted
Subsidiaries, (iii) the net income of any Restricted Subsidiary to the extent
that the declaration or payment of dividends or similar distributions by such
Restricted Subsidiary of such net income is not at the time permitted by the
operation of the terms of its charter or any agreement, instrument, judgment,
decree, order, statute, rule or governmental regulation applicable to such
Restricted Subsidiary; (iv) any gains or losses (on an after-tax basis)
attributable to Asset Sales; (v) except for purposes of calculating the amount
of Restricted Payments that may be made pursuant to clause (C) of the first
paragraph of Section 4.06, any amount paid as dividends on Preferred Stock of
the Company or any Restricted Subsidiary owned by Persons other than the Company
and any of its Restricted Subsidiaries; and (vi) all extraordinary gains and
extraordinary losses.

                  "Adjusted Consolidated Net Tangible Assets" means the total
amount of assets of the Company and its Restricted Subsidiaries (less applicable
depreciation, amortization and other valuation reserves), except to the extent
resulting from write-ups of capital assets

<PAGE>   6


                                        4

(excluding write-ups in connection with accounting for acquisitions in
conformity with GAAP), after deducting therefrom (i) all current liabilities of
the Company and its Restricted Subsidiaries (excluding intercompany items) and
(ii) all goodwill, trade names, trademarks, patents, unamortized debt discount
and expense and other like intangibles, all as set forth on the most recently
available quarterly or annual consolidated balance sheet of the Company and its
Restricted Subsidiaries, prepared in conformity with GAAP, and filed with the
Commission or provided to the Trustee pursuant to Section 4.18.

                  "Affiliate" means, as applied to any Person, any other Person
directly or indirectly controlling, controlled by, or under direct or indirect
common control with, such Person. For purposes of this definition, "control"
(including, with correlative meanings, the terms "controlling," "controlled by"
and "under common control with"), as applied to any Person, means the
possession, directly or indirectly, of the power to direct or cause the
direction of the management and policies of such Person, whether through the
ownership of voting securities, by contract or otherwise.

                  "Agent" means any Registrar, Paying Agent, authenticating
agent or co-Registrar.

                  "Agent Members" has the meaning provided in Section 2.07(a).

                  "Asset Acquisition" means (i) an investment by the Company or
any of its Restricted Subsidiaries in any other Person pursuant to which such
Person shall become a Restricted Subsidiary or shall be merged into or
consolidated with the Company or any of its Restricted Subsidiaries or (ii) an
acquisition by the Company or any of its Restricted Subsidiaries of the property
and assets of any Person other than the Company or any of its Restricted
Subsidiaries that constitute substantially all of a division or line of business
of such Person.

                  "Asset Disposition" means the sale or other disposition by the
Company or any of its Restricted Subsidiaries (other than to the Company or
another Restricted Subsidiary) of (i) all or substantially all of the Capital
Stock of any Restricted Subsidiary or (ii) all or substantially all of the
assets that constitute a division or line of business of the Company or any of
its Restricted Subsidiaries.

                  "Asset Sale" means any sale, transfer or other disposition
(including by way of merger, consolidation or sale-leaseback transactions) in
one transaction or a series of related transactions by the Company or any of its
Restricted Subsidiaries to any Person other than the Company or any of its
Restricted Subsidiaries of (i) all or any of the Capital Stock of any Restricted
Subsidiary, (ii) all or substantially all of the property and assets of an
operating unit or business of the Company or any of its Restricted Subsidiaries
or (iii) any other property and assets (other than the Capital Stock or other
Investment in an Unrestricted

<PAGE>   7


                                        5

Subsidiary) of the Company or any of its Restricted Subsidiaries outside the
ordinary course of business of the Company or such Restricted Subsidiary and, in
each case, that is not governed by the provisions of Article Five; provided that
"Asset Sale" shall not include (a) sales or other dispositions of inventory,
receivables and other current assets, (b) sales, transfers or other dispositions
of assets constituting Restricted Payments permitted to be made under Section
4.06 or (c) sales or other dispositions of assets for consideration at least
equal to the fair market value of the assets sold or disposed of, to the extent
that the consideration received would constitute property or assets of the kinds
described in clause (B) of Section 4.11.

                  "Average Life" means, at any date of determination with
respect to any debt security, the quotient obtained by dividing (i) the sum of
the products of (a) the number of years from such date of determination to the
dates of each successive scheduled principal payment of such debt security and
(b) the amount of such principal payment by (ii) the sum of all such principal
payments.

                  "Bank Agent" shall mean BT Commercial Corporation, or its
successor as agent for the lenders under the Credit Agreement.

                  "Board of Directors" means the Board of Directors of the
Company or any committee of such Board of Directors duly authorized to act under
this Indenture.

                  "Board Resolution" means a copy of a resolution, certified by
the Secretary of the Company to have been duly adopted by the Board of Directors
and to be in full force and effect on the date of such certification, and
delivered to the Trustee.

                  "Business Day" means any day except a Saturday, Sunday or
other day on which commercial banks in The City of New York, or in the city of
the Corporate Trust Office of the Trustee, are authorized by law to close.

                  "Capital Stock" means, with respect to any Person, any and all
shares, interests, participations or other equivalents (however designated,
whether voting or non-voting) in equity of such Person, whether outstanding on
the Closing Date or issued thereafter, including, without limitation, all Common
Stock and Preferred Stock.

                  "Capitalized Lease" means, as applied to any Person, any lease
of any property (whether real, personal or mixed) of which the discounted
present value of the rental obligations of such Person as lessee, in conformity
with GAAP, is required to be capitalized on the balance sheet of such Person.

                  "Capitalized Lease Obligations" means the discounted present
value of the rental obligations under a Capitalized Lease.

<PAGE>   8


                                        6


                  "Change of Control" means such time as (i) a "person" or
"group" (within the meaning of Sections 13(d) and 14(d)(2) of the Exchange Act)
becomes the ultimate "beneficial owner" (as defined in Rule 13d-3 under the
Exchange Act) of more than 30% of the total voting power of the Voting Stock and
such ownership is greater than the amount of the total voting power of the
Voting Stock of the Company, on a fully diluted basis, than is held by the
Existing Stockholders on such date; or (ii) individuals who on the Closing Date
constitute the Board of Directors (together with any new directors whose
election by the Board of Directors or whose nomination by the Board of Directors
for election by the Company's stockholders was approved by a vote of at least
two-thirds of the members of the Board of Directors then in office who either
were members of the Board of Directors on the Closing Date or whose election or
nomination for election was previously so approved) cease for any reason to
constitute a majority of the members of the Board of Directors then in office.

                  "Closing Date" means the date on which the Notes are
originally issued under this Indenture.

                  "Commission" means the Securities and Exchange Commission, as
from time to time constituted, created under the Exchange Act or, if at any time
after the execution of this instrument such Commission is not existing and
performing the duties now assigned to it under the TIA, then the body performing
such duties at such time.

                  "Common Stock" means, with respect to any Person, any and all
shares, interests, participations or other equivalents (however designated,
whether voting or non-voting) of such Person's common stock, whether now
outstanding or issued after the date of this Indenture, including, without
limitation, all series and classes of such common stock.

                  "Company" means the party named as such in the first paragraph
of this Indenture until a successor replaces it pursuant to Article Five of this
Indenture and thereafter means the successor.

                  "Company Order" means a written request or order signed in the
name of the Company (i) by its Chairman, a Vice Chairman, its President or a
Vice President and (ii) by its Treasurer, an Assistant Treasurer, its Secretary
or an Assistant Secretary and delivered to the Trustee; provided, however, that
such written request or order may be signed by any two of the officers or
directors listed in clause (i) above in lieu of being signed by one of such
officers or directors listed in such clause (i) and one of the officers listed
in clause (ii) above.

                  "Consolidated EBITDA" means, for any period, Adjusted
Consolidated Net Income for such period plus, to the extent such amount was
deducted in calculating such Adjusted Consolidated Net Income, (i) Consolidated
Interest Expense, (ii) income taxes

<PAGE>   9


                                        7

(other than income taxes (either positive or negative) attributable to
extraordinary and non-recurring gains or losses or sales of assets), (iii)
depreciation expense, (iv) amortization expense and (v) all other non-cash items
reducing Adjusted Consolidated Net Income (other than items that will require
cash payments and for which an accrual or reserve is, or is required by GAAP to
be, made), less all non-cash items increasing Adjusted Consolidated Net Income,
all as determined on a consolidated basis for the Company and its Restricted
Subsidiaries in conformity with GAAP; provided that, if any Restricted
Subsidiary is not a Wholly Owned Restricted Subsidiary, Consolidated EBITDA
shall be reduced (to the extent not otherwise reduced in accordance with GAAP)
by an amount equal to (A) the amount of the Adjusted Consolidated Net Income
attributable to such Restricted Subsidiary multiplied by (B) the percentage
ownership interest in the income of such Restricted Subsidiary not owned on the
last day of such period by the Company or any of its Restricted Subsidiaries.

                  "Consolidated Interest Expense" means, for any period, the
aggregate amount of interest in respect of Indebtedness (including, without
limitation, amortization of original issue discount on any Indebtedness and the
interest portion of any deferred payment obligation, calculated in accordance
with the effective interest method of accounting; all commissions, discounts and
other fees and charges owed with respect to letters of credit and bankers'
acceptance financing; the net costs associated with Interest Rate Agreements;
and Indebtedness that is Guaranteed or secured by the Company or any of its
Restricted Subsidiaries) and all but the principal component of rentals in
respect of Capitalized Lease Obligations paid, accrued or scheduled to be paid
or to be accrued by the Company and its Restricted Subsidiaries during such
period; excluding, however, (i) any amount of such interest of any Restricted
Subsidiary if the net income of such Restricted Subsidiary is excluded in the
calculation of Adjusted Consolidated Net Income pursuant to clause (iii) of the
definition thereof (but only in the same proportion as the net income of such
Restricted Subsidiary is excluded from the calculation of Adjusted Consolidated
Net Income pursuant to clause (iii) of the definition thereof) and (ii) any
premiums, fees and expenses (and any amortization thereof) payable in connection
with the offering of the Notes, all as determined on a consolidated basis
(without taking into account Unrestricted Subsidiaries) in conformity with GAAP.

                  "Consolidated Leverage Ratio" means, on any Transaction Date,
the ratio of (i) the aggregate amount of Indebtedness of the Company and its
Restricted Subsidiaries on a consolidated basis outstanding on such Transaction
Date to (ii) the aggregate amount of Consolidated EBITDA for the then most
recent four fiscal quarters for which financial statements of the Company have
been filed with the Commission or provided to the Trustee pursuant to Section
4.18 (such four fiscal quarter period being the "Four Quarter Period"); provided
that, in making the foregoing calculation, (A) pro forma effect shall be given
to any Indebtedness to be Incurred or repaid on the Transaction Date; (B) pro
forma effect shall be given to Asset Dispositions and Asset Acquisitions
(including giving pro forma effect to the application of proceeds of any Asset
Disposition) that occur from the beginning of the Four

<PAGE>   10


                                        8

Quarter Period through and including the Transaction Date (the "Reference
Period"), as if they had occurred and such proceeds had been applied on the
first day of such Reference Period; and (C) pro forma effect shall be given to
asset dispositions and asset acquisitions (including giving pro forma effect to
the application of proceeds of any asset disposition) that have been made by any
Person that has become a Restricted Subsidiary or has been merged with or into
the Company or any Restricted Subsidiary during such Reference Period and that
would have constituted Asset Dispositions or Asset Acquisitions had such
transactions occurred when such Person was a Restricted Subsidiary as if such
asset dispositions or asset acquisitions were Asset Dispositions or Asset
Acquisitions that occurred on the first day of such Reference Period; provided
that to the extent that clause (B) or (C) of this sentence requires that pro
forma effect be given to an Asset Acquisition or Asset Disposition, such pro
forma calculation shall be based upon the four full fiscal quarters immediately
preceding the Transaction Date of the Person, or division or line of business of
the Person, that is acquired or disposed of for which financial information is
available.

                  "Consolidated Net Worth" means, at any date of determination,
stockholders' equity as set forth on the most recently available quarterly or
annual consolidated balance sheet of the Company and its Restricted Subsidiaries
(which shall be as of a date not more than 90 days prior to the date of such
computation, and which shall not take into account Unrestricted Subsidiaries),
less any amounts attributable to Redeemable Stock or any equity security
convertible into or exchangeable for Indebtedness, the cost of treasury stock
and the principal amount of any promissory notes receivable from the sale of the
Capital Stock of the Company or any of its Restricted Subsidiaries, each item to
be determined in conformity with GAAP (excluding the effects of foreign currency
exchange adjustments under Financial Accounting Standards Board Statement of
Financial Accounting Standards No. 52).

                  "Corporate Trust Office" means the office of the Trustee at
which the corporate trust business of the Trustee shall, at any particular time,
be principally administered, which office is, at the date of this Indenture,
located at 114 W. 47th Street, New York, New York 10036, Attention: Corporate
Trust Department.

                  "Credit Agreement" means the Credit Agreement dated as of May
11, 1995, as amended, by and among the Company (f/k/a PageMart Nationwide Inc.),
the lenders named therein, BT Commercial Corporation, as Agent and Bankers Trust
Company, as Issuing Bank, together with the related documents thereof (including
without limitation any guarantees and security documents), in each case as such
agreements may be amended (including any amendment and restatement thereof),
supplemented, renewed, extended, substituted, replaced or otherwise modified
from time to time, including any agreement extending the maturity of,
refinancing or otherwise restructuring (including, but not limited to, the
inclusion of additional borrowers thereunder that are Subsidiaries of the
Company) all or any portion of the Indebtedness under such agreement or any
successor agreement, with

<PAGE>   11


                                        9

the same or different lenders as such agreement may be amended, renewed,
extended, substituted, replaced, restated and otherwise modified from time to
time.

                  "Currency Agreement" means any foreign exchange contract,
currency swap agreement or other similar agreement or arrangement.

                  "Default" means any event that is, or after notice or passage
of time or both would be, an Event of Default.

                  "Depositary" shall mean The Depository Trust Company, its
nominees, and their respective successors.

                  "Designated Senior Indebtedness" means the Indebtedness under
the Credit Agreement and the 15% Notes and any other Indebtedness constituting
Senior Indebtedness that, at the date of determination, has an aggregate
principal amount outstanding of at least $25 million and that is specifically
designated by the Company, in the instrument creating or evidencing such Senior
Indebtedness as "Designated Senior Indebtedness".

                  "Event of Default" has the meaning provided in Section 6.01.

                  "Excess Proceeds" has the meaning provided in Section 4.11.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

                  "Exchange Notes" means any notes of the Company containing
terms identical to the Notes (except that such Exchange Notes (i) shall be
registered under the Securities Act and (ii) shall have an interest rate equal
to 11 1/4% per annum, without provision for adjustment as provided in the fourth
paragraph of Section 1 of the Notes) that are issued and exchanged for the Notes
pursuant to the Registration Rights Agreement and this Indenture.

                  "Existing Stockholders" means (i) The Morgan Stanley Leveraged
Equity Fund II, L.P., Morgan Stanley Capital Partners III, L.P., Morgan Stanley
Capital Investors, L.P., Morgan Stanley Venture Capital Fund, L.P., Morgan
Stanley Venture Capital Fund II, L.P., Morgan Stanley Venture Capital Fund II,
C.V., Morgan Stanley Venture Investors, L.P., Accel Telecom L.P., Accel III L.P.
and Accel Investors '89 L.P and (ii) solely for purposes of determining whether
any other person's ownership of Voting Stock exceeds the voting power of the
Voting Stock held by the Existing Stockholders, First Plaza Group Trust, Pulsar
Internacional, S.A. de C.V., John D. Beletic and Roger D. Linquist.

                  "fair market value" means the price that would be paid in an
arm's-length transaction between an informed and willing seller under no
compulsion to sell and an informed and willing buyer under no compulsion to buy,
as determined in good faith by the

<PAGE>   12


                                       10

Board of Directors, whose determination shall be conclusive if evidenced by a
Board Resolution; provided that for purposes of clause (xi) of the second
paragraph of Section 4.03(a), (x) the fair market value of any security
registered under the Exchange Act shall be the average of the closing prices,
regular way, of such security for the 20 consecutive trading days immediately
preceding the sale of Capital Stock and (y) in the event the aggregate fair
market value of any other property (other than cash or cash equivalents)
received by the Company exceeds $10 million, the fair market value of such
property shall be determined by a nationally recognized investment banking firm
and set forth in their written opinion which shall be delivered to the Trustee.

                  "GAAP" means generally accepted accounting principles in the
United States of America as in effect as of the Closing Date, including, without
limitation, those set forth in the opinions and pronouncements of the Accounting
Principles Board of the American Institute of Certified Public Accountants and
statements and pronouncements of the Financial Accounting Standards Board or in
such other statements by such other entity as approved by a significant segment
of the accounting profession. All ratios and computations based on GAAP
contained or referred to in this Indenture shall be computed in conformity with
GAAP applied on a consistent basis, except that calculations made for purposes
of determining compliance with the terms of the covenants set forth in Article
Four and Article Five and with other provisions of this Indenture shall be made
without giving effect to (i) the amortization of any expenses incurred in
connection with the offering of the Notes and (ii) except as otherwise provided,
the amortization of any amounts required or permitted by Accounting Principles
Board Opinion Nos. 16 and 17.

                  "Global Notes" has the meaning provided in Section 2.01.

                  "Guarantee" means any obligation, contingent or otherwise, of
any Person directly or indirectly guaranteeing any Indebtedness of any other
Person and, without limiting the generality of the foregoing, any obligation,
direct or indirect, contingent or otherwise, of such Person (i) to purchase or
pay (or advance or supply funds for the purchase or payment of) such
Indebtedness of such other Person (whether arising by virtue of partnership
arrangements, or by agreements to keep-well, to purchase assets, goods,
securities or services (unless such purchase arrangements are on arm's-length
terms and are entered into in the ordinary course of business), to take-or-pay,
or to maintain financial statement conditions or otherwise) or (ii) entered into
for purposes of assuring in any other manner the obligee of such Indebtedness of
the payment thereof or to protect such obligee against loss in respect thereof
(in whole or in part); provided that the term "Guarantee" shall not include
endorsements for collection or deposit in the ordinary course of business.
The term "Guarantee" used as a verb has a corresponding meaning.

                  "Guaranteed Indebtedness" has the meaning provided in Section
4.09.

<PAGE>   13


                                       11

                  "Holder" means the registered holder of any Note.

                  "Incur" means, with respect to any Indebtedness, to incur,
create, issue, assume, Guarantee or otherwise become liable for or with respect
to, or become responsible for, the payment of, contingently or otherwise, such
Indebtedness, including an "Incurrence" of Acquired Indebtedness; provided that
neither the accrual of interest nor the accretion of original issue discount
shall be considered an Incurrence of Indebtedness.

                  "Indebtedness" means, with respect to any Person at any date
of determination (without duplication), (i) all indebtedness of such Person for
borrowed money, (ii) all obligations of such Person evidenced by bonds,
debentures, notes or other similar instruments, (iii) all obligations of such
Person in respect of letters of credit or other similar instruments (including
reimbursement obligations with respect thereto), (iv) all obligations of such
Person to pay the deferred and unpaid purchase price of property or services,
which purchase price is due more than six months after the date of placing such
property in service or taking delivery and title thereto or the completion of
such services, except Trade Payables, (v) all Capitalized Lease Obligations of
such Person, (vi) all Indebtedness of other Persons secured by a Lien on any
asset of such Person, whether or not such Indebtedness is assumed by such
Person; provided that the amount of such Indebtedness shall be the lesser of (A)
the fair market value of such asset at such date of determination and (B) the
amount of such Indebtedness, (vii) all Indebtedness of other Persons Guaranteed
by such Person to the extent such Indebtedness is Guaranteed by such Person and
(viii) to the extent not otherwise included in this definition, obligations
under Currency Agreements and Interest Rate Agreements. The amount of
Indebtedness of any Person at any date shall be the outstanding balance at such
date of all unconditional obligations as described above and, with respect to
contingent obligations, the maximum liability upon the occurrence of the
contingency giving rise to the obligation, provided (A) that the amount
outstanding at any time of any Indebtedness issued with original issue discount
is the face amount of such Indebtedness less the remaining unamortized portion
of the original issue discount of such Indebtedness at such time as determined
in conformity with GAAP, (B) that money borrowed and set aside at the time of
the Incurrence of any Indebtedness in order to prefund the payment of the
interest on such Indebtedness shall not be deemed to be "Indebtedness" so long
as such money is held to secure the payment of such interest and (C) that
Indebtedness shall not include any liability for federal, state, local or other
taxes.

                  "Indenture" means this Indenture as originally executed or as
it may be amended or supplemented from time to time by one or more indentures
supplemental to this Indenture entered into pursuant to the applicable
provisions of this Indenture.

                  "Institutional Accredited Investor" means an institution that
is an "accredited investor" as that term is defined in Rule 501(a)(1), (2), (3)
or (7) under the Securities Act.

<PAGE>   14


                                       12

                  "Interest Payment Date" means each semiannual interest payment
date on February 1 and August 1 of each year, commencing August 1, 2003.

                  "Interest Rate Agreement" means any interest rate protection
agreement, interest rate future agreement, interest rate option agreement,
interest rate swap agreement, interest rate cap agreement, interest rate collar
agreement, interest rate hedge agreement, option or future contract or other
similar agreement or arrangement.

                  "Investment" in any Person means any direct or indirect
advance, loan or other extension of credit (including, without limitation, by
way of Guarantee or similar arrangement; but excluding advances to customers in
the ordinary course of business that are, in conformity with GAAP, recorded as
accounts receivable on the balance sheet of the Company or its Restricted
Subsidiaries) or capital contribution to (by means of any transfer of cash or
other property to others or any payment for property or services for the account
or use of others), or any purchase or acquisition of Capital Stock, bonds,
notes, debentures or other similar instruments issued by, such Person and shall
include (i) the designation of a Restricted Subsidiary as an Unrestricted
Subsidiary and (ii) the fair market value of the Capital Stock (or any other
Investment), held by the Company or any of its Restricted Subsidiaries, of (or
in) any Person that has ceased to be a Restricted Subsidiary, including, without
limitation, by reason of any transaction permitted by clause (iii) of Section
4.08; provided that the fair market value of the Investment remaining in any
Person that has ceased to be a Restricted Subsidiary shall not exceed the
aggregate amount of Investments previously made in such Person valued at the
time such Investments were made less the net reduction of such Investments. For
purposes of the definition of "Unrestricted Subsidiary" and Section 4.06, (i)
"Investment" shall include the fair market value of the assets (net of
liabilities (other than liabilities to the Company or any of its Restricted
Subsidiaries)) of any Restricted Subsidiary at the time that such Restricted
Subsidiary is designated an Unrestricted Subsidiary, (ii) the fair market value
of the assets (net of liabilities (other than liabilities to the Company or any
of its Restricted Subsidiaries)) of any Unrestricted Subsidiary at the time that
such Unrestricted Subsidiary is designated a Restricted Subsidiary shall be
considered a reduction in outstanding Investments and (iii) any property
transferred to or from an Unrestricted Subsidiary shall be valued at its fair
market value at the time of such transfer.

                  "Lien" means any mortgage, pledge, security interest,
encumbrance, lien or charge of any kind (including, without limitation, any
conditional sale or other title retention agreement or lease in the nature
thereof or any agreement to give any security interest).

                  "Moody's" means Moody's Investors Service, Inc. and its
successors.

                  "Net Cash Proceeds" means, (a) with respect to any Asset Sale,
the proceeds of such Asset Sale in the form of cash or cash equivalents,
including payments in respect of deferred payment obligations (to the extent
corresponding to the principal, but not interest,

<PAGE>   15


                                       13

component thereof) when received in the form of cash or cash equivalents (except
to the extent such obligations are financed or sold with recourse to the Company
or any Restricted Subsidiary) and proceeds from the conversion of other property
received when converted to cash or cash equivalents, net of (i) brokerage
commissions and other fees and expenses (including fees and expenses of counsel
and investment bankers) related to such Asset Sale, (ii) provisions for all
taxes (whether or not such taxes will actually be paid or are payable) as a
result of such Asset Sale without regard to the consolidated results of
operations of the Company and its Restricted Subsidiaries, taken as a whole,
(iii) payments made to repay Indebtedness or any other obligation outstanding at
the time of such Asset Sale that either (A) is secured by a Lien on the property
or assets sold or (B) is required to be paid as a result of such sale and (iv)
appropriate amounts to be provided by the Company or any Restricted Subsidiary
as a reserve against any liabilities associated with such Asset Sale, including,
without limitation, pension and other post-employment benefit liabilities,
liabilities related to environmental matters and liabilities under any
indemnification obligations associated with such Asset Sale, all as determined
in conformity with GAAP and (b) with respect to any issuance or sale of Capital
Stock, the proceeds of such issuance or sale in the form of cash or cash
equivalents, including payments in respect of deferred payment obligations (to
the extent corresponding to the principal, but not interest, component thereof)
when received in the form of cash or cash equivalents (except to the extent such
obligations are financed or sold with recourse to the Company or any Restricted
Subsidiary) and proceeds from the conversion of other property received when
converted to cash or cash equivalents, net of attorney's fees, accountants'
fees, underwriters' or placement agents' fees, discounts or commissions and
brokerage, consultant and other fees incurred in connection with such issuance
or sale and net of taxes paid or payable as a result thereof.

                  "Non-U.S. Person" means a person who is not a U.S. person, as
defined in Regulation S.

                  "Note Register" has the meaning provided in Section 2.04.

                  "Notes" means any of the notes, as defined in the first
paragraph of the recitals hereof, that are authenticated and delivered under
this Indenture. For all purposes of this Indenture, the term "Notes" shall
include Exchange Notes to be issued and exchanged for any Notes pursuant to the
Registration Rights Agreement and this Indenture and, for purposes of this
Indenture, all Notes and Exchange Notes shall vote together as one series of
Notes under this Indenture.

                  "Offer to Purchase" means an offer to purchase Notes by the
Company from the Holders commenced by mailing a notice to the Trustee and each
Holder stating: (i) the covenant pursuant to which the offer is being made and
that all Notes validly tendered will be accepted for payment on a pro rata
basis; (ii) the purchase price and the date of purchase (which shall be a
Business Day no earlier than 30 days nor later than 60 days from the date

<PAGE>   16


                                       14

such notice is mailed) (the "Payment Date"); (iii) that any Note not tendered
will continue to accrue interest (or original issue discount) pursuant to its
terms; (iv) that, unless the Company defaults in the payment of the purchase
price, any Note accepted for payment pursuant to the Offer to Purchase shall
cease to accrue interest (or original issue discount) on and after the Payment
Date; (v) that Holders electing to have a Note purchased pursuant to the Offer
to Purchase will be required to surrender the Note, together with the form
entitled "Option of the Holder to Elect Purchase" on the reverse side of the
Note completed, to the Paying Agent at the address specified in the notice prior
to the close of business on the Business Day immediately preceding the Payment
Date; (vi) that Holders will be entitled to withdraw their election if the
Paying Agent receives, not later than the close of business on the third
Business Day immediately preceding the Payment Date, a telegram, facsimile
transmission or letter setting forth the name of such Holder, the principal
amount at maturity of Notes delivered for purchase and a statement that such
Holder is withdrawing his election to have such Notes purchased; and (vii) that
Holders whose Notes are being purchased only in part will be issued new Notes
equal in principal amount to the unpurchased portion of the Notes surrendered;
provided that each Note purchased and each new Note issued shall be in a
principal amount at maturity of $1,000 or integral multiples thereof. On the
Payment Date, the Company shall (i) accept for payment on a pro rata basis Notes
or portions thereof tendered pursuant to an Offer to Purchase; (ii) deposit with
the Paying Agent money sufficient to pay the purchase price of all Notes or
portions thereof so accepted; and (iii) deliver, or cause to be delivered, to
the Trustee all Notes or portions thereof so accepted together with an Officers'
Certificate specifying the Notes or portions thereof accepted for payment by the
Company. The Paying Agent shall promptly mail to the Holders of Notes so
accepted payment in an amount equal to the purchase price, and the Trustee shall
promptly authenticate and mail to such Holders a new Note equal in principal
amount at maturity to any unpurchased portion of the Note surrendered; provided
that each Note purchased and each new Note issued shall be in a principal amount
at maturity of $1,000 or integral multiples thereof. The Company will publicly
announce the results of an Offer to Purchase as soon as practicable after the
Payment Date. The Trustee shall act as the Paying Agent for an Offer to
Purchase. The Company will comply with Rule 14e-1 under the Exchange Act and any
other securities laws and regulations thereunder to the extent such laws and
regulations are applicable, in the event that the Company is required to
repurchase Notes pursuant to an Offer to Purchase.

                  "Officer" means, with respect to the Company, (i) the Chairman
of the Board, the President, any Vice President, the Chief Financial Officer,
and (ii) the Treasurer or any Assistant Treasurer, or the Secretary or any
Assistant Secretary.

                  "Officers' Certificate" means a certificate signed by one
Officer listed in clause (i) of the definition thereof and one Officer listed in
clause (ii) of the definition thereof. Each Officers' Certificate (other than
certificates provided pursuant to TIA Section 314(a)(4)) shall include the
statements provided for in TIA Section 314(e).

<PAGE>   17


                                       15


                  "Offshore Global Note" has the meaning provided in Section
2.01.

                  "Offshore Physical Notes" has the meaning provided in Section
2.01.

                  "Opinion of Counsel" means a written opinion signed by legal
counsel who may be an employee of or counsel to the Company. Each such Opinion
of Counsel shall include the statements provided for in TIA Section 314(e).

                  "Paying Agent" has the meaning provided in Section 2.04,
except that, for the purposes of Article Eight, the Paying Agent shall not be
the Company or a Subsidiary of the Company or an Affiliate of any of them. The
term "Paying Agent" includes any additional Paying Agent.

                  "Payment Blockage Period" has the meaning provided in Section
10.02.

                  "Permitted Investment" means (i) an Investment in the Company
or a Restricted Subsidiary or a Person which will, upon the making of such
Investment, become a Restricted Subsidiary or be merged or consolidated with or
into or transfer or convey all or substantially all its assets to, the Company
or a Restricted Subsidiary; provided that such person's primary business is
related, ancillary or complementary to the businesses of the Company and its
Restricted Subsidiaries on the date of such Investment; (ii) Temporary Cash
Investments; (iii) payroll, travel and similar advances to cover matters that
are expected at the time of such advances ultimately to be treated as expenses
in accordance with GAAP; (iv) stock, obligations or securities received in
satisfaction of judgments; and (v) Investments received as consideration in
Asset Sales to the extent permitted under Section 4.11.

