<PAGE>   1
                                                                     EXHIBIT 4.1

                                                                  EXECUTION COPY


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                          IMPSAT FIBER NETWORKS, INC.,
                                    as Issuer




                                       and




                              THE BANK OF NEW YORK,
                     as Trustee, Registrar and Paying Agent
                                       and
                    BANQUE INTERNATIONALE A LUXEMBOURG S.A.,
                       as Paying Agent and Transfer Agent


                             Senior Notes Indenture

                          Dated as of February 16, 2000





                          13 3/4% Senior Notes due 2005




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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; 10.02
Section 314(a)..................................................................        4.19; 10.02
        (a)(4)..................................................................        4.18; 10.02
        (c)(1)..................................................................        10.03
        (c)(2)..................................................................        10.03
        (e).....................................................................        10.04
Section 315(b)..................................................................        7.05; 10.02
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)..................................................................        10.01
        (c).....................................................................        10.01
</TABLE>




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


<PAGE>   3




                                TABLE OF CONTENTS


<TABLE>
<CAPTION>
                                                                                                                      Page
<S>     <C>                                                                                                           <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...............................................20

        SECTION 1.03.  Rules of Construction...........................................................................20


ARTICLE TWO      THE SECURITIES

        SECTION 2.01.  Form and Dating.................................................................................21

        SECTION 2.02.  Restrictive Legends.............................................................................22

        SECTION 2.03.  Execution, Authentication and Denominations.....................................................24

        SECTION 2.04.  Registrar and Paying Agent......................................................................25

        SECTION 2.05.  Paying Agent to Hold Money in Trust.............................................................26

        SECTION 2.06.  Transfer and Exchange...........................................................................27

        SECTION 2.07.  Book-Entry Provisions for Global Securities.....................................................27

        SECTION 2.08.  Special Transfer Provisions.....................................................................29

        SECTION 2.09.  Replacement Securities..........................................................................32

        SECTION 2.10.  Outstanding Securities..........................................................................32

        SECTION 2.11.  Temporary Securities............................................................................33

        SECTION 2.12.  Cancellation....................................................................................33

        SECTION 2.13.  CUSIP, CINS and ISIN Numbers....................................................................33
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        of the Indenture.


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<TABLE>
<S>     <C>                                                                                                           <C>

        SECTION 2.14.  Defaulted Interest..............................................................................33

        SECTION 2.15.  Issuance of Additional Securities...............................................................34


ARTICLE THREE    REDEMPTION

        SECTION 3.01.  Right of Redemption.............................................................................34

        SECTION 3.02.  Notices to Trustee..............................................................................35

        SECTION 3.03.  Selection of Securities to Be Redeemed..........................................................36

        SECTION 3.04.  Notice of Redemption............................................................................36

        SECTION 3.05.  Effect of Notice of Redemption..................................................................37

        SECTION 3.06.  Deposit of Redemption Price.....................................................................37

        SECTION 3.07.  Payment of Securities Called for Redemption.....................................................37

        SECTION 3.08.  Securities Redeemed in Part.....................................................................38


ARTICLE FOUR     COVENANTS

        SECTION 4.01.  Payment of Securities...........................................................................38

        SECTION 4.02.  Maintenance of Offices or Agencies..............................................................38

        SECTION 4.03.  Limitation on Indebtedness......................................................................39

        SECTION 4.04.  Limitation on Restricted Payments...............................................................41

        SECTION 4.05.  Limitation on Dividend and Other Payment Restrictions
               Affecting Restricted Subsidiaries.......................................................................44

        SECTION 4.06.  Limitation on the Issuance and Sale of Capital Stock of
               Restricted Subsidiaries.................................................................................45

        SECTION 4.07.  Limitation on Issuances of Guarantees
               by Restricted Subsidiaries..............................................................................45

        SECTION 4.08.  Limitation on Transactions with Shareholders and Affiliates.....................................46
</TABLE>


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        of the Indenture.


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<TABLE>
<S>     <C>                                                                                                           <C>
        SECTION 4.09.  Limitation on Liens.............................................................................46

        SECTION 4.10.  Limitation on Sale-Leaseback Transactions.......................................................47

        SECTION 4.11.  Limitation on Asset Sales.......................................................................47

        SECTION 4.12.  Repurchase of Securities upon a Change of Control...............................................48

        SECTION 4.13.  Existence.......................................................................................49

        SECTION 4.14.  Payment of Taxes and Other Claims...............................................................49

        SECTION 4.15.  Maintenance of Properties and Insurance.........................................................49

        SECTION 4.16.  Notice of Defaults..............................................................................50

        SECTION 4.17.  Compliance Certificates.........................................................................50

        SECTION 4.18.  Commission Reports and Reports to Holders.......................................................50

        SECTION 4.19.  Waiver of Stay, Extension or Usury Laws.........................................................51


ARTICLE FIVE     SUCCESSOR CORPORATION

        SECTION 5.01.  When Company May Merge, Etc.....................................................................51

        SECTION 5.02.  Successor Substituted...........................................................................52


ARTICLE SIX      DEFAULT AND REMEDIES

        SECTION 6.01.  Events of Default...............................................................................52

        SECTION 6.02.  Acceleration....................................................................................54

        SECTION 6.03.  Other Remedies..................................................................................54

        SECTION 6.04.  Waiver of Past Defaults.........................................................................55

        SECTION 6.05.  Control by Majority.............................................................................55

        SECTION 6.06.  Limitation on Suits.............................................................................55
</TABLE>


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        of the Indenture.


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<TABLE>
<S>     <C>                                                                                                           <C>
        SECTION 6.07.  Rights of Holders to Receive Payment............................................................56

        SECTION 6.08.  Collection Suit by Trustee......................................................................56

        SECTION 6.09.  Trustee May File Proofs of Claim................................................................56

        SECTION 6.10.  Priorities......................................................................................56

        SECTION 6.11.  Undertaking for Costs...........................................................................57

        SECTION 6.12.  Restoration of Rights and Remedies..............................................................57

        SECTION 6.13.  Rights and Remedies Cumulative..................................................................57

        SECTION 6.14.  Delay or Omission Not Waiver....................................................................57


ARTICLE SEVEN    TRUSTEE AND AGENTS

        SECTION 7.01.  General.........................................................................................58

        SECTION 7.02.  Certain Rights..................................................................................58

        SECTION 7.03.  Individual Rights of Trustee....................................................................59

        SECTION 7.04.  Trustee's Disclaimer............................................................................59

        SECTION 7.05.  Notice of Default...............................................................................59

        SECTION 7.06.  Reports by Trustee to Holders...................................................................60

        SECTION 7.07.  Compensation and Indemnity......................................................................60

        SECTION 7.08.  Replacement of Trustee..........................................................................60

        SECTION 7.09.  Successor Trustee by Merger, Etc................................................................61

        SECTION 7.10.  Eligibility.....................................................................................62

        SECTION 7.11.  Money Held in Trust.............................................................................62

        SECTION 7.12.  Withholding Taxes...............................................................................62
</TABLE>


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        of the Indenture.


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<TABLE>
<S>     <C>                                                                                                           <C>
ARTICLE EIGHT    DISCHARGE OF INDENTURE

        SECTION 8.01.  Termination of Company's Obligations............................................................62

        SECTION 8.02.  Defeasance and Discharge of Indenture...........................................................63

        SECTION 8.03.  Defeasance of Certain Obligations...............................................................65

        SECTION 8.04.  Application of Trust Money......................................................................67

        SECTION 8.05.  Repayment to Company............................................................................67

        SECTION 8.06.  Reinstatement...................................................................................67

        SECTION 8.07.  Insiders........................................................................................68


ARTICLE NINE     AMENDMENTS, SUPPLEMENTS AND WAIVERS

        SECTION 9.01.  Without Consent of Holders......................................................................68

        SECTION 9.02.  With Consent of Holders.........................................................................68

        SECTION 9.03.  Revocation and Effect of Consent................................................................69

        SECTION 9.04.  Notation on or Exchange of Securities...........................................................70

        SECTION 9.05.  Trustee to Sign Amendments, Etc.................................................................70

        SECTION 9.06.  Conformity with Trust Indenture Act.............................................................70


ARTICLE TEN      MISCELLANEOUS

        SECTION 10.01.  Trust Indenture Act of 1939....................................................................71

        SECTION 10.02.  Notices........................................................................................71

        SECTION 10.03.  Certificate and Opinion as to Conditions Precedent.............................................72

        SECTION 10.04.  Statements Required in Certificate or Opinion..................................................72

        SECTION 10.05.  Rules by Trustee, Paying Agent or Registrar....................................................73
</TABLE>



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        of the Indenture.


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<TABLE>
<S>     <C>                                                                                                           <C>
        SECTION 10.06.  Payment Date Other Than a Business Day.........................................................73

        SECTION 10.07.  Governing Law..................................................................................73

        SECTION 10.08.  No Adverse Interpretation of Other Agreements..................................................73

        SECTION 10.09.  No Recourse Against Others.....................................................................73

        SECTION 10.10.  Successors.....................................................................................74

        SECTION 10.11.  Duplicate Originals............................................................................74

        SECTION 10.12.  Currency Indemnity.  ..........................................................................74

        SECTION 10.13.  Currency Translations..........................................................................74

        SECTION 10.14.  Table of Contents, Headings, Etc...............................................................74
</TABLE>



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        of the Indenture.