                  "Person" means an individual, a corporation, a partnership, a
limited liability company, an association, a trust or any other entity or
organization, including a government or political subdivision or an agency or
instrumentality thereof.

                  "Physical Notes" has the meaning provided in Section 2.01.

                  "Preferred Stock" means, with respect to any Person, any and
all shares, interests, participations or other equivalents (however designated,
whether voting or non-voting) of such Person's preferred or preference stock,
whether now outstanding or issued after the date of the Indenture, including,
without limitation, all series and classes of such preferred or preference
stock.

                  "principal" of a debt security, including the Notes, means the
principal amount due on the Stated Maturity as shown on such debt security.

<PAGE>   18


                                       16

                  "Private Placement Legend" means the legend initially set
forth on the Notes in the form set forth in Section 2.02.

                  "Public Equity Offering" means an underwritten primary public
offering of Common Stock of the Company pursuant to an effective registration
statement under the Securities Act.

                  "QIB" means a "qualified institutional buyer" as defined in
Rule 144A.

                  "Redeemable Stock" means any class or series of Capital Stock
of any Person that by its terms or otherwise is (i) required to be redeemed
prior to the Stated Maturity of the Notes, (ii) redeemable at the option of the
holder of such class or series of Capital Stock at any time prior to the Stated
Maturity of the Notes or (iii) convertible into or exchangeable for Capital
Stock referred to in clause (i) or (ii) above or Indebtedness having a scheduled
maturity prior to the Stated Maturity of the Notes; provided that any Capital
Stock that would not constitute Redeemable Stock but for provisions thereof
giving holders thereof the right to require such Person to repurchase or redeem
such Capital Stock upon the occurrence of an "asset sale" or "change of control"
occurring prior to the Stated Maturity of the Notes shall not constitute
Redeemable Stock if the "asset sale" or "change of control" provisions
applicable to such Capital Stock are no more favorable to the holders of such
Capital Stock than the provisions contained in Sections 4.11 and 4.12 and such
Capital Stock specifically provides that such Person will not repurchase or
redeem any such stock pursuant to such provision prior to the Company's
repurchase of such Notes as are required to be repurchased pursuant to the
provisions of Sections 4.11 and 4.12.

                  "Redemption Date", when used with respect to any Note to be
redeemed, means the date fixed for such redemption by or pursuant to this
Indenture.

                  "Redemption Price", when used with respect to any Note to be
redeemed, means the price at which such Note is to be redeemed pursuant to this
Indenture.

                  "Registrar" has the meaning provided in Section 2.04.

                  "Registration Rights Agreement" means the Registration Rights
Agreement, dated as of January 28, 1998, between the Company and Morgan Stanley
& Co. Incorporated, and certain permitted assigns specified therein.

                  "Registration Statement" means the Registration Statement as
defined and described in the Registration Rights Agreement.

<PAGE>   19


                                       17

                  "Regular Record Date" for the interest payable on any Interest
Payment Date means the January 15 or July 15 (whether or not a Business Day), as
the case may be, next preceding such Interest Payment Date.

                  "Regulation S" means Regulation S under the Securities Act.

                  "Responsible Officer", when used with respect to the Trustee,
means the chairman or any vice chairman of the board of directors, the chairman
or any vice chairman of the executive committee of the board of directors, the
chairman of the trust committee, the president, any vice president, any
assistant vice president, the secretary, any assistant secretary, the treasurer,
any assistant treasurer, the cashier, any assistant cashier, any trust officer
or assistant trust officer, the controller or any assistant controller or any
other officer of the Trustee customarily performing functions similar to those
performed by any of the above designated officers and also means, with respect
to a particular corporate trust matter, any other officer to whom such matter is
referred because of his or her knowledge of and familiarity with the particular
subject.

                  "Restricted Payments" has the meaning provided in Section
4.06.

                  "Restricted Subsidiary" means any Subsidiary of the Company
other than an Unrestricted Subsidiary.

                  "Rule 144A" means Rule 144A under the Securities Act.

                  "Secured Indebtedness" has the meaning provided in Section
4.05.

                  "Securities Act" means the Securities Act of 1933, as amended.

                  "Senior Indebtedness" means the following obligations of the
Company, whether outstanding on the Closing Date or thereafter Incurred: (i) all
Indebtedness and all other monetary obligations (including expenses,
indemnities, fees and other monetary obligations) of the Company under the
Credit Agreement, any Interest Rate Agreement or Currency Agreement relating to
Indebtedness under the Credit Agreement, the 12 1/4% Notes, the 15% Notes and
the Vendor Financing Arrangement and (ii) all Indebtedness and all other
monetary obligations of the Company (other than the Notes), including principal
and interest on such Indebtedness, unless such Indebtedness, by its terms or by
the terms of any agreement or instrument pursuant to which such Indebtedness is
issued, is pari passu with, or subordinated in right of payment to, the Notes;
provided that the term "Senior Indebtedness" shall not include (a) any
Indebtedness of the Company that, when Incurred, was without recourse to the
Company, (b) any Indebtedness of the Company to a Subsidiary of the Company, or
to a joint venture in which the Company has an interest, (c) any Indebtedness of
the Company, to the extent not permitted by Section 4.03 or Section 4.04 (but as
to any

<PAGE>   20


                                       18

such Indebtedness under the Credit Agreement, no such violation shall be deemed
to exist for purposes of this clause (c) if the Bank Agent shall have received
an Officers' Certificate to the effect that the issuance of such Indebtedness
does not violate such covenant), (d) any Indebtedness to any employee of the
Company or any of its respective Subsidiaries, (e) any liability for taxes owed
or owing by the Company or (f) any Trade Payables. Senior Indebtedness will also
include interest accruing subsequent to events of bankruptcy of the Company and
its respective Subsidiaries at the rate provided for in the document governing
such Senior Indebtedness, whether or not such interest is an allowed claim
enforceable against the debtor in a bankruptcy case under bankruptcy law.

                  "Senior Subordinated Obligations" means any principal of,
premium, if any, or interest (including, without limitation, any additional
interest payable by reason of the Company's failure to consummate an exchange
offer to cause a shelf registration to become effective) on the Notes payable
pursuant to the terms of the Notes or upon acceleration, including any amounts
received upon the exercise of rights of rescission or other rights of action
(including claims for damages) or otherwise, to the extent relating to the
purchase price of the Notes or amounts corresponding to such principal, premium,
if any, or interest on the Notes.

                  "Significant Subsidiary" means, at any date of determination,
any Restricted Subsidiary that, together with its Subsidiaries, (i) for the most
recent fiscal year of the Company, accounted for more than 10% of the
consolidated revenues of the Company and its Restricted Subsidiaries or (ii) as
of the end of such fiscal year, was the owner of more than 10% of the
consolidated assets of the Company and its Restricted Subsidiaries, all as set
forth on the most recently available consolidated financial statements of the
Company for such fiscal year.

                  "Specified Date" means any Redemption Date, any Payment Date
for an Offer to Purchase or any date on which the Notes first become due and
payable after an Event of Default.

                  "S&P" means Standard & Poor's Ratings Services and its
successors.

                  "Stated Maturity" means, (i) with respect to any debt
security, the date specified in such debt security as the fixed date on which
the final installment of principal of such debt security is due and payable and
(ii) with respect to any scheduled installment of principal of or interest on
any debt security, the date specified in such debt security as the fixed date on
which such installment is due and payable.

                  "Subsidiary" means, with respect to any Person, any
corporation, association or other business entity of which more than 50% of the
voting power of the outstanding

<PAGE>   21


                                       19

Voting Stock is owned, directly or indirectly, by such Person and one or more
other Subsidiaries of such Person.

                  "Subsidiary Guarantee" has the meaning provided in Section
4.09.

                  "Temporary Cash Investment" means any of the following: (i)
direct obligations of the United States of America or any agency thereof or
obligations fully and unconditionally guaranteed by the United States of America
or any agency thereof, (ii) time deposit accounts, certificates of deposit and
money market deposits maturing within 180 days of the date of acquisition
thereof issued by a bank or trust company which is organized under the laws of
the United States of America, any state thereof or any foreign country
recognized by the United States of America, and which bank or trust company has
capital, surplus and undivided profits aggregating in excess of $50 million (or
the foreign currency equivalent thereof) and has outstanding debt which is rated
"A" (or such similar equivalent rating) or higher by at least one nationally
recognized statistical rating organization (as defined in Rule 436 under the
Securities Act) or any money-market fund sponsored by a registered broker dealer
or mutual fund distributor, (iii) repurchase obligations with a term of not more
than 30 days for underlying securities of the types described in clause (i)
above entered into with a bank meeting the qualifications described in clause
(ii) above, (iv) commercial paper, maturing not more than 90 days after the date
of acquisition, issued by a corporation (other than an Affiliate of the Company)
organized and in existence under the laws of the United States of America, any
state thereof or any foreign country recognized by the United States of America
with a rating at the time as of which any investment therein is made of "P-1"
(or higher) according to Moody's or "A-1" (or higher) according to S&P, and (v)
securities with maturities of six months or less from the date of acquisition
issued or fully and unconditionally guaranteed by any state, commonwealth or
territory of the United States of America, or by any political subdivision or
taxing authority thereof, and rated at least "A" by S&P or Moody's.

                  "TIA" or "Trust Indenture Act" means the Trust Indenture Act
of 1939, as amended (15 U.S. Code Sections 77aaa-77bbb), as in effect on
the date this Indenture was executed, except as provided in Section 9.06.

                  "Trade Payables" means, with respect to any Person, any
accounts payable or any other indebtedness or monetary obligation to trade
creditors created, assumed or Guaranteed by such Person or any of its
Subsidiaries arising in the ordinary course of business in connection with the
acquisition of goods or services.

                  "Transaction Date" means, with respect to the Incurrence of
any Indebtedness by the Company or any of its Restricted Subsidiaries, the date
such Indebtedness is to be Incurred and, with respect to any Restricted Payment,
the date such Restricted Payment is to be made.

<PAGE>   22


                                       20


                  "Trustee" means the party named as such in the first paragraph
of this Indenture until a successor replaces it in accordance with the
provisions of Article Seven of this Indenture and thereafter means such
successor.

                  "United States Bankruptcy Code" means the Bankruptcy Reform
Act of 1978, as amended and as codified in Title 11 of the United States Code,
as amended from time to time hereafter, or any successor federal bankruptcy law.

                  "Unrestricted Subsidiary" means (i) any Subsidiary of the
Company that at the time of determination shall be designated an Unrestricted
Subsidiary by the Board of Directors in the manner provided below; and (ii) any
Subsidiary of an Unrestricted Subsidiary. The Board of Directors may designate
any Restricted Subsidiary (including any newly acquired or newly formed
Subsidiary of the Company) to be an Unrestricted Subsidiary unless such
Subsidiary owns any Capital Stock of, or owns or holds any Lien on any property
of, the Company or any Restricted Subsidiary; provided that (A) any Guarantee by
the Company or any Restricted Subsidiary of any Indebtedness of the Subsidiary
being so designated shall be deemed an "Incurrence" of such Indebtedness and an
"Investment" by the Company or such Restricted Subsidiary (or both, if
applicable) at the time of such designation; (B) either (I) the Subsidiary to be
so designated has total assets of $1,000 or less or (II) if such Subsidiary has
assets greater than $1,000, such designation would be permitted under Section
4.06 and (C) if applicable, the Incurrence of Indebtedness and the Investment
referred to in clause (A) of this proviso would be permitted under Sections 4.03
and 4.06. The Board of Directors may designate any Unrestricted Subsidiary to be
a Restricted Subsidiary; provided that (i) no Default or Event of Default shall
have occurred and be continuing at the time of or after giving effect to such
designation and (ii) all Liens and Indebtedness of such Unrestricted Subsidiary
outstanding immediately after such designation would, if Incurred at such time,
have been permitted to be Incurred (and shall be deemed to have been Incurred)
for all purposes of the Indenture. Any such designation by the Board of
Directors shall be evidenced to the Trustee by promptly filing with the Trustee
a copy of the Board Resolution giving effect to such designation and an
Officers' Certificate certifying that such designation complied with the
foregoing provisions.

                  "U.S. Global Note" has the meaning provided in Section 2.01.

                  "U.S. Government Obligations" means securities that are (i)
direct obligations of the United States of America for the payment of which its
full faith and credit is pledged or (ii) obligations of a Person controlled or
supervised by and acting as an agency or instrumentality of the United States of
America the payment of which is unconditionally guaranteed as a full faith and
credit obligation by the United States of America, which, in either case, are
not callable or redeemable at the option of the issuer thereof at any time prior
to the Stated Maturity of the Notes, and shall also include a depository receipt
issued by a bank or trust company as custodian with respect to any such U.S.
Government

<PAGE>   23


                                       21

Obligation or a specific payment of interest on or principal of any such U.S.
Government Obligation held by such custodian for the account of the holder of a
depository receipt; provided that (except as required by law) such custodian is
not authorized to make any deduction from the amount payable to the holder of
such depository receipt from any amount received by the custodian in respect of
the U.S. Government Obligation or the specific payment of interest on or
principal of the U.S. Government Obligation evidenced by such depository
receipt.

                  "U.S. Physical Notes" has the meaning provided in Section
2.01.

                  "Vendor Financing Arrangement" means the Financing and
Security Agreement between Glenayre Electronics Inc. and the Company dated March
21, 1997, as amended from time to time.

                  "Voting Stock" means with respect to any Person, Capital Stock
of any class or kind ordinarily having the power to vote for the election of
directors, managers or other voting members of the governing body of such
Person.

                  "Warrant Agreement" means the Warrant Agreement dated as of
October 19, 1993 between the Company and United States Trust Company of New
York, as warrant agent.

                  "Warrants" means the warrants issued under the Warrant
Agreement, each of which entitles the holder thereof to purchase one share of
Common Stock of the Company at a price of $3.26 per share, subject to
adjustment.

                  "Wholly Owned" means, with respect to any Subsidiary of any
Person, the ownership of all of the outstanding Capital Stock of such Subsidiary
(other than any director's qualifying shares or Investments by foreign nationals
mandated by applicable law) by such Person or one or more Wholly Owned
Subsidiaries of such Person.

                  SECTION 1.02. Incorporation by Reference of Trust Indenture
Act. Whenever this Indenture refers to a provision of the TIA, the provision is
incorporated by reference in and made a part of this Indenture. The following
TIA terms used in this Indenture have the following meanings:

                  "indenture securities" means the Notes;

                  "indenture security holder" means a Holder;

                  "indenture to be qualified" means this Indenture;

<PAGE>   24


                                       22

                  "indenture trustee" or "institutional trustee" means the
Trustee; and

                  "obligor" on the indenture securities means the Company or any
other obligor on the Notes.

                  All other TIA terms used in this Indenture that are defined by
the TIA, defined by TIA reference to another statute or defined by a rule of the
Commission and not otherwise defined herein have the meanings assigned to them
therein.

                  SECTION 1.03.  Rules of Construction.  Unless the context
otherwise requires:

                  (i)      a term has the meaning assigned to it;

                  (ii) an accounting term not otherwise defined has the meaning
         assigned to it in accordance with GAAP;

                  (iii)    "or" is not exclusive;

                  (iv) words in the singular include the plural, and words in
         the plural include the singular;

                  (v)      provisions apply to successive events and
         transactions;

                  (vi) "herein", "hereof" and other words of similar import
         refer to this Indenture as a whole and not to any particular Article,
         Section or other subdivision;

                  (vii) all ratios and computations based on GAAP contained in
         this Indenture shall be computed in accordance with the definition of
         GAAP set forth in Section 1.01; and

                  (viii) all references to Sections or Articles refer to
         Sections or Articles of this Indenture unless otherwise indicated.


                                   ARTICLE TWO
                                    THE NOTES

                  SECTION 2.01. Form and Dating. The Notes and the Trustee's
certificate of authentication shall be substantially in the form annexed hereto
as Exhibit A. The Notes may have notations, legends or endorsements required by
law, stock exchange agreements to which the Company is subject or usage. The
Company shall approve the form of the Notes

<PAGE>   25


                                       23

and any notation, legend or endorsement on the Notes. Each Note shall be dated
the date of its authentication.

                  The terms and provisions contained in the form of the Notes
annexed hereto as Exhibit A shall constitute, and are hereby expressly made, a
part of this Indenture. To the extent applicable, the Company and the Trustee,
by their execution and delivery of this Indenture, expressly agree to such terms
and provisions and to be bound thereby.

                  Notes offered and sold in reliance on Rule 144A shall be
issued initially in the form of one or more permanent global Notes in registered
form, substantially in the form set forth in Exhibit A (the "U.S. Global
Notes"), deposited with the Trustee, as custodian for the Depositary, duly
executed by the Company and authenticated by the Trustee as hereinafter
provided. The aggregate principal amount of the U.S. Global Notes may from time
to time be increased or decreased by adjustments made on the records of the
Trustee, as custodian for the Depositary or its nominee, as hereinafter
provided.

                  Notes offered and sold in offshore transactions in reliance on
Regulation S shall be issued initially in the form of one or more permanent
global Notes in registered form substantially in the form set forth in Exhibit A
(the "Offshore Global Notes") deposited with the Trustee, as custodian for the
Depositary, duly executed by the Company and authenticated by the Trustee as
hereinafter provided. The aggregate principal amount of the Offshore Global
Notes may from time to time be increased or decreased by adjustments made on the
records of the Trustee, as custodian for the Depositary or its nominee, as
hereinafter provided.

                  Notes offered and sold in reliance on Regulation D under the
Securities Act shall be issued in the form of permanent certificated Notes in
registered form in substantially the form set forth in Exhibit A (the "U.S.
Physical Notes"). Notes issued pursuant to Section 2.07 in exchange for
interests in the Offshore Global Notes shall be in the form of permanent
certificated Notes in registered form substantially in the form set forth in
Exhibit A (the "Offshore Physical Notes").

                  The Offshore Physical Notes and U.S. Physical Notes are
sometimes collectively herein referred to as the "Physical Notes". The U.S.
Global Note and the Offshore Global Note are sometimes referred to herein as the
"Global Notes".

                  The definitive Notes shall be typed, printed, lithographed or
engraved or produced by any combination of these methods or may be produced in
any other manner permitted by the rules of any securities exchange on which the
Notes may be listed, all as determined by the Officers executing such Notes, as
evidenced by their execution of such Notes.


<PAGE>   26


                                       24

                  SECTION 2.02. Restrictive Legends. Unless and until a Note is
exchanged for an Exchange Note in connection with an effective Registration
Statement pursuant to the Registration Rights Agreement, (i) each U.S. Global
Note and each U.S. Physical Note shall bear the legend, set forth below on the
face thereof and (ii) each Offshore Physical Note and each Offshore Global Note
shall bear the legend set forth below on the face thereof until at least the
41st day after the Closing Date and receipt by the Company and the Trustee of a
certificate substantially in the form of Exhibit B hereto.

         THIS NOTE HAS NOT BEEN REGISTERED UNDER THE U.S. SECURITIES ACT OF
         1933, AS AMENDED (THE "SECURITIES ACT"), AND ACCORDINGLY, MAY NOT BE
         OFFERED OR SOLD WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR
         BENEFIT OF, U.S. PERSONS EXCEPT AS SET FORTH IN THE FOLLOWING SENTENCE.
         BY ITS ACQUISITION HEREOF, THE HOLDER (1) REPRESENTS THAT (A) IT IS A
         "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A UNDER THE
         SECURITIES ACT) OR (B) IT IS AN INSTITUTIONAL "ACCREDITED INVESTOR" (AS
         DEFINED IN RULE 501(a)(1), (2), (3) OR (7) OF REGULATION D UNDER THE
         SECURITIES ACT) (AN "INSTITUTIONAL ACCREDITED INVESTOR") OR (C) IT IS
         NOT A U.S. PERSON AND IS ACQUIRING THIS NOTE IN AN OFFSHORE TRANSACTION
         IN COMPLIANCE WITH REGULATION S UNDER THE SECURITIES ACT, (2) AGREES
         THAT IT WILL NOT, WITHIN THE TIME PERIOD REFERRED TO IN RULE 144(k)
         UNDER THE SECURITIES ACT AS IN EFFECT ON THE DATE OF TRANSFER OF SUCH
         NOTE RESELL OR OTHERWISE TRANSFER THIS NOTE EXCEPT (A) TO THE COMPANY
         OR ANY SUBSIDIARY THEREOF, (B) INSIDE THE UNITED STATES TO A QUALIFIED
         INSTITUTIONAL BUYER IN COMPLIANCE WITH RULE 144A UNDER THE SECURITIES
         ACT, (C) INSIDE THE UNITED STATES TO AN INSTITUTIONAL ACCREDITED
         INVESTOR THAT, PRIOR TO SUCH TRANSFER, FURNISHES TO THE TRUSTEE A
         SIGNED LETTER CONTAINING CERTAIN REPRESENTATIONS AND AGREEMENTS
         RELATING TO THE RESTRICTIONS ON TRANSFER OF THIS NOTE (THE FORM OF
         WHICH LETTER CAN BE OBTAINED FROM THE TRUSTEE) AND IF SUCH TRANSFER IS
         IN RESPECT OF AN ACCRETED VALUE OF NOTES AT THE TIME OF TRANSFER OF
         LESS THAN $100,000, AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY
         THAT SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT, (D)
         OUTSIDE THE UNITED STATES IN AN OFFSHORE TRANSACTION IN COMPLIANCE WITH
         RULE 904 UNDER THE SECURITIES ACT, (E) PURSUANT TO THE EXEMPTION FROM
         REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF
         AVAILABLE) OR (F) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER
         THE SECURITIES ACT AND (3) AGREES THAT IT WILL DELIVER TO EACH PERSON
         TO WHOM THIS NOTE

<PAGE>   27


                                       25

         IS TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. IN
         CONNECTION WITH ANY TRANSFER OF THIS NOTE WITHIN THE TIME PERIOD
         REFERRED TO ABOVE, THE HOLDER MUST CHECK THE APPROPRIATE BOX SET FORTH
         ON THE REVERSE HEREOF RELATING TO THE MANNER OF SUCH TRANSFER AND
         SUBMIT THIS CERTIFICATE TO THE TRUSTEE. IF THE PROPOSED TRANSFEREE IS
         AN INSTITUTIONAL ACCREDITED INVESTOR, THE HOLDER MUST, PRIOR TO SUCH
         TRANSFER, FURNISH TO THE TRUSTEE AND THE COMPANY SUCH CERTIFICATIONS,
         LEGAL OPINIONS OR OTHER INFORMATION AS EITHER OF THEM MAY REASONABLY
         REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING MADE PURSUANT TO AN
         EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
         REQUIREMENTS OF THE SECURITIES ACT. AS USED HEREIN, THE TERMS "OFFSHORE
         TRANSACTION," "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN
         TO THEM BY REGULATION S UNDER THE SECURITIES ACT. THE INDENTURE
         CONTAINS A PROVISION REQUIRING THE TRUSTEE TO REFUSE TO REGISTER ANY
         TRANSFER OF THIS NOTE IN VIOLATION OF THE FOREGOING RESTRICTIONS.

                  Each Global Note, whether or not an Exchange Note, shall also
bear the following legend on the face thereof:

         UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
         THE DEPOSITORY TRUST COMPANY TO THE COMPANY OR ITS AGENT FOR
         REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE
         ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR TO SUCH OTHER ENTITY
         AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST
         COMPANY OR SUCH OTHER REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY OR
         SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE
         DEPOSITORY TRUST COMPANY (AND ANY PAYMENT HEREON IS MADE TO CEDE & CO.
         OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE
         OF THE DEPOSITORY TRUST COMPANY), 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.

         TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS IN WHOLE,
         BUT NOT IN PART, TO NOMINEES OF CEDE & CO. OR TO A SUCCESSOR THEREOF
         OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS GLOBAL
         NOTE SHALL BE LIMITED TO TRANSFERS

<PAGE>   28


                                       26

         MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH IN SECTION 2.08 OF
         THE INDENTURE.

                  SECTION 2.03. Execution, Authentication and Denominations.
Subject to Article Four, the aggregate principal amount of Notes which may be
authenticated and delivered under this Indenture is unlimited. The Notes shall
be executed by an Officer of the Company listed in clause (i) of the definition
of Officer herein and attested by its Secretary, any Assistant Secretary, the
Treasurer or any Assistant Treasurer. The signature of any of these Officers on
the Notes may be by facsimile or manual signature, in the name and on behalf of
the Company.

                  If an Officer whose signature is on a Note no longer holds
that office at the time the Trustee or authenticating agent authenticates the
Note, the Note shall be valid nevertheless.

                  A Note shall not be valid until the Trustee or authenticating
agent manually signs the certificate of authentication on the Note. The
signature shall be conclusive evidence that the Note has been authenticated
under this Indenture.

                  At any time and from time to time after the execution of this
Indenture, the Trustee or an authenticating agent shall upon receipt of a
Company Order authenticate for original issue Notes in the aggregate principal
amount specified in such Company Order; provided that the Trustee shall be
entitled to receive an Officers' Certificate and an Opinion of Counsel of the
Company that it may reasonably request in connection with such authentication of
Notes. Such Company Order shall specify the amount of Notes to be authenticated,
the date on which the original issue of Notes is to be authenticated and the
aggregate principal amount of Notes then authorized and in case of an issuance
of Notes pursuant to Section 2.15, shall certify that such issuance is in
compliance with Article Four.

                  The Trustee may appoint an authenticating agent to
authenticate Notes. If the appointment of such authenticating agent is not at
the discretion and for the convenience of the Trustee, then such authenticating
agent shall be compensated by the Company. An authenticating agent may
authenticate Notes whenever the Trustee may do so. Each reference in this
Indenture to authentication by the Trustee includes authentication by such
authenticating agent. An authenticating agent has the same rights as an Agent to
deal with the Company or an Affiliate of the Company.

                  The Notes shall be issuable only in registered form without
coupons and only in denominations of $1,000 in principal amount and any integral
multiple thereof.

                  SECTION 2.04.  Registrar and Paying Agent.  The Company shall
maintain an office or agency where Notes may be presented for registration of
transfer or for

<PAGE>   29


                                       27

exchange (the "Registrar"), an office or agency where Notes may be presented for
payment (the "Paying Agent") and an office or agency where notices and demands
to or upon the Company in respect of the Notes and this Indenture may be served,
which shall be in the Borough of Manhattan, The City of New York. The Company
shall cause the Registrar to keep a register of the Notes and of their transfer
and exchange (the "Note Register"). The Note Register shall be in written form
or any other form capable of being converted into written form within a
reasonable time. The Company may have one or more co-Registrars and one or more
additional Paying Agents.

                  The Company shall enter into an appropriate agency agreement
with any Agent not a party to this Indenture. The agreement shall implement the
provisions of this Indenture that relate to such Agent. The Company shall give
prompt written notice to the Trustee of the name and address of any such Agent
and any change in the address of such Agent. If the Company fails to maintain a
Registrar, Paying Agent and/or agent for service of notices and demands, the
Trustee shall act as such Registrar, Paying Agent and/or agent for service of
notices and demands. The Company may remove any Agent upon written notice to
such Agent and the Trustee; provided that no such removal shall become effective
until (i) the acceptance of an appointment by a successor Agent to such Agent as
evidenced by an appropriate agency agreement entered into by the Company and
such successor Agent and delivered to the Trustee or (ii) notification to the
Trustee that the Trustee shall serve as such Agent until the appointment of a
successor Agent in accordance with clause (i) of this proviso. The Company, any
Subsidiary of the Company, or any Affiliate of any of them may act as Paying
Agent, Registrar or co-Registrar, and/or agent for service of notice and
demands.

                  The Company initially appoints the Trustee as Registrar,
Paying Agent, authenticating agent and agent for service of notice and demands.
If, at any time, the Trustee is not the Registrar, the Registrar shall make
available to the Trustee at least seven Business Days before each Interest
Payment Date and at such other times as the Trustee may reasonably request, the
names and addresses of the Holders as they appear in the Note Register. At the
option of the Company, payment of interest may be made by check mailed to the
address of the Holders as such address appears in the Note Register.

                  SECTION 2.05. Paying Agent to Hold Money in Trust. Not later
than each due date of the principal, premium, if any, and interest on any Notes,
the Company shall deposit with the Paying Agent money in immediately available
funds sufficient to pay such principal, premium, if any, and interest so
becoming due. The Company shall require each Paying Agent other than the Trustee
to agree in writing that such Paying Agent shall hold in trust for the benefit
of the Holders or the Trustee all money held by the Paying Agent for the payment
of principal of, premium, if any, and interest on the Notes (whether such money
has been paid to it by the Company or any other obligor on the Notes), and such
Paying Agent shall promptly notify the Trustee of any default by the Company (or
any other obligor on the

<PAGE>   30


                                       28

Notes) in making any such payment. The Company at any time may require a Paying
Agent to pay all money held by it to the Trustee and account for any funds
disbursed, and the Trustee may at any time during the continuance of any payment
default, upon written request to a Paying Agent, require such Paying Agent to
pay all money held by it to the Trustee and to account for any funds disbursed.
Upon doing so, the Paying Agent shall have no further liability for the money so
paid over to the Trustee. If the Company or any Subsidiary of the Company or any
Affiliate of any of them acts as Paying Agent, it will, on or before each due
date of any principal of, premium, if any, or interest on the Notes, segregate
and hold in a separate trust fund for the benefit of the Holders a sum of money
sufficient to pay such principal, premium, if any, or interest so becoming due
until such sum of money shall be paid to such Holders or otherwise disposed of
as provided in this Indenture, and will promptly notify the Trustee of its
action or failure to act.

                  SECTION 2.06. Transfer and Exchange. The Notes are issuable
only in registered form. A Holder may transfer a Note by written application to
the Registrar stating the name of the proposed transferee and otherwise
complying with the terms of this Indenture. No such transfer shall be effected
until, and such transferee shall succeed to the rights of a Holder only upon,
final acceptance and registration of the transfer by the Registrar in the Note
Register. Prior to the registration of any transfer by a Holder as provided
herein, the Company, the Trustee, and any agent of the Company shall treat the
person in whose name the Note is registered as the owner thereof for all
purposes whether or not the Note shall be overdue, and neither the Company, the
Trustee, nor any such agent shall be affected by notice to the contrary.
Furthermore, any Holder of a Global Note shall, by acceptance of such Global
Note, agree that transfers of beneficial interests in such Global Note may be
effected only through a book entry system maintained by the Holder of such
Global Note (or its agent) and that ownership of a beneficial interest in the
Note shall be required to be reflected in a book entry. When Notes are presented
to the Registrar or a co- Registrar with a request to register the transfer or
to exchange them for an equal principal amount of Notes of other authorized
denominations (including an exchange of Notes for Exchange Notes), the Registrar
shall register the transfer or make the exchange as requested if its
requirements for such transactions are met; provided that no exchanges of Notes
for Exchange Notes shall occur until a Registration Statement shall have been
declared effective by the Commission and that any Notes that are exchanged for
Exchange Notes shall be cancelled by the Trustee. To permit registrations of
transfers and exchanges, the Company shall execute and the Trustee shall
authenticate Notes at the Registrar's request. No service charge shall be made
for any registration of transfer or exchange or redemption of the Notes, but the
Company may require payment of a sum sufficient to cover any transfer tax or
similar governmental charge payable in connection therewith (other than any such
transfer taxes or other similar governmental charge payable upon exchanges
pursuant to Section 2.11, 3.08 or 9.04).

<PAGE>   31


                                       29

                  The Registrar shall not be required (i) to issue, register the
transfer of or exchange any Note during a period beginning at the opening of
business 15 days before the day of the mailing of a notice of redemption of
Notes selected for redemption under Section 3.03 and ending at the close of
business on the day of such mailing, or (ii) to register the transfer of or
exchange any Note so selected for redemption in whole or in part, except the
unredeemed portion of any Note being redeemed in part.

                  SECTION 2.07. Book-Entry Provisions for Global Notes. (a) The
U.S. Global Notes and Offshore Global Notes initially shall (i) be registered in
the name of the Depositary for such Global Notes or the nominee of such
Depositary, (ii) be delivered to the Trustee as custodian for such Depositary
and (iii) bear legends as set forth in Section 2.02.

                  Members of, or participants in, the Depositary ("Agent
Members") shall have no rights under this Indenture with respect to any Global
Note held on their behalf by the Depositary, or the Trustee as its custodian, or
under the Global Note, and the Depositary may be treated by the Company, the
Trustee and any agent of the Company or the Trustee as the absolute owner of
such Global Note for all purposes whatsoever. Notwithstanding the foregoing,
nothing herein shall prevent the Company, the Trustee or any agent of the
Company or the Trustee, from giving effect to any written certification, proxy
or other authorization furnished by the Depositary or impair, as between the
Depositary and its Agent Members, the operation of customary practices governing
the exercise of the rights of a holder of any Note.

                  (b) Transfers of a Global Note shall be limited to transfers
of such Global Note in whole, but not in part, to the Depositary, its successors
or their respective nominees. Interests of beneficial owners in a Global Note
may be transferred in accordance with the rules and procedures of the Depositary
and the provisions of Section 2.08. In addition, U.S. Physical Notes and
Offshore Physical Notes shall be transferred to all beneficial owners in
exchange for their beneficial interests in the U.S. Global Notes or the Offshore
Global Notes, respectively, if (i) the Depositary notifies the Company that it
is unwilling or unable to continue as Depositary for the U.S. Global Notes or
the Offshore Global Notes, as the case may be, and a successor depositary is not
appointed by the Company within 90 days of such notice or (ii) an Event of
Default has occurred and is continuing and the Registrar has received a request
to the foregoing effect from the Depositary.

                  (c) Any beneficial interest in one of the Global Notes that is
transferred to a person who takes delivery in the form of an interest in the
other Global Note will, upon transfer, cease to be an interest in such Global
Note and become an interest in the other Global Note and, accordingly, will
thereafter be subject to all transfer restrictions, if any, and other procedures
applicable to beneficial interests in such other Global Note for as long as it
remains such an interest.

<PAGE>   32


                                       30

                  (d) In connection with any transfer of a portion of the
beneficial interests in a U.S. Global Note or Offshore Global Note to beneficial
owners pursuant to paragraph (b) of this Section, the Registrar shall reflect on
its books and records the date and a decrease in the principal amount of the
U.S. Global Notes or Offshore Global Notes in an amount equal to the principal
amount of the beneficial interest in such Global Notes to be transferred, and
the Company shall execute, and the Trustee shall authenticate and deliver, one
or more U.S. Physical Notes or Offshore Physical Notes, as the case may be, of
like tenor and amount.

                  (e) In connection with the transfer of the entire U.S. Global
Note or Offshore Global Note to beneficial owners pursuant to paragraph (b) of
this Section, the U.S. Global Note or Offshore Global Note, as the case may be,
shall be deemed to be surrendered to the Trustee for cancellation, and the
Company shall execute, and the Trustee shall authenticate and deliver, to each
beneficial owner identified by the Depositary in exchange for its beneficial
interest in the U.S. Global Note or Offshore Global Note, as the case may be, an
equal aggregate principal amount of U.S. Physical Notes or Offshore Physical
Notes, as the case may be, of authorized denominations.

                  (f) Any U.S. Physical Note delivered in exchange for an
interest in the U.S. Global Note pursuant to paragraph (b), (d) or (e) of this
Section shall, except as otherwise provided by paragraph (e) of Section 2.08,
bear the legend regarding transfer restrictions applicable to the U.S. Physical
Note set forth in Section 2.02.

                  (g) Any Offshore Physical Note delivered in exchange for an
interest in the Offshore Global Note pursuant to paragraph (b), (d) or (e) of
this Section shall, except as otherwise provided by paragraph (e) of Section
2.08, bear the legend regarding transfer restrictions applicable to the Offshore
Physical Note set forth in Section 2.02.

                  (h) The registered holder of a Global Note may grant proxies
and otherwise authorize any person, including Agent Members and persons that may
hold interests through Agent Members, to take any action which a Holder is
entitled to take under this Indenture or the Notes.

                  (i) Beneficial owners of interests in a U.S. Global Note may
receive U.S. Physical Notes (which shall bear the Private Placement Legend if
required by Section 2.02) in accordance with the procedures of the Depositary.
In connection with the execution, authentication and delivery of such U.S.
Physical Notes, the Registrar shall reflect on its books and records a decrease
in the principal amount of the relevant U.S. Global Note equal to the principal
amount of such U.S. Physical Notes and the Company shall execute and the Trustee
shall authenticate and deliver one or more U.S. Physical Notes having an equal
aggregate principal amount.

<PAGE>   33


                                       31

                  SECTION 2.08. Special Transfer Provisions. Unless and until a
Note is exchanged for an Exchange Note in connection with an effective
Registration Statement pursuant to the Registration Rights Agreement, the
following provisions shall apply:

                  (a) Transfers to Non-QIB Institutional Accredited Investors.
The following provisions shall apply with respect to the registration of any
proposed transfer of a Note to any Institutional Accredited Investor which is
not a QIB (excluding Non-U.S. Persons):

                  (i) The Registrar shall register the transfer of any Note,
         whether or not such Note bears the Private Placement Legend, if (x) the
         requested transfer is after the time period referred to in Rule 144(k)
         under the Securities Act as in effect with respect to such transfer or
         (y) the proposed transferee has delivered to the Registrar (A) a
         certificate substantially in the form of Exhibit C hereto and (B) if
         the Accreted Value of the Notes being transferred is less than $100,000
         at the time of such transfer, an opinion of counsel acceptable to the
         Company that such transfer is in compliance with the Securities Act.

                  (ii) If the proposed transferor is an Agent Member holding a
         beneficial interest in the U.S. Global Note, upon receipt by the
         Registrar of (x) the documents, if any, required by paragraph (i) and
         (y) instructions given in accordance with the Depositary's and the
         Registrar's procedures, the Registrar shall reflect on its books and
         records the date and a decrease in the principal amount of the U.S.
         Global Note in an amount equal to the principal amount of the
         beneficial interest in the U.S. Global Note to be transferred, and the
         Company shall execute, and the Trustee shall authenticate and deliver,
         one or more U.S. Physical Notes of like tenor and amount.

                  (b) Transfers to QIBs. The following provisions shall apply
with respect to the registration of any proposed transfer of a U.S. Physical
Note, an interest in a U.S. Global Note or an interest in an Offshore Global
Note prior to the removal of the Private Placement Legend to a QIB (excluding
Non-U.S. Persons):

                  (i) If the Note to be transferred consists of (x) either (A)
         an interest in a Offshore Global Note prior to the removal of the
         Private Placement Legend or (B) U.S. Physical Notes, the Registrar
         shall register the transfer if such transfer is being made by a
         proposed transferor who has checked the box provided for on the form of
         Note stating, or has otherwise advised the Company and the Registrar in
         writing, that the sale has been made in compliance with the provisions
         of Rule 144A to a transferee who has signed the certification provided
         for on the form of Note stating, or has otherwise advised the Company
         and the Registrar in writing, that it is purchasing the Note for its
         own account or an account with respect to which it exercises sole
         investment discretion and that it and any such account is a QIB within
         the meaning of Rule 144A, and is aware that the sale to it is being
         made in reliance

<PAGE>   34


                                       32

         on Rule 144A and acknowledges that it has received such information
         regarding the Company as it has requested pursuant to Rule 144A or has
         determined not to request such information and that it is aware that
         the transferor is relying upon its foregoing representations in order
         to claim the exemption from registration provided by Rule 144A or (y)
         an interest in the U.S. Global Notes, the transfer of such interest may
         be effected only through the book entry system maintained by the
         Depositary.

                  (ii) If the proposed transferee is an Agent Member, and the
         Note to be transferred consists of U.S. Physical Notes, upon receipt by
         the Registrar of the documents referred to in clause (i) and
         instructions given in accordance with the Depositary's and the
         Registrar's procedures, the Registrar shall reflect on its books and
         records the date and an increase in the principal amount of the U.S.
         Global Notes in an amount equal to the principal amount of the U.S.
         Physical Notes, to be transferred, and the Trustee shall cancel the
         U.S. Physical Notes so transferred.

                  (c) Transfers of Interests in the Offshore Global Note or
Offshore Physical Notes. The following provisions shall apply with respect to
any transfer of interests in the Offshore Global Notes or Offshore Physical
Notes:

                  (i) prior to the removal of the Private Placement Legend from
         a Offshore Global Note or Offshore Physical Note pursuant to Section
         2.02, the Registrar shall refuse to register such transfer unless such
         transfer complies with Section 2.08(b) or Section 2.08(d), as the case
         may be; and

                  (ii) after such removal, the Registrar shall register the
         transfer of any such Note without requiring any additional
         certification.

                  (d) Transfers to Non-U.S. Persons at Any Time. The following
provisions shall apply with respect to any transfer of a Note to a Non-U.S.
Person:

                  (i) The Registrar shall register any proposed transfer to any
         Non-U.S. Person if the Note to be transferred is a U.S. Physical Note
         or an interest in the U.S. Global Note only upon receipt of a
         certificate substantially in the form of Exhibit D from the proposed
         transferor.

                  (ii) (a) If the proposed transferor is an Agent Member holding
         a beneficial interest in a U.S. Global Note, upon receipt by the
         Registrar of (x) the documents required by paragraph (i) and (y)
         instructions in accordance with the Depositary's and the Registrar's
         procedures, the Registrar shall reflect on its books and records the
         date and a decrease in the principal amount of such U.S. Global Note in
         an amount equal to the principal amount of the beneficial interest in
         the U.S. Global Note to be transferred, and (b) if the proposed
         transferee is an Agent Member, upon receipt by

<PAGE>   35


                                       33

         the Registrar of instructions given in accordance with the Depositary's
         and the Registrar's procedures, the Registrar shall reflect on its
         books and records the date and an increase in the principal amount of
         the Offshore Global Note in an amount equal to the principal amount of
         the U.S. Physical Notes or the U.S. Global Note, as the case may be, to
         be transferred, and the Trustee shall cancel the Physical Note, if any,
         so transferred or decrease the amount of the U.S. Global Note.

                  (e) Private Placement Legend. Upon the transfer, exchange or
replacement of Notes not bearing the Private Placement Legend, the Registrar
shall deliver Notes that do not bear the Private Placement Legend. Upon the
transfer, exchange or replacement of Notes bearing the Private Placement Legend,
the Registrar shall deliver only Notes that bear the Private Placement Legend
unless either (i) the circumstances contemplated by paragraphs (a)(i)(x) or
(c)(ii) of this Section 2.08 exist or (ii) there is delivered to the Registrar
an Opinion of Counsel reasonably satisfactory to the Company and the Trustee to
the effect that neither such legend nor the related restrictions on transfer are
required in order to maintain compliance with the provisions of the Securities
Act.

                  (f) General. By its acceptance of any Note bearing the Private
Placement Legend, each Holder of such a Note acknowledges the restrictions on
transfer of such Note set forth in this Indenture and in the Private Placement
Legend and agrees that it will transfer such Note only as provided in this
Indenture. The Registrar shall not register a transfer of any Note unless such
transfer complies with the restrictions on transfer of such Note set forth in
this Indenture. In connection with any transfer of Notes, each Holder agrees by
its acceptance of the Notes to furnish the Registrar or the Company such
certifications, legal opinions or other information as either of them may
reasonably require to confirm that such transfer is being made pursuant to an
exemption from, or a transaction not subject to, the registration requirements
of the Securities Act; provided that the Registrar shall not be required to
determine (but may conclusively rely on a determination made by the Company with
respect to) the sufficiency of any such certifications, legal opinions or other
information.

                  The Registrar shall retain copies of all letters, notices and
other written communications received pursuant to Section 2.07 or this Section
2.08. The Company shall have the right to inspect and make copies of all such
letters, notices or other written communications at any reasonable time upon the
giving of reasonable written notice to the Registrar.

                  SECTION 2.09. Replacement Notes. If a mutilated Note is
surrendered to the Trustee or if the Holder claims that the Note has been lost,
destroyed or wrongfully taken, then, in the absence of notice to the Company or
the Trustee that such Note has been acquired by a bona fide purchaser, the
Company shall issue and the Trustee shall authenticate a replacement Note of
like tenor and principal amount; provided that the requirements of this Section
2.09 are met. If required by the Trustee or the Company, an indemnity bond must

<PAGE>   36


                                       34

be furnished that is sufficient in the judgment of both the Trustee and the
Company to protect the Company, the Trustee or any Agent from any loss that any
of them may suffer if a Note is replaced. The Company may charge such Holder for
the expenses of the Company and the Trustee in replacing a Note. In case any
such mutilated, lost, destroyed or wrongfully taken Note has become or is about
to become due and payable, the Company in its discretion may pay such Note
instead of issuing a new Note in replacement thereof.

                  Every replacement Note is an additional obligation of the
Company and shall be entitled to the benefits of this Indenture.

                  The provisions of this Section 2.09 are exclusive and shall
preclude (to the extent lawful) all other rights and remedies against the
Company and the Trustee with respect to the replacement or payment of mutilated,
destroyed, lost or wrongfully taken Notes.

                  SECTION 2.10. Outstanding Notes. Notes outstanding at any time
are all Notes that have been authenticated by the Trustee except for those
cancelled by it, those delivered to it for cancellation and those described in
this Section 2.10 as not outstanding.

                  If a Note is replaced pursuant to Section 2.09, it ceases to
be outstanding unless and until the Trustee and the Company receive proof
satisfactory to each of them that the replaced Note is held by a bona fide
purchaser.

                  If the Paying Agent (other than the Company or an Affiliate of
the Company) holds on a Redemption Date or the Stated Maturity of the Notes
money sufficient to pay Notes payable on that date, then on and after that date
such Notes cease to be outstanding and interest on them shall cease to accrue.

                  Notes, or portions thereof, for the payment or redemption of
which moneys or U.S. Government Obligations (as provided for in Article Eight)
in the necessary amount shall have been deposited in trust with the Trustee or
with any Paying Agent (other than the Company) or shall have been set aside,
segregated and held in trust by the Company for the Holders of such Notes (if
the Company shall act as its own Paying Agent), on and after that time shall
cease to be outstanding and, in the case of redemption, interest on such Notes
shall cease to accrue, provided that if such Notes, or portions thereof, are to
be redeemed prior to the maturity thereof, notice of such redemption shall have
been given as herein provided, or provision satisfactory to the Trustee shall
have been made for giving such notice.

                  A Note does not cease to be outstanding because the Company or
one of its Affiliates holds such Note, provided, however, that, in determining
whether the Holders of the requisite principal amount of the outstanding Notes
have given any request, demand, authorization, direction, notice, consent or
waiver hereunder, Notes owned by the Company or any other obligor upon the Notes
or any Affiliate of the Company or of such other obligor

<PAGE>   37


                                       35

shall be disregarded and deemed not to be outstanding, except that, in
determining whether the Trustee shall be protected in relying upon any such
request, demand, authorization, direction, notice, consent or waiver, only Notes
which the Trustee has actual knowledge to be so owned shall be so disregarded.
Notes so owned which have been pledged in good faith may be regarded as
outstanding if the pledgee establishes to the satisfaction of the Trustee the
pledgee's right so to act with respect to such Notes and that the pledgee is not
the Company or any other obligor upon the Notes or any Affiliate of the Company
or of such other obligor.

                  SECTION 2.11. Temporary Notes. Until definitive Notes are
ready for delivery, the Company may prepare and execute and the Trustee shall
authenticate temporary Notes. Temporary Notes shall be substantially in the form
of definitive Notes but may have insertions, substitutions, omissions and other
variations determined to be appropriate by the Officers executing the temporary
Notes, as evidenced by their execution of such temporary Notes. If temporary
Notes are issued, the Company will cause definitive Notes to be prepared without
unreasonable delay. After the preparation of definitive Notes, the temporary
Notes shall be exchangeable for definitive Notes upon surrender of the temporary
Notes at the office or agency of the Company designated for such purpose
pursuant to Section 4.02, without charge to the Holder. Upon surrender for
cancellation of any one or more temporary Notes the Company shall execute and
the Trustee shall authenticate and deliver in exchange therefor a like principal
amount of definitive Notes of authorized denominations. Until so exchanged, the
temporary Notes shall be entitled to the same benefits under this Indenture as
definitive Notes.

                  SECTION 2.12. Cancellation. The Company at any time may
deliver, or cause to be delivered, Notes to the Trustee for cancellation. The
Registrar and the Paying Agent shall forward to the Trustee any Notes
surrendered to them for transfer, exchange or payment. The Trustee (and no one
else) shall cancel all Notes surrendered for transfer, exchange, payment,
replacement or cancellation and shall destroy them in accordance with its normal
procedure.

                  SECTION 2.13. CUSIP Numbers. The Company in issuing the Notes
may use "CUSIP," "CINS" and "ISIN" numbers (if then generally in use), and the
Trustee shall use CUSIP, CINS or ISIN numbers, as the case may be, in notices of
redemption or exchange as a convenience to Holders; provided that any such
notice shall state that no representation is made as to the correctness of such
CUSIP, CINS or ISIN numbers either as printed on the Notes or as contained in
any notice of redemption or exchange and that reliance may be placed only on the
other identification numbers printed on the Notes; and provided further that
failure to use CUSIP, CINS or ISIN numbers in any notice of redemption or
exchange shall not affect the validity or sufficiency of such notice. The
Company shall promptly notify the Trustee of any change in CUSIP numbers.

<PAGE>   38


                                       36

                  SECTION 2.14. Defaulted Interest. If the Company defaults in a
payment of interest on the Notes, it shall pay, or shall deposit with the Paying
Agent money in immediately available funds sufficient to pay the defaulted
interest, plus (to the extent lawful) any interest payable on the defaulted
interest, to the Persons who are Holders on a subsequent special record date. A
special record date, as used in this Section 2.14 with respect to the payment of
any defaulted interest, shall mean the 15th day next preceding the date fixed by
the Company for the payment of defaulted interest, whether or not such day is a
Business Day. At least 15 days before the subsequent special record date, the
Company shall mail to each Holder and to the Trustee a notice that states the
subsequent special record date, the payment date and the amount of defaulted
interest to be paid.

                  SECTION 2.15. Issuance of Additional Notes. The Company may,
subject to Article Four of this Indenture, issue additional Notes under this
Indenture. The Notes issued on the Closing Date and any additional Notes
subsequently issued shall be treated as a single class for all purposes under
this Indenture.


                                  ARTICLE THREE
                                   REDEMPTION

                  SECTION 3.01. Right of Redemption. (a) The Notes may be
redeemed at the election of the Company, in whole or in part, at any time and
from time to time on or after February 1, 2003 and prior to maturity, upon not
less than 30 nor more than 60 days' prior notice mailed by first-class mail to
each Holder's last address as it appears in the Note Register, at the following
Redemption Prices (expressed in percentages of their principal amount at
maturity), plus accrued and unpaid interest, if any, to the Redemption Date
(subject to the right of Holders of record on the relevant Regular Record Date
that is on or prior to the Redemption Date to receive interest due on an
Interest Payment Date) if redeemed during the 12-month period commencing
February 1, of the applicable years set forth below:

<TABLE>
<CAPTION>
                                                       Redemption
         Year                                             Price
         ----                                          ----------
         <S>                                           <C>
         2003                                           105.625%
         2004                                           103.750
         2005                                           101.875
         2006 and thereafter                            100.000
</TABLE>

                  (b) In addition, at any time prior to February 1, 2001, the
Company may redeem up to 35% of the principal amount of the Notes with the
proceeds of one or more sales of Capital Stock (other than Redeemable Stock), of
the Company, at any time or from time to time in part, at a Redemption Price
equal to 111.250% of their Accreted Value on

<PAGE>   39


                                       37

the Redemption Date provided that at least $280.8 million aggregate principal
amount at maturity of Notes remains outstanding after each of such redemption.

                  SECTION 3.02. Notices to Trustee. If the Company elects to
redeem Notes pursuant to Section 3.01(a) or 3.01(b), it shall notify the Trustee
in writing of the Redemption Date and the principal amount of Notes to be
redeemed.

                  The Company shall give each notice provided for in this
Section 3.02 in an Officers' Certificate at least 45 days before the Redemption
Date (unless a shorter period shall be satisfactory to the Trustee).

                  SECTION 3.03. Selection of Notes to Be Redeemed. If less than
all of the Notes are to be redeemed at any time, the Trustee shall select the
Notes to be redeemed in compliance with the requirements, as certified to it by
the Company, of the principal national securities exchange, if any, on which the
Notes are listed or, if the Notes are not listed on a national securities
exchange, by lot or by such other method as the Trustee in its sole discretion
shall deem fair and appropriate; provided that no Notes of $1,000 in principal
amount at maturity or less shall be redeemed in part.

                  The Trustee shall make the selection from the Notes
outstanding and not previously called for redemption. Notes in denominations of
$1,000 in principal amount at maturity may only be redeemed in whole. The
Trustee may select for redemption portions (equal to $1,000 in principal amount
at maturity or any integral multiple thereof) of Notes that have denominations
larger than $1,000 in principal amount at maturity. Provisions of this Indenture
that apply to Notes called for redemption also apply to portions of Notes called
for redemption. The Trustee shall notify the Company and the Registrar promptly
in writing of the Notes or portions of Notes to be called for redemption.

                  SECTION 3.04. Notice of Redemption. At least 30 days but not
more than 60 days before a Redemption Date, the Company shall mail a notice of
redemption by first class mail to each Holder whose Notes are to be redeemed.

                  The notice shall identify the Notes to be redeemed and shall
state:

                  (i)      the Redemption Date;

                  (ii)     the Redemption Price;

                  (iii)    the name and address of the Paying Agent;

                  (iv)     that Notes called for redemption must be surrendered
         to the Paying Agent in order to collect the Redemption Price;

<PAGE>   40


                                       38


                  (v) that, unless the Company defaults in making the redemption
         payment, interest on Notes called for redemption ceases to accrue on
         and after the Redemption Date and the only remaining right of the
         Holders is to receive payment of the Redemption Price plus accrued
         interest to the Redemption Date upon surrender of the Notes to the
         Paying Agent;

                  (vi) that, if any Note is being redeemed in part, the portion
         of the principal amount (equal to $1,000 in principal amount at
         maturity or any integral multiple thereof) of such Note to be redeemed
         and that, on and after the Redemption Date, upon surrender of such
         Note, a new Note or Notes in principal amount equal to the unredeemed
         portion thereof will be reissued; and

                  (vii) that, if any Note contains a CUSIP number as provided in
         Section 2.13, no representation is being made as to the correctness of
         the CUSIP number either as printed on the Notes or as contained in the
         notice of redemption and that reliance may be placed only on the other
         identification numbers printed on the Notes.

                  At the Company's request (which request may be revoked by the
Company at any time prior to the time at which the Trustee shall have given such
notice to the Holders), made in writing to the Trustee at least 60 days (or such
shorter period as shall be satisfactory to the Trustee) before a Redemption
Date, the Trustee shall give the notice of redemption in the name and at the
expense of the Company. If, however, the Company gives such notice to the
Holders, the Company shall concurrently deliver to the Trustee an Officers'
Certificate stating that such notice has been given.

                  SECTION 3.05. Effect of Notice of Redemption. Once notice of
redemption is mailed, Notes called for redemption become due and payable on the
Redemption Date and at the Redemption Price. Upon surrender of any Notes to the
Paying Agent, such Notes shall be paid at the Redemption Price, plus accrued
interest, if any, to the Redemption Date.

                  Notice of redemption shall be deemed to be given when mailed,
whether or not the Holder receives the notice. In any event, failure to give
such notice, or any defect therein, shall not affect the validity of the
proceedings for the redemption of Notes held by Holders to whom such notice was
properly given.

                  SECTION 3.06. Deposit of Redemption Price. On or prior to any
Redemption Date, the Company shall deposit with the Paying Agent (or, if the
Company is acting as its own Paying Agent, shall segregate and hold in trust as
provided in Section 2.05) money sufficient to pay the Redemption Price of and
accrued interest on all Notes to be redeemed on that date other than Notes or
portions thereof called for redemption on that date that have been delivered by
the Company to the Trustee for cancellation.

<PAGE>   41


                                       39

                  SECTION 3.07. Payment of Notes Called for Redemption. If
notice of redemption has been given in the manner provided above, the Notes or
portion of Notes specified in such notice to be redeemed shall become due and
payable on the Redemption Date at the Redemption Price stated therein, together
with accrued interest to such Redemption Date, and on and after such date
(unless the Company shall default in the payment of such Notes at the Redemption
Price and accrued interest to the Redemption Date, in which case the principal,
until paid, shall bear interest from the Redemption Date at the rate prescribed
in the Notes), such Notes shall cease to accrue interest. Upon surrender of any
Note for redemption in accordance with a notice of redemption, such Note shall
be paid and redeemed by the Company at the Redemption Price, together with
accrued interest, if any, to the Redemption Date; provided that installments of
interest whose Stated Maturity is on or prior to the Redemption Date shall be
payable to the Holders registered as such at the close of business on the
relevant Regular Record Date.

                  SECTION 3.08. Notes Redeemed in Part. Upon surrender of any
Note that is redeemed in part, the Company shall execute and the Trustee shall
authenticate and deliver to the Holder a new Note equal in principal amount to
the unredeemed portion of such surrendered Note.


                                  ARTICLE FOUR
                                    COVENANTS

                  SECTION 4.01. Payment of Notes. The Company shall pay the
principal of, premium, if any, and interest on the Notes on the dates and in the
manner provided in the Notes and this Indenture. An installment of principal,
premium, if any, or interest shall be considered paid on the date due if the
Trustee or Paying Agent (other than the Company, a Subsidiary of the Company, or
any Affiliate of any of them) holds on that date money designated for and
sufficient to pay the installment. If the Company or any Subsidiary of the
Company or any Affiliate of any of them, acts as Paying Agent, an installment of
principal, premium, if any, or interest shall be considered paid on the due date
if the entity acting as Paying Agent complies with the last sentence of Section
2.05. As provided in Section 6.09, upon any bankruptcy or reorganization
procedure relative to the Company, the Trustee shall serve as the Paying Agent
and conversion agent, if any, for the Notes.

                  The Company shall pay interest on overdue principal, premium,
if any, and interest on overdue installments of interest, to the extent lawful,
at the rate per annum specified in the Notes.

                  SECTION 4.02.  Maintenance of Office or Agency.  The Company
will maintain in the Borough of Manhattan, the City of New York an office or
agency where Notes may be surrendered for registration of transfer or exchange
or for presentation for

<PAGE>   42


                                       40

payment and where notices and demands to or upon the Company in respect of the
Notes and this Indenture may be served. The Company will give prompt written
notice to the Trustee of the location, and any change in the location, of such
office or agency. If at any time the Company shall fail to maintain any such
required office or agency or shall fail to furnish the Trustee with the address
thereof, such presentations, surrenders, notices and demands may be made or
served at the address of the Trustee set forth in Section 11.02.

                  The Company may also from time to time designate one or more
other offices or agencies where the Notes may be presented or surrendered for
any or all such purposes and may from time to time rescind such designations;
provided that no such designation or rescission shall in any manner relieve the
Company of its obligation to maintain an office or agency in the Borough of
Manhattan, the City of New York for such purposes. The Company will give prompt
written notice to the Trustee of any such designation or rescission and of any
change in the location of any such other office or agency.

                  The Company hereby initially designates the Corporate Trust
Office of the Trustee, located in the Borough of Manhattan, the City of New
York, as such office of the Company in accordance with Section 2.04.

                  SECTION 4.03. Limitation on Indebtedness. (a) The Company
will not, and will not permit any of its Restricted Subsidiaries to, Incur any
Indebtedness (other than the Notes and Indebtedness existing on the Closing
Date); provided that the Company may Incur Indebtedness if, after giving effect
to the Incurrence of such Indebtedness and the receipt and application of the
proceeds therefrom, the Consolidated Leverage Ratio would be greater than zero
and less than (x) 7:1, for Indebtedness Incurred on or prior to December 31,
2000 or (y) 6:1, for Indebtedness Incurred thereafter.