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<TABLE>
<S>                                                                                                                     <C>
EXHIBIT A        Form of Security.........................................................................................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
</TABLE>



<PAGE>   10


              INDENTURE, dated as of February 16, 2000, among IMPSAT FIBER
NETWORKS, INC., a Delaware corporation, as issuer (the "Company"), THE BANK OF
NEW YORK, as trustee, registrar and paying agent (the "Trustee") and BANQUE
INTERNATIONALE A LUXEMBOURG S.A., as paying agent and transfer agent.

                             RECITALS OF THE COMPANY

              The Company has duly authorized the execution and delivery of this
Indenture to provide for the issuance initially of up to $300,000,000 aggregate
principal amount of the Company's 13 3/4% Senior Notes due 2005 (the
"Securities") issuable as provided herein. 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 Securities,
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
Securities 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.

              "Acquired Indebtedness" means Indebtedness of a Person existing at
the time such Person becomes a Restricted Subsidiary or assumed in connection
with an Asset Acquisition by a Restricted Subsidiary and not Incurred in
connection with, or in anticipation of, such Person becoming a Restricted
Subsidiary or such Asset Acquisition.

              "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


<PAGE>   11
                                       2


4.04 (and in such case, except to the extent includable 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 4.04, any amount paid or accrued 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; (vi) all extraordinary gains
and extraordinary losses; and (vii) any compensation expense paid or payable
solely with Capital Stock (other than Disqualified Stock) of the Company or any
options, warrants or other rights to acquire Capital Stock (other than
Disqualified Stock) of the Company.

              "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 (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 recent 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; provided that such
Person's primary business is related, ancillary or


<PAGE>   12
                                       3




complementary to the businesses of the Company and its Restricted Subsidiaries
on the date of such investment 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; provided that the property
and assets acquired are related, ancillary or complementary to the businesses of
the Company and its Restricted Subsidiaries on the date of such acquisition.

              "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 transaction) 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 of, or
other Investment in, an Unrestricted 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 equipment that has become obsolete or no longer
useful in the business of the Company or its Restricted Subsidiaries or
inventory, receivables and other current assets, (b) sales, transfers or other
dispositions of assets constituting a Restricted Payment permitted to be made
under Section 4.04, (c) sales, transfers or other dispositions of assets with a
fair market value (as certified in an Officers' Certificate) not in excess of $1
million in any transaction or series of related transactions, (d) 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 kind described in clause (B) of
Section 4.11 or (e) issuances and sales of Common Stock of Restricted
Subsidiaries in accordance with clauses (i), (iii) or (v) of the second
paragraph of Section 4.06.

              "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" means Banco Rio de la Plata S.A. and any other party that
the Board of Directors has determined does not present any material credit risk.


<PAGE>   13
                                       4




              "Board of Directors" means, with respect to any Person, the Board
of Directors of such Person or any committee of such Board of Directors duly
authorized to act with respect to this Indenture.

              "Board Resolution" means, with respect to any Person, a copy of a
resolution, certified by the Secretary or Assistant Secretary of such Person to
have been duly adopted by the Board of Directors of such Person 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.

              "Certificates of Deposit" has the meaning provided in the
definition of Intermediary Documents.

              "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 Voting Stock representing more than 30% of the total voting power of the
Voting Stock of the Company on a fully diluted basis and such ownership
represents a greater percentage 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 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 Securities are
originally issued under this Indenture.


<PAGE>   14
                                       5




              "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 Chief Financial Officer, 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 (other than income taxes (either positive or
negative) attributable to extraordinary and non-recurring gains or losses or
sales of assets) and the portion of any other tax payable as a result of
generating income before taxes, (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 interest paid or


<PAGE>   15
                                       6



accrued (by any Person) on 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 Securities,
the offering of the 12_% Senior Guaranteed Notes due 2003, and the offering of
the 12_% Senior Notes due 2008 all as determined on a consolidated basis
(without taking into account Unrestricted Subsidiaries) in conformity with GAAP.

              "Consolidated Net Worth" means, at any date of determination,
stockholders' equity as set forth on the quarterly or annual consolidated
balance sheet of the Company and its Restricted Subsidiaries most recently filed
with the Commission or provided to the Trustee pursuant to Section 4.18, less
the amount of stockholders' equity attributable to Unrestricted Subsidiaries and
any amounts attributable to Disqualified 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 hereof, located at 101
Barclay Street, Floor 21 West, New York, New York 10286.

              "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" means The Depository Trust Company, its nominees, and
their respective successors.

              "Disqualified 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 Securities, (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 Securities 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 Securities; provided that any
Capital Stock that would not


<PAGE>   16
                                       7



constitute Disqualified 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 Securities shall not constitute Disqualified 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
in favor of Holders that are contained in Section 4.11 and Section 4.12 and such
Capital Stock, or the agreements or instruments governing the redemption rights
thereof, 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 Securities as are required to be repurchased pursuant to Section 4.11 and
Section 4.12.

              "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.

              "Exchange Securities" means any securities of the Company
containing terms identical to the Securities (except that such Exchange
Securities (i) shall be registered under the Securities Act, (ii) will not
provide for an increase in the rate of interest (other than with respect to
overdue amounts) and (iii) will not contain terms with respect to transfer
restrictions) that are issued and exchanged for the Securities pursuant to the
Registration Rights Agreement and this Indenture.

              "Existing Stockholders" means (i) Mr. Enrique Pescarmona, Mrs.
Silvia Monica Pescarmona de Baldini, Mrs. Liliana Pescarmona de Mayol, Mr.
Roberto Vivo and Mr. Ricardo Verdaguer, (ii) a parent, brother or sister of any
of the individuals named in clause (i), (iii) the spouse of any individual named
in clause (i) or (ii), (iv) the lineal descendants of any person named in
clauses (i) through (iii), (v) the estate or any guardian, custodian or other
legal representative of any individual named in clauses (i) through (iv), (vi)
any trust established solely for the benefit of any one or more of the
individuals named in clauses (i) through (v), (vii) any Person in which all of
the equity interests are owned, directly or indirectly, by any one or more of
the Persons named in clauses (i) through (vi) or clauses (viii), (ix) or (xii),
(viii) Nevasa Holdings Ltd., (ix) Corporacion IMPSA, S.A., (x) Princes Gate
Investors II, L.P., (xi) Morgan Stanley Global Emerging Markets Private
Investment Fund, L.P., (xii) British Telecommunications plc and (xiii) any
Affiliate of either of the Persons named in clauses (x), (xi) or (xii).

              "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 Board of Directors, whose determination shall
be conclusive if evidenced by a Board Resolution.

              "GAAP" means generally accepted accounting principles in the
United States of America as in effect as of the date of determination,
including, without limitation, those set forth


<PAGE>   17
                                       8



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 contained or referred to
herein 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 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 Securities, the offering of the 12_% Senior
Guaranteed Notes due 2003 and the offering of the 12_% Senior Notes due 2008,
(ii) except as otherwise provided, the amortization of any amounts required or
permitted by Accounting Principles Board Opinion Nos. 16 and 17 and (iii) any
nonrecurring charges associated with the adoption, after the Closing Date, of
Financial Accounting Standard Nos. 106 and 109.

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

              "Guarantee" means any obligation, contingent or otherwise, of any
Person directly or indirectly guaranteeing any Indebtedness or other obligation
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 or other obligation 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 or other obligation 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
4.07.

              "Holder" or "Securityholder" means the then registered holder of
any Security.

              "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, with respect to the Company and its Restricted
Subsidiaries, 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


<PAGE>   18
                                       9



reimbursement obligations with respect thereto, but excluding obligations with
respect to letters of credit (including trade letters of credit) securing
obligations (other than obligations described in (i) or (ii) above or (v), (vi)
or (vii) below) entered into in the ordinary course of business of such Person
to the extent such letters of credit are not drawn upon or, if drawn upon, to
the extent such drawing is reimbursed no later than the third Business Day
following such drawing), (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 (without duplication) 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 (unless the underlying contingency has
not occurred and the occurrence of the underlying contingency is entirely within
the control of the Company or its Restricted Subsidiaries), provided (A) that
the amount outstanding at any time of any Indebtedness issued with original
issue discount is the original issue price of such Indebtedness, (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" and (C) that Indebtedness shall not include any
liability for federal, state, local or other taxes.

              "Indebtedness to EBITDA 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 Quarter Period through
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



<PAGE>   19
                                       10



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.

              "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) of Regulation D under the Securities Act.

              "Intelsat" has the meaning provided in the definition of Permitted
Investment.

              "Interest Payment Date" means each semiannual interest payment
date on February 15 and August 15 of each year, commencing August 15, 2000.

              "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.

              "Intermediary Documents" means documents relating to the issuance
of one or more Certificates of Deposit (the "Certificates of Deposit") by the
Issuer to the Company, the issuance of one or more promissory notes (having a
principal amount equal to the principal amount of the Certificate of Deposit
(the "Promissory Notes")) by any Restricted Subsidiary to the Bank and the
Guarantees of the Promissory Notes by the Company.

              "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 (other
than Unrestricted Subsidiaries of the Company) and accounts payable to suppliers
in the ordinary course of business that are, in conformity with GAAP, recorded
as accounts receivable or accounts payable, as the case may be, on the balance
sheet of the Company or its Restricted Subsidiaries and Trade Payables) 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 4.06. For
purposes of the definition of "Unrestricted Subsidiary" and Section 4.04, (i)
"Investment" shall include the fair market value of the assets (net of
liabilities, other than liabilities to the Company



<PAGE>   20
                                       11



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.

              "Issuer" means the Cayman Islands branch of the Bank or any other
party that the Board of Directors has determined does not present any material
credit risk.

              "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, any sale with
recourse against the seller or any Affiliate of the seller, or any agreement to
give any security interest), but excluding any right of first refusal.

              "Moody's" means Moody's Investor 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, 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
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 agent 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.



<PAGE>   21
                                       12



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

              "Offer to Purchase" means an offer to purchase Securities 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 such Securities 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 such
notice is mailed) (the "Payment Date"); (iii) that any such Security not
tendered will continue to accrue interest pursuant to its terms; (iv) that,
unless the Company defaults in the payment of the purchase price, any Security
accepted for payment pursuant to the Offer to Purchase shall cease to accrue
interest on and after the Payment Date; (v) that Holders electing to have such
Security purchased pursuant to the Offer to Purchase will be required to
surrender the Security, together with the form entitled "Option of the Holder to
Elect Purchase" on the reverse side of the Security 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 of Securities delivered for purchase
and a statement that such Holder is withdrawing his election to have such
Securities purchased; and (vii) that Holders whose Securities are being
purchased only in part will be issued new Securities equal in principal amount
to the unpurchased portion of the Securities surrendered; provided that each
Security purchased and each new Security issued shall be in a principal amount
of $1,000 or an integral multiple thereof. On the Payment Date, the Company
shall (i) accept for payment on a pro rata basis Securities 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 Securities or portions thereof
so accepted; and (iii) deliver, or cause to be delivered, to the Trustee all
Securities or portions thereof so accepted together with an Officers'
Certificate specifying the Securities or portions thereof accepted for payment
by the Company. The Paying Agent shall promptly mail to the Holders of
Securities so accepted payment in an amount equal to the purchase price, and the
Trustee shall promptly authenticate and mail to such Holders a new Security
equal in principal amount to any unpurchased portion of the Security
surrendered; provided that each Security purchased and each new Security issued
shall be in a principal amount of $1,000 or an integral multiple 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 Securities pursuant to an Offer to Purchase.

              "Officer" means with respect to any Person, (i) the Chairman of
the Board, the Vice 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.



<PAGE>   22
                                       13




              "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; provided, however, that any such certificate may
be signed by any two of the Officers listed in clause (i) of the definition
thereof in lieu of being 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).

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

              "Offshore Physical Securities" 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 Date" has the meaning provided in the definition of
"Offer to Purchase."

              "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) loans or advances to employees made in the
ordinary course of business in accordance with past practice of the Company or
its Restricted Subsidiaries and that do not in the aggregate exceed $1 million
at any time outstanding; (v) stock, obligations or securities received in
satisfaction of judgments, work-outs or similar arrangements; (vi) Investments,
in an aggregate amount at any one time outstanding not to exceed $30 million in
Common Stock of the International Telecommunications Satellite Organization
("Intelsat"); (vii) participations in Indebtedness of any Restricted Subsidiary
permitted to be Incurred by clause (xii) of the second paragraph of Section
4.03; and (viii) Investments consisting of one or more Certificates of Deposit,
having an aggregate principal amount not to exceed the aggregate principal
amount of the Promissory Notes then outstanding; provided that (1) upon making
any such Investment after the Closing Date, the Company shall deliver an
Officers' Certificate to the Trustee, to the effect that applicable law
regarding rights of set off has not changed since the Closing Date, (2) the
Stated Maturity of each such Certificate of Deposit shall be the same as a
Promissory Note of equal



<PAGE>   23
                                       14



principal amount and (3) at the time that any Investment in any Certificate of
Deposit is made the Company shall deliver an Officer's Certificate to the
Trustee to the effect that (A) the Bank and the Issuer are not under
intervention, receivership or any similar arrangement or proceeding and (B) the
Company does not have any reason to believe there is a material possibility that
the Bank or the Issuer may be subject to intervention, receivership or any
similar arrangement or proceeding.

              "Permitted Liens" means (i) Liens for taxes, assessments,
governmental charges or claims that are being contested in good faith by
appropriate legal proceedings promptly instituted and diligently conducted and
for which a reserve or other appropriate provision, if any, as shall be required
in conformity with GAAP shall have been made; (ii) statutory and common law
Liens of landlords and carriers, warehousemen, mechanics, suppliers,
materialmen, repairmen or other similar Liens arising in the ordinary course of
business and with respect to amounts not yet delinquent or being contested in
good faith by appropriate legal proceedings promptly instituted and diligently
conducted and for which a reserve or other appropriate provision, if any, as
shall be required in conformity with GAAP shall have been made; (iii) Liens
incurred or deposits made in the ordinary course of business in connection with
workers' compensation, unemployment insurance and other types of social
security; (iv) Liens incurred or deposits made to secure the performance of
tenders, bids, leases, statutory or regulatory obligations, bankers'
acceptances, surety and appeal bonds, contracts (other than for Indebtedness),
performance and return-of-money bonds and other obligations of a similar nature
incurred in the ordinary course of business (exclusive of obligations for the
payment of borrowed money) and any bank's unexercised right of setoff with
respect to deposits made in the ordinary course of business of the Company or
any Restricted Subsidiary; (v) easements, rights-of-way, municipal and zoning
ordinances and similar charges, encumbrances, title defects or other
irregularities that do not materially interfere with the ordinary course of
business of the Company or any of its Restricted Subsidiaries; (vi) Liens
(including extensions and renewals thereof) upon real or personal property
acquired after the Closing Date; provided that (a) such Lien is created solely
for the purpose of securing Indebtedness Incurred, in accordance with Section
4.03, (1) to finance the cost (including the cost of design, development,
acquisition, construction, installation, improvement, transportation or
integration) of the item of property or assets subject thereto and such Lien is
created prior to, at the time of or within six months after the later of the
acquisition, the completion of construction or the commencement of full
operation of such property or (2) to refinance any Indebtedness previously so
secured, (b) the principal amount of the Indebtedness secured by such Lien does
not exceed 100% of such cost and (c) any such Lien shall not extend to or cover
any property or assets other than such item of property or assets and any
improvements on such item; (vii) leases or subleases granted to others that do
not materially interfere with the ordinary course of business of the Company and
its Restricted Subsidiaries, taken as a whole; (viii) Liens encumbering property
or assets under construction arising from progress or partial payments by a
customer of the Company or its Restricted Subsidiaries relating to such property
or assets; (ix) any interest or title of a lessor in the property subject to any
Capitalized Lease or operating lease; (x) Liens arising from filing Uniform
Commercial Code financing statements regarding leases; (xi) Liens on property
of, or on shares of Capital Stock or Indebtedness of, any Person existing at the
time such Person becomes, or becomes a part of, any Restricted Subsidiary;
provided that such Liens do not extend to or cover any property or assets



<PAGE>   24
                                       15



of the Company or any Restricted Subsidiary other than the property or assets
acquired; (xii) Liens in favor of the Company or any Restricted Subsidiary;
(xiii) Liens arising from the rendering of a final judgment or order against the
Company or any Restricted Subsidiary that does not give rise to an Event of
Default; (xiv) Liens securing reimbursement obligations with respect to letters
of credit that encumber documents and other property relating to such letters of
credit and the products and proceeds thereof; (xv) Liens in favor of customs and
revenue authorities arising as a matter of law to secure payment of customs
duties in connection with the importation of goods; (xvi) Liens encumbering
customary initial deposits and margin deposits, and other Liens that are within
the general parameters customary in the industry and incurred in the ordinary
course of business, in each case, securing Indebtedness under Interest Rate
Agreements, Currency Agreements and forward contracts, options, future
contracts, futures options or similar agreements or arrangements designed solely
to protect the Company or any of its Restricted Subsidiaries from fluctuations
in interest rates, currencies or the price of commodities; (xvii) Liens arising
out of conditional sale, title retention, consignment or similar arrangements
for the sale of goods entered into by the Company or any of its Restricted
Subsidiaries in the ordinary course of business in accordance with the past
practices of the Company and its Restricted Subsidiaries prior to the Closing
Date; (xviii) Liens on or sales of receivables; and (xix) Liens that secure
Indebtedness with an aggregate principal amount not in excess of $5 million at
any time outstanding.

              "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 Securities" 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 this Indenture, including,
without limitation, all series and classes of such preferred or preference
stock.

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

              "Private Placement Legend" means the legend initially set forth on
the Securities in the form set forth in Section 2.02(a).

              "Promissory Notes" has the meaning provided for in the definition
of Intermediary Documents.

              "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.



<PAGE>   25
                                       16




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

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

              "Redemption Price" means, when used with respect to any Security
to be redeemed, the price at which such Security 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 February 16, 2000, between the Company and Morgan Stanley
& Co. Incorporated.

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

              "Regular Record Date" for the interest payable on any Interest
Payment Date means the February 1 or August 1(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 any vice president, any assistant vice president, any assistant secretary,
any assistant treasurer, and any trust officer or assistant trust officer
employed in the conduct of the Trustee's corporate trust business, 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 4.04.

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

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

              "Securities" means any of the securities, 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 "Securities" shall
include any Exchange Securities to be issued and exchanged for any Securities
pursuant to the Registration Rights Agreement and this Indenture and, for
purposes of this Indenture, all Securities and Exchange Securities shall vote
together as one series of Securities under this Indenture.

              "Securities Act" means the Securities Act of 1933.



<PAGE>   26
                                       17




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

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

              "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 consolidated financial statements of the Company for the fiscal
year most recently filed pursuant to Section 4.18.