                  Notwithstanding the foregoing, the Company and any Restricted
Subsidiary (except as specified below) may Incur each and all of the following:

                  (i) Indebtedness of the Company outstanding at any time in an
         aggregate principal amount not to exceed the greater of (x) $150
         million and (y) an amount equal to 4.5 times the Company's Consolidated
         EBITDA for the then most recent four fiscal quarters for which
         financial statements of the Company have been filed with the Commission
         or provided to the Trustee pursuant to Section 4.18, in each case less
         any amount of such Indebtedness permanently repaid as provided under
         Section 4.11;

                  (ii) Indebtedness owed (A) to the Company evidenced by a
         promissory note or (B) to any Restricted Subsidiary; provided that any
         event which results in any such Restricted Subsidiary ceasing to be a
         Restricted Subsidiary or any subsequent transfer of such Indebtedness
         (other than to the Company or another Restricted Subsidiary)

<PAGE>   43


                                       41

         shall be deemed, in each case, to constitute an Incurrence of such
         Indebtedness not permitted by this clause (ii);

                  (iii) Indebtedness issued in exchange for, or the net proceeds
         of which are used to refinance or refund, then outstanding Indebtedness
         (other than Indebtedness Incurred under clause (i), (ii), (iv), (vii),
         (ix) or (xi) of this paragraph) and any refinancings thereof in an
         amount not to exceed the amount so refinanced or refunded (plus
         premiums, accrued interest, fees and expenses); provided that
         Indebtedness the proceeds of which are used to refinance or refund the
         Notes or Indebtedness that is pari passu with, or subordinated in right
         of payment to, the Notes shall only be permitted under this clause
         (iii) if (A) in case the Notes are refinanced in part or the
         Indebtedness to be refinanced is pari passu with the Notes, such new
         Indebtedness, by its terms or by the terms of any agreement or
         instrument pursuant to which such new Indebtedness is outstanding, is
         expressly made pari passu with, or subordinate in right of payment to,
         the remaining Notes, (B) in case the Indebtedness to be refinanced is
         subordinated in right of payment to the Notes, such new Indebtedness,
         by its terms or by the terms of any agreement or instrument pursuant to
         which such new Indebtedness is issued or remains outstanding, is
         expressly made subordinate in right of payment to the Notes at least to
         the extent that the Indebtedness to be refinanced is subordinated to
         the Notes and (C) such new Indebtedness, determined as of the date of
         Incurrence of such new Indebtedness, does not mature prior to the
         Stated Maturity of the Indebtedness to be refinanced or refunded, and
         the Average Life of such new Indebtedness is at least equal to the
         remaining Average Life of the Indebtedness to be refinanced or
         refunded; and provided further that in no event may Indebtedness of the
         Company be refinanced by means of any Indebtedness of any Restricted
         Subsidiary pursuant to this clause (iii);

                  (iv) Indebtedness (A) in respect of performance, surety or
         appeal bonds provided in the ordinary course of business, (B) under
         Currency Agreements and Interest Rate Agreements; provided that such
         agreements (a) are designed solely to protect the Company or its
         Restricted Subsidiaries against fluctuations in foreign currency
         exchange rates or interest rates and (b) do not increase the
         Indebtedness of the obligor outstanding at any time other than as a
         result of fluctuations in foreign currency exchange rates or interest
         rates or by reason of fees, indemnities and compensation payable
         thereunder and (C) arising from agreements providing for
         indemnification, adjustment of purchase price or similar obligations,
         or from Guarantees or letters of credit, surety bonds or performance
         bonds securing any obligations of the Company or any of its Restricted
         Subsidiaries pursuant to such agreements, in any case Incurred in
         connection with the disposition of any business, assets or Restricted
         Subsidiary (other than Guarantees of Indebtedness Incurred by any
         Person acquiring all or any portion of such business, assets or
         Restricted Subsidiary for the purpose of financing such acquisition),
         in a principal amount not to exceed the

<PAGE>   44


                                       42

         gross proceeds actually received by the Company or any Restricted
         Subsidiary in connection with such disposition;

                  (v) Indebtedness under letters of credit and bankers'
         acceptances issued in the ordinary course of business;

                  (vi) Acquired Indebtedness; provided that, with respect to
         this clause (vi), after giving effect to the Incurrence thereof, the
         Company's Consolidated Leverage Ratio is not more than it was
         immediately prior to the Incurrence of such Acquired Indebtedness;

                  (vii) Indebtedness, in an amount not to exceed $2 million at
         any one time outstanding, Incurred by the Company in connection with
         the purchase, redemption, acquisition, cancellation or other retirement
         for value of shares of Capital Stock of the Company or any Restricted
         Subsidiary, options on any such shares or related stock appreciation
         rights or similar securities held by officers or employees or former
         officers or employees (or their estates or beneficiaries under their
         estates), upon death, disability, retirement, termination of employment
         or pursuant to any agreement under which such shares of stock or
         related rights were issued; provided that (A) such Indebtedness, by its
         terms or by the terms of any agreement or instrument pursuant to which
         such Indebtedness is issued, is expressly made subordinate in right of
         payment to the Notes, (B) such Indebtedness, by its terms or by the
         terms of any agreement or instrument pursuant to which such
         Indebtedness is issued, provides that no payments of principal of such
         Indebtedness by way of sinking fund, mandatory redemption or otherwise
         (including defeasance) may be made by the Company at any time prior to
         the Stated Maturity of the Notes and (C) the scheduled maturity of all
         principal of such Indebtedness is beyond the Stated Maturity of the
         Notes;

                  (viii) Indebtedness of the Company to the extent the net
         proceeds thereof are promptly (A) used to purchase Notes tendered in an
         Offer to Purchase made as a result of a Change in Control or (B)
         deposited to defease the Notes in accordance with Section 8.01;

                  (ix) Guarantees of the Notes and Guarantees of Indebtedness of
         the Company by any Restricted Subsidiary provided the Guarantee of such
         Indebtedness is permitted by and made in accordance with Section 4.09;

                  (x) Indebtedness Incurred to finance the cost (including the
         cost of design, development, acquisition, construction, installation,
         improvement, transportation or integration) of equipment, inventory or
         network assets (including under any Capitalized Lease and the cost of
         the Capital Stock of a Person that becomes a Restricted Subsidiary to
         the extent of the fair market value of the equipment,

<PAGE>   45


                                       43

         inventory or network assets of such Person at the time it becomes a
         Restricted Subsidiary) to be acquired by the Company or a Restricted
         Subsidiary after the Closing Date;

                  (xi) Indebtedness of the Company not to exceed, at any time
         outstanding, two times the sum of (A) the Net Cash Proceeds received by
         the Company after the Closing Date from the issuance and sale of its
         Capital Stock (other than Redeemable Stock) to a Person that is not a
         Subsidiary of the Company, to the extent such Net Cash Proceeds have
         not been used pursuant to clause (C)(2) of the first paragraph or
         clause (iii), (iv) or (vi) of the second paragraph of Section 4.06 to
         make a Restricted Payment and (B) 80% of the fair market value of
         property (other than cash and cash equivalents) received by the Company
         after the Closing Date from the sale of its Capital Stock (other than
         Redeemable Stock) to a Person that is not a Subsidiary of the Company,
         to the extent such sale of Capital Stock has not been used pursuant to
         clause (iii), (iv) or (vii) of the second paragraph of Section 4.06 to
         make a Restricted Payment; provided that such Indebtedness does not
         mature prior to the Stated Maturity of the Notes and has an Average
         Life longer than the Notes; and

                  (xii) Guarantees of Indebtedness, in an aggregate principal
         amount not to exceed $10 million, of any Person the primary business of
         which is located outside the United States and is related, ancillary or
         complementary to the business of the Company and its Restricted
         Subsidiaries.

                  (b) Notwithstanding any other provision of this Section 4.03,
the maximum amount of Indebtedness that the Company or a Restricted Subsidiary
may Incur pursuant to this Section 4.03 shall not be deemed to be exceeded, with
respect to any outstanding Indebtedness due solely to the result of fluctuations
in the exchange rates of currencies.

                  (c) For purposes of determining any particular amount of
Indebtedness under this Section 4.03, (1) Guarantees, Liens or obligations with
respect to letters of credit supporting Indebtedness otherwise included in the
determination of such particular amount shall not be included and (2) any Liens
granted pursuant to the equal and ratable provisions referred to in Section 4.05
shall not be treated as Indebtedness. For purposes of determining compliance
with this Section 4.03, in the event that an item of Indebtedness meets the
criteria of more than one of the types of Indebtedness described in the above
clauses, the Company, in its sole discretion, shall classify such item of
Indebtedness and only be required to include the amount and type of such
Indebtedness in one of such clauses.

                  SECTION 4.04. Limitation on Senior Subordinated Indebtedness.
The Company shall not Incur any Indebtedness that is subordinate in right of
payment to any Senior Indebtedness unless such Indebtedness is pari passu with,
or subordinated in right of payment to, the Notes; provided that the foregoing
limitation shall not apply to distinctions

<PAGE>   46


                                       44

between categories of Senior Indebtedness of the Company that exist by reason of
any Liens or Guarantees arising or created in respect of some but not all such
Senior Indebtedness.

                  SECTION 4.05. Limitation on Liens. The Company shall not Incur
any Indebtedness secured by a Lien ("Secured Indebtedness") which is not Senior
Indebtedness unless contemporaneously therewith effective provision is made to
secure the Notes equally and ratably with (or, if the Secured Indebtedness is
subordinated in right of payment to the Notes, prior to) such Secured
Indebtedness for so long as such Secured Indebtedness is secured by a Lien.

                  SECTION 4.06. Limitation on Restricted Payments. The Company
will not, and will not permit any Restricted Subsidiary to, directly or
indirectly, (i) declare or pay any dividend or make any distribution on or with
respect to its Capital Stock (other than (x) dividends or distributions payable
solely in shares of its Capital Stock (other than Redeemable Stock) or in
options, warrants or other rights to acquire shares of such Capital Stock and
(y) pro rata dividends or distributions on Common Stock of Restricted
Subsidiaries held by minority stockholders) held by Persons other than the
Company or any of its Restricted Subsidiaries, (ii) purchase, redeem, retire or
otherwise acquire for value any shares of Capital Stock of (A) the Company or an
Unrestricted Subsidiary (including options, warrants or other rights to acquire
such shares of Capital Stock) held by any Person, or (B) a Restricted Subsidiary
(including options, warrants or other rights to acquire such shares of Capital
Stock) held by any Affiliate of the Company (other than a Wholly Owned
Restricted Subsidiary) or any holder (or any Affiliate of such holder) of 5% or
more of the Capital Stock of the Company, (iii) make any voluntary or optional
principal payment, or voluntary or optional redemption, repurchase, defeasance,
or other acquisition or retirement for value, of Indebtedness of the Company
that is subordinated in right of payment to the Notes, or (iv) make any
Investment, other than a Permitted Investment, in any Person (such payments or
any other actions described in clauses (i) through (iv) being collectively
"Restricted Payments") if, at the time of, and after giving effect to, the
proposed Restricted Payment: (A) a Default or Event of Default shall have
occurred and be continuing, (B) the Company could not Incur at least $1.00 of
Indebtedness under the first paragraph of Section 4.03(a) or (C) the aggregate
amount expended for all Restricted Payments (the amount, if other than in cash,
to be determined in good faith by the Board of Directors, whose determination
shall be conclusive and evidenced by a Board Resolution) made after the Closing
Date shall exceed the sum of (1) 50% of the aggregate amount of the Adjusted
Consolidated Net Income (or, if the Adjusted Consolidated Net Income is a loss,
minus 100% of the amount of such loss) (determined by excluding income resulting
from transfers of assets by the Company or a Restricted Subsidiary to an
Unrestricted Subsidiary) accrued on a cumulative basis during the period (taken
as one accounting period) beginning on the first day of the fiscal quarter
immediately following the Closing Date and ending on the last day of the last
fiscal quarter preceding the Transaction Date for which reports have been filed
with the Commission or provided to the Trustee pursuant to Section 4.18 plus (2)
the aggregate Net Cash Proceeds

<PAGE>   47


                                       45

received by the Company after the Closing Date from the issuance and sale
permitted by this Indenture of its Capital Stock (other than Redeemable Stock)
to a Person who is not a Subsidiary of the Company, including an issuance or
sale permitted by this Indenture of Indebtedness of the Company for cash
subsequent to the Closing Date, upon the conversion of such Indebtedness into
Capital Stock (other than Redeemable Stock) of the Company, or from the issuance
to a Person who is not a Subsidiary of the Company of any options, warrants or
other rights to acquire Capital Stock of the Company (in each case, exclusive of
any Redeemable Stock or any options, warrants or other rights that are
redeemable at the option of the holder, or are required to be redeemed, prior to
the Stated Maturity of the Notes), in each case except to the extent such Net
Cash Proceeds are used to Incur Indebtedness pursuant to clause (xi) of the
second paragraph of Section 4.03 plus (3) an amount equal to the net reduction
in Investments (other than reductions in Permitted Investments) in any Person
resulting from payments of interest on Indebtedness, dividends, repayments of
loans or advances, or other transfers of assets, in each case to the Company or
any Restricted Subsidiary or from the Net Cash Proceeds from the sale of any
such Investment (except, in each case, to the extent any such payment or
proceeds are included in the calculation of Adjusted Consolidated Net Income),
or from redesignations of Unrestricted Subsidiaries as Restricted Subsidiaries
(valued in each case as provided in the definition of "Investments"), not to
exceed, in each case, the amount of Investments previously made by the Company
or any Restricted Subsidiary in such Person or Unrestricted Subsidiary.

                  The foregoing provision shall not be violated by reason of:

                  (i) the payment of any dividend within 60 days after the date
         of declaration thereof if, at said date of declaration, such payment
         would comply with the foregoing paragraph;

                  (ii) the redemption, repurchase, defeasance or other
         acquisition or retirement for value of Indebtedness that is
         subordinated in right of payment to the Notes including premium, if
         any, and accrued and unpaid interest, with the proceeds of, or in
         exchange for, Indebtedness Incurred under clause (iii) of the second
         paragraph of Section 4.03(a);

                  (iii) the repurchase, redemption or other acquisition of
         Capital Stock of the Company or an Unrestricted Subsidiary (or options,
         warrants or other rights to acquire said Capital Stock) in exchange
         for, or out of the proceeds of a substantially concurrent offering of,
         shares of Capital Stock (other than Redeemable Stock) of the Company
         (or options, warrants or other rights to acquire such Capital Stock);

                  (iv) the making of any principal payment or the repurchase,
         redemption, retirement, defeasance or other acquisition for value of
         Indebtedness of the Company which is subordinated in right of payment
         to the Notes in exchange for, or out of the

<PAGE>   48


                                       46

         proceeds of, a substantially concurrent offering of, shares of the
         Capital Stock (other than Redeemable Stock) of the Company (or options,
         warrants or other rights to acquire such Capital Stock);

                  (v) payments or distributions, to dissenting stockholders
         pursuant to applicable law, pursuant to or in connection with a
         consolidation, merger or transfer of assets that complies with the
         provisions of this Indenture applicable to mergers, consolidations and
         transfers of all or substantially all of the property and assets of the
         Company;

                  (vi) Investments in any Person the primary business of which
         is related, ancillary or complementary to the business of the Company
         and its Restricted Subsidiaries on the date of such Investments;
         provided that the aggregate amount of Investments made pursuant to this
         clause (vi) does not exceed the sum of (x) $15 million plus (y) the
         amount of Net Cash Proceeds received by the Company after the Closing
         Date from the sale of its Capital Stock (other than Redeemable Stock)
         to a Person who is not a Subsidiary of the Company, except to the
         extent such Net Cash Proceeds are used to Incur Indebtedness pursuant
         to clause (xi) of Section 4.03 or to make Restricted Payments pursuant
         to clause (C)(2) of the first paragraph, or clauses (iii) or (iv) of
         this paragraph, of this Section 4.06, plus (z) the net reduction in
         Investments made pursuant to this clause (vi) resulting from
         distributions on or repayments of such Investments or from the Net Cash
         Proceeds from the sale of any such Investment (except in each case to
         the extent any such payment or proceeds is included in the calculation
         of Adjusted Consolidated Net Income) or from such Person becoming a
         Restricted Subsidiary (valued in each case as provided in the
         definition of "Investments"), provided that the net reduction in any
         Investment shall not exceed the amount of such Investment;

                  (vii) Investments acquired in exchange for Capital Stock
         (other than Redeemable Stock) of the Company;

                  (viii) the declaration or payment of dividends on the Common
         Stock of the Company following a Public Equity Offering of such Common
         Stock, of up to 6% per annum of the Net Cash Proceeds received by the
         Company in such Public Equity Offering;

                  (ix) repurchases of Warrants pursuant to a Repurchase Offer
         (as defined in the Warrant Agreement);

                  (x) any purchase of any fractional share of Common Stock of
         the Company in connection with an exercise of the Warrants;

<PAGE>   49


                                       47

                  (xi) the purchase, redemption, acquisition, cancellation or
         other retirement for value of shares of Capital Stock of the Company or
         any Restricted Subsidiary, options on any such shares or related stock
         appreciation rights or similar securities held by officers or employees
         or former officers or employees (or their estates or beneficiaries
         under their estates), upon death, disability, retirement, termination
         of employment or pursuant to any agreement under which such shares of
         stock or related rights were issued; provided that the aggregate cash
         consideration paid for such purchase, redemption, acquisition,
         cancellation or other retirement of such shares of Capital Stock or
         related rights after the Closing Date does not exceed an aggregate
         amount of $5 million;

                  (xii) the purchase, redemption, acquisition, cancellation or
         other retirement for value of shares of Capital Stock of the Company or
         any Restricted Subsidiary to the extent necessary, in the judgment of
         the Board of Directors, to prevent the loss or secure the renewal or
         reinstatement of any license or franchise held by the Company or any of
         its Restricted Subsidiaries from any governmental agency;

                  (xiii) Investments in any Person the primary business of which
         is located outside the United States and is related, ancillary or
         complementary to the business of the Company and its Restricted
         Subsidiaries on the date of such Investments, provided that the
         aggregate amount of Investments pursuant to this clause (xiii) does not
         exceed (x) $10 million plus (y) the net reduction in Investments made
         pursuant to this clause (xiii) resulting from distributions on or
         repayments of such Investments or from the Net Cash Proceeds from the
         sale of any such Investment (except in each case to the extent any such
         payment or proceeds is included in the calculation of Adjusted
         Consolidated Net Income) or from such Person becoming a Restricted
         Subsidiary (valued in each case as provided in the definition of
         "Investments"), provided that the net reduction in any Investment shall
         not exceed the amount of such Investment; or

                  (xiv) Investments in the form of Guarantees Incurred under
         Section 4.03(a)(xii);

provided that, except in the case of clauses (i) and (iii), no Default or Event
of Default shall have occurred and be continuing or occur as a consequence of
the actions or payments set forth therein.

                  Each Restricted Payment permitted pursuant to this Section
4.06 (other than the Restricted Payment referred to in clause (ii), an exchange
of Capital Stock for Capital Stock or Indebtedness referred to in clause (iii)
or (iv) and an Investment referred to in clause (vi) or (vii)), and the Net Cash
Proceeds from any issuance of Capital Stock referred to in clauses (iii) and
(iv), shall be included in calculating whether the conditions of clause (C) of
the first paragraph of this Section 4.06 have been met with respect to any

<PAGE>   50


                                       48

subsequent Restricted Payments. In the event the proceeds of an issuance of
Capital Stock of the Company are used for the redemption, repurchase or other
acquisition of the Notes, or Indebtedness that is pari passu with the Notes,
then the Net Cash Proceeds of such issuance shall be included in clause (C) of
the first paragraph of this Section 4.06 only to the extent such proceeds are
not used for such redemption, repurchase or other acquisition of Indebtedness.

                  SECTION 4.07. Limitation on Dividend and Other Payment
Restrictions Affecting Restricted Subsidiaries. The Company will not, and will
not permit any Restricted Subsidiary to, create or otherwise cause or suffer to
exist or become effective any consensual encumbrance or restriction of any kind
on the ability of any Restricted Subsidiary to (i) pay dividends or make any
other distributions permitted by applicable law on any Capital Stock of such
Restricted Subsidiary owned by the Company or any other Restricted Subsidiary,
(ii) pay any Indebtedness owed to the Company or any other Restricted
Subsidiary, (iii) make loans or advances to the Company or any other Restricted
Subsidiary or (iv) transfer any of its property or assets to the Company or any
other Restricted Subsidiary.

                  The foregoing provisions shall not restrict any encumbrances
or restrictions:

                  (i) existing on the Closing Date in the Credit Agreement, the
         Vendor Financing Arrangement, the 15% Indenture, this Indenture or any
         other agreements in effect on the Closing Date, and any extensions,
         refinancings, renewals or replacements of such agreements; provided
         that the encumbrances and restrictions in any such extensions,
         refinancings, renewals or replacements are no less favorable in any
         material respect to the Holders than those encumbrances or restrictions
         that are then in effect and that are being extended, refinanced,
         renewed or replaced;

                  (ii) existing under or by reason of applicable law;

                  (iii) existing with respect to any Person or the property or
         assets of such Person acquired by the Company or any Restricted
         Subsidiary, existing at the time of such acquisition and not incurred
         in contemplation thereof, which encumbrances or restrictions are not
         applicable to any Person or the property or assets of any Person other
         than such Person or the property or assets of such Person so acquired;

                  (iv) in the case of clause (iv) of the first paragraph of this
         Section 4.07, (A) that restrict in a customary manner the subletting,
         assignment or transfer of any property or asset that is a lease,
         license, conveyance or contract or similar property or asset, (B)
         existing by virtue of any transfer of, agreement to transfer, option or
         right with respect to, or Lien on, any property or assets of the
         Company or any Restricted Subsidiary not otherwise prohibited by this
         Indenture or (C) arising or agreed to in the ordinary course of
         business, not relating to any Indebtedness, and that do not,

<PAGE>   51


                                       49

         individually or in the aggregate, detract from the value of property or
         assets of the Company or any Restricted Subsidiary in any manner
         material to the Company or any Restricted Subsidiary;

                  (v) with respect to a Restricted Subsidiary and imposed
         pursuant to an agreement that has been entered into for the sale or
         disposition of all or substantially all of the Capital Stock of, or
         property and assets of, such Restricted Subsidiary; or

                  (vi) contained in the terms of any Indebtedness or any
         agreement pursuant to which such Indebtedness was issued if (A) the
         encumbrance or restriction applies only in the event of a payment
         default or a default with respect to a financial covenant contained in
         such Indebtedness or agreement, (B) the encumbrance or restriction is
         not materially more disadvantageous to the Holders of the Notes than is
         customary in comparable financings (as determined by the Company) and
         (C) the Company determines that any such encumbrance or restriction
         will not materially affect the Company's ability to make principal or
         interest payments on the Notes.

Nothing contained in this Section 4.07 shall prevent the Company or any
Restricted Subsidiary from (1) creating, incurring, assuming or suffering to
exist any Liens otherwise permitted in Section 4.05 or (2) restricting the sale
or other disposition of property or assets of the Company or any of its
Restricted Subsidiaries that secure Indebtedness of the Company or any of its
Restricted Subsidiaries.

                  SECTION 4.08. Limitation on the Issuance and Sale of Capital
Stock of Restricted Subsidiaries. The Company will not sell, and will not permit
any Restricted Subsidiary, directly or indirectly, to issue or sell, any shares
of Capital Stock of a Restricted Subsidiary (including options, warrants or
other rights to purchase shares of such Capital Stock) except (i) to the Company
or a Wholly Owned Restricted Subsidiary; (ii) issuances of director's qualifying
shares or sales to foreign nationals of shares of Capital Stock of foreign
Restricted Subsidiaries, to the extent required by applicable law; (iii) if,
immediately after giving effect to such issuance or sale, such Restricted
Subsidiary would no longer constitute a Restricted Subsidiary and any Investment
in such Person remaining after giving effect to such issuance or sale would have
been permitted to be made under Section 4.06 if made on the date of such
issuance or sale; or (iv) issuances and sales of Common Stock, if the Net Cash
Proceeds from such issuance or sale are applied, to the extent required to be
applied, pursuant to Section 4.11.

                  SECTION 4.09. Limitation on Issuances of Guarantees by
Restricted Subsidiaries. The Company will not permit any Restricted Subsidiary,
directly or indirectly, to Guarantee any Indebtedness of the Company which is
pari passu with or subordinate in right of payment to the Notes ("Guaranteed
Indebtedness"), unless (i) such Restricted Subsidiary simultaneously executes
and delivers a supplemental indenture to this Indenture

<PAGE>   52


                                       50

providing for a Guarantee (a "Subsidiary Guarantee") of payment of the Notes by
such Restricted Subsidiary and (ii) such Restricted Subsidiary waives and will
not in any manner whatsoever claim or take the benefit or advantage of, any
rights of reimbursement, indemnity or subrogation or any other rights against
the Company or any other Restricted Subsidiary as a result of any payment by
such Restricted Subsidiary under its Subsidiary Guarantee; provided that this
paragraph shall not be applicable to any Guarantee of any Restricted Subsidiary
that existed at the time such Person became a Restricted Subsidiary and was not
Incurred in connection with, or in contemplation of, such Person becoming a
Restricted Subsidiary. If the Guaranteed Indebtedness is (A) pari passu with the
Notes, then the Guarantee of such Guaranteed Indebtedness shall be pari passu
with, or subordinated to, the Subsidiary Guarantee or (B) subordinated to the
Notes, then the Guarantee of such Guaranteed Indebtedness shall be subordinated
to the Subsidiary Guarantee at least to the extent that the Guaranteed
Indebtedness is subordinated to the Notes.

                  Notwithstanding the foregoing, any Subsidiary Guarantee by a
Restricted Subsidiary may provide by its terms that it shall be automatically
and unconditionally released and discharged upon (i) any sale, exchange or
transfer, to any Person not an Affiliate of the Company, of all of the Company's
and each Restricted Subsidiary's Capital Stock in, or all or substantially all
the assets of, such Restricted Subsidiary (which sale, exchange or transfer is
not prohibited by the Indenture) or (ii) the release or discharge of the
Guarantee which resulted in the creation of such Subsidiary Guarantee, except a
discharge or release by or as a result of payment under such Guarantee.

                  SECTION 4.10. Limitation on Transactions with Shareholders and
Affiliates. The Company will not, and will not permit any Restricted Subsidiary
to, directly or indirectly, enter into, renew or extend any transaction
(including, without limitation, the purchase, sale, lease or exchange of
property or assets, or the rendering of any service) with any holder (or any
Affiliate of such holder) of 5% or more of any class of Capital Stock of the
Company or with any Affiliate of the Company or any Restricted Subsidiary,
except upon fair and reasonable terms no less favorable to the Company or such
Restricted Subsidiary than could be obtained, at the time of such transaction
or, if such transaction is pursuant to a written agreement, at the time of the
execution of the agreement providing therefor, in a comparable arm's-length
transaction with a Person that is not such a holder or an Affiliate.

                  The foregoing limitation does not limit, and shall not apply
to:

                  (i) transactions (A) approved by a majority of the
         disinterested members of the Board of Directors or (B) for which the
         Company or a Restricted Subsidiary delivers to the Trustee a written
         opinion of a nationally recognized investment banking firm stating that
         the transaction is fair to the Company or such Restricted Subsidiary
         from a financial point of view;


<PAGE>   53


                                       51

                  (ii) any transaction solely between the Company and any of its
         Wholly Owned Restricted Subsidiaries or solely between Wholly Owned
         Restricted
         Subsidiaries;

                  (iii) the payment of reasonable and customary regular fees to
         directors of the Company who are not employees of the Company;

                  (iv) any payments or other transactions pursuant to any
         tax-sharing agreement between the Company and any other Person with
         which the Company files a consolidated tax return or with which the
         Company is part of a consolidated group for tax purposes;

                  (v) the payment of amounts to Morgan Stanley & Co.
         Incorporated or its Affiliates pursuant to underwriting or placement
         agreements;

                  (vi) any loans or advances to officers or employees of the
         Company or any Restricted Subsidiary in the ordinary course of
         business;

                  (vii) any Restricted Payments not prohibited by Section 4.06
         (including any Permitted Investment);

                  (viii) the sale, lease, transfer or other disposition by the
         Company or any Restricted Subsidiary of Capital Stock or assets of any
         Unrestricted Subsidiary having a fair market value of less than $5
         million as determined by the Board of Directors; and

                  (ix) any transactions solely between shareholders of the
         Company (including amendments to any shareholder agreement to which the
         Company is a party); provided that the Company is not affected in any
         material way by any such transaction.

                  SECTION 4.11. Limitation on Asset Sales. The Company will not,
and will not permit any Restricted Subsidiary to, consummate any Asset Sale,
unless (i) the consideration received by the Company or such Restricted
Subsidiary is at least equal to the fair market value of the assets sold or
disposed of and (ii) at least 75% of the consideration received consists of cash
or Temporary Cash Investments or the assumption of Indebtedness of the Company
or such Restricted Subsidiary provided that the Company and its Restricted
Subsidiaries are irrevocably released from all liability with respect to such
Indebtedness. In the event and to the extent that the Net Cash Proceeds received
by the Company or any of its Restricted Subsidiaries from one or more Asset
Sales occurring on or after the Closing Date in any period of 12 consecutive
months exceed 10% of Adjusted Consolidated Net Tangible Assets (determined as of
the date closest to the commencement of such 12-month period for

<PAGE>   54


                                       52

which a consolidated balance sheet of the Company and its Subsidiaries has been
filed with the Commission pursuant to Section 4.18), then the Company shall or
shall cause the relevant Restricted Subsidiary to (x) within 12 months after the
date Net Cash Proceeds so received exceed 10% of Adjusted Consolidated Net
Tangible Assets (A) apply an amount equal to such excess Net Cash Proceeds to
permanently repay Senior Indebtedness of the Company, or any Restricted
Subsidiary providing a Subsidiary Guarantee pursuant to Section 4.09 or
Indebtedness of any other Restricted Subsidiary, in each case owing to a Person
other than the Company or any of its Restricted Subsidiaries or (B) invest an
equal amount, or the amount not so applied pursuant to clause (A) (or enter into
a definitive agreement committing to so invest within 12 months after the date
of such agreement), in property or assets (other than current assets) of a
nature or type or that are used in a business (or in a company having property
and assets of a nature or type, or engaged in a business) similar or related to
the nature or type of the property and assets of, or the business of, the
Company and its Restricted Subsidiaries existing on the date of such investment
(as determined in good faith by the Board of Directors, whose determination
shall be conclusive and evidenced by a Board Resolution) and (y) apply (no later
than the end of the 12-month period referred to in clause (x)) such excess Net
Cash Proceeds (to the extent not applied pursuant to clause (x)) as provided in
the following paragraphs of this Section 4.11. The amount of such excess Net
Cash Proceeds required to be applied (or to be committed to be applied) during
such 12- month period as set forth in clause (x) of the preceding sentence and
not applied as so required by the end of such period shall constitute "Excess
Proceeds".