              "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.

              "Strategic Subordinated Indebtedness" means Indebtedness of the
Company Incurred to finance the acquisition of a Person engaged in a business
that is related, ancillary or complementary to the business conducted by the
Company or any of its Restricted Subsidiaries, which Indebtedness by its terms,
or by the terms of any agreement or instrument pursuant to which such
Indebtedness is Incurred, (i) is expressly made subordinate in right of payment
to the Securities and (ii) provides that no payment in cash or assets of the
Company or any Restricted Subsidiaries of principal, premium or interest on, or
any other payment with respect to, such Indebtedness may be made prior to the
payment in full of all of the Company's obligations under the Securities;
provided that such Indebtedness may provide for and be repaid at any time from
the proceeds of a capital contribution or the sale of Capital Stock (other than
Disqualified Stock) of the Company after the Incurrence of such Indebtedness.

              "Subsidiary" means, with respect to any Person, any corporation,
association or other business entity of which Voting Stock representing more
than 50% of the total voting power of the outstanding 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 4.07.

              "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 one year of the date of



<PAGE>   27
                                       18



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
one year 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, (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, (vi) certificates of deposit maturing not more than one year
after the acquisition thereof by a Restricted Subsidiary and issued by any of
the ten largest banks (based on assets as of the last December 31) organized
under the laws of the country in which the Restricted Subsidiary that acquires
such certificates of deposit is organized, provided that such bank is not under
intervention, receivership or any similar arrangement at the time of the
acquisition of such certificates of deposit and (vii) direct obligations of the
government of Japan made to facilitate a reduction in withholding taxes;
provided that the Company takes adequate steps in the opinion of its chief
financial officer to hedge any currency risk associated therewith.

              "TIA" or "Trust Indenture Act" means the Trust Indenture Act of
1939, as amended (15 U.S. Code Sections 77aaa-77bbbb), 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 and required to be paid within one year.

              "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.

              "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.

              "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



<PAGE>   28
                                       19



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 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 4.04; and (C) if applicable, the Incurrence of
Indebtedness would be permitted under this Indenture. The Board of Directors may
designate any Unrestricted Subsidiary to be a Restricted Subsidiary; provided
that immediately after giving effect to such designation (x) the Company could
Incur $1.00 of additional Indebtedness under the first paragraph of Section 4.03
and (y) no Default or Event of Default shall have occurred and be continuing.
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.

              "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.

              "U.S. Global Security" 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 Securities, and shall also include a depository
receipt issued by a bank or trust company as custodian with respect to any such
U.S. Government 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. Person" has the meaning ascribed thereto in Rule 902 under
the Securities Act.

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



<PAGE>   29
                                       20




              "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.

              "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 herein have the following meanings:

              "indenture securities" means the Securities;

              "indenture security holder" means a Holder or a Securityholder;

              "indenture to be qualified" means this Indenture;

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

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

              All other TIA terms used herein 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; and



<PAGE>   30
                                       21



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


                                   ARTICLE TWO
                                 THE SECURITIES

              SECTION 2.01. Form and Dating. The Securities and the Trustee's
certificate of authentication shall be substantially in the form annexed hereto
as Exhibit A. The Securities 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 Securities and any notation,
legend or endorsement on the Securities. Each Security shall be dated the date
of its authentication.

              The terms and provisions contained in the form of the Securities
annexed hereto as Exhibit A shall constitute, and are hereby expressly made, a
part of this Indenture. Each of the Company and the Trustee, by its execution
and delivery of this Indenture, expressly agrees to the terms and provisions of
the Securities applicable to it and to be bound thereby.

              Securities offered and sold in reliance on Rule 144A shall be
issued in the form of one or more permanent global Securities in registered
form, substantially in the form set forth in Exhibit A (collectively, the "U.S.
Global Security"), 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 Security 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.

              Securities offered and sold in offshore transactions in reliance
on Regulation S shall be issued in the form of one or more global Securities in
registered form substantially in the form set forth in Exhibit A (collectively,
the "Offshore Global Security") 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
Security 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.

              Securities offered and sold to Institutional Accredited Investors
which are not QIBs (excluding Non-U.S. Persons) shall be issued in the form of
permanent certificated Securities in registered form in substantially the form
set forth in Exhibit A (the "U.S. Physical Securities"). Securities issued
pursuant to Section 2.07 in exchange for interests in the Offshore Global
Security shall be in the form of permanent certificated Securities in registered
form substantially in the form set forth in Exhibit A (the "Offshore Physical
Securities").

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



<PAGE>   31
                                       22



              The definitive Securities 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
Securities may be listed, all as determined by the Officers executing such
Securities, as evidenced by their execution of such Securities.

              SECTION 2.02. Restrictive Legends. (a) Unless and until a Security
is exchanged for an Exchange Security or sold in connection with an effective
Registration Statement pursuant to the Registration Rights Agreement, (i) the
U.S. Global Security and each U.S. Physical Security shall bear the legend set
forth below on the face thereof and (ii) the Offshore Physical Securities and
the Offshore Global Security shall bear the legend set forth below on the face
thereof until at least 41 days 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 UNDER RULE 144(k) UNDER THE SECURITIES
       ACT AS IN EFFECT ON THE DATE OF THE TRANSFER OF THIS NOTE, RESELL OR
       OTHERWISE TRANSFER THIS NOTE EXCEPT (A) TO THE COMPANY OR ANY SUBSIDIARY
       THEREOF, (B) 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 AGGREGATE PRINCIPAL AMOUNT 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



<PAGE>   32
                                       23



       TRANSACTION IN COMPLIANCE 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 (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 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.

                     (b)    Each Global Security, whether or not an Exchange
       Security, shall also bear the following legend on the face thereof:

              UNLESS THIS NOTE 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 NOTE ISSUED
              IS REGISTERED IN THE NAME OF CEDE & CO. OR IN 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.



<PAGE>   33
                                       24



              TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN
              WHOLE, BUT NOT IN PART, TO THE DEPOSITORY TRUST COMPANY OR
              NOMINEES OF THE DEPOSITORY TRUST COMPANY OR TO A SUCCESSOR THEREOF
              OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS OF PORTIONS OF THIS
              GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS 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 and applicable law, the aggregate principal amount of Securities
which may be authenticated and delivered under this Indenture is unlimited. The
Securities shall be executed by two Officers of the Company. The signature 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 Security no longer holds
that office at the time the Trustee or authenticating agent authenticates the
Security, the Security shall be valid nevertheless.

              A Security shall not be valid until an authorized signatory of the
Trustee or authenticating agent manually signs the certificate of authentication
on the Security. The signature shall be conclusive evidence that the Security
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 Securities in the aggregate
principal amount specified in such Company Order; provided that the Trustee
shall receive an Officers' Certificate and an Opinion of Counsel of the Company
in connection with such authentication of Securities. The Opinion of Counsel
shall be to the effect that:

              (a)    the form and terms of such Securities have been established
       by or pursuant to a Board Resolution or, if applicable, an indenture
       supplemental hereto in conformity with the provisions of this Indenture;

              (b)    such supplemental indenture, if any, when executed and
       delivered by the Company and the Trustee, will constitute a valid and
       binding obligation of the Company;

              (c)    such Securities, when authenticated and delivered by the
       Trustee and issued by the Company in the manner and subject to any
       conditions specified in such Opinion of Counsel, will constitute valid
       and binding obligations of the Company in accordance with their terms and
       will be entitled to the benefits of this Indenture, subject to
       bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium
       and similar



<PAGE>   34
                                       25



       laws of general applicability relating to or affecting creditors' rights
       and to general equitable principles; and

              (d)    the Company has been duly incorporated in, and is a validly
       existing corporation in good standing under the laws of, the State of
       Delaware.

Such Company Order shall specify the amount of Securities to be authenticated
and the date on which the original issue of Securities is to be authenticated
and, in the case of an issuance of Securities 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
Securities. An authenticating agent may authenticate Securities 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 Securities shall be issuable only in registered form without
coupons and only in denominations of $1,000 in principal amount and any integral
multiple of $1,000 in excess thereof.

              SECTION 2.04. Registrar and Paying Agent. The Company shall
maintain an office or agency where Securities may be presented for registration
of transfer or for exchange (the "Registrar"), an office or agency where
Securities 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
Securities and this Indenture may be served, which shall be in the Borough of
Manhattan, The City of New York. In addition, so long as the Securities are
listed on the Luxembourg Stock Exchange and the Luxembourg Stock Exchange so
requires, there will be a Paying Agent and transfer agent in Luxembourg where
Securities may be presented for registration of transfer or for exchange and
where Securities may be presented for payment. The Company initially appoints
Banque Internationale a Luxembourg as such Paying Agent and transfer agent in
Luxembourg. The Company shall cause the Registrar to keep a register of the
Securities and of their transfer and exchange (the "Security Register"). 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 for so long as such failure shall continue and shall be
entitled to compensation therefor pursuant to Section 7.07. 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



<PAGE>   35
                                       26



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; provided, however, that neither
the Company, a Subsidiary of the Company nor an Affiliate of any of them shall
act as Paying Agent in connection with the defeasance of the Securities or the
discharge of this Indenture under Article Eight.

              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 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 Security Register.

              SECTION 2.05. Paying Agent to Hold Money in Trust. Not later than
11:00 a.m. New York City time on each due date of the principal, premium, if
any, and interest on any Securities, the Company shall deposit with the Trustee
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, if any, 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 Securities (whether such money has been paid to it by the
Company or any other obligor on the Securities), and that such Paying Agent
shall promptly notify the Trustee in writing of any default by the Company (or
any other obligor on the Securities) 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 Securities, 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 in writing of its action or failure to act as
required by this Section 2.05. The Trustee shall arrange with all Paying Agents
for the payment, from funds furnished by the Company to the Trustee pursuant to
this Indenture, of principal and interest on the Securities and of the
compensation of the Paying Agents for their services as such from funds
furnished by the Company to the Trustee.

              SECTION 2.06. Transfer and Exchange. The Securities are issuable
only in registered form. A Holder may transfer a Security 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


<PAGE>   36
                                       27



Holder only upon, registration of the transfer by the Registrar in the Security
Register. Prior to the registration of any transfer by a Holder as provided
herein, the Company, the Trustee, and any agent of the Company or the Trustee
shall treat the person in whose name the Security is registered as the owner
thereof for all purposes whether or not the Security 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 or beneficial owner of an interest
in a Global Security shall, by acceptance of such Global Security, be deemed to
have agreed that transfers of beneficial interests in such Global Security may
be effected only through a book-entry system maintained by the Depositary (or
its agent), and that ownership of a beneficial interest in the Security shall be
required to be reflected in a book entry. When Securities 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 Securities of other authorized
denominations (including on exchange of Securities for Exchange Securities), 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
Securities for Exchange Securities shall occur until a Registration Statement
shall have been declared effective by the Commission and that any Securities
that are exchanged for Exchange Securities shall be canceled by the Trustee. To
permit registrations of transfers and exchanges in accordance with the terms,
conditions and restrictions hereof, the Company shall execute and the Trustee
shall authenticate Securities at the Registrar's request. No service charge
shall be made to any Holder for any registration of transfer or exchange or
redemption of the Securities, but the Company may require payment by the Holder
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 transfers, exchanges or redemptions
pursuant to Section 2.11, 3.08 or 9.04).

              The Registrar shall not be required (i) to issue, register the
transfer of or exchange any Security during a period beginning at the opening of
business 15 days before the day of the mailing of a notice of redemption of
Securities selected for redemption under Section 3.03 or Section 3.08 and ending
at the close of business on the day of such mailing, or (ii) to register the
transfer of or exchange any Security so selected for redemption in whole or in
part, except the unredeemed portion of any Security being redeemed in part.

              SECTION 2.07. Book-Entry Provisions for Global Securities. (a) The
U.S. Global Security and Offshore Global Security initially shall (i) be
registered in the name of the Depositary for such Global Securities 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 Security
held on their behalf by the Depositary, or the Trustee as its custodian, or
under any Global Security, 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 Security 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


<PAGE>   37
                                       28



operation of customary practices governing the exercise of the rights of a
beneficial owner of any Security.

              (b)    Transfers of a Global Security shall be limited to
transfers of such Global Security in whole, but not in part, to the Depositary,
its successors or their respective nominees. Interests of beneficial owners in a
Global Security may be transferred in accordance with the applicable rules and
procedures of the Depositary and the provisions of Section 2.08. In addition,
Physical Securities shall be transferred to all beneficial owners in exchange
for their beneficial interests in the U.S. Global Security or the Offshore
Global Security, respectively, if (i) the Depositary notifies the Company that
it is unwilling or unable to continue as Depositary for the U.S. Global Security
or the Offshore Global Security, 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 Securities
that is transferred to a person who takes delivery in the form of an interest in
the other Global Security will, upon transfer, cease to be an interest in such
Global Security and become an interest in the other Global Security and,
accordingly, will thereafter be subject to all transfer restrictions, if any,
and other procedures applicable to beneficial interests in such other Global
Security for as long as it remains such an interest.

              (d)    In connection with any transfer pursuant to paragraph (b)
of this Section 2.07 of a portion of the beneficial interests in a Global
Security to beneficial owners who are required to hold Physical Securities, the
Registrar shall reflect on its books and records the date and a decrease in the
principal amount of the Global Security in an amount equal to the principal
amount of the beneficial interest in the Global Security to be transferred, and
the Company shall execute, and the Trustee shall authenticate and deliver, one
or more Physical Securities of like tenor and amount.

              (e)    In connection with the transfer of an entire Global
Security to beneficial owners pursuant to paragraph (b) of this Section 2.07,
the Global Security 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 Global Security an equal aggregate principal
amount of Physical Securities of authorized denominations.

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

              (g)    The registered holder of a Global Security 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 Securities.


<PAGE>   38
                                       29



              (h)    QIBs that are beneficial owners of interests in a Global
Security may receive Physical Securities (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 Physical Securities, the Registrar shall reflect on its books and records a
decrease in the principal amount of the relevant Global Security equal to the
principal amount of such Physical Securities and the Company shall execute and
the Trustee shall authenticate and deliver one or more Physical Securities
having an equal aggregate principal amount.

              SECTION 2.08. Special Transfer Provisions. Unless and until a
Security is exchanged for an Exchange Security or sold in connection with an
effective Registration Statement pursuant to the Registration Rights Agreement,
transfers of a Security or of Securities shall only be permitted as specified
below:

              (a)    Transfers to QIBs.  The following provisions shall apply
with respect to the registration of any proposed transfer of a U.S. Physical
Security or an interest in the U.S. Global Security to a QIB (excluding Non-U.S.
Persons):

              (i)    If the Security to be transferred consists of (A) U.S.
       Physical Securities, 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 Security 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 Security stating, or
       has otherwise advised the Company and the Registrar in writing, that it
       is purchasing the Security 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 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 (B) an interest in the U.S. Global
       Security, 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
       Security to be transferred consists of U.S. Physical Securities, 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 Security in an amount equal to the principal amount of the U.S.
       Physical Securities to be transferred, and the Trustee shall cancel the
       U.S. Physical Securities so transferred.


<PAGE>   39
                                       30



              (b)    Transfers of Interests in the Offshore Global Security or
Offshore Physical Securities to U.S. Persons. The following provisions shall
apply with respect to any transfer of interests in the Offshore Global Security
or Offshore Physical Securities to U.S. Persons:

              (i)    prior to the removal of the Private Placement Legend from
       the Offshore Global Security or Offshore Physical Securities pursuant to
       Section 2.02, the Registrar shall refuse to register such transfer unless
       the Registrar receives with respect to such transfer the documents and
       instruments required by Section 2.08(a) or Section 2.08(c), as the case
       may be; and

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

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

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

              (ii)   (A) If the proposed transferor is an Agent Member holding a
       beneficial interest in the U.S. Global Security, upon receipt by the
       Registrar of (1) the documents required by paragraph (i) and (2)
       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 the U.S. Global Security in an
       amount equal to the principal amount of the beneficial interest in the
       U.S. Global Security to be transferred, and (B) if the proposed
       transferee is an Agent Member, upon receipt by 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 Security in an amount equal to the principal amount of the U.S.
       Physical Securities or the U.S. Global Security, as the case may be, to
       be transferred, and the Trustee shall cancel the Physical Security, if
       any, so transferred or decrease the amount of the U.S. Global Security.

              (d)    Private Placement Legend.  Upon the transfer, exchange or
replacement of Securities not bearing the Private Placement Legend, the
Registrar shall deliver Securities that do not bear the Private Placement
Legend. Upon the transfer, exchange or replacement of Securities bearing the
Private Placement Legend, the Registrar shall deliver only Securities that bear
the Private Placement Legend unless (i) the Private Placement Legend is no
longer required by Section 2.02, (ii) the circumstances contemplated by
paragraph (f)(i)(A) of this Section 2.08 exist or (iii) there is delivered to
the Registrar an Opinion of Counsel reasonably satisfactory to the Company 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.


<PAGE>   40
                                       31



              (e)    General.  By its acceptance of any Security bearing the
Private Placement Legend, each Holder of, or beneficial owner of an interest in,
such Security acknowledges the restrictions on transfer of such Security set
forth in this Indenture and in the Private Placement Legend and agrees that it
will transfer such Security only as provided in this Indenture. The Registrar
shall not register a transfer of any Security unless such transfer complies with
the restrictions on transfer of such Security set forth in this Indenture. In
connection with any transfer of Securities to an Institutional Accredited
Investor, each such Holder or beneficial owner agrees by its acceptance of
Securities to furnish to the Registrar and the Company such certifications,
legal opinions or other information as the Company 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 rely on
a determination made by the Company with respect to) the sufficiency of any such
certifications, legal opinions or other information.

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

              (i)    The Registrar shall register the transfer of any Security,
       whether or not such Security bears the Private Placement Legend, if (A)
       the requested transfer is after the time period referred to in Rule
       144(k) under the Securities Act or any successor provision at the time of
       such transfer or (B) the proposed transferee has delivered to the
       Registrar (1) a certificate substantially in the form of Exhibit D hereto
       and (2) if such transfer is in respect of an aggregate principal amount
       of Securities at the time of transfer of less than $250,000, 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 Security, upon receipt by the
       Registrar of (A) the documents, if any, required by paragraph (i) and (B)
       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 Security in an amount equal to the principal amount of the
       beneficial interest in the U.S. Global Security to be transferred, and
       the Company shall execute, and the Trustee shall authenticate and
       deliver, one or more U.S. Physical Securities of like tenor and amount.