                  If, as of the first day of any calendar month, the aggregate
amount of Excess Proceeds not theretofore subject to an Offer to Purchase
pursuant to this Section 4.11 totals at least $10 million, the Company must
commence, not later than the fifteenth Business Day of such month, and
consummate an Offer to Purchase from the Holders on a pro rata basis an
aggregate Accreted Value of Notes equal to the Excess Proceeds on such date, at
a purchase price equal to 100% of the Accreted Value of the Notes on the
relevant Payment Date, plus, in each case, accrued interest (if any) to the
Payment Date.

                  SECTION 4.12. Repurchase of Notes upon a Change of Control.
The Company shall commence, within 30 days of the occurrence of a Change of
Control, and consummate an Offer to Purchase for all Notes then outstanding, at
a purchase price equal to 101% of the Accreted Value thereof on the relevant
Payment Date, plus accrued interest (if any) to the Payment Date.

                  SECTION 4.13. Existence. Subject to Articles Four and Five of
this Indenture, the Company will do or cause to be done all things necessary to
preserve and keep in full force and effect its existence and the existence of
each of its Restricted Subsidiaries in accordance with the respective
organizational documents of the Company and each such Subsidiary and the rights
(whether pursuant to charter, partnership certificate, agreement, statute or
otherwise), material licenses and franchises of the Company and each such

<PAGE>   55


                                       53

Subsidiary; provided that the Company shall not be required to preserve any such
right, license or franchise, or the existence of any Restricted Subsidiary, if
the maintenance or preservation thereof is no longer desirable in the conduct of
the business of the Company and Restricted its Subsidiaries taken as a whole.

                  SECTION 4.14. Payment of Taxes and Other Claims. The Company
will pay or discharge and shall cause each of its Subsidiaries to pay or
discharge, or cause to be paid or discharged, before the same shall become
delinquent (i) all material taxes, assessments and governmental charges levied
or imposed upon (a) the Company or any such Subsidiary, (b) the income or
profits of any such Subsidiary which is a corporation or (c) the property of the
Company or any such Subsidiary and (ii) all material lawful claims for labor,
materials and supplies that, if unpaid, might by law become a lien upon the
property of the Company or any such Subsidiary; provided that the Company shall
not be required to pay or discharge, or cause to be paid or discharged, any such
tax, assessment, charge or claim the amount, applicability or validity of which
is being contested in good faith by appropriate proceedings and for which
adequate reserves have been established.

                  SECTION 4.15. Maintenance of Properties and Insurance. The
Company will cause all properties used or useful in the conduct of its business
or the business of any of its Restricted Subsidiaries, to be maintained and kept
in good condition, repair and working order and supplied with all necessary
equipment and will cause to be made all necessary repairs, renewals,
replacements, betterments and improvements thereof, all as in the judgment of
the Company may be necessary so that the business carried on in connection
therewith may be properly and advantageously conducted at all times; provided
that nothing in this Section 4.15 shall prevent the Company or any such
Subsidiary from discontinuing the use, operation or maintenance of any of such
properties or disposing of any of them, if such discontinuance or disposal is,
in the judgment of the Company, desirable in the conduct of the business of the
Company or such Subsidiary.

                  The Company will provide or cause to be provided, for itself
and its Restricted Subsidiaries, insurance (including appropriate
self-insurance) against loss or damage of the kinds customarily insured against
by corporations similarly situated and owning like properties, including, but
not limited to, products liability insurance and public liability insurance,
with reputable insurers or with the government of the United States of America,
or an agency or instrumentality thereof, in such amounts, with such deductibles
and by such methods as shall be customary for corporations similarly situated in
the industry in which the Company or such Restricted Subsidiary, as the case may
be, is then conducting business.

                  SECTION 4.16. Notice of Defaults. In the event that the
Company becomes aware of any Default or Event of Default the Company, promptly
after it becomes aware thereof, will give written notice thereof to the Trustee.

<PAGE>   56


                                       54

                  SECTION 4.17. Compliance Certificates. (a) The Company shall
deliver to the Trustee, within 45 days after the end of each fiscal quarter (90
days after the end of the last fiscal quarter of each year), an Officers'
Certificate stating whether or not the signers know of any Default or Event of
Default that occurred during such fiscal quarter. In the case of the Officers'
Certificate delivered within 90 days of the end of the Company's fiscal year,
such certificate shall contain a certification from the principal executive
officer, principal financial officer or principal accounting officer that a
review has been conducted of the activities of the Company and its Restricted
Subsidiaries and the Company's and its Restricted Subsidiaries' performance
under this Indenture and that the Company has complied with all conditions and
covenants under this Indenture. For purposes of this Section 4.17, such
compliance shall be determined without regard to any period of grace or
requirement of notice provided under this Indenture. If they do know of such a
Default or Event of Default, the certificate shall describe any such Default or
Event of Default and its status. The first certificate to be delivered pursuant
to this Section 4.17(a) shall be for the first fiscal quarter beginning after
the execution of this Indenture.

                  (b) The Company shall deliver to the Trustee, within 90 days
after the end of the Company's fiscal year, a certificate signed by the
Company's independent certified public accountants stating (i) that their audit
examination has included a review of the terms of this Indenture and the Notes
as they relate to accounting matters, (ii) that they have read the most recent
Officers' Certificate delivered to the Trustee pursuant to paragraph (a) of this
Section 4.17 and (iii) whether, in connection with their audit examination,
anything came to their attention that caused them to believe that the Company
was not in compliance with any of the terms, covenants, provisions or conditions
of Article Four and Section 5.01 of this Indenture as they pertain to accounting
matters and, if any Default or Event of Default has come to their attention,
specifying the nature and period of existence thereof; provided that such
independent certified public accountants shall not be liable in respect of such
statement by reason of any failure to obtain knowledge of any such Default or
Event of Default that would not be disclosed in the course of an audit
examination conducted in accordance with generally accepted auditing standards
in effect at the date of such examination.

                  (c) Within 90 days of the end of each of the Company's fiscal
years, the Company shall deliver to the Trustee a list of all Significant
Subsidiaries. The Trustee shall have no duty with respect to any such list
except to keep it on file and available for inspection by the Holders.

                  SECTION 4.18. Commission Reports and Reports to Holders.
Whether or not the Company is then required to file reports with the Commission,
the Company shall file with the Commission all such reports and other
information as it would be required to file with the Commission by Sections
13(a) or 15(d) under the Exchange Act if it were subject thereto. The Company
shall supply the Trustee and each Holder, or shall supply to

<PAGE>   57


                                       55

the Trustee for forwarding to each such Holder, without cost to such Holder,
copies of such reports or other information.

                  SECTION 4.19. Waiver of Stay, Extension or Usury Laws. The
Company covenants (to the extent that it may lawfully do so) that it will not at
any time insist upon, or plead, or in any manner whatsoever claim or take the
benefit or advantage of, any stay or extension law or any usury law or other law
that would prohibit or forgive the Company from paying all or any portion of the
principal of, premium, if any, or interest on the Notes as contemplated herein,
wherever enacted, now or at any time hereafter in force, or that may affect the
covenants or the performance of this Indenture; and (to the extent that it may
lawfully do so) the Company hereby expressly waives all benefit or advantage of
any such law and covenants that it will not hinder, delay or impede the
execution of any power herein granted to the Trustee, but will suffer and permit
the execution of every such power as though no such law had been enacted.


                                  ARTICLE FIVE
                              SUCCESSOR CORPORATION

                  SECTION 5.01. When Company May Merge, Etc. The Company shall
not consolidate with, merge with or into, or sell, convey, transfer, lease or
otherwise dispose of all or substantially all of its property and assets (as an
entirety or substantially an entirety in one transaction or a series of related
transactions) to, any Person or permit any Person to merge with or into the
Company unless:

                  (i) the Company shall be the continuing Person, or the Person
         (if other than the Company) formed by such consolidation or into which
         the Company is merged or that acquired or leased such property and
         assets of the Company shall be a corporation organized and validly
         existing under the laws of the United States of America or any
         jurisdiction thereof and shall expressly assume, by a supplemental
         indenture, executed and delivered to the Trustee, all of the
         obligations of the Company on all of the Notes and under the Indenture;

                  (ii) immediately after giving effect to such transaction, no
         Default or Event of Default shall have occurred and be continuing;

                  (iii) immediately after giving effect to such transaction on a
         pro forma basis, (A) the Company or any Person becoming the successor
         obligor of the Notes, as the case may be, shall have a Consolidated Net
         Worth equal to or greater than the Consolidated Net Worth of the
         Company immediately prior to such transaction, or (B) the Company or
         any Person becoming the successor obligor of the Notes, as the case may
         be, shall have a Consolidated Leverage Ratio no more than the greater
         of (I)

<PAGE>   58


                                       56

         7:1, on or prior to December 31, 2000, or 6:1 thereafter and (II) the
         Consolidated Leverage Ratio of the Company immediately prior to such
         transaction; provided that this clause (iii) shall not apply to a
         consolidation or merger with or into a Wholly Owned Restricted
         Subsidiary with a positive net worth; provided that, in connection with
         any such merger or consolidation, no consideration (other than Capital
         Stock (other than Redeemable Stock) in the surviving Person or the
         Company) shall be issued or distributed to the stockholders of the
         Company; and

                  (iv) the Company delivers to the Trustee an Officers'
         Certificate (attaching the arithmetic computations to demonstrate
         compliance with clause (iii)) and Opinion of Counsel, in each case
         stating that such consolidation, merger or transfer and such
         supplemental indenture complies with this provision and that all
         conditions precedent provided for herein relating to such transaction
         have been complied with;

provided, however, that clause (iii) above does not apply if, in the good faith
determination of the Board of Directors of the Company, whose determination
shall be evidenced by a Board Resolution, the principal purpose of such
transaction is to change the state of incorporation of the Company; and that any
such transaction shall not have as one of its purposes the evasion of the
foregoing limitations.

                  SECTION 5.02. Successor Substituted. Upon any consolidation or
merger, or any sale, conveyance, transfer, lease or other disposition of all or
substantially all of the property and assets of the Company in accordance with
Section 5.01 of this Indenture, the successor Person formed by such
consolidation or into which the Company is merged or to which such sale,
conveyance, transfer, lease or other disposition is made shall succeed to, and
be substituted for, and may exercise every right and power of, the Company under
this Indenture with the same effect as if such successor Person had been named
as the Company herein.


                                   ARTICLE SIX
                              DEFAULT AND REMEDIES

                  SECTION 6.01.  Events of Default.  An "Event of Default" shall
occur with respect to the Notes if:

                  (a) the Company defaults in the payment of the principal of
         (or premium, if any, on) any Note when the same becomes due and payable
         at maturity, upon acceleration, redemption or otherwise, whether or not
         such payment is prohibited by Section Ten;

<PAGE>   59


                                       57

                  (b) the Company defaults in the payment of interest on any
         Note when the same becomes due and payable, and such default continues
         for a period of 30 days whether or not such payment is prohibited by
         Section Ten;

                  (c) the Company defaults in the performance of or breaches the
         provisions of this Indenture applicable to mergers, consolidations and
         transfers of all or substantially all of the assets of the Company or
         fails to make or consummate an Offer to Purchase in accordance with
         Section 4.11 or Section 4.12;

                  (d) the Company defaults in the performance of or breaches any
         other covenant or agreement of the Company in this Indenture or under
         the Notes (other than a default specified in clause (a), (b) or (c)
         above) and such default or breach continues for a period of 30
         consecutive days after written notice by the Trustee or the Holders of
         25% or more in aggregate principal amount of the Notes;

                  (e) there occurs with respect to any issue or issues of
         Indebtedness of the Company or any Significant Subsidiary having an
         outstanding principal amount of $10 million or more in the aggregate
         for all such issues of all such Persons, whether such Indebtedness now
         exists or shall hereafter be created, (I) an event of default that has
         caused the holder thereof to declare such Indebtedness to be due and
         payable prior to its Stated Maturity and such Indebtedness has not been
         discharged in full or such acceleration has not been rescinded or
         annulled within 30 days of such acceleration and/or (II) the failure to
         make a principal payment at the final (but not any interim) fixed
         maturity and such defaulted payment shall not have been made, waived or
         extended within 30 days of such payment default;

                  (f) any final judgment or order (not covered by insurance) for
         the payment of money in excess of $10 million in the aggregate for all
         such final judgments or orders against all such Persons (treating any
         deductibles, self-insurance or retention as not so covered) shall be
         rendered against the Company or any Significant Subsidiary and shall
         not be paid or discharged, and there shall be any period of 30
         consecutive days following entry of the final judgment or order that
         causes the aggregate amount for all such final judgments or orders
         outstanding and not paid or discharged against all such Persons to
         exceed $10 million during which a stay of enforcement of such final
         judgment or order, by reason of a pending appeal or otherwise, shall
         not be in effect;

                  (g) a court having jurisdiction in the premises enters a
         decree or order for (A) relief in respect of the Company or any
         Significant Subsidiary in an involuntary case under any applicable
         bankruptcy, insolvency or other similar law now or hereafter in effect,
         (B) appointment of a receiver, liquidator, assignee, custodian,
         trustee, sequestrator or similar official of the Company or any
         Significant Subsidiary

<PAGE>   60


                                       58

         or for all or substantially all of the property and assets of the
         Company or any Significant Subsidiary or (C) the winding up or
         liquidation of the affairs of the Company or any Significant Subsidiary
         and, in each case, such decree or order shall remain unstayed and in
         effect for a period of 60 consecutive days; or

                  (h) the Company or any Significant Subsidiary (A) commences a
         voluntary case under any applicable bankruptcy, insolvency or other
         similar law now or hereafter in effect, or consents to the entry of an
         order for relief in an involuntary case under any such law, (B)
         consents to the appointment of or taking possession by a receiver,
         liquidator, assignee, custodian, trustee, sequestrator or similar
         official of the Company or any Significant Subsidiary or for all or
         substantially all of the property and assets of the Company or any
         Significant Subsidiary or (C) effects any general assignment for the
         benefit of creditors.

                  SECTION 6.02. Acceleration. If an Event of Default (other than
an Event of Default specified in clause (g) or (h) of Section 6.01 that occurs
with respect to the Company) occurs and is continuing under this Indenture, the
Trustee or the Holders of at least 25% in aggregate principal amount of the
Notes then outstanding, by written notice to the Company (and to the Trustee if
such notice is given by the Holders), may, and the Trustee at the request of
such Holders shall, declare the Accreted Value of, premium, if any, and accrued
interest on the Notes to be immediately due and payable. Upon a declaration of
acceleration (the "Acceleration Notice"), such Accreted Value of, premium, if
any, and accrued interest shall be immediately due and payable; provided,
however, that if there are any amounts outstanding under the Credit Agreement,
such declaration shall not become effective until the earlier of (i) an
acceleration of the Indebtedness under the Credit Agreement and (ii) five
Business Days after receipt by the Company and the Bank Agent of such
Acceleration Notice. In the event of a declaration of acceleration because an
Event of Default set forth in clause (e) of Section 6.01 has occurred and is
continuing, such declaration of acceleration shall be automatically rescinded
and annulled if the event of default triggering such Event of Default pursuant
to clause (e) shall be remedied or cured by the Company or the relevant
Significant Subsidiary or waived by the holders of the relevant Indebtedness
within 60 days after the declaration of acceleration with respect thereto. If an
Event of Default specified in clause (g) or (h) of Section 6.01 occurs with
respect to the Company, the Accreted Value of, premium, if any, and accrued
interest on the Notes then outstanding shall ipso facto become and be
immediately due and payable without any declaration or other act on the part of
the Trustee or any Holder.

                  At any time after such a declaration of acceleration, but
before a judgment or decree for the payment of the money due has been obtained
by the Trustee, the Holders of at least a majority in principal amount of the
outstanding Notes by written notice to the Company and to the Trustee may waive
all past Defaults and rescind and annul such declaration of acceleration and its
consequences if (a) the Company has paid or deposited

<PAGE>   61


                                       59

with the Trustee a sum sufficient to pay (i) all sums paid or advanced by the
Trustee hereunder and the reasonable compensation, expenses, disbursements and
advances of the Trustee, its agents and counsel, (ii) all overdue interest on
all Notes, (iii) the principal of and premium, if any, on any Notes that have
become due otherwise than by such declaration or occurrence of acceleration and
interest thereon at the rate prescribed therefor by such Notes, and (iv) to the
extent that payment of such interest is lawful, interest upon overdue interest
at the rate prescribed therefor by such Notes, (b) all existing Events of
Default, other than the nonpayment of the Accreted Value of, premium, if any,
and accrued interest on the Notes that have become due solely by such
declaration of acceleration, have been cured or waived and (c) the rescission
would not conflict with any judgment or decree of a court of competent
jurisdiction.

                  SECTION 6.03. Other Remedies. If an Event of Default occurs
and is continuing, the Trustee may pursue any available remedy by proceeding at
law or in equity to collect the payment of principal of, premium, if any, or
interest on the Notes or to enforce the performance of any provision of the
Notes or this Indenture.

                  The Trustee may maintain a proceeding even if it does not
possess any of the Notes or does not produce any of them in the proceeding.

                  SECTION 6.04. Waiver of Past Defaults. Subject to Sections
6.02, 6.07 and 9.02, the Holders of at least a majority in principal amount of
the outstanding Notes, by notice to the Trustee, may waive an existing Default
or Event of Default and its consequences, except a Default in the payment of
principal of, premium, if any, or interest on any Note as specified in clause
(a) or (b) of Section 6.01 or in respect of a covenant or provision of this
Indenture which cannot be modified or amended without the consent of the holder
of each outstanding Note affected. Upon any such waiver, such Default shall
cease to exist, and any Event of Default arising therefrom shall be deemed to
have been cured, for every purpose of this Indenture; but no such waiver shall
extend to any subsequent or other Default or Event of Default or impair any
right consequent thereto.

                  SECTION 6.05. Control by Majority. The Holders of at least a
majority in aggregate principal amount of the outstanding Notes may direct the
time, method and place of conducting any proceeding for any remedy available to
the Trustee or exercising any trust or power conferred on the Trustee; provided,
that the Trustee may refuse to follow any direction that conflicts with law or
this Indenture, that may involve the Trustee in personal liability, or that the
Trustee determines in good faith may be unduly prejudicial to the rights of
Holders not joining in the giving of such direction; and provided further, that
the Trustee may take any other action it deems proper that is not inconsistent
with any directions received from Holders of Notes pursuant to this Section
6.05.

<PAGE>   62


                                       60

                  SECTION 6.06. Limitation on Suits. A Holder may not institute
any proceeding, judicial or otherwise, with respect to this Indenture or the
Notes, or for the appointment of a receiver or trustee, or for any other remedy
hereunder, unless:

                  (i) such Holder has previously given to the Trustee written
         notice of a continuing Event of Default;

                  (ii) the Holders of at least 25% in aggregate principal amount
         of outstanding Notes shall have made written request to the Trustee to
         institute proceedings in respect of such Event of Default in its own
         name as Trustee hereunder;

                  (iii) such Holder or Holders have offered to the Trustee
         indemnity reasonably satisfactory to the Trustee against any costs,
         liabilities or expenses to be incurred in compliance with such request;

                  (iv) the Trustee for 60 days after its receipt of such notice,
         request and offer of indemnity has failed to institute any such
         proceeding; and

                  (v) during such 60-day period, the Holders of a majority in
         aggregate principal amount of the outstanding Notes have not given the
         Trustee a direction that is inconsistent with such written request.

                  For purposes of Section 6.05 of this Indenture and this
Section 6.06, the Trustee shall comply with TIA Section 316(a) in making any
determination of whether the Holders of the required aggregate principal amount
of outstanding Notes have concurred in any request or direction of the Trustee
to pursue any remedy available to the Trustee or the Holders with respect to
this Indenture or the Notes or otherwise under the law.

                  A Holder may not use this Indenture to prejudice the rights of
another Holder or to obtain a preference or priority over such other Holder.

                  SECTION 6.07. Rights of Holders to Receive Payment.
Notwithstanding any other provision of this Indenture, the right of any Holder
of a Note to receive payment of the Accreted Value of, premium, if any, or
interest on such Holder's Note on or after the respective due dates expressed on
such Note, or to bring suit for the enforcement of any such payment on or after
such respective dates, shall not be impaired or affected without the consent of
such Holder.

                  SECTION 6.08.  Collection Suit by Trustee.  If an Event of
Default in payment of principal, premium or interest specified in clause (a),
(b) or (c) of Section 6.01 occurs and is continuing, the Trustee may recover
judgment in its own name and as trustee

<PAGE>   63


                                       61

of an express trust against the Company or any other obligor of the Notes for
the whole amount of principal, premium, if any, and accrued interest remaining
unpaid, together with interest on overdue principal, premium, if any, and, to
the extent that payment of such interest is lawful, interest on overdue
installments of interest, in each case at the rate specified in the Notes, and
such further amount as shall be sufficient to cover the costs and expenses of
collection, including the reasonable compensation, expenses, disbursements and
advances of the Trustee, its agents and counsel.

                  SECTION 6.09. Trustee May File Proofs of Claim. The Trustee
may file such proofs of claim and other papers or documents as may be necessary
or advisable in order to have the claims of the Trustee (including any claim for
the reasonable compensation, expenses, disbursements and advances of the
Trustee, its agents and counsel, and any other amounts due the Trustee under
Section 7.07) and the Holders allowed in any judicial proceedings relative to
the Company (or any other obligor of the Notes), its creditors or its property
and shall be entitled and empowered to collect and receive any monies,
securities or other property payable or deliverable upon conversion or exchange
of the Notes or upon any such claims and to distribute the same, and any
custodian, receiver, assignee, trustee, liquidator, sequestrator or other
similar official in any such judicial proceeding is hereby authorized by each
Holder to make such payments to the Trustee and, in the event that the Trustee
shall consent to the making of such payments directly to the Holders, to pay to
the Trustee any amount due to it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agent and counsel, and any other
amounts due the Trustee under Section 7.07. Nothing herein contained shall be
deemed to empower the Trustee to authorize or consent to, or accept or adopt on
behalf of any Holder, any plan of reorganization, arrangement, adjustment or
composition affecting the Notes or the rights of any Holder thereof, or to
authorize the Trustee to vote in respect of the claim of any Holder in any such
proceeding.

                  SECTION 6.10. Priorities. If the Trustee collects any money
         pursuant to this Article Six, it shall pay out the money in the
         following order:

                  First:  to the Trustee for all amounts due under Section 7.07;

                  Second: to Holders for amounts then due and unpaid for
         principal of, premium, if any, and interest on the Notes in respect of
         which or for the benefit of which such money has been collected,
         ratably, without preference or priority of any kind, according to the
         amounts due and payable on such Notes for principal, premium, if any,
         and interest, respectively; and

                  Third:  to the Company or any other obligors of the Notes, as
         their interests may appear, or as a court of competent jurisdiction
         may direct.

<PAGE>   64


                                       62

                  The Trustee, upon prior written notice to the Company, may fix
a record date and payment date for any payment to Holders pursuant to this
Section 6.10.

                  SECTION 6.11. Undertaking for Costs. In any suit for the
enforcement of any right or remedy under this Indenture or in any suit against
the Trustee for any action taken or omitted by it as Trustee, a court may
require any party litigant in such suit to file an undertaking to pay the costs
of the suit, and the court may assess reasonable costs, including reasonable
attorneys' fees, against any party litigant in the suit having due regard to the
merits and good faith of the claims or defenses made by the party litigant. This
Section 6.11 does not apply to a suit by the Trustee, a suit by a Holder
pursuant to Section 6.07 of this Indenture, or a suit by Holders of more than
10% in principal amount of the outstanding Notes.

                  SECTION 6.12. Restoration of Rights and Remedies. If the
Trustee or any Holder has instituted any proceeding to enforce any right or
remedy under this Indenture and such proceeding has been discontinued or
abandoned for any reason, or has been determined adversely to the Trustee or to
such Holder, then, and in every such case, subject to any determination in such
proceeding, the Company, the Trustee and the Holders shall be restored severally
and respectively to their former positions hereunder and thereafter all rights
and remedies of the Company, Trustee and the Holders shall continue as though no
such proceeding had been instituted.

                  SECTION 6.13. Rights and Remedies Cumulative. Except as
otherwise provided with respect to the replacement or payment of mutilated,
destroyed, lost or wrongfully taken Notes in Section 2.09, no right or remedy
herein conferred upon or reserved to the Trustee or to the Holders is intended
to be exclusive of any other right or remedy, and every right and remedy shall,
to the extent permitted by law, be cumulative and in addition to every other
right and remedy given hereunder or now or hereafter existing at law or in
equity or otherwise. The assertion or employment of any right or remedy
hereunder, or otherwise, shall not prevent the concurrent assertion or
employment of any other appropriate right or remedy.

                  SECTION 6.14. Delay or Omission Not Waiver. No delay or
omission of the Trustee or of any Holder to exercise any right or remedy
accruing upon any Event of Default shall impair any such right or remedy or
constitute a waiver of any such Event of Default or an acquiescence therein.
Every right and remedy given by this Article Six or by law to the Trustee or to
the Holders may be exercised from time to time, and as often as may be deemed
expedient, by the Trustee or by the Holders, as the case may be.

<PAGE>   65


                                       63

                                  ARTICLE SEVEN
                                     TRUSTEE

                  SECTION 7.01. General. The duties and responsibilities of the
Trustee shall be as provided by the TIA and as set forth herein. Notwithstanding
the foregoing, no provision of this Indenture shall require the Trustee to
expend or risk its own funds or otherwise incur any financial liability in the
performance of any of its duties hereunder, or in the exercise of any of its
rights or powers, if it shall have reasonable grounds for believing that
repayment of such funds or adequate indemnity against such risk or liability is
not reasonably assured to it. Whether or not therein expressly so provided,
every provision of this Indenture relating to the conduct or affecting the
liability of or affording protection to the Trustee shall be subject to the
provisions of this Article Seven.

                  SECTION 7.02. Certain Rights of Trustee. Subject to TIA
Sections 315(a) through (d):

                  (i) the Trustee may rely and shall be protected in acting or
         refraining from acting upon any resolution, certificate, statement,
         instrument, opinion, report, notice, request, direction, consent,
         order, bond, debenture, note, other evidence of indebtedness or other
         paper or document believed by it to be genuine and to have been signed
         or presented by the proper person. The Trustee need not investigate any
         fact or matter stated in the document;

                  (ii) before the Trustee acts or refrains from acting, it may
         require an Officers' Certificate or an Opinion of Counsel, which shall
         conform to Section 11.04. The Trustee shall not be liable for any
         action it takes or omits to take in good faith in reliance on such
         certificate or opinion;

                  (iii) the Trustee may act through its attorneys and agents and
         shall not be responsible for the misconduct or negligence of any agent
         appointed with due care;

                  (iv) the Trustee shall be under no obligation to exercise any
         of the rights or powers vested in it by this Indenture at the request
         or direction of any of the Holders, unless such Holders shall have
         offered to the Trustee reasonable security or indemnity against the
         costs, expenses and liabilities that might be incurred by it in
         compliance with such request or direction;

                  (v) the Trustee shall not be liable for any action it takes or
         omits to take in good faith that it believes to be authorized or within
         its rights or powers or for any action it takes or omits to take in
         accordance with the direction of the Holders of a majority in principal
         amount at maturity of the Outstanding Notes relating to the time,
         method and place of conducting any proceeding for any remedy available
         to the

<PAGE>   66


                                       64

         Trustee, or exercising any trust or power conferred upon the Trustee,
         under this Indenture; provided that the Trustee's conduct does not
         constitute gross negligence or bad faith;

                  (vi) whenever in the administration of this Indenture the
         Trustee shall deem it desirable that a making be proved or established
         prior to taking, suffering or omitting any action hereunder, the
         Trustee (unless other evidence be herein specifically prescribed) may,
         in the absence of bad faith on its part, rely upon an Officer's
         Certificate; and

                  (vii) the Trustee shall not be bound to make any investigation
         into the facts or matters stated in any resolution, certificate,
         statement, instrument, opinion, report, notice, request, direction,
         consent, order, bond, debenture, note, other evidence of indebtedness
         or other paper or document, but the Trustee, in its discretion, may
         make such further inquiry or investigation into such facts or matters
         as it may see fit, and, if the Trustee shall determine to make such
         further inquiry or investigation, it shall be entitled to examine the
         books, records and premises of the Company personally or by agent or
         attorney.

                  SECTION 7.03. Individual Rights of Trustee. The Trustee, in
its individual or any other capacity, may become the owner or pledgee of Notes
and may otherwise deal with the Company or its Affiliates with the same rights
it would have if it were not the Trustee. Any Agent may do the same with like
rights. However, the Trustee is subject to TIA Sections 310(b) and 311.

                  SECTION 7.04. Trustee's Disclaimer. The Trustee (i) makes no
representation as to the validity or adequacy of this Indenture or the Notes,
(ii) shall not be accountable for the Company's use or application of the
proceeds from the Notes and (iii) shall not be responsible for any statement in
the Notes other than its certificate of authentication.

                  SECTION 7.05. Notice of Default. If any Default or any Event
of Default occurs and is continuing and if such Default or Event of Default is
known to the Trustee, the Trustee shall mail to each Holder in the manner and to
the extent provided in TIA Section 313(c) notice of the Default or Event of
Default within 45 days after it occurs, unless such Default or Event of Default
has been cured; provided, however, that, except in the case of a default in the
payment of the principal of, premium, if any, or interest on any Note, the
Trustee shall be protected in withholding such notice if and so long as the
board of directors, the executive committee or a trust committee of directors
and/or Responsible Officers of the Trustee in good faith determine that the
withholding of such notice is in the interest of the Holders.

<PAGE>   67


                                       65

                  SECTION 7.06. Reports by Trustee to Holders. Within 60 days
after each May 15, beginning with May 15, 1998, the Trustee shall mail to each
Holder as provided in TIA Section 313(c) a brief report dated as of such May 15,
if required by TIA Section 313(a).

                  SECTION 7.07. Compensation and Indemnity. The Company shall
pay to the Trustee such compensation as shall be agreed upon in writing for its
services. The compensation of the Trustee shall not be limited by any law on
compensation of a trustee of an express trust. The Company shall reimburse the
Trustee upon request for all reasonable out-of-pocket expenses and advances
incurred or made by the Trustee. Such expenses shall include the reasonable
compensation and expenses of the Trustee's agents and counsel.

                  The Company shall indemnify the Trustee for, and hold it
harmless against, any loss or liability or expense incurred by it without
negligence or bad faith on its part in connection with the acceptance or
administration of this Indenture and its duties under this Indenture and the
Notes, including the costs and expenses of defending itself against any claim or
liability and of complying with any process served upon it or any of its
officers in connection with the exercise or performance of any of its powers or
duties under this Indenture and the Notes.

                  To secure the Company's payment obligations in this Section
7.07, the Trustee shall have a lien prior to the Notes on all money or property
held or collected by the Trustee, in its capacity as Trustee, except money or
property held in trust to pay principal of, premium, if any, and interest on
particular Notes.

                  If the Trustee incurs expenses or renders services after the
occurrence of an Event of Default specified in clause (g) or (h) of Section
6.01, the expenses and the compensation for the services will be intended to
constitute expenses of administration under Title 11 of the United States
Bankruptcy Code or any applicable federal or state law for the relief of
debtors.

                  SECTION 7.08. Replacement of Trustee. A resignation or removal
of the Trustee and appointment of a successor Trustee shall become effective
only upon the successor Trustee's acceptance of appointment as provided in this
Section 7.08.

                  The Trustee may resign at any time by so notifying the Company
in writing at least 30 days prior to the date of the proposed resignation. The
Holders of a majority in principal amount of the outstanding Notes may remove
the Trustee by so notifying the Trustee in writing and may appoint a successor
Trustee with the consent of the Company. The Company may at any time remove the
Trustee, by Company Order given at least 30 days prior to the date of the
proposed removal.

<PAGE>   68


                                       66

                  If the Trustee resigns or is removed, or if a vacancy exists
in the office of Trustee for any reason, the Company shall promptly appoint a
successor Trustee. Within one year after the successor Trustee takes office, the
Holders of a majority in principal amount of the outstanding Notes may appoint a
successor Trustee to replace the successor Trustee appointed by the Company. If
the successor Trustee does not deliver its written acceptance required by the
next succeeding paragraph of this Section 7.08 within 30 days after the retiring
Trustee resigns or is removed, the retiring Trustee, the Company or the Holders
of a majority in principal amount of the outstanding Notes may petition any
court of competent jurisdiction for the appointment of a successor Trustee.

                  A successor Trustee shall deliver a written acceptance of its
appointment to the retiring Trustee and to the Company. Immediately after the
delivery of such written acceptance, subject to the lien provided in Section
7.07, (i) the retiring Trustee shall transfer all property held by it as Trustee
to the successor Trustee, (ii) the resignation or removal of the retiring
Trustee shall become effective and (iii) the successor Trustee shall have all
the rights, powers and duties of the Trustee under this Indenture. A successor
Trustee shall mail notice of its succession to each Holder.

                  If the Trustee is no longer eligible under Section 7.10, any
Holder who satisfies the requirements of TIA Section 310(b) may petition any
court of competent jurisdiction for the removal of the Trustee and the
appointment of a successor Trustee.

                  The Company shall give notice of any resignation and any
removal of the Trustee and each appointment of a successor Trustee to all
Holders. Each notice shall include the name of the successor Trustee and the
address of its Corporate Trust Office.

                  Notwithstanding replacement of the Trustee pursuant to this
Section 7.08, the Company's obligation under Section 7.07 shall continue for the
benefit of the retiring Trustee.

                  SECTION 7.09. Successor Trustee by Merger, Etc. If the Trustee
consolidates with, merges or converts into, or transfers all or substantially
all of its corporate trust business to, another corporation or national banking
association, the resulting, surviving or transferee corporation or national
banking association without any further act shall be the successor Trustee with
the same effect as if the successor Trustee had been named as the Trustee
herein.

                  SECTION 7.10. Eligibility. This Indenture shall always have a
Trustee who satisfies the requirements of TIA Section 310(a)(1). The Trustee
shall have a combined capital and surplus of at least $25,000,000 as set forth
in its most recent published annual report of condition.

<PAGE>   69


                                       67

                  SECTION 7.11. Money Held in Trust. The Trustee shall not be
liable for interest on any money received by it except as the Trustee may agree
with the Company. Money held in trust by the Trustee need not be segregated from
other funds except to the extent required by law and except for money held in
trust under Article Eight of this Indenture.

                  SECTION 7.12. Withholding Taxes. The Trustee, as agent for the
Company, shall exclude and withhold from each payment of principal and interest
and other amounts due hereunder or under the Notes any and all withholding taxes
applicable thereto as required by law. The Trustee agrees to act as such
withholding agent and, in connection therewith, whenever any present or future
taxes or similar charges are required to be withheld with respect to any amounts
payable in respect of the Notes, to withhold such amounts and timely pay the
same to the appropriate authority in the name of and on behalf of the holders of
the Notes, that it will file any necessary withholding tax returns or statements
when due, and that, as promptly as possible after the payment thereof, it will
deliver to each holder of a Note appropriate documentation showing the payment
thereof, together with such additional documentary evidence as such holders may
reasonably request from time to time.


                                  ARTICLE EIGHT
                             DISCHARGE OF INDENTURE

                  SECTION 8.01.  Termination of Company's Obligations.  Except
as otherwise provided in this Section 8.01, the Company may terminate its
obligations under the Notes and this Indenture if:

                  (i) all Notes previously authenticated and delivered (other
         than destroyed, lost or stolen Notes that have been replaced or Notes
         that are paid pursuant to Section 4.01 or Notes for whose payment money
         or securities have theretofore been held in trust and thereafter repaid
         to the Company, as provided in Section 8.05) have been delivered to the
         Trustee for cancellation and the Company has paid all sums payable by
         it hereunder; or

                  (ii) (A) the Notes mature within one year or all of them are
         to be called for redemption within one year under arrangements
         satisfactory to the Trustee for giving the notice of redemption, (B)
         the Company irrevocably deposits in trust with the Trustee during such
         one-year period, under the terms of an irrevocable trust agreement in
         form and substance satisfactory to the Trustee, as trust funds solely
         for the benefit of the Holders for that purpose, money or U.S.
         Government Obligations sufficient (in the opinion of a nationally
         recognized firm of independent public accountants expressed in a
         written certification thereof delivered to the Trustee), without
         consideration of any reinvestment of any interest thereon, to pay
         principal,

<PAGE>   70


                                       68

         premium, if, any, and interest on the Notes to maturity or redemption,
         as the case may be, and to pay all other sums payable by it hereunder,
         (C) no Default or Event of Default with respect to the Notes shall have
         occurred and be continuing on the date of such deposit, (D) such
         deposit will not result in a breach or violation of, or constitute a
         default under, this Indenture or any other agreement or instrument to
         which the Company is a party or by which it is bound and (E) the
         Company has delivered to the Trustee an Officers' Certificate and an
         Opinion of Counsel, in each case stating that all conditions precedent
         provided for herein relating to the satisfaction and discharge of this
         Indenture have been complied with.

                  With respect to the foregoing clause (i), the Company's
obligations under Section 7.07 shall survive. With respect to the foregoing
clause (ii), the Company's obligations in Sections 2.02, 2.03, 2.04, 2.05, 2.06,
2.07, 2.08, 2.09, 2.14, 4.01, 4.02, 7.07, 7.08, 8.04, 8.05 and 8.06 shall
survive until the Notes are no longer outstanding. Thereafter, only the
Company's obligations in Sections 7.07, 8.05 and 8.06 shall survive. After any
such irrevocable deposit, the Trustee upon request shall acknowledge in writing
the discharge of the Company's obligations under the Notes and this Indenture
except for those surviving obligations specified above.

                  SECTION 8.02. Defeasance and Discharge of Indenture. The
Company will be deemed to have paid and will be discharged from any and all
obligations in respect of the Notes on the 123rd day after the date of the
deposit referred to in clause (A) of this Section 8.02, and the provisions of
this Indenture will no longer be in effect with respect to the Notes, and the
Trustee, at the expense of the Company, shall execute proper instruments
acknowledging the same, except as to (i) rights of registration of transfer and
exchange, (ii) substitution of apparently mutilated, defaced, destroyed, lost or
stolen Notes, (iii) rights of Holders to receive payments of principal thereof
and interest thereon, (iv) the Company's obligations under Section 4.02, (v) the
rights, obligations and immunities of the Trustee hereunder and (vi) the rights
of the Holders as beneficiaries of this Indenture with respect to the property
so deposited with the Trustee payable to all or any of them; provided that the
following conditions shall have been satisfied:

                  (A) with reference to this Section 8.02, the Company has
         irrevocably deposited or caused to be irrevocably deposited with the
         Trustee (or another trustee satisfying the requirements of Section 7.10
         of this Indenture) and conveyed all right, title and interest for the
         benefit of the Holders, under the terms of an irrevocable trust
         agreement in form and substance satisfactory to the Trustee as trust
         funds in trust, specifically pledged to the Trustee for the benefit of
         the Holders as security for payment of the principal of, premium, if
         any, and interest, if any, on the Notes, and dedicated solely to, the
         benefit of the Holders, in and to (1) money in an amount, (2) U.S.
         Government Obligations that, through the payment of interest, premium,
         if any, and principal in respect thereof in accordance with their
         terms, will provide, not

<PAGE>   71


                                       69

         later than one day before the due date of any payment referred to in
         this clause (A), money in an amount or (3) a combination thereof in an
         amount sufficient, in the opinion of a nationally recognized firm of
         independent public accountants expressed in a written certification
         thereof delivered to the Trustee, to pay and discharge, without
         consideration of the reinvestment of such interest and after payment of
         all federal, state and local taxes or other charges and assessments in
         respect thereof payable by the Trustee, the principal of, premium, if
         any, and accrued interest on the outstanding Notes at the Stated
         Maturity of such principal or interest; provided that the Trustee shall
         have been irrevocably instructed to apply such money or the proceeds of
         such U.S. Government Obligations to the payment of such principal,
         premium, if any, and interest with respect to the Notes;

                  (B) such deposit will not result in a breach or violation of,
         or constitute a default under, this Indenture or any other agreement or
         instrument to which the Company is a party or by which it is bound;

                  (C) immediately after giving effect to such deposit on a pro
         forma basis, no Default or Event of Default shall have occurred and be
         continuing on the date of such deposit or during the period ending on
         the 123rd day after such date of deposit;

                  (D) the Company shall have delivered to the Trustee (1) either
         (x) a ruling directed to the Trustee received from the Internal Revenue
         Service to the effect that the Holders will not recognize income, gain
         or loss for federal income tax purposes as a result of the Company's
         exercise of its option under this Section 8.02 and will be subject to
         federal income tax on the same amount and in the same manner and at the
         same times as would have been the case if such option had not been
         exercised or (y) an Opinion of Counsel to the same effect as the ruling
         described in clause (x) above accompanied by a ruling to that effect
         published by the Internal Revenue Service, unless there has been a
         change in the applicable federal income tax law since the Closing Date
         such that a ruling from the Internal Revenue Service is no longer
         required and (2) an Opinion of Counsel to the effect that (x) the
         creation of the defeasance trust does not violate the Investment
         Company Act of 1940 and (y) after the passage of 123 days following the
         deposit (except, with respect to any trust funds for the account of any
         Holder who may be deemed to be an "insider" for purposes of the United
         States Bankruptcy Code, after one year following the deposit), the
         trust funds will not be subject to the effect of Section 547 of the
         United States Bankruptcy Code or Section 15 of the New York Debtor and
         Creditor Law in a case commenced by or against the Company under either
         such statute, and either (I) the trust funds will no longer remain the
         property of the Company (and therefore will not be subject to the
         effect of any applicable bankruptcy, insolvency, reorganization or
         similar laws affecting creditors' rights generally) or (II) if a court
         were to rule under any such law in any case or proceeding that the
         trust funds remained property of the Company,

<PAGE>   72


                                       70

         (a) assuming such trust funds remained in the possession of the Trustee
         prior to such court ruling to the extent not paid to the Holders, the
         Trustee will hold, for the benefit of the Holders, a valid and
         perfected security interest in such trust funds that is not avoidable
         in bankruptcy or otherwise except for the effect of Section 552(b) of
         the United States Bankruptcy Code on interest on the trust funds
         accruing after the commencement of a case under such statute and (b)
         the Holders will be entitled to receive adequate protection of their
         interests in such trust funds if such trust funds are used in such case
         or proceeding;

                  (E) the Company is not prohibited from making payments in
         respect of the Notes by the provisions of Section Ten;

                  (F) if the Notes are then listed on a national securities
         exchange, the Company shall have delivered to the Trustee an Opinion of
         Counsel to the effect that such deposit defeasance and discharge will
         not cause the Notes to be delisted; and

                  (G) the Company has delivered to the Trustee an Officers'
         Certificate and an Opinion of Counsel, in each case stating that all
         conditions precedent provided for herein relating to the defeasance
         contemplated by this Section 8.02 have been complied with.

                  Notwithstanding the foregoing, prior to the end of the 123-day
(or one year) period referred to in clause (D)(2)(y) of this Section 8.02, none
of the Company's obligations under this Indenture shall be discharged.
Subsequent to the end of such 123-day (or one year) period with respect to this
Section 8.02, the Company's obligations in Sections 2.02, 2.03, 2.04, 2.05,
2.06, 2.07, 2.08, 2.09, 2.14, 4.01, 4.02, 7.07, 7.08, 8.05 and 8.06 shall
survive until the Notes are no longer outstanding. Thereafter, only the
Company's obligations in Sections 7.07, 8.05 and 8.06 shall survive. If and when
a ruling from the Internal Revenue Service or an Opinion of Counsel referred to
in clause (D)(1) of this Section 8.02 is able to be provided specifically
without regard to, and not in reliance upon, the continuance of the Company's
obligations under Section 4.01, then the Company's obligations under such
Section 4.01 shall cease upon delivery to the Trustee of such ruling or Opinion
of Counsel and compliance with the other conditions precedent provided for
herein relating to the defeasance contemplated by this Section 8.02.

                  After any such irrevocable deposit, the Trustee upon request
shall acknowledge in writing the discharge of the Company's obligations under
the Notes and this Indenture except for those surviving obligations in the
immediately preceding paragraph.

                  SECTION 8.03.  Defeasance of Certain Obligations.  The Company
may omit to comply with any term, provision or condition set forth in clauses
(iii) and (iv) of Section 5.01 and Sections 4.03 through 4.18, and clause (c) of
Section 6.01 with respect to

<PAGE>   73


                                       71

clauses (iii) and (iv) of Section 5.01, and clause (d) of Section 6.01 with
respect to Sections 4.03 through 4.18 and clauses (e) and (f) of Section 6.01
shall be deemed not to be Events of Default, in each case with respect to the
outstanding Notes if:

                  (i) with reference to this Section 8.03, the Company has
         irrevocably deposited or caused to be irrevocably deposited with the
         Trustee (or another trustee satisfying the requirements of Section
         7.10) and conveyed all right, title and interest to the Trustee for the
         benefit of the Holders, under the terms of an irrevocable trust
         agreement in form and substance satisfactory to the Trustee as trust
         funds in trust, specifically pledged to the Trustee for the benefit of
         the Holders as security for payment of the principal of, premium, if
         any, and interest, if any, on the Notes, and dedicated solely to, the
         benefit of the Holders, in and to (A) money in an amount, (B) U.S.
         Government Obligations that, through the payment of interest and
         principal in respect thereof in accordance with their terms, will
         provide, not later than one day before the due date of any payment
         referred to in this clause (i), money in an amount or (C) a combination
         thereof in an amount sufficient, in the opinion of a nationally
         recognized firm of independent public accountants expressed in a
         written certification thereof delivered to the Trustee, to pay and
         discharge, without consideration of the reinvestment of such interest
         and after payment of all federal, state and local taxes or other
         charges and assessments in respect thereof payable by the Trustee, the
         principal of, premium, if any, and interest on the outstanding Notes on
         the Stated Maturity of such principal or interest; provided that the
         Trustee shall have been irrevocably instructed to apply such money or
         the proceeds of such U.S. Government Obligations to the payment of such
         principal, premium, if any, and interest with respect to the Notes;

                  (ii) such deposit will not result in a breach or violation of,
         or constitute a default under, this Indenture or any other agreement or
         instrument to which the Company is a party or by which it is bound;

                  (iii) no Default or Event of Default shall have occurred and
         be continuing on the date of such deposit;

                  (iv) the Company has delivered to the Trustee an Opinion of
         Counsel to the effect that (A) the creation of the defeasance trust
         does not violate the Investment Company Act of 1940, (B) the Holders
         have a valid first-priority security interest in the trust funds, (C)
         the Holders will not recognize income, gain or loss for federal income
         tax purposes as a result of such deposit and defeasance of certain
         obligations and will be subject to federal income tax on the same
         amount and in the same manner and at the same times as would have been
         the case if such deposit and defeasance had not occurred and (D) after
         the passage of 123 days following the deposit (except, with respect to
         any trust funds for the account of any Holder who may be deemed to be
         an

<PAGE>   74


                                       72

         "insider" for purposes of the United States Bankruptcy Code, after one
         year following the deposit), the trust funds will not be subject to the
         effect of Section 547 of the United States Bankruptcy Code or Section
         15 of the New York Debtor and Creditor Law in a case commenced by or
         against the Company under either such statute, and either (1) the trust
         funds will no longer remain the property of the Company (and therefore
         will not be subject to the effect of any applicable bankruptcy,
         insolvency, reorganization or similar laws affecting creditors' rights
         generally) or (2) if a court were to rule under any such law in any
         case or proceeding that the trust funds remained property of the
         Company, (x) assuming such trust funds remained in the possession of
         the Trustee prior to such court ruling to the extent not paid to the
         Holders, the Trustee will hold, for the benefit of the Holders, a valid
         and perfected security interest in such trust funds that is not
         avoidable in bankruptcy or otherwise (except for the effect of Section
         552(b) of the United States Bankruptcy Code on interest on the trust
         funds accruing after the commencement of a case under such statute),
         (y) the Holders will be entitled to receive adequate protection of
         their interests in such trust funds if such trust funds are used in
         such case or proceeding and (z) no property, rights in property or
         other interests granted to the Trustee or the Holders in exchange for,
         or with respect to, such trust funds will be subject to any prior
         rights of holders of other Indebtedness of the Company or any of its
         Subsidiaries;

                  (v) the Company is not prohibited from making payments in
         respect of the Notes by the provisions of Section Ten;

                  (vi) if the Notes are then listed on a national securities
         exchange, the Company shall have delivered to the Trustee an Opinion of
         Counsel to the effect that such deposit defeasance and discharge will
         not cause the Notes to be delisted; and

                  (vii) the Company has delivered to the Trustee an Officers'
         Certificate and an Opinion of Counsel, in each case stating that all
         conditions precedent provided for herein relating to the defeasance
         contemplated by this Section 8.03 have been complied with.

                  SECTION 8.04. Application of Trust Money. Subject to Section
8.06, the Trustee or Paying Agent shall hold in trust money or U.S. Government
Obligations deposited with it pursuant to Section 8.01, 8.02 or 8.03, as the
case may be, and shall apply the deposited money and the money from U.S.
Government Obligations in accordance with the Notes and this Indenture to the
payment of principal of, premium, if any, and interest on the Notes; but such
money need not be segregated from other funds except to the extent required by
law.

<PAGE>   75


                                       73

                  SECTION 8.05. Repayment to Company. Subject to Sections 7.07,
8.01, 8.02 and 8.03, the Trustee and the Paying Agent shall promptly pay to the
Company upon request set forth in an Officers' Certificate any excess money held
by them at any time and thereupon shall be relieved from all liability with
respect to such money. The Trustee and the Paying Agent shall pay to the Company
upon request any money held by them for the payment of principal, premium, if
any, or interest that remains unclaimed for two years; provided that the Trustee
or such Paying Agent before being required to make any payment may cause to be
published at the expense of the Company once in a newspaper of general
circulation in the City of New York or mail to each Holder entitled to such
money at such Holder's address (as set forth in the Note Register) notice that
such money remains unclaimed and that after a date specified therein (which
shall be at least 30 days from the date of such publication or mailing) any
unclaimed balance of such money then remaining will be repaid to the Company.
After payment to the Company, Holders entitled to such money must look to the
Company for payment as general creditors unless an applicable law designates
another Person, and all liability of the Trustee and such Paying Agent with
respect to such money shall cease.

                  SECTION 8.06. Reinstatement. If the Trustee or Paying Agent is
unable to apply any money or U.S. Government Obligations in accordance with
Section 8.01, 8.02 or 8.03, as the case may be, by reason of any legal
proceeding or by reason of any order or judgment of any court or governmental
authority enjoining, restraining or otherwise prohibiting such application, the
Company's obligations under this Indenture and the Notes shall be revived and
reinstated as though no deposit had occurred pursuant to Section 8.01, 8.02 or
8.03, as the case may be, until such time as the Trustee or Paying Agent is
permitted to apply all such money or U.S. Government Obligations in accordance
with Section 8.01, 8.02 or 8.03, as the case may be; provided that, if the
Company has made any payment of principal of, premium, if any, or interest on
any Notes because of the reinstatement of its obligations, the Company shall be
subrogated to the rights of the Holders of such Notes to receive such payment
from the money or U.S. Government Obligations held by the Trustee or Paying
Agent.


                                  ARTICLE NINE
                       AMENDMENTS, SUPPLEMENTS AND WAIVERS

                  SECTION 9.01. Without Consent of Holders. The Company, when
authorized by a resolution of its Board of Directors, and the Trustee may amend
or supplement this Indenture or the Notes without notice to or the consent of
any Holder:

                  (1) to cure any ambiguity, defect or inconsistency in the
         Indenture; provided that such amendments or supplements shall not
         adversely affect the interests of the Holders in any material respect;

<PAGE>   76


                                       74


                  (2) to comply with Article Five;

                  (3) to comply with any requirements of the Commission in
         connection with the qualification of this Indenture under the TIA;

                  (4)      to evidence and provide for the acceptance of
         appointment hereunder by a successor Trustee; or

                  (5) to make any change that, in the good faith opinion of the
         Board of Directors as evidenced by a Board Resolution, does not
         materially and adversely affect the rights of any Holder.

                  SECTION 9.02. With Consent of Holders. Subject to Sections
6.04 and 6.07 and without prior notice to the Holders, the Company, when
authorized by its Board of Directors (as evidenced by a Board Resolution), and
the Trustee may amend this Indenture and the Notes with the written consent of
the Holders of a majority in principal amount of the Notes then outstanding, and
the Holders of a majority in principal amount of the Notes then outstanding by
written notice to the Trustee may waive future compliance by the Company with
any provision of this Indenture or the Notes.

                  Notwithstanding the provisions of this Section 9.02, without
the consent of each Holder affected, an amendment or waiver, including a waiver
pursuant to Section 6.04, may not:

                  (i) change the Stated Maturity of the principal of, or any
         installment of interest on, any Note, or reduce the Accreted Value or
         principal amount thereof or the rate of interest thereon or any premium
         payable upon the redemption thereof, or adversely affect any right of
         repayment at the option of any Holder of any Note, or change any place
         of payment where, or the currency in which, any Note or any premium or
         the interest thereon is payable, or impair the right to institute suit
         for the enforcement of any such payment on or after the Stated Maturity
         thereof (or, in the case of redemption, on or after the Redemption
         Date);

                  (ii) reduce the percentage in principal amount of outstanding
         Notes the consent of whose Holders is required for any such
         supplemental indenture, for any waiver of compliance with certain
         provisions of this Indenture or certain Defaults and their consequences
         provided for in this Indenture;

                  (iii) waive a Default in the payment of principal of, premium,
         if any, or interest on, any Note;

<PAGE>   77


                                       75

                  (iv)     modify the provisions of Section Ten in a manner
         adverse to the Holders; or

                  (v) modify any of the provisions of this Section 9.02, except
         to increase any such percentage or to provide that certain other
         provisions of this Indenture cannot be modified or waived without the
         consent of the Holder of each outstanding Note affected thereby.

                  It shall not be necessary for the consent of the Holders under
this Section 9.02 to approve the particular form of any proposed amendment,
supplement or waiver, but it shall be sufficient if such consent approves the
substance thereof.

                  After an amendment, supplement or waiver under this Section
9.02 becomes effective, the Company shall mail to the Holders affected thereby a
notice briefly describing the amendment, supplement or waiver. The Company will
mail supplemental indentures to Holders upon request. Any failure of the Company
to mail such notice, or any defect therein, shall not, however, in any way
impair or affect the validity of any such supplemental indenture or waiver.

                  SECTION 9.03. Revocation and Effect of Consent. Until an
amendment or waiver becomes effective, a consent to it by a Holder is a
continuing consent by the Holder and every subsequent Holder of a Note or
portion of a Note that evidences the same debt as the Note of the consenting
Holder, even if notation of the consent is not made on any Note. However, any
such Holder or subsequent Holder may revoke the consent as to its Note or
portion of its Note. Such revocation shall be effective only if the Trustee
receives the notice of revocation before the date the amendment, supplement or
waiver becomes effective. An amendment, supplement or waiver shall become
effective on receipt by the Trustee of written consents from the Holders of the
requisite percentage in principal amount of the outstanding Notes.

                  The Company may, but shall not be obligated to, fix a record
date for the purpose of determining the Holders entitled to consent to any
amendment, supplement or waiver. If a record date is fixed, then,
notwithstanding the last two sentences of the immediately preceding paragraph,
those persons who were Holders at such record date (or their duly designated
proxies) and only those persons shall be entitled to consent to such amendment,
supplement or waiver or to revoke any consent previously given, whether or not
such persons continue to be Holders after such record date. No such consent
shall be valid or effective for more than 90 days after such record date.

                  After an amendment, supplement or waiver becomes effective, it
shall bind every Holder unless it is of the type described in any of clauses (i)
through (v) of Section 9.02. In case of an amendment or waiver of the type
described in clauses (i) through

<PAGE>   78


                                       76

(v) of Section 9.02, the amendment or waiver shall bind each Holder who has
consented to it and every subsequent Holder of a Note that evidences the same
indebtedness as the Note of the consenting Holder.

                  SECTION 9.04. Notation on or Exchange of Notes. If an
amendment, supplement or waiver changes the terms of a Note, the Trustee may
require the Holder to deliver it to the Trustee. The Trustee may place an
appropriate notation on the Note about the changed terms and return it to the
Holder and the Trustee may place an appropriate notation on any Note thereafter
authenticated. Alternatively, if the Company or the Trustee so determines, the
Company in exchange for the Note shall issue and the Trustee shall authenticate
a new Note that reflects the changed terms.

                  SECTION 9.05. Trustee to Sign Amendments, Etc. The Trustee
shall be entitled to receive, and shall be fully protected in relying upon, an
Opinion of Counsel stating that the execution of any amendment, supplement or
waiver authorized pursuant to this Article Nine is authorized or permitted by
this Indenture. Subject to the preceding sentence, the Trustee shall sign such
amendment, supplement or waiver if the same does not adversely affect the rights
of the Trustee. The Trustee may, but shall not be obligated to, execute any such
amendment, supplement or waiver that affects the Trustee's own rights, duties or
immunities under this Indenture or otherwise.

                  SECTION 9.06. Conformity with Trust Indenture Act. Every
supplemental indenture executed pursuant to this Article Nine shall conform to
the requirements of the TIA as then in effect.


                                   ARTICLE TEN
                             SUBORDINATION OF NOTES

                  SECTION 10.01. Notes Subordinated to Senior Indebtedness. The
Company and the Trustee each covenants and agrees, and each Holder, by its
acceptance of a Note, likewise covenants and agrees that all Notes shall be
issued subject to the provisions of this Article Ten; and each Person holding
any Note, whether upon original issue or upon transfer, assignment or exchange
thereof, accepts and agrees that Senior Subordinated Obligations shall, to the
extent and in the manner set forth in this Article Ten, be subordinated in right
of payment to the prior payment in full, in cash or cash equivalents, of all
amounts payable under Senior Indebtedness (including any interest accruing
subsequent to an event specified in Sections 6.01(g) and 6.01(h) of this
Indenture, whether or not such interest is an allowed claim enforceable against
the debtor under the United States Bankruptcy Code).

                  SECTION 10.02. No Payment on Notes in Certain Circumstances.
(a) No direct or indirect payment by or on behalf of the Company of Senior
Subordinated Obligations, whether pursuant to the terms of the Notes or upon
acceleration or otherwise,

<PAGE>   79


                                       77

shall be made if, at the time of such payment, there exists a default in the
payment of all or any portion of the obligations of any Senior Indebtedness of
the Company (including, without limitation, a payment default arising from the
acceleration of any Senior Indebtedness), and such default shall not have been
cured or waived or the benefits of this sentence waived by or on behalf of the
holders of such Senior Indebtedness.

                  (b) During the continuance of any other event of default with
respect to any Designated Senior Indebtedness pursuant to which the maturity
thereof may be accelerated, upon receipt by the Trustee of written notice from
the trustee or other representative for the holders of such other Designated
Senior Indebtedness (or the holders of at least a majority in principal amount
of such Designated Senior Indebtedness then outstanding), no payment of Senior
Subordinated Obligations may be made by or on behalf of the Company upon or in
respect of the Notes for a period (a "Payment Blockage Period") commencing on
the date of receipt of such notice and ending 179 days thereafter (unless, in
each case, such Payment Blockage Period shall be terminated by written notice to
the Trustee from such trustee of, or other representatives for, such holders or
by repayment in full in cash or cash equivalents of such Designated Senior
Indebtedness). Not more than one Payment Blockage Period may be commenced with
respect to the Notes during any period of 360 consecutive days; provided that,
subject to the limitation contained in the next sentence, the commencement of a
Payment Blockage Period by the representatives for, or the holders of,
Designated Senior Indebtedness other than under the Credit Agreement shall not
bar the commencement of another Payment Blockage Period by the Bank Agent within
such period of 360 consecutive days. Notwithstanding anything in this Indenture
to the contrary, there must be 180 consecutive days in any 360-day period in
which no Payment Blockage Period is in effect. For all purposes of this Section
10.02(b), no event of default that existed or was continuing (it being
acknowledged that any subsequent action that would give rise to an event of
default pursuant to any provision under which an event of default previously
existed or was continuing shall constitute a new event of default for this
purpose) on the date of the commencement of any Payment Blockage Period with
respect to the Designated Senior Indebtedness initiating such Payment Blockage
Period shall be, or shall be made, the basis for the commencement of a second
Payment Blockage Period by the representative for, or the holders of, such
Designated Senior Indebtedness, whether or not within a period of 360
consecutive days, unless such event of default shall have been cured or waived
for a period of not less than 90 consecutive days.