              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 Securities. If a mutilated Security is
surrendered to the Trustee or if the Holder claims that the Security has been
lost, destroyed or wrongfully taken, the Company shall issue and the Trustee
shall authenticate a replacement Security of like tenor and principal amount and
bearing a number not contemporaneously outstanding; provided


<PAGE>   41
                                       32



that the requirements of the second paragraph of Section 2.10 are met. If
required by the Trustee or the Company, an indemnity bond must 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
Security is replaced. The Company may charge such Holder for its expenses and
the expenses of the Trustee in replacing a Security. In case any such mutilated,
lost, destroyed or wrongfully taken Security has become or is about to become
due and payable, the Company in its discretion may pay the principal of,
premium, if any, and interest accrued on such Security instead of issuing a new
Security in replacement thereof.

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

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

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

              If the Paying Agent (other than the Company or an Affiliate of the
Company) holds on the maturity date money sufficient to pay the principal of,
premium, if any, and interest accrued on Securities payable on that date, then
on and after that date such Securities cease to be outstanding and interest on
them shall cease to accrue.

              A Security does not cease to be outstanding because the Company or
one of its Affiliates holds such Security, provided, however, that, in
determining whether the Holders of the requisite principal amount of the
outstanding Securities have given any request, demand, authorization, direction,
notice, consent or waiver hereunder, Securities owned by the Company or any
other obligor upon the Securities or any Affiliate of the Company or of such
other obligor 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
Securities which the Trustee knows to be so owned shall be so disregarded.
Securities 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 Securities and that the pledgee
is not the Company or any other obligor upon the Securities or any Affiliate of
the Company or of such other obligor.

              SECTION 2.11. Temporary Securities. Until definitive Securities
are ready for delivery, the Company may prepare and the Trustee shall
authenticate temporary Securities. Temporary Securities shall be substantially
in the form of definitive Securities but may have insertions, substitutions,
omissions and other variations determined to be appropriate by the Officers
executing the temporary Securities, as evidenced by their execution of such
temporary Securities. If temporary Securities are issued, the Company will cause
definitive Securities to be prepared without unreasonable delay. After the
preparation of definitive Securities, the


<PAGE>   42
                                       33


temporary Securities shall be exchangeable for definitive Securities upon
surrender of the temporary Securities 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 Securities
the Company shall execute and the Trustee shall authenticate and deliver in
exchange therefor a like principal amount of definitive Securities of authorized
denominations. Until so exchanged, the temporary Securities shall be entitled to
the same benefits under this Indenture as definitive Securities.

              SECTION 2.12. Cancellation. The Company at any time may deliver to
the Trustee for cancellation any Securities previously authenticated and
delivered hereunder which the Company may have acquired in any manner
whatsoever, and may deliver to the Trustee for cancellation any Securities
previously authenticated hereunder which the Company has not issued and sold.
The Registrar and the Paying Agent shall forward to the Trustee any Securities
surrendered to them for transfer, exchange or payment. The Trustee shall cancel
all Securities surrendered for transfer, exchange, payment or cancellation and
shall dispose of them in accordance with its normal procedure. The Company shall
not issue new Securities to replace Securities it has paid in full or delivered
to the Trustee for cancellation.

              SECTION 2.13. CUSIP, CINS and ISIN Numbers. The Company in issuing
the Securities may use "CUSIP", "CINS", "ISIN" or other identification numbers
(if then generally in use), and, if so, the Trustee shall use CUSIP numbers,
CINS numbers, ISIN numbers or other identification 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 numbers either as printed on the Securities 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 Securities; provided further, that
failure to use "CUSIP", "CINS", "ISIN" or other identification numbers in any
notice of redemption or exchange shall not effect the validity or sufficiency of
such notice.

              SECTION 2.14. Defaulted Interest. If the Company defaults in a
payment of interest on the Securities, 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 Securities. The Company may,
subject to Article Four of this Indenture and applicable law, issue additional
Securities under this Indenture. The Securities issued on the Closing Date and
any additional Securities subsequently issued shall be treated as a single class
for all purposes under this Indenture.


<PAGE>   43
                                       34



                                  ARTICLE THREE
                                   REDEMPTION


              SECTION 3.01. Right of Redemption. The Securities are redeemable,
in whole or in part, at any time at the Company's option at a redemption price
(the "Make-Whole Price") equal to the greater of (i) 100% of the principal
amount thereof or (ii) as determined by an Independent Investment Banker, the
sum of the present values of the Remaining Scheduled Payments discounted to the
redemption date on a semiannual basis (assuming a 360-day year consisting of
twelve 30-day months) at the Adjusted Treasury Rate, plus, in each case, accrued
and unpaid interest (including Additional Interest, as provided for in the
Registration Rights Agreement), if any, to the date of redemption.

              "Adjusted Treasury Rate" means with respect to any redemption
date, the rate per annum equal to the semiannual equivalent yield to maturity of
the Comparable Treasury Issue, assuming a price for the Comparable Treasury
Issue (expressed as a percentage of its principal amount) equal to the
Comparable Treasury Price for such redemption date, plus 0.50%.

              "Comparable Treasury Issue" means the United States Treasury
Security selected by an Independent Investment Banker as having a maturity
comparable to the remaining term of the Securities that would be utilized, at
the time of selection and in accordance with customary financial practice, in
pricing new issues of corporate debt securities of comparable maturity to the
remaining term of the Securities.

              "Comparable Treasury Price" means, the respect to any redemption
date, (i) the average of the bid and asked prices for the Comparable Treasury
Issue (expressed in each case as a percentage of its principal amount) on the
third Business Day preceding such redemption date, as set forth in the daily
statistical release (or any successor release) published by the Federal Reserve
Bank of New York and designated "Composite 3:30 p.m. Quotations for U.S.
Government Securities" or (ii) if such release (or any successor release) is not
published or does not contain such prices on such Business Day, (A) the
Reference Treasury Dealer Quotations for such redemption date, after excluding
the highest and lowest of such Reference Treasury Dealer Quotations, or (B) if
the Trustee obtains fewer than three such Reference Treasury Dealer Quotations,
the average of all such Quotations.

              "Independent Investment Banker" means any Reference Treasury
Dealer appointed by the Trustee after consultation with the Company.

              "Reference Treasury Dealer" means each of Morgan Stanley & Co.
Incorporated, Chase Securities Inc., First Union Capital Markets, a division of
Wheat First Securities, Inc., NationsBanc Montgomery Securities LLC and TD
Securities (USA) Inc. and their respective successors; provided, however, that
if any of the foregoing shall case to be a primary U.S. Government securities
dealer in New York City (a "Primary Treasury Dealer"), the Company shall
substitute another Primary Treasury Dealer and shall deliver written notice of
such substitution to the Trustee.


<PAGE>   44
                                       35



              "Reference Treasury Dealer Quotations" means, with respect to each
Reference Treasury Dealer and any redemption date, the average as determined by
the Trustee, of the bid and asked prices of the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) quoted in
writing to the Trustee by such Reference Treasury Dealer at 5:00 p.m. on the
third Business Day preceding such redemption date.

              "Remaining Scheduled Payments" means, with respect to each
Security to be redeemed, the remaining scheduled payments of the principal
thereof and interest thereon that would be due after the related redemption date
but for such redemption; provided, however, that, if such redemption date is not
an interest payment date with respect to such Security, the amount of the next
succeeding scheduled interest payment thereon will be reduced by the amount of
interest accrued and unpaid thereon to such redemption date.

              In addition, at any time prior to February 16, 2003, the Company
may redeem up to 35% of the principal amount of the Securities originally issued
with the Net Cash Proceeds (other than proceeds from the exercise of the
over-allotment option by the underwriters in connection with the Company's
initial public offering) of one or more public or private issuances of Capital
Stock (other than Disqualified Stock) at any time or from time to time in part,
at a Redemption Price of 113.750%of the principal amount thereof on the
Redemption Date, together with accrued and unpaid interest, if any, thereon;
provided that (i) at least 65% of the principal amount of the Securities remain
outstanding after each such redemption and (ii) notice of such redemption is
mailed within 60 days of such issuance.

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

              The Company shall give each notice provided for in this Section
3.02 in an Officers' Certificate at least ten days before mailing the notice to
Holders required pursuant to Section 3.04 (unless a shorter period shall be
satisfactory to the Trustee).

              SECTION 3.03. Selection of Securities to Be Redeemed. In the case
of any partial redemption, selection of the Securities for redemption will be
made by the Trustee in compliance with the requirements of the principal
national securities exchange, if any, on which the Securities are listed or, if
the Securities are not listed on a national securities exchange, by lot or by
such other method as the Trustee in its sole discretion shall deem to be fair
and appropriate; provided that no Security of $1,000 in principal amount or less
shall be redeemed in part.

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


<PAGE>   45
                                       36



Trustee shall notify the Company and the Registrar promptly in writing of the
Securities or portions of Securities to be called for redemption.

              SECTION 3.04. Notice of Redemption. With respect to any redemption
of Securities pursuant to Section 3.01, 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 Securities are to be redeemed.

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

              (a)    the Redemption Date;

              (b)    the Redemption Price;

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

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

              (e)    that, unless the Company defaults in making the redemption
       payment, interest on Securities 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 Securities to the Paying Agent;

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

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

              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 ten days before
it is required to mail the notice to Holders required by this Section 3.04, the
Trustee shall give such 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.


<PAGE>   46
                                       37



              SECTION 3.05. Effect of Notice of Redemption. Once notice of
redemption is mailed, Securities called for redemption become due and payable on
the Redemption Date and at the Redemption Price. Upon surrender of any
Securities to the Paying Agent, such Securities 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 Securities held by Holders to whom such notice
was properly given.