                  (c) In the event that, notwithstanding the foregoing, any
payment shall be received by the Trustee or any Holder when such payment is
prohibited by Section 10.02(a) or 10.02(b) of this Indenture, the Trustee shall
promptly notify the holders of Senior Indebtedness of such prohibited payment
and such payment shall be held in trust for the benefit of, and shall be paid
over or delivered to, the holders of Senior Indebtedness or their respective
representatives, or to the trustee or trustees under any indenture pursuant to
which any of such Senior Indebtedness may have been issued, as their respective
interests may appear, but only to the extent that, upon notice from the Trustee
to the holders of Senior Indebtedness that such prohibited payment has been
made, the holders of the Senior

<PAGE>   80


                                       78

Indebtedness (or their representative or representatives of a trustee) within 30
days of receipt of such notice from the Trustee notify the Trustee of the
amounts then due and owing on the Senior Indebtedness, if any, and only the
amounts specified in such notice to the Trustee shall be paid to the holders of
Senior Indebtedness and any excess above such amounts due and owing on Senior
Indebtedness shall be paid to the Company.

                  SECTION 10.03. Payment over Proceeds upon Dissolution, Etc.
(a) Upon any payment or distribution of assets or securities of the Company of
any kind or character, whether in cash, property or securities, upon any
dissolution or winding up or total or partial liquidation or reorganization of
the Company, whether voluntary or involuntary, or in bankruptcy, insolvency,
receivership or other proceedings, all amounts due or to become due upon all
Senior Indebtedness (including any interest accruing subsequent to an event
specified in Sections 6.01(g) and 6.01(h) of this Indenture, whether or not such
interest is an allowed claim enforceable against the debtor under the United
States Bankruptcy Code) shall first be paid in full, in cash or cash
equivalents, before the Holders or the Trustee on their behalf shall be entitled
to receive any payment by the Company on account of Senior Subordinated
Obligations, or any payment to acquire any of the Notes for cash, property or
securities, or any distribution with respect to the Notes of any cash, property
or securities. Before any payment may be made by, or on behalf of, the Company
on any Senior Subordinated Obligations upon any such dissolution, winding up,
liquidation or reorganization, any payment or distribution of assets or
securities of the Company of any kind or character, whether in cash, property or
securities, to which the Holders or the Trustee on their behalf would be
entitled, but for the provisions of this Article Ten, shall be made by the
Company or by any receiver, trustee in bankruptcy, liquidating trustee, agent or
other similar Person making such payment or distribution, or by the Holders or
the Trustee if received by them or it, directly to the holders of Senior
Indebtedness (pro rata to such holders on the basis of the respective amounts of
Senior Indebtedness held by such holders) or their representatives or to any
trustee or trustees under any indenture pursuant to which any such Senior
Indebtedness may have been issued, as their respective interests appear, to the
extent necessary to pay all such Senior Indebtedness in full, in cash or cash
equivalents after giving effect to any concurrent payment, distribution or
provision therefor to or for the holders of such Senior Indebtedness.

                  (b) To the extent any payment of Senior Indebtedness (whether
by or on behalf of the Company, as proceeds of security or enforcement of any
right of setoff or otherwise) is declared to be fraudulent or preferential, set
aside or required to be paid to any receiver, trustee in bankruptcy, liquidating
trustee, agent or other similar Person under any bankruptcy, insolvency,
receivership, fraudulent conveyance or similar law, then if such payment is
recovered by, or paid over to, such receiver, trustee in bankruptcy, liquidating
trustee, agent or other similar Person, the Senior Indebtedness or part thereof
originally intended to be satisfied shall be deemed to be reinstated and
outstanding as if such payment had not occurred. To the extent the obligation to
repay any Senior Indebtedness is declared to be fraudulent, invalid, or
otherwise set aside under any bankruptcy, insolvency, receivership, fraudulent
conveyance or similar law, then the obligations so declared

<PAGE>   81


                                       79

fraudulent, invalid or otherwise set aside (and all other amounts that would
come due with respect thereto had such obligation not been so affected) shall be
deemed to be reinstated and outstanding as Senior Indebtedness for all purposes
hereof as if such declaration, invalidity or setting aside had not occurred.

                  (c) In the event that, notwithstanding the foregoing provision
prohibiting such payment or distribution, any payment or distribution of assets
or securities of the Company of any kind or character, whether in cash, property
or securities, shall be received by the Trustee or any Holder at a time when
such payment or distribution is prohibited by Section 10.03(a) of this Indenture
and before all obligations in respect of Senior Indebtedness are paid in full,
in cash or cash equivalents, such payment or distribution shall be received and
held in trust for the benefit of, and shall be paid over or delivered to, the
holders of Senior Indebtedness (pro rata to such holders on the basis of such
respective amount of Senior Indebtedness held by such holders) or their
representatives, or to the trustee or trustees under any indenture pursuant to
which any such Senior Indebtedness may have been issued, as their respective
interests appear, for application to the payment of Senior Indebtedness
remaining unpaid until all such Senior Indebtedness has been paid in full, in
cash or cash equivalents, after giving effect to any concurrent payment,
distribution or provision therefor to or for the holders of such Senior
Indebtedness.

                  (d) For purposes of this Section 10.03, the words "cash,
property or securities" shall not be deemed to include, so long as the effect of
this clause is not to cause the Notes to be treated in any case or proceeding or
similar event described in this Section 10.03 as part of the same class of
claims as the Senior Indebtedness or any class of claims pari passu with, or
senior to, the Senior Indebtedness for any payment or distribution, securities
of the Company or any other corporation provided for by a plan of reorganization
or readjustment that are subordinated, at least to the extent that the Notes are
subordinated, to the payment of all Senior Indebtedness then outstanding;
provided that (1) if a new corporation results from such reorganization or
readjustment, such corporation assumes the Senior Indebtedness and (2) the
rights of the holders of the Senior Indebtedness are not, without the consent of
such holders, altered by such reorganization or readjustment. The consolidation
of the Company with, or the merger of the Company with or into, another
corporation or the liquidation or dissolution of the Company following the sale,
conveyance, transfer, lease or other disposition of all or substantially all of
its property and assets to another corporation upon the terms and conditions
provided in Article Five of this Indenture (including in connection with the
Acquisition) shall not be deemed a dissolution, winding up, liquidation or
reorganization for the purposes of this Section 10.03 if such other corporation
shall, as a part of such consolidation, merger, sale, conveyance, transfer,
lease or other disposition, comply (to the extent required) with the conditions
stated in Article Five of this Indenture.

                  SECTION 10.04.  Subrogation.  (a)  Upon the payment in full of
all Senior Indebtedness in cash or cash equivalents, the Holders shall be
subrogated to the rights of the

<PAGE>   82


                                       80

holders of Senior Indebtedness to receive payments or distributions of cash,
property or securities of the Company made on such Senior Indebtedness until the
principal of, premium, if any, and interest on the Notes shall be paid in full;
and, for the purposes of such subrogation, no payments or distributions to the
holders of the Senior Indebtedness of any cash, property or securities to which
the Holders or the Trustee on their behalf would be entitled except for the
provisions of this Article Ten, and no payment pursuant to the provisions of
this Article Ten to the holders of Senior Indebtedness by Holders or the Trustee
on their behalf shall, as between the Company, its creditors other than holders
of Senior Indebtedness, and the Holders, be deemed to be a payment by the
Company to or on account of the Senior Indebtedness. It is understood that the
provisions of this Article Ten are intended solely for the purpose of defining
the relative rights of the Holders, on the one hand, and the holders of the
Senior Indebtedness, on the other hand.

                  (b) If any payment or distribution to which the Holders would
otherwise have been entitled but for the provisions of this Article Ten shall
have been applied, pursuant to the provisions of this Article Ten, to the
payment of all amounts payable under Senior Indebtedness, then, and in such
case, the Holders shall be entitled to receive from the holders of such Senior
Indebtedness any payments or distributions received by such holders of Senior
Indebtedness in excess of the amount required to make payment in full, in cash
or cash equivalents, of such Senior Indebtedness of such holders.

                  SECTION 10.05. Obligations of Company Unconditional. (a)
Nothing contained in this Article Ten or elsewhere in this Indenture or in the
Notes is intended to or shall impair, as among the Company and the Holders, the
obligation of the Company, which is absolute and unconditional, to pay to the
Holders the principal of, premium, if any, and interest on the Notes as and when
the same shall become due and payable in accordance with their terms, or is
intended to or shall affect the relative rights of the Holders and creditors of
the Company other than the holders of the Senior Indebtedness, nor shall
anything herein or therein prevent the Holders or the Trustee on their behalf
from exercising all remedies otherwise permitted by applicable law upon Default
under this Indenture, subject to the rights, if any, under this Article Ten of
the holders of the Senior Indebtedness.

                  (b) Without limiting the generality of the foregoing, nothing
contained in this Article Ten will restrict the right of the Trustee or the
Holders to take any action to declare the Notes to be due and payable prior to
their Stated Maturity pursuant to Section 6.01 of this Indenture or to pursue
any rights or remedies hereunder; provided, however, that all Senior
Indebtedness then due and payable or thereafter declared to be due and payable
shall first be paid in full, in cash or cash equivalents, before the Holders or
the Trustee are entitled to receive any direct or indirect payment from the
Company of Senior Subordinated Obligations.

                  SECTION 10.06.  Notice to Trustee.  The Company shall give
prompt written notice to the Trustee of any fact known to the Company that would
prohibit the making of any payment to or by the Trustee in respect of the Notes
pursuant to the provisions of this

<PAGE>   83


                                       81

Article Ten. The Trustee shall not be charged with the knowledge of the
existence of any default or event of default with respect to any Senior
Indebtedness or of any other facts that would prohibit the making of any payment
to or by the Trustee unless and until the Trustee shall have received notice in
writing at its Corporate Trust Office to that effect signed by an Officer of the
Company, or by a holder of Senior Indebtedness or trustee or agent thereof; and
prior to the receipt of any such written notice, the Trustee shall, subject to
Article Seven, be entitled to assume that no such facts exist; provided that, if
the Trustee shall not have received the notice provided for in this Section
10.06 at least two Business Days prior to the date upon which, by the terms of
this Indenture, any monies shall become payable for any purpose (including,
without limitation, the payment of the principal of, premium, if any, or
interest on any Note), then, notwithstanding anything herein to the contrary,
the Trustee shall have full power and authority to receive any monies from the
Company and to apply the same to the purpose for which they were received, and
shall not be affected by any notice to the contrary that may be received by it
on or after such prior date except for an acceleration of the Notes prior to
such application. Nothing contained in this Section 10.06 shall limit the right
of the holders of Senior Indebtedness to recover payments as contemplated by
this Article Ten. The foregoing shall not apply if the Payment Agent is the
Company. The Trustee shall be entitled to rely on the delivery to it of a
written notice by a Person representing himself or itself to be a holder of any
Senior Indebtedness (or a trustee on behalf of, or other representative of, such
holder) to establish that such notice has been given by a holder of such Senior
Indebtedness or a trustee or representative on behalf of any such holder.

                  (b) In the event that the Trustee determines in good faith
that any evidence is required with respect to the right of any Person as a
holder of Senior Indebtedness to participate in any payment or distribution
pursuant to this Article Ten, the Trustee may request such Person to furnish
evidence to the reasonable satisfaction of the Trustee as to the amount of
Senior Indebtedness held by such Person, the extent to which such Person is
entitled to participate in such payment or distribution and any other facts
pertinent to the rights of such Person under this Article Ten and, if such
evidence is not furnished to the Trustee, the Trustee may defer any payment to
such Person pending judicial determination as to the right of such Person to
receive such payment.

                  SECTION 10.07. Reliance on Judicial Order or Certificate of
Liquidating Agent. Upon any payment or distribution of assets or securities
referred to in this Article Ten, the Trustee and the Holders shall be entitled
to rely upon any order or decree made by any court of competent jurisdiction in
which bankruptcy, dissolution, winding up, liquidation or reorganization
proceedings are pending, or upon a certificate of the receiver, trustee in
bankruptcy, liquidating trustee, agent or other similar Person making such
payment or distribution, delivered to the Trustee or to the Holders for the
purpose of ascertaining the Persons entitled to participate in such
distribution, the holders of the Senior Indebtedness and other Indebtedness of
the Company, the amount thereof or payable thereon, the amount or amounts paid
or distributed thereon and all other facts pertinent thereto or to this Article
Ten.

<PAGE>   84


                                       82


                  SECTION 10.08. Trustee's Relation to Senior Indebtedness. (a)
The Trustee and any Paying Agent shall be entitled to all the rights set forth
in this Article Ten with respect to any Senior Indebtedness that may at any time
be held by it in its individual or any other capacity to the same extent as any
other holder of Senior Indebtedness and nothing in this Indenture shall deprive
the Trustee or any Paying Agent of any of its rights as such holder.

                  (b) With respect to the holders of Senior Indebtedness, the
Trustee undertakes to perform or to observe only such of its covenants and
obligations as are specifically set forth in this Article Ten, and no implied
covenants or obligations with respect to the holders of Senior Indebtedness
shall be read into this Indenture against the Trustee. The Trustee shall not be
deemed to owe any fiduciary duty to the holders of Senior Indebtedness (except
as provided in Sections 10.02(c) and 10.03(c) of this Indenture) and shall not
be liable to any such holders if the Trustee shall in good faith mistakenly pay
over or distribute to Holders of Notes or to the Company or to any other person
cash, property or securities to which any holders of Senior Indebtedness shall
be entitled by virtue of this Article Ten or otherwise.

                  SECTION 10.09. Subordination Rights Not Impaired by Acts or
Omissions of the Company or Holders of Senior Indebtedness. No right of any
present or future holders of any Senior Indebtedness to enforce subordination as
provided in this Article Ten will at any time in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any act
or failure to act, in good faith, by any such holder, or by any noncompliance by
the Company with the terms of this Indenture, regardless of any knowledge
thereof that any such holder may have or otherwise be charged with. The
provisions of this Article Ten are intended to be for the benefit of, and shall
be enforceable directly by, the holders of Senior Indebtedness.

                  SECTION 10.10. Holders Authorize Trustee to Effectuate
Subordination of Notes. Each Holder by his acceptance of any Notes authorizes
and expressly directs the Trustee on his behalf to take such action as may be
necessary or appropriate to effectuate the subordination provided in this
Article Ten, and appoints the Trustee his attorney-in-fact for such purposes,
including, in the event of any dissolution, winding up, liquidation or
reorganization of the Company (whether in bankruptcy, insolvency, receivership,
reorganization or similar proceedings or upon an assignment for the benefit of
creditors or otherwise) tending towards liquidation of the property and assets
of the Company, the filing of a claim for the unpaid balance of its Notes in the
form required in those proceedings. If the Trustee does not file a proper claim
or proof of indebtedness in the form required in such proceeding at least 30
days before the expiration of the time to file such claim or claims, each holder
of Senior Indebtedness is hereby authorized to file an appropriate claim for and
on behalf of the Holders.

                  SECTION 10.11.  Not to Prevent Events of Default.  The failure
to make a payment on account of principal of, premium, if any, or interest on
the Notes by reason of

<PAGE>   85


                                       83

any provision of this Article Ten will not be construed as preventing the
occurrence of an Event of Default.

                  SECTION 10.12. Trustee's Compensation Not Prejudiced. Nothing
in this Article Ten will apply to amounts due to the Trustee pursuant to other
sections of this Indenture, including Section 7.07.

                  SECTION 10.13. No Waiver of Subordination Provisions. Without
in any way limiting the generality of Section 10.09, the holders of Senior
Indebtedness may, at any time and from time to time, without the consent of or
notice to the Trustee or the Holders, without incurring responsibility to the
Holders and without impairing or releasing the subordination provided in this
Article Ten or the obligations hereunder of the Holders to the holders of Senior
Indebtedness, do any one or more of the following: (a) change the manner, place
or terms of payment or extend the time of payment of, or renew or alter, Senior
Indebtedness or any instrument evidencing the same or any agreement under which
Senior Indebtedness is outstanding or secured; (b) sell, exchange, release or
otherwise deal with any property pledged, mortgaged or otherwise securing Senior
Indebtedness; (c) release any Person liable in any manner for the collection of
Senior Indebtedness; and (d) exercise or refrain from exercising any rights
against the Company and any other Person.

                  SECTION 10.14. Payments May Be Paid Prior to Dissolution.
Nothing contained in this Article Ten or elsewhere in this Indenture shall
prevent (i) the Company except under the conditions described in Section 10.02
or 10.03, from making payments of principal of, premium, if any, and interest on
the Notes, or from depositing with the Trustee any money for such payments, or
(ii) the application by the Trustee of any money deposited with it for the
purpose of making such payments of principal of, premium, if any, and interest
on the Notes to the Holders entitled thereto unless, at least two Business Days
prior to the date upon which such payment becomes due and payable, the Trustee
shall have received the written notice provided for in Section 10.02(b) of this
Indenture (or there shall have been an acceleration of the Notes prior to such
application) or in Section 10.06 of this Indenture. The Company shall give
prompt written notice to the Trustee of any dissolution, winding up, liquidation
or reorganization of the Company.

                  SECTION 10.15. Trust Moneys Not Subordinated. Notwithstanding
anything contained herein to the contrary, payments from money or the proceeds
of U.S. Government Obligations held in trust under Article Eight by the Trustee
for the payment of principal of, premium, if any, and interest on the Notes
shall not be subordinated to the prior payment of any Senior Indebtedness
(provided that at the time deposited, such deposit did not violate the terms of
any then outstanding Senior Indebtedness), and none of the Holders shall be
obligated to pay over any such amount to any holder of Senior Indebtedness.



<PAGE>   86


                                       84

                                 ARTICLE ELEVEN
                                  MISCELLANEOUS

                  SECTION 11.01. Trust Indenture Act of 1939. Prior to the
effectiveness of the Registration Statement, this Indenture shall incorporate
and be governed by the provisions of the TIA that are required to be part of and
to govern indentures qualified under the TIA. After the effectiveness of the
Registration Statement, this Indenture shall be subject to the provisions of the
TIA that are required to be a part of this Indenture and shall, to the extent
applicable, be governed by such provisions.

                  SECTION 11.02.  Notices.  Any notice or communication shall be
sufficiently given if in writing and delivered in person or mailed by first
class mail addressed as follows:

                  if to the Company:

                           PageMart Wireless, Inc.
                           3333 Lee Parkway
                           Suite 900
                           Dallas, Texas  75219
                           Attention:  President

                  if to the Trustee:

                           United States Trust Company of New York
                           114 West 47th Street
                           New York, New York  10036
                           Attention:  Corporate Trust Department

                  The Company or the Trustee by notice to the other may
designate additional or different addresses for subsequent notices or
communications.

                  Any notice or communication mailed to a Holder shall be mailed
to him at his address as it appears on the Note Register by first class mail and
shall be sufficiently given to him if so mailed within the time prescribed.
Copies of any such communication or notice to a Holder shall also be mailed to
the Trustee and each Agent at the same time.

                  Failure to mail a notice or communication to a Holder or any
defect in it shall not affect its sufficiency with respect to other Holders.
Except for a notice to the Trustee, which is deemed given only when received,
and except as otherwise provided in this Indenture, if a notice or communication
is mailed in the manner provided in this Section 11.02, it is duly given,
whether or not the addressee receives it.

                  Where this Indenture provides for notice in any manner, such
notice may be waived in writing by the Person entitled to receive such notice,
either before or after the

<PAGE>   87


                                       85

event, and such waiver shall be the equivalent of such notice. Waivers of notice
by Holders shall be filed with the Trustee, but such filing shall not be a
condition precedent to the validity of any action taken in reliance upon such
waiver.

                  In case by reason of the suspension of regular mail service or
by reason of any other cause it shall be impracticable to give such notice by
mail, then such notification as shall be made with the approval of the Trustee
shall constitute a sufficient notification for every purpose hereunder.

                  SECTION 11.03. Certificate and Opinion as to Conditions
Precedent. Upon any request or application by the Company to the Trustee to take
any action under this Indenture, the Company shall furnish to the Trustee:

                  (i) an Officers' Certificate stating that, in the opinion of
         the signers, all conditions precedent, if any, provided for in this
         Indenture relating to the proposed action have been complied with; and

                  (ii) an Opinion of Counsel stating that, in the opinion of
         such Counsel, all such conditions precedent have been complied with.

                  SECTION 11.04. Statements Required in Certificate or Opinion.
Each certificate or opinion with respect to compliance with a condition or
covenant provided for in this Indenture shall include:

                  (i) a statement that each person signing such certificate or
         opinion has read such covenant or condition and the definitions herein
         relating thereto;

                  (ii) a brief statement as to the nature and scope of the
         examination or investigation upon which the statement or opinion
         contained in such certificate or opinion is based;

                  (iii) a statement that, in the opinion of each such person, he
         has made such examination or investigation as is necessary to enable
         him to express an informed opinion as to whether or not such covenant
         or condition has been complied with; and

                  (iv) a statement as to whether or not, in the opinion of each
         such person, such condition or covenant has been complied with;
         provided, however, that, with respect to matters of fact, an Opinion of
         Counsel may rely on an Officers' Certificate or certificates of public
         officials.

                  SECTION 11.05.  Rules by Trustee, Paying Agent or Registrar.
The Trustee may make reasonable rules for action by or at a meeting of Holders.
The Paying Agent or Registrar may make reasonable rules for its functions.

<PAGE>   88


                                       86

                  SECTION 11.06. Payment Date Other Than a Business Day. If an
Interest Payment Date, Redemption Date, Stated Maturity or date of maturity of
any Note shall not be a Business Day, then payment of principal of, premium, if
any, or interest on such Note, as the case may be, need not be made on such
date, but may be made on the next succeeding Business Day with the same force
and effect as if made on the Interest Payment Date or Redemption Date, or at the
Stated Maturity or date of maturity of such Note; provided that no interest
shall accrue for the period from and after such Interest Payment Date,
Redemption Date, Stated Maturity or date of maturity, as the case may be.

                  SECTION 11.07. Governing Law. The laws of the State of New
York shall govern this Indenture and the Notes. The Trustee, the Company and the
Holders agree to submit to the jurisdiction of the courts of the State of New
York in any action or proceeding arising out of or relating to this Indenture or
the Notes.

                  SECTION 11.08. No Adverse Interpretation of Other Agreements.
This Indenture may not be used to interpret another indenture, loan or debt
agreement of the Company or any Subsidiary of the Company. Any such indenture,
loan or debt agreement may not be used to interpret this Indenture.

                  SECTION 11.09. No Recourse Against Others. No recourse for the
payment of the principal of, premium, if any, or interest on any of the Notes,
or for any claim based thereon or otherwise in respect thereof, and no recourse
under or upon any obligation, covenant or agreement of the Company contained in
this Indenture, or in any of the Notes, or because of the creation of any
Indebtedness represented thereby, shall be had against any incorporator or
against any past, present or future partner, shareholder, other equityholder,
officer, director, employee or controlling person, as such, of the Company or of
any successor Person, either directly or through the Company or any successor
Person, whether by virtue of any constitution, statute or rule of law, or by the
enforcement of any assessment or penalty or otherwise; it being expressly
understood that all such liability is hereby expressly waived and released as a
condition of, and as a consideration for, the execution of this Indenture and
the issue of the Notes.

                  SECTION 11.10.  Successors.  All agreements of the Company in
this Indenture and the Notes shall bind its successors. All agreements of the
Trustee in this Indenture shall bind its successor.

                  SECTION 11.11.  Duplicate Originals.  The parties may sign any
number of copies of this Indenture. Each signed copy shall be an original, but
all of them together represent the same agreement.

                  SECTION 11.12. Separability. In case any provision in this
Indenture or in the Notes shall be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

<PAGE>   89


                                       87

                  SECTION 11.13. Table of Contents, Headings, Etc. The Table of
Contents, Cross-Reference Table and headings of the Articles and Sections of
this Indenture have been inserted for convenience of reference only, are not to
be considered a part hereof and shall in no way modify or restrict any of the
terms and provisions hereof.

                                   SIGNATURES

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


                                           PAGEMART WIRELESS, INC.


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



                                           UNITED STATES TRUST COMPANY
                                                 OF NEW YORK


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

<PAGE>   90



                                                                       EXHIBIT A


                                 [FACE OF NOTE]

                             PAGEMART WIRELESS, INC.

               11 1/4% Senior Subordinated Discount Note Due 2008

                                                [CUSIP] [CINS] [ISIN] __________


No.                                                                   $_________

                  The following information is supplied for purposes of Sections
1273 and 1275 of the Internal Revenue Code:

Issue Date: January 28, 1998

Yield to maturity for period from Issue Date to February 1, 2008: 11 1/4%,
compounded semi-annually on February 1 and August 1 commencing August 1, 1998
(computed without giving effect to the additional payments of interest in the
event the issuer fails to commence the exchange offer or cause the registration
statement to be declared effective, each as described on the reverse hereof)

Original issue discount under Section 1273 of the Internal Revenue Code (for
each $1,000 principal amount): $984.49

Issue Price (for each $1,000 principal amount): $578.01


                  PAGEMART WIRELESS, INC., a Delaware corporation (the
"Company", which term includes any successor under the Indenture hereinafter
referred to), for value received, promises to pay to____________, or its
registered assigns, the principal sum of _____________($_______) on February 1,
2008.

                  Interest Payment Dates:  February 1 and August 1, commencing
August 1, 2003.

                  Regular Record Dates: January 15 and July 15.

                Reference is hereby made to the further provisions of this Note
set forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

<PAGE>   91


                                       A-2

                IN WITNESS WHEREOF, the Company has caused this Note to be
signed manually or by facsimile by its duly authorized officers.


Date:  January 28, 1998                    PAGEMART WIRELESS, INC.


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

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



                (Form of Trustee's Certificate of Authentication)

This is one of the 11 1/4% Senior Subordinated Discount Notes due 2008 described
in the within-mentioned Indenture.


                                           _______________, as Trustee



                                           By:
                                              ----------------------------------
                                              Authorized Signatory

<PAGE>   92


                                       A-3

                             [REVERSE SIDE OF NOTE]

                             PAGEMART WIRELESS, INC.

               11 1/4% Senior Subordinated Discount Note due 2008



1.  Principal and Interest.

                  The Company will pay the principal of this Note on February 1,
2008.

                  The Company promises to pay interest on the principal amount
of this Note on each Interest Payment Date, as set forth below, at the rate per
annum shown above.

                  Interest will be payable semiannually (to the holders of
record of the Notes at the close of business on the January 15 or July 15
immediately preceding the Interest Payment Date) on each Interest Payment Date,
commencing August 1, 2003; provided that no interest shall accrue on the
principal amount of this Note prior to February 1, 2003 and no interest shall be
paid on this Note prior to August 1, 2003, except as provided in the next
paragraph.

                  If an exchange offer registered under the Securities Act is
not consummated, or a shelf registration statement under the Securities Act with
respect to resales of the Notes is not declared effective by the Commission, on
or before July 28, 1998 in accordance with the terms of the Registration Rights
Agreement dated January 28, 1998 between the Company and Morgan Stanley & Co.
Incorporated, interest on the Notes (in addition to the accrual of original
discount during the period ending February 1, 2003 and in addition to the
interest otherwise due on the Notes after such date) will accrue, at an annual
rate of 0.5% of Accreted Value on the preceding Semiannual Accrual Date from
July 28, 1998, payable in cash semiannually, in arrears, on each February 1 and
August 1, commencing February 1, 1999. The Holder of this Note is entitled to
the benefits of such Registration Rights Agreement.

                  From and after February 1, 2003, interest on the Notes will
accrue from the most recent date to which interest has been paid or, if no
interest has been paid, from February 1, 2003; provided that, if there is no
existing default in the payment of interest and this Note is authenticated
between a Regular Record Date referred to on the face hereof and the next
succeeding Interest Payment Date, interest shall accrue from such Interest
Payment Date. Interest will be computed on the basis of a 360-day year of twelve
30-day months.

                  The Company shall pay interest on overdue principal and
premium, if any, and interest on overdue installments of interest, to the extent
lawful, at a rate per annum that is 2% in excess of the rate otherwise payable.

<PAGE>   93


                                       A-4


2.  Method of Payment.

                  The Company will pay interest (except defaulted interest) on
the principal amount of the Notes as provided above on each February 1 and
August 1 to the persons who are Holders (as reflected in the Note Register at
the close of business on such January 15 and July 15 immediately preceding the
Interest Payment Date), in each case, even if the Note is cancelled on
registration of transfer or registration of exchange after such record date;
provided that, with respect to the payment of principal, the Company will make
payment to the Holder that surrenders this Note to a Paying Agent on or after
February 1, 2008.

                  The Company will pay principal, premium, if any, and as
provided above, interest in money of the United States that at the time of
payment is legal tender for payment of public and private debts. However, the
Company may pay principal, premium, if any, and interest by its check payable in
such money. It may mail an interest check to a Holder's registered address (as
reflected in the Note Register). If a payment date is a date other than a
Business Day at a place of payment, payment may be made at that place on the
next succeeding day that is a Business Day and no interest shall accrue for the
intervening period.

3.  Paying Agent and Registrar.

                  Initially, the Trustee will act as authenticating agent,
Paying Agent and Registrar. The Company may change any authenticating agent,
Paying Agent or Registrar without notice. The Company, any Subsidiary or any
Affiliate of any of them may act as Paying Agent, Registrar or co-Registrar.

4.  Indenture; Limitations.

                  The Company issued the Notes under an Indenture dated as of
January 28, 1998 (the "Indenture"), between the Company and United States Trust
Company of New York, as trustee (the "Trustee"). Capitalized terms herein are
used as defined in the Indenture unless otherwise indicated. The terms of the
Notes include those stated in the Indenture and those made part of the Indenture
by reference to the Trust Indenture Act. The Notes are subject to all such
terms, and Holders are referred to the Indenture and the Trust Indenture Act for
a statement of all such terms. To the extent permitted by applicable law, in the
event of any inconsistency between the terms of this Note and the terms of the
Indenture, the terms of the Indenture shall control.

                  The Notes are general unsecured obligations of the Company.
The Company may, subject to Article Four of the Indenture, issue additional
Notes under the Indenture.