              SECTION 3.06. Deposit of Redemption Price. On or prior to 10:00
A.M. on 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 Securities to be redeemed on that date
other than Securities or portions thereof called for redemption on that date
that have been delivered by the Company to the Trustee for cancellation.

              SECTION 3.07. Payment of Securities Called for Redemption. If
notice of redemption has been given in the manner provided above, the Securities
or portion of Securities 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 Securities 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 Securities), such Securities shall cease to accrue interest.
Upon surrender of any Security for redemption in accordance with a notice of
redemption, such Security 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 shall be payable to the Holders
registered as such at the close of business on the relevant Regular Record Date
that is on or prior to the Redemption Date.

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


                                  ARTICLE FOUR
                                    COVENANTS

              SECTION 4.01. Payment of Securities. The Company shall pay the
principal of, premium, if any, and interest on the Securities on the dates and
in the manner provided in the Securities 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


<PAGE>   47
                                       38


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 for the Securities.

              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 Securities.

              SECTION 4.02. Maintenance of Offices or Agencies. The Company will
maintain in the Borough of Manhattan, The City of New York, an office or agency
(which may be an office of the Trustee, Registrar or co-Registrar or any
Affiliate of any of them) where Securities may be surrendered for registration
of transfer or exchange or for presentation for payment and where notices and
demands to or upon the Company in respect of the Securities and this Indenture
may be served. In addition, so long as the Securities are listed on the
Luxembourg Stock Exchange and the Luxembourg Stock Exchange so requires, there
will be a Paying Agent and transfer agent in Luxembourg where Securities may be
presented for registration of transfer or for exchange and where Securities may
be presented for payment. The Company will give prompt written notice to the
Trustee of the location, and any change in the location, of such offices or
agencies. 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 10.02.

              The Company may also from time to time designate one or more other
offices or agencies where the Securities may be presented or surrendered for any
or all such purposes and may from time to time rescind such designations. 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, and
the office of Banque Internationale a Luxembourg, located at 69 route d'Esch,
L-1470 Luxembourg, Luxembourg, as such offices 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 Securities
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
Indebtedness to EBITDA Ratio would be greater than zero and less than 4:1.


<PAGE>   48
                                       39


              Notwithstanding the foregoing, the Company and any Restricted
Subsidiary (except as specified below) may Incur each and all of the following:
(i) Indebtedness outstanding at any time in an aggregate principal amount not to
exceed the greater of (A) $200 million or (B) the Consolidated EBITDA for the
four preceding 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 Indebtedness permanently repaid as provided
under Section 4.11 (other than any Securities permanently repaid); provided that
no more than 25% of the Indebtedness Incurred under this clause (i) may be used
for purposes other than capital expenditures; (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) 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 (ii), (vi), (viii) or (x) 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 Securities or Indebtedness that is pari passu with, or subordinated in right
of payment to, the Securities shall only be permitted under this clause (iii) if
(A) in case the Securities are refinanced in part or the Indebtedness to be
refinanced is pari passu with the Securities, 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 Securities, (B) in case the Indebtedness
to be refinanced is subordinated in right of payment to the Securities, 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 Securities at least to the
extent that the Indebtedness to be refinanced is subordinated to the Securities
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,



<PAGE>   49
                                       40


assets or Restricted Subsidiary for the purpose of financing such acquisition),
in a principal amount not to exceed the gross proceeds actually received by the
Company or any Restricted Subsidiary in connection with such disposition; (v)
Indebtedness of the Company, to the extent the net proceeds thereof are promptly
(A) used to purchase Securities tendered in an Offer to Purchase made as a
result of a Change in Control or (B) deposited to defease the Securities as
described below under Article Eight; (vi) Guarantees of the Securities 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 4.07; (vii) Indebtedness (including Guarantees) Incurred to finance the
cost (including the cost of design, development, acquisition, construction,
installation, improvement, transportation or integration) to acquire equipment,
inventory or network assets (including acquisitions by way of Capitalized Lease
and acquisitions of the Capital Stock of a Person that becomes a Restricted
Subsidiary to the extent of the fair market value of the equipment, inventory or
network assets so acquired) by the Company or a Restricted Subsidiary after the
Closing Date; (viii) Indebtedness of the Company not to exceed, at any one time
outstanding, two times the sum of (A) the Net Cash Proceeds received by the
Company after June 17, 1998 as a capital contribution or from the issuance and
sale of its Capital Stock (other than Disqualified Stock) to a Person that is
not a Subsidiary of the Company, to the extent (I) such capital contribution or
Net Cash Proceeds are not, at the Company's option, added to the amount
calculated pursuant to clause (C)(2) of the first paragraph of Section 4.04 or
used to make a Restricted Payment pursuant to clause (iii), (iv) or (viii) of
the second paragraph of Section 4.04 and (II) if such capital contribution or
Net Cash Proceeds are used to consummate a transaction pursuant to which the
Company Incurs Acquired Indebtedness, the amount of such Net Cash Proceeds
exceeds one-half of the amount of Acquired Indebtedness so Incurred 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 Disqualified Stock) to a Person that is not a Subsidiary of
the Company, to the extent (I) such capital contribution or sale of Capital
Stock has not been used to make a Restricted Payment pursuant to clause (iii),
(iv) or (viii) of the second paragraph of Section 4.04 and (II) if such capital
contribution or Capital Stock is used to consummate a transaction pursuant to
which the Company Incurs Acquired Indebtedness, 80% of the fair market value of
the property received exceeds one-half of the amount of Acquired Indebtedness so
Incurred; provided that such Indebtedness does not mature prior to the Stated
Maturity of the Securities and has an Average Life longer than the Securities;
(ix) Acquired Indebtedness; (x) Strategic Subordinated Indebtedness; (xi)
Indebtedness consisting of one or more loans to any Restricted Subsidiary,
evidenced by one or more Promissory Notes and Guaranteed by the Company, in each
case under the Intermediary Documents; provided that the Promissory Notes shall,
at all times, have an aggregate principal amount equal to the aggregate
principal amount of the Certificates of Deposit and shall not be outstanding at
any time that the Certificates of Deposit are not validly outstanding and
beneficially owned by the Company; (xii) Indebtedness of any Restricted
Subsidiary, to the extent that the Company is the beneficial owner of such
Indebtedness and such Indebtedness is evidenced by a promissory note or
participation certificate issued to the Company by the record holder of such
Indebtedness; (xiii) Indebtedness of the Company, the proceeds of which are used
to make an Investment in Intelsat, in an amount at any one time outstanding not
to exceed $30 million; provided that the Company reasonably believes, at the
time such Indebtedness is Incurred, that the benefits of such Investment will
result in cash


<PAGE>   50
                                       41


flow sufficient to cover the payment of interest and principal on such
Indebtedness and (xiv) subordinated Indebtedness of the Company (in addition to
Indebtedness permitted under clauses (i) through (xiii) above) in an aggregate
principal amount outstanding at any time not to exceed $100 million, less any
amount of such Indebtedness permanently repaid as provided under Section 4.11.

              (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 4.09
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, and from time to
time may reclassify, 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 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 held by Persons other than the Company or any Restricted
Subsidiary (other than (x) dividends or distributions payable solely in shares
of its or such Restricted Subsidiary's Capital Stock (other than Disqualified
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), (ii) purchase, redeem, retire or otherwise acquire for value any
shares of Capital Stock of the Company (including options, warrants or other
rights to acquire such shares of Capital Stock) held by Persons other than the
Company or any of its Wholly-Owned Restricted Subsidiaries, (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
Securities 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) above 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
or (C) the aggregate amount of 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


<PAGE>   51
                                       42


period (taken as one accounting period) beginning on the first day of the fiscal
quarter commencing July 1, 1998 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 received by the Company after June 17, 1998 as a
capital contribution or from the issuance and sale of its Capital Stock (other
than Disqualified 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 Disqualified 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 convertible indebtedness, Disqualified 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
Securities), in each case except to the extent such Net Cash Proceeds are used
to Incur Indebtedness pursuant to clause (viii) of the second paragraph under
Section 4.03, plus (3) an amount equal to the net reduction in Investments made
pursuant to this first paragraph of this Section 4.04 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 Securities 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 part (a) of Section 4.03; (iii) the repurchase,
redemption or other acquisition of Capital Stock of the Company (or options,
warrants or other rights to acquire such Capital Stock) in exchange for, or out
of the proceeds of a capital contribution or a substantially concurrent offering
of, shares of Capital Stock (other than Disqualified 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 Securities in exchange for, or out of
the proceeds of a capital contribution or a substantially concurrent offering
of, shares of the Capital Stock (other than Disqualified 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 Article Five; (vi) Investments in Unrestricted
Subsidiaries not to exceed, at any one time outstanding, the greater of (A) $5
million or (B) 10% of Consolidated EBITDA for the preceding four quarters for
which reports have been filed pursuant to Section 4.18; (vii) Investments in any
Person the primary business of


<PAGE>   52
                                       43


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 (vii) does not
exceed $20 million; (viii) Investments acquired in exchange for Capital Stock
(other than Disqualified Stock) of the Company or with the proceeds of such
Capital Stock; provided that such proceeds are so applied within 90 days of
receipt thereof; (ix) 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; and (x) other Restricted Payments in an aggregate amount
not to exceed $25 million; 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. The value
of any Restricted Payment made other than in cash shall be the fair market value
thereof. The amount of any Investment "outstanding" at any time shall be deemed
to be equal to the amount of such Investment on the date made, less the return
of capital to the Company and its Restricted Subsidiaries with respect to such
Investment (up to the amount of such Investment).