<PAGE>   94


                                       A-5

5.  Redemption.

                  The Notes will be redeemable, at the Company's option, in
whole or in part, at any time on or after February 1, 2003 and prior to
maturity, upon not less than 30 nor more than 60 days' prior notice mailed by
first-class mail to each Holder's last address as it appears in the Note
Register, at the following Redemption Prices (expressed in percentages of their
principal amount at maturity), plus accrued and unpaid interest, if any, to the
Redemption Date (subject to the right of Holders of record on the relevant
Regular Record Date that is on or prior to the Redemption Date to receive
interest due on an Interest Payment Date) if redeemed during the 12-month period
commencing February 1 of the applicable years set forth below:

<TABLE>
<CAPTION>
                                                       Redemption
         Year                                            Price
         ----                                         -----------
         <S>                                          <C>
         2003                                           105.625%
         2004                                           103.750
         2005                                           101.875
         2006 and thereafter                            100.000
</TABLE>

                  In addition, prior to February 1, 2001, the Company may redeem
up to 35% of the principal amount of the Notes with the proceeds of one or more
sales of Capital Stock (other than Redeemable Stock) of the Company, at any time
or from time to time in part, at a Redemption Price equal to 111.250% of their
Accreted Value on the Redemption Date provided that at least $280.8 million
aggregate principal amount at maturity of Notes remains outstanding after each
of such redemption.

                  Notice of any redemption will be mailed at least 30 days but
not more than 60 days before the Redemption Date to each Holder of Notes to be
redeemed at his last address as it appears in the Note Register. Notes in
original denominations larger than $1,000 may be redeemed in part. On and after
the Redemption Date, interest ceases to accrue on Notes or portions of Notes
called for redemption, unless the Company defaults in the payment of the
Redemption Price.

6. Repurchase upon Change in Control.

                  The Company shall commence, within 30 days of the occurrence
of a Change of Control, and consummate an Offer to Purchase for all Notes then
outstanding, at a purchase price equal to 101% of the Accreted Value thereof on
the relevant Payment Date, plus accrued interest (if any) to the Payment Date.

                  A notice of such Change of Control will be mailed within 30
days after any Change of Control occurs to each Holder at his last address as it
appears in the Note Register. Notes in original denominations larger than $1,000
may be sold to the Company in part. On and after the Change of Control Payment
Date, interest ceases to accrue on Notes or portions

<PAGE>   95


                                       A-6

of Notes surrendered for purchase by the Company, unless the Company defaults in
the payment of the Change of Control Payment.

7.  Denominations; Transfer; Exchange.

                  The Notes are in registered form without coupons in
denominations of $1,000 of principal amount at maturity and multiples of $1,000
in excess thereof. A Holder may register the transfer or exchange of Notes in
accordance with the Indenture. The Registrar may require a Holder, among other
things, to furnish appropriate endorsements and transfer documents and to pay
any taxes and fees required by law or permitted by the Indenture. The Registrar
need not register the transfer or exchange of any Notes selected for redemption.
Also, it need not register the transfer or exchange of any Notes for a period of
15 days before a selection of Notes to be redeemed is made.

8.  Persons Deemed Owners.

                  A Holder shall be treated as the owner of a Note for all
purposes.

9.  Unclaimed Money.

                  If money for the payment of principal, premium, if any, or
interest remains unclaimed for two years, the Trustee and the Paying Agent will
pay the money back to the Company at its request. After that, Holders entitled
to the money must look to the Company for payment, unless an abandoned property
law designates another Person, and all liability of the Trustee and such Paying
Agent with respect to such money shall cease.

10. Discharge Prior to Redemption or Maturity.

                  If the Company deposits with the Trustee money or U.S.
Government Obligations sufficient to pay the then outstanding principal of,
premium, if any, and accrued interest on the Notes (a) to redemption or
maturity, the Company will be discharged from the Indenture and the Notes,
except in certain circumstances for certain sections thereof, and (b) to the
Stated Maturity, the Company will be discharged from certain covenants set forth
in the Indenture.

<PAGE>   96


                                       A-7


11.  Amendment; Supplement; Waiver.

                  Subject to certain exceptions, the Indenture or the Notes may
be amended or supplemented with the consent of the Holders of at least a
majority in principal amount of the Notes then outstanding, and any existing
default or compliance with any provision may be waived with the consent of the
Holders of at least a majority in principal amount of the Notes then
outstanding. Without notice to or the consent of any Holder, the parties thereto
may amend or supplement the Indenture or the Notes to, among other things, cure
any ambiguity, defect or inconsistency and make any change that does not
materially and adversely affect the rights of any Holder.

12.  Restrictive Covenants.

                  The Indenture imposes certain limitations on the ability of
the Company and its Restricted Subsidiaries, among other things, to Incur
additional Indebtedness, make Restricted Payments, use the proceeds from Asset
Sales, engage in transactions with Affiliates or merge, consolidate or transfer
substantially all of its assets. Within 45 days after the end of each fiscal
quarter (90 days after the end of the last fiscal quarter of each year), the
Company must report to the Trustee on compliance with such limitations.

13.  Successor Persons.

                  When a successor person or other entity assumes all the
obligations of its predecessor under the Notes and the Indenture, the
predecessor person will be released from those obligations.

14.  Defaults and Remedies.

                  The following events constitute "Events of Default" under the
Indenture: (a) default in the payment of the principal of (or premium, if any,
on) any Note when the same becomes due and payable at maturity, upon
acceleration, redemption or otherwise, whether or not such payment is prohibited
by Section Ten; (b) default in the payment of interest on any Note when the same
becomes due and payable, and such default continues for a period of 30 days
whether or not such payment is prohibited by Section Ten; (c) default in the
performance of or breaches the provisions of the Indenture applicable to
mergers, consolidations and transfers of all or substantially all of the assets
of the Company or fails to make or consummate an Offer to Purchase in accordance
with Section 4.11 or Section 4.12 of the Indenture; (d) the Company defaults in
the performance of or breaches any other covenant or agreement of the Company in
the Indenture or under the Notes (other than a default specified in clause (a),
(b) or (c) above) and such default or breach continues for a period of 30
consecutive days after written notice by the Trustee or the Holders of 25% or
more in

<PAGE>   97


                                       A-8

aggregate principal amount of the Notes; (e) there occurs with respect to any
issue or issues of Indebtedness of the Company or any Significant Subsidiary
having an outstanding principal amount of $10 million or more in the aggregate
for all such issues of all such Persons, whether such Indebtedness now exists or
shall hereafter be created, (I) an event of default that has caused the holder
thereof to declare such Indebtedness to be due and payable prior to its Stated
Maturity and such Indebtedness has not been discharged in full or such
acceleration has not been rescinded or annulled within 30 days of such
acceleration and/or (II) the failure to make a principal payment at the final
(but not any interim) fixed maturity and such defaulted payment shall not have
been made, waived or extended within 30 days of such payment default; (f) any
final judgment or order (not covered by insurance) for the payment of money in
excess of $10 million in the aggregate for all such final judgments or orders
against all such Persons (treating any deductibles, self-insurance or retention
as not so covered) shall be rendered against the Company or any Significant
Subsidiary and shall not be paid or discharged, and there shall be any period of
30 consecutive days following entry of the final judgment or order that causes
the aggregate amount for all such final judgments or orders outstanding and not
paid or discharged against all such Persons to exceed $10 million during which a
stay of enforcement of such final judgment or order, by reason of a pending
appeal or otherwise, shall not be in effect; (g) a court having jurisdiction in
the premises enters a decree or order for (A) relief in respect of the Company
or any Significant Subsidiary in an involuntary case under any applicable
bankruptcy, insolvency or other similar law now or hereafter in effect, (B)
appointment of a receiver, liquidator, assignee, custodian, trustee,
sequestrator or similar official of the Company or any Significant Subsidiary or
for all or substantially all of the property and assets of the Company or any
Significant Subsidiary or (C) the winding up or liquidation of the affairs of
the Company or any Significant Subsidiary and, in each case, such decree or
order shall remain unstayed and in effect for a period of 60 consecutive days;
or (h) the Company or any Significant Subsidiary (A) commences a voluntary case
under any applicable bankruptcy, insolvency or other similar law now or
hereafter in effect, or consents to the entry of an order for relief in an
involuntary case under any such law, (B) consents to the appointment of or
taking possession by a receiver, liquidator, assignee, custodian, trustee,
sequestrator or similar official of the Company or any Significant Subsidiary or
for all or substantially all of the property and assets of the Company or any
Significant Subsidiary or (C) effects any general assignment for the benefit of
creditors.

                  If an Event of Default, as defined in the Indenture, occurs
and is continuing, the Trustee or the Holders of at least 25% in principal
amount of the Notes may declare all the Notes to be due and payable. Upon a
declaration of acceleration (the "Acceleration Notice"), such Accreted Value of,
premium, if any, and accrued interest shall be immediately due and payable;
provided, however, that if there are any amounts outstanding under the Credit
Agreement, such declaration shall not become effective until the earlier of (i)
an acceleration of the Indebtedness under the Credit Agreement and (ii) five
Business Days after receipt by the Company and the Bank Agent of such
Acceleration Notice. If a bankruptcy or insolvency default with respect to the
Company or any Restricted Subsidiary occurs and is

<PAGE>   98


                                       A-9

continuing, the Notes automatically become due and payable. Holders may not
enforce the Indenture or the Notes except as provided in the Indenture. The
Trustee may require indemnity satisfactory to it before it enforces the
Indenture or the Notes. Subject to certain limitations, Holders of at least a
majority in principal amount of the Notes then outstanding may direct the
Trustee in its exercise of any trust or power.


15.  Subordination

                  The payment of the Notes will, to the extent set forth in the
Indenture, be subordinated in right of payment to the prior payment in full, in
cash or cash equivalents, of all Senior Indebtedness.

16.  Trustee Dealings with Company.

                  The Trustee under the Indenture, in its individual or any
other capacity, may make loans to, accept deposits from and perform services for
the Company or its Affiliates and may otherwise deal with the Company or its
Affiliates as if it were not the Trustee.

17.  No Recourse Against Others.

                  No incorporator or any past, present or future partner,
shareholder, other equity holder, officer, director, employee or controlling
person as such, of the Company or of any successor Person shall have any
liability for any obligations of the Company under the Notes or the Indenture or
for any claim based on, in respect of or by reason of, such obligations or their
creation. Each Holder by accepting a Note waives and releases all such
liability. The waiver and release are part of the consideration for the issuance
of the Notes.

18.  Authentication.

                  This Note shall not be valid until the Trustee or
authenticating agent signs the certificate of authentication on the other side
of this Note.

19.  Abbreviations.

                  Customary abbreviations may be used in the name of a Holder or
an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the
entireties), JT TEN (= joint tenants with right of survivorship and not as
tenants in common), CUST (= Custodian) and U/G/M/A (= Uniform Gifts to Minors
Act).

<PAGE>   99


                                      A-10

                  The Company will furnish to any Holder upon written request
and without charge a copy of the Indenture. Requests may be made to PageMart
Wireless, Inc., 3333 Lee Parkway, Suite 900, Dallas, Texas 75219, Attention:
President.

<PAGE>   100
                                      A-11

                            [FORM OF TRANSFER NOTICE]

                  FOR VALUE RECEIVED the undersigned registered holder hereby
sell(s), assign(s) and transfer(s) unto

Insert Taxpayer Identification No.

--------------------------------------------------------------------------------
Please print or typewrite name and address including zip code of assignee

--------------------------------------------------------------------------------
the within Note and all rights thereunder, hereby irrevocably constituting and
appointing ____________________________________attorney to transfer said Note on
the books of the Company with full power of substitution in the premises.


                     [THE FOLLOWING PROVISION TO BE INCLUDED
                     ON ALL NOTES OTHER THAN EXCHANGE NOTES,
                      UNLEGENDED OFFSHORE GLOBAL NOTES AND
                       UNLEGENDED OFFSHORE PHYSICAL NOTES]

                  In connection with any transfer of this Note occurring prior
to the date which is the earlier of (i) the date the shelf registration
statement is declared effective or (ii) the end of the period referred to in
Rule 144(k) under the Securities Act, the undersigned confirms that without
utilizing any general solicitation or general advertising that:

                                   [Check One]

[ ] (a)  this Note is being transferred in compliance with the exemption
         from registration under the Securities Act of 1933, as amended,
         provided by Rule 144A thereunder.

                                       or

[ ] (b)  this Note is being transferred other than in accordance with (a)
         above and documents are being furnished which comply with the
         conditions of transfer set forth in this Note and the Indenture.

<PAGE>   101


                                      A-12

If none of the foregoing boxes is checked, the Trustee or other Registrar shall
not be obligated to register this Note in the name of any Person other than the
Holder hereof unless and until the conditions to any such transfer of
registration set forth herein and in Section 2.08 of the Indenture shall have
been satisfied.

Date:
     ---------------                        ------------------------------------
                                            NOTICE: The signature to this
                                            assignment must correspond with the
                                            name as written upon the face of the
                                            within-mentioned instrument in every
                                            particular, without alteration or
                                            any change whatsoever.



TO BE COMPLETED BY PURCHASER IF (a) ABOVE IS CHECKED.

                  The undersigned represents and warrants that it is purchasing
this Note for its own account or an account with respect to which it exercises
sole investment discretion and that it and any such account is a "qualified
institutional buyer" within the meaning of Rule 144A under the Securities Act of
1933, as amended, and is aware that the sale to it is being made in reliance on
Rule 144A and acknowledges that it has received such information regarding the
Company as the undersigned has requested pursuant to Rule 144A or has determined
not to request such information and that it is aware that the transferor is
relying upon the undersigned's foregoing representations in order to claim the
exemption from registration provided by Rule 144A.

Dated:
      ---------------           ------------------------------------------------
                                NOTICE:  To be executed by an executive officer

<PAGE>   102


                                      A-13


                       OPTION OF HOLDER TO ELECT PURCHASE


                  If you wish to have this Note purchased by the Company
pursuant to Section 4.11 or Section 4.12 of the Indenture, check the Box: |_|

                  If you wish to have a portion of this Note purchased by the
Company pursuant to Section 4.11 or Section 4.12 of the Indenture, state the
amount (in principal amount at maturity): $___________________.

Date:
     -----------------------

Your Signature:
               -----------------------------------------------------------------
              (Sign exactly as your name appears on the other side of this Note)

Signature Guarantee:
                      ------------------------------

<PAGE>   103



                                                                       EXHIBIT B


                               Form of Certificate

                                                              ______________,___


United States Trust Company of New York
114 West 47th Street
New York, New York  10036
Attention:  Corporate Trust Department


                         Re:   PageMart Wireless, Inc. (the "Company")
                               11 1/4% Senior Subordinated Discount Notes
                               due 2008 (the "Notes")

Dear Sirs:

                This letter relates to U.S. $ principal amount at maturity of
Notes represented by a Note (the "Legended Note") which bears a legend outlining
restrictions upon transfer of such Legended Note. Pursuant to Section 2.01 of
the Indenture (the "Indenture") dated as of January 28, 1998 relating to the
Notes, we hereby certify that we are (or we will hold such securities on behalf
of) a person outside the United States to whom the Notes could be transferred in
accordance with Rule 904 of Regulation S promulgated under the U.S. Securities
Act of 1933, as amended. Accordingly, you are hereby requested to exchange the
legended certificate for an unlegended certificate representing an identical
principal amount at maturity of Notes, all in the manner provided for in the
Indenture.

                You and the Company are entitled to rely upon this letter and
are irrevocably authorized to produce this letter or a copy hereof to any
interested party in any administrative or legal proceedings or official inquiry
with respect to the matters covered hereby. Terms used in this certificate have
the meanings set forth in Regulation S.

                                                     Very truly yours,

                                         [Name of Holder]



                                         By:
                                            ------------------------------------
                                            Authorized Signature

<PAGE>   104



                                                                       EXHIBIT C



                            Form of Certificate to Be
                          Delivered in Connection with
                    Transfers to Non-QIB Accredited Investors


                                             ____________,___




United States Trust Company of New York
114 West 47th Street
New York, New York  10036
Attention:  Corporate Trust Department


                  Re:  PageMart Wireless, Inc. (the "Company")
                        11 1/4%  Senior Subordinated Discount Notes due 2008
                        (the "Notes")



Dear Sirs:

                In connection with our proposed purchase of $___________________
aggregate principal amount at maturity of the Notes, we confirm that:

                1. We understand that any subsequent transfer of the Notes is
subject to certain restrictions and conditions set forth in the Indenture dated
as of January 28, 1998, relating to the Notes (the "Indenture") and the
undersigned agrees to be bound by, and not to resell, pledge or otherwise
transfer the Notes except in compliance with, such restrictions and conditions
and the Securities Act of 1933, as amended (the "Securities Act").

                2. We understand that the offer and sale of the Notes have not
been registered under the Notes Act, and that the Notes may not be offered or
sold except as permitted in the following sentence. We agree, on our own behalf
and on behalf of any accounts for which we are acting as hereinafter stated,
that if we should sell any Notes, we will do so only (A) to the Company or any
subsidiary thereof, (B) in accordance with Rule 144A under the Securities Act to
a "qualified institutional buyer" (as defined therein), (C) to an institutional
"accredited investor" (as defined below) that, prior to such transfer, furnishes
(or has furnished on its behalf by a U.S. broker-dealer) to you and to the
Company a signed letter

<PAGE>   105


                                       C-2

substantially in the form of this letter, (D) outside the United States in
accordance with Rule 904 of Regulation S under the Securities Act, (E) pursuant
to the exemption from registration provided by Rule 144 under the Securities
Act, or (F) pursuant to an effective registration statement under the Securities
Act, and we further agree to provide to any person purchasing any of the Notes
from us a notice advising such purchaser that resales of the Notes are
restricted as stated herein.

                3. We understand that, on any proposed resale of any Notes, we
will be required to furnish to you and the Company such certifications, legal
opinions and other information as you and the Company may reasonably require to
confirm that the proposed sale complies with the foregoing restrictions. We
further understand that the Notes purchased by us will bear a legend to the
foregoing effect.

                4. We are an institutional "accredited investor" (as defined in
Rule 501(a)(1), (2), (3) or (7) of Regulation D under the Securities Act) and
have such knowledge and experience in financial and business matters as to be
capable of evaluating the merits and risks of our investment in the Notes, and
we and any accounts for which we are acting are each able to bear the economic
risk of our or its investment.

                5. We are acquiring the Notes purchased by us for our own
account or for one or more accounts (each of which is an institutional
"accredited investor") as to each of which we exercise sole investment
discretion.

                You and the Company are entitled to rely upon this letter and
are irrevocably authorized to produce this letter or a copy hereof to any
interested party in any administrative or legal proceedings or official inquiry
with respect to the matters covered hereby.

                                       Very truly yours,

                                       [Name of Transferee]


                                       By:
                                          --------------------------------
                                          Authorized Signature

<PAGE>   106



                                                                       EXHIBIT D



                       Form of Certificate to Be Delivered
                          in Connection with Transfers
                            Pursuant to Regulation S


                                          ____________,___




United States Trust Company of New York
114 West 47th Street
New York, New York  10036
Attention:  Corporate Trust Department


                         Re:      PageMart Wireless, Inc. (the "Company")
                                  11 1/4% Senior Subordinated Discount Notes
                                  due 2008 (the "Notes")


Dear Sirs:

                In connection with our proposed sale of U.S.$ aggregate
principal amount at maturity of the Notes, we confirm that such sale has been
effected pursuant to and in accordance with Regulation S under the Securities
Act of 1933, as amended, and, accordingly, we represent that:

                (1)  the offer of the Notes was not made to a person in the
United States;

                (2) at the time the buy order was originated, the transferee was
outside the United States or we and any person acting on our behalf reasonably
believed that the transferee was outside the United States;

                (3) no directed selling efforts have been made by us in the
United States in contravention of the requirements of Rule 903(b) or Rule 904(b)
of Regulation S, as applicable; and

                (4) the transaction is not part of a plan or scheme to evade the
registration requirements of the U.S. Securities Act of 1933.

<PAGE>   107


                                       D-2


                You and the Company are entitled to rely upon this letter and
are irrevocably authorized to produce this letter or a copy hereof to any
interested party in any administrative or legal proceedings or official inquiry
with respect to the matters covered hereby. Terms used in this certificate have
the meanings set forth in Regulation S.

                                       Very truly yours,

                                       [Name of Transferor]


                                       By:
                                          --------------------------------------
                                          Authorized Signature



<PAGE>   108



                                TABLE OF CONTENTS
<TABLE>
<CAPTION>
                                                                                                               Page
<S>                                                                                                            <C>

    RECITALS OF THE COMPANY.....................................................................................  1

                                   ARTICLE ONE
                   DEFINITIONS AND INCORPORATION BY REFERENCE

    SECTION 1.01.  Definitions..................................................................................  1
    SECTION 1.02.  Incorporation by Reference of Trust Indenture Act............................................ 21
    SECTION 1.03.  Rules of Construction........................................................................ 22

                                   ARTICLE TWO
                                    THE NOTES

    SECTION 2.01.  Form and Dating.............................................................................. 22
    SECTION 2.02.  Restrictive Legends.......................................................................... 24
    SECTION 2.03.  Execution, Authentication and Denominations.................................................. 26
    SECTION 2.04.  Registrar and Paying Agent................................................................... 26
    SECTION 2.05.  Paying Agent to Hold Money in Trust.......................................................... 27
    SECTION 2.06.  Transfer and Exchange........................................................................ 28
    SECTION 2.07.  Book-Entry Provisions for Global Notes....................................................... 29
    SECTION 2.08.  Special Transfer Provisions.................................................................. 31
    SECTION 2.09.  Replacement Notes............................................................................ 33
    SECTION 2.10.  Outstanding Notes............................................................................ 34
    SECTION 2.11.  Temporary Notes.............................................................................. 35
    SECTION 2.12.  Cancellation................................................................................. 35
    SECTION 2.13.  CUSIP Numbers................................................................................ 35
    SECTION 2.14.  Defaulted Interest........................................................................... 36
    SECTION 2.15.  Issuance of Additional Notes................................................................. 36

                                  ARTICLE THREE
                                   REDEMPTION

    SECTION 3.01.  Right of Redemption.......................................................................... 36
    SECTION 3.02.  Notices to Trustee........................................................................... 37
    SECTION 3.03.  Selection of Notes to Be Redeemed............................................................ 37
    SECTION 3.04.  Notice of Redemption......................................................................... 37
    SECTION 3.05.  Effect of Notice of Redemption............................................................... 38
    SECTION 3.06.  Deposit of Redemption Price.................................................................. 38
    SECTION 3.07.  Payment of Notes Called for Redemption....................................................... 39
</TABLE>

--------
 Note:          The Table of Contents shall not for any purposes be deemed to be
                a part of the Indenture.

<PAGE>   109


                                       ii
<TABLE>
<S>                                                                                                            <C>
    SECTION 3.08.  Notes Redeemed in Part....................................................................... 39

                                  ARTICLE FOUR
                                    COVENANTS

    SECTION 4.01.  Payment of Notes............................................................................. 39
    SECTION 4.02.  Maintenance of Office or Agency.............................................................. 39
    SECTION 4.03.  Limitation on Indebtedness................................................................... 40
    SECTION 4.04.  Limitation on Senior Subordinated Indebtedness............................................... 43
    SECTION 4.05.  Limitation on Liens.......................................................................... 44
    SECTION 4.06.  Limitation on Restricted Payments............................................................ 44
    SECTION 4.07.  Limitation on Dividend and Other Payment Restrictions Affecting
                           Restricted Subsidiaries.............................................................. 48
    SECTION 4.08.  Limitation on the Issuance and Sale of Capital Stock of Restricted
                           Subsidiaries......................................................................... 49
    SECTION 4.09.  Limitation on Issuances of Guarantees by Restricted Subsidiaries............................. 49
    SECTION 4.10.  Limitation on Transactions with Shareholders and Affiliates.................................. 50
    SECTION 4.11.  Limitation on Asset Sales.................................................................... 51
    SECTION 4.12.  Repurchase of Notes upon a Change of Control................................................. 52
    SECTION 4.13.  Existence.................................................................................... 52
    SECTION 4.14.  Payment of Taxes and Other Claims............................................................ 53
    SECTION 4.15.  Maintenance of Properties and Insurance...................................................... 53
    SECTION 4.16.  Notice of Defaults........................................................................... 53
    SECTION 4.17.  Compliance Certificates...................................................................... 54
    SECTION 4.18.  Commission Reports and Reports to Holders.................................................... 54
    SECTION 4.19.  Waiver of Stay, Extension or Usury Laws...................................................... 55

                                  ARTICLE FIVE
                              SUCCESSOR CORPORATION

    SECTION 5.01.  When Company May Merge, Etc.................................................................. 55
    SECTION 5.02.  Successor Substituted........................................................................ 56

                                   ARTICLE SIX
                              DEFAULT AND REMEDIES

    SECTION 6.01.  Events of Default............................................................................ 56
    SECTION 6.02.  Acceleration................................................................................. 58
    SECTION 6.03.  Other Remedies............................................................................... 59
    SECTION 6.04.  Waiver of Past Defaults...................................................................... 59
    SECTION 6.05.  Control by Majority.......................................................................... 59
    SECTION 6.06.  Limitation on Suits.......................................................................... 60
</TABLE>

<PAGE>   110


                                       iii
<TABLE>
<S>                                                                                                            <C>
    SECTION 6.07.  Rights of Holders to Receive Payment......................................................... 60
    SECTION 6.08.  Collection Suit by Trustee................................................................... 60
    SECTION 6.09.  Trustee May File Proofs of Claim............................................................. 61
    SECTION 6.10.  Priorities................................................................................... 61
    SECTION 6.11.  Undertaking for Costs........................................................................ 62
    SECTION 6.12.  Restoration of Rights and Remedies........................................................... 62
    SECTION 6.13.  Rights and Remedies Cumulative............................................................... 62
    SECTION 6.14.  Delay or Omission Not Waiver................................................................. 62

                                  ARTICLE SEVEN
                                     TRUSTEE

    SECTION 7.01.  General ..................................................................................... 63
    SECTION 7.02.  Certain Rights of Trustee.................................................................... 63
    SECTION 7.03.  Individual Rights of Trustee................................................................. 64
    SECTION 7.04.  Trustee's Disclaimer......................................................................... 64
    SECTION 7.05.  Notice of Default............................................................................ 64
    SECTION 7.06.  Reports by Trustee to Holders................................................................ 65
    SECTION 7.07.  Compensation and Indemnity................................................................... 65
    SECTION 7.08.  Replacement of Trustee....................................................................... 65
    SECTION 7.09.  Successor Trustee by Merger, Etc............................................................. 66
    SECTION 7.10.  Eligibility.................................................................................. 66
    SECTION 7.11.  Money Held in Trust.......................................................................... 67
    SECTION 7.12.  Withholding Taxes............................................................................ 67

                                  ARTICLE EIGHT
                             DISCHARGE OF INDENTURE

    SECTION 8.01.  Termination of Company's Obligations......................................................... 67
    SECTION 8.02.  Defeasance and Discharge of Indenture........................................................ 68
    SECTION 8.03.  Defeasance of Certain Obligations............................................................ 70
    SECTION 8.04.  Application of Trust Money................................................................... 72
    SECTION 8.05.  Repayment to Company......................................................................... 73
    SECTION 8.06.  Reinstatement................................................................................ 73

                                  ARTICLE NINE
                       AMENDMENTS, SUPPLEMENTS AND WAIVERS

    SECTION 9.01.  Without Consent of Holders................................................................... 73
    SECTION 9.02.  With Consent of Holders...................................................................... 74
    SECTION 9.03.  Revocation and Effect of Consent............................................................. 75
    SECTION 9.04.  Notation on or Exchange of Notes............................................................. 76
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                                       iv
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<S>                                                                                                            <C>
    SECTION 9.05.  Trustee to Sign Amendments, Etc.............................................................. 76
    SECTION 9.06.  Conformity with Trust Indenture Act.......................................................... 76

                                   ARTICLE TEN
                             SUBORDINATION OF NOTES

    SECTION 10.01.  Notes Subordinated to Senior Indebtedness................................................... 76
    SECTION 10.02.  No Payment on Notes in Certain Circumstances................................................ 76
    SECTION 10.03.  Payment over Proceeds upon Dissolution, Etc................................................. 78
    SECTION 10.04.  Subrogation................................................................................. 79
    SECTION 10.05.  Obligations of Company Unconditional........................................................ 80
    SECTION 10.06.  Notice to Trustee........................................................................... 80
    SECTION 10.07.  Reliance on Judicial Order or Certificate of Liquidating Agent.............................. 81
    SECTION 10.08.  Trustee's Relation to Senior Indebtedness................................................... 82
    SECTION 10.09.  Subordination Rights Not Impaired by Acts or Omissions of the
                           Company or Holders of Senior Indebtedness............................................ 82
    SECTION 10.10.  Holders Authorize Trustee to Effectuate Subordination of Notes.............................. 82
    SECTION 10.11.  Not to Prevent Events of Default............................................................ 82
    SECTION 10.12.  Trustee's Compensation Not Prejudiced....................................................... 83
    SECTION 10.13.  No Waiver of Subordination Provisions....................................................... 83
    SECTION 10.14.  Payments May Be Paid Prior to Dissolution................................................... 83
    SECTION 10.15.  Trust Moneys Not Subordinated............................................................... 83

                                 ARTICLE ELEVEN
                                  MISCELLANEOUS

    SECTION 11.01.  Trust Indenture Act of 1939................................................................. 84
    SECTION 11.02.  Notices..................................................................................... 84
    SECTION 11.03.  Certificate and Opinion as to Conditions Precedent.......................................... 85
    SECTION 11.04.  Statements Required in Certificate or Opinion............................................... 85
    SECTION 11.05.  Rules by Trustee, Paying Agent or Registrar................................................. 85
    SECTION 11.06.  Payment Date Other Than a Business Day...................................................... 86
    SECTION 11.07.  Governing Law............................................................................... 86
    SECTION 11.08.  No Adverse Interpretation of Other Agreements............................................... 86
    SECTION 11.09.  No Recourse Against Others.................................................................. 86
    SECTION 11.10.  Successors.................................................................................. 86
    SECTION 11.11.  Duplicate Originals......................................................................... 86
    SECTION 11.12.  Separability................................................................................ 86
    SECTION 11.13.  Table of Contents, Headings, Etc............................................................ 87
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                                                v
<TABLE>
<S>                                                                                                            <C>
EXHIBIT A         Form of Note................................................................................. A-1
EXHIBIT B         Form of Certificate.......................................................................... B-1
EXHIBIT C         Form of Certificate to be Delivered in Connection with
                     Transfers Pursuant to Regulation S........................................................ C-1
EXHIBIT D         Form of Certificate to be Delivered in Connection with
                     Transfers to Non-QIB Accredited Investors................................................. D-1
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