              Each Restricted Payment permitted pursuant to the preceding
paragraph (other than the Restricted Payment referred to in clause (ii) thereof,
an exchange of Capital Stock for Capital Stock or Indebtedness referred to in
clause (iii) or (iv) thereof and an Investment referred to in clause (vi)
thereof), and the Net Cash Proceeds from any capital contribution or any
issuance of Capital Stock referred to in clauses (iii), (iv) and (viii), shall
be included in calculating whether the conditions of clause (C) of the first
paragraph of this Section 4.04 have been met with respect to any subsequent
Restricted Payments. If the proceeds of an issuance of Capital Stock of the
Company are used for the redemption, repurchase or other acquisition of the
Securities, or Indebtedness that is pari passu with the Securities, then the Net
Cash Proceeds of such issuance shall be included in clause (C) of the first
paragraph of this Section 4.04 only to the extent such proceeds are not used for
such redemption, repurchase or other acquisition of Indebtedness. For purposes
of determining compliance with this Section 4.04, in the event that a Restricted
Payment meets the criteria of more than one of the types of Restricted Payments
described in clauses (i) through (x) of the preceding paragraph, the Company, in
its sole discretion, shall classify such Restricted Payment and only be required
to include the amount and type of such Restricted Payment in one of such
clauses.

              SECTION 4.05. 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 or any other agreements in effect
on the Closing Date, and any


<PAGE>   53
                                       44


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 4.05, (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, 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 during
the period between the execution of such agreement and the closing thereunder
within three months of such execution; (vi) with respect to Restricted
Subsidiaries in which, on and subsequent to the Closing Date, the Company and
other Restricted Subsidiaries only make Investments that are evidenced by
unsubordinated promissory notes that bear a reasonable rate of interest and are
payable prior to the Stated Maturity of the Securities; provided that such
encumbrances and restrictions expressly allow the payment of interest and
principal on such promissory notes; (vii) encumbrances or restrictions solely of
the type referred to in clause (iii) or (iv) of the preceding paragraph that are
contained in any stockholders' agreement, joint venture agreement or similar
agreement among owners of Common Stock of a Restricted Subsidiary; provided that
such restrictions consist solely of requirements that transactions between such
Restricted Subsidiaries and affiliates thereof (including the Company and its
Restricted Subsidiaries) be on fair and reasonable terms no less favorable to
such Restricted Subsidiary than could be obtained in a comparable arm's-length
transaction with a Person that is not such an affiliate; or (viii) 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 Securities 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
Securities. Nothing contained in this Section 4.05 shall prevent the Company or
any Restricted Subsidiary from (1) creating, incurring, assuming or suffering to
exist any Liens otherwise permitted in Section 4.09 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.


<PAGE>   54
                                       45


              SECTION 4.06. 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 4.04 if made on the date of such
issuance or sale; or (iv) the sale of Common Stock of Restricted Subsidiaries
that is not Disqualified Stock, if the proceeds of such issuance or sale are
applied in accordance with clause (A) or (B) of the first paragraph of Section
4.11 or (v) the transfer of up to 3% of the Common Stock of each Restricted
Subsidiary to employees of such Restricted Subsidiary in connection with such
employment.

              SECTION 4.07. 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 Securities ("Guaranteed
Indebtedness"), unless (i) such Restricted Subsidiary simultaneously executes
and delivers a supplemental indenture to this Indenture providing for a
Guarantee (a "Subsidiary Guarantee") of payment of the Securities 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
Securities, then the Guarantee of such Guaranteed Indebtedness shall be pari
passu with, or subordinated to, the Subsidiary Guarantee or (B) subordinated to
the Securities, 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 Securities.

              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 this 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 4.08. Limitation on Transactions with Shareholders and
Affiliates. The Company will not, and will not permit any Restricted Subsidiary
to, directly or indirectly,


<PAGE>   55
                                       46


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 U.S.
investment banking firm stating that the transaction is fair to the Company or
such Restricted Subsidiary from a financial point of view; (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; or (v) any Restricted Payments not
prohibited by Section 4.04 (other than pursuant to clause (iv) of the definition
or "Permitted Investment"). Notwithstanding the foregoing, any transaction or
series of related transactions covered by the first paragraph of this Section
4.08 and not covered by clauses (ii) through (v) of this paragraph, the
aggregate amount of which exceeds $1 million in value, must be approved or
determined to be fair in the manner provided for in clause (i)(A) or (B) above.

              SECTION 4.09. Limitation on Liens. The Company will not, and will
not permit any Restricted Subsidiary to, create, incur, assume or suffer to
exist any Lien on any of its assets or properties of any character (including,
without limitation, licenses), or any shares of Capital Stock or Indebtedness of
any Restricted Subsidiary, without making effective provision for all of the
Securities and all other amounts due under this Indenture to be directly secured
equally and ratably with (or, if the obligation or liability to be secured by
such Lien is subordinated in right of payment to the Securities, prior to) the
obligation or liability secured by such Lien.

              The foregoing limitation does not apply to (i) Liens existing on
the Closing Date; (ii) Liens granted after the Closing Date on any assets or
Capital Stock of the Company or its Restricted Subsidiaries created in favor of
the Holders; (iii) Liens with respect to the assets of a Restricted Subsidiary
granted by such Restricted Subsidiary to the Company or a Wholly-Owned
Restricted Subsidiary to secure Indebtedness owing to the Company or such other
Restricted Subsidiary; (iv) Liens securing Indebtedness which is Incurred to
refinance secured Indebtedness which is permitted to be Incurred under clause
(iii) of the second paragraph of Section 4.03; provided that such Liens do not
extend to or cover any property or assets of the Company or any Restricted
Subsidiary other than the property or assets securing the Indebtedness being
refinanced; (v) Liens on the Capital Stock of, or any property or assets of, a
Restricted Subsidiary securing Indebtedness of such Restricted Subsidiary
permitted under Section 4.03;


<PAGE>   56
                                       47


(vi) Liens on the Capital Stock of Restricted Subsidiaries securing up to $100.0
million of Indebtedness Incurred under clause (vii) of the second paragraph of
Section 4.03(a); (vii) Liens on assets having a fair market value equal to no
more than 10% of the fair market value of the Adjusted Consolidated Net Tangible
Assets that are not subject to Liens on the Closing Date; or (viii) Permitted
Liens.

              SECTION 4.10. Limitation on Sale-Leaseback Transactions. The
Company will not, and will not permit any Restricted Subsidiary to, enter into
any sale-leaseback transaction involving any of its assets or properties whether
now owned or hereafter acquired, whereby the Company or a Restricted Subsidiary
sells or transfers such assets or properties and then or thereafter leases such
assets or properties or any part thereof or any other assets or properties which
the Company or such Restricted Subsidiary, as the case may be, intends to use
for substantially the same purpose or purposes as the assets or properties sold
or transferred.

              The foregoing restriction does not apply to any sale-leaseback
transaction if (i) the lease is for a period, including renewal rights, of not
in excess of three years; (ii) the lease secures or relates to industrial
revenue or pollution control bonds; (iii) the transaction is solely between the
Company and any Wholly-Owned Restricted Subsidiary or solely between
Wholly-Owned Restricted Subsidiaries; or (iv) the Company or such Restricted
Subsidiary, within 12 months after the sale or transfer of any assets or
properties is completed, applies an amount not less than the net proceeds
received from such sale in accordance with clause (A) or (B) of the first
paragraph of Section 4.11.

              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; provided, however, that this clause (ii) shall not apply to
long-term assignments in capacity in a telecommunications network. 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 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 (i) 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 unsubordinated
Indebtedness of the Company, or any Restricted Subsidiary providing a Subsidiary
Guarantee pursuant to Section 4.07 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


<PAGE>   57
                                       48


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 (ii)
apply (no later than the end of the 12-month period referred to in clause (i))
such excess Net Cash Proceeds (to the extent not applied pursuant to clause (i))
as provided in the following paragraph 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 (i) 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 $5 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 principal amount of Securities equal to the Excess Proceeds on such
date, at a purchase price equal to 101% of the principal amount of the
Securities, plus accrued interest (if any) to the Payment Date.

              SECTION 4.12. Repurchase of Securities upon a Change of Control.
The Company must commence, within 30 days of the occurrence of a Change of
Control, and consummate an Offer to Purchase for all Securities then
outstanding, at a purchase price equal to 101% of the principal amount of the
Securities on the relevant Payment Date, plus accrued interest (if any) to the
Payment Date. Prior to the mailing of the notice to Holders commencing such
Offer to Purchase, but in any event within 30 days following any Change of
Control, the Company covenants to (i) repay in full all indebtedness of the
Company that would prohibit the repurchase of the Securities pursuant to such
Offer to Purchase or (ii) obtain any requisite consents under instruments
governing any such indebtedness of the Company to permit the repurchase of the
Securities. The Company shall first comply with the covenant in the preceding
sentence before it shall be required to repurchase Securities pursuant to this
Section 4.12.

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

              SECTION 4.14. Payment of Taxes and Other Claims. The Company shall
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


<PAGE>   58
                                       49


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
shall 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
Restricted Subsidiary from discontinuing the use, operation or maintenance of
any of such properties or disposing on 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 Restricted Subsidiary.

              The Company shall 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, shall give written notice thereof to the Trustee.

              SECTION 4.17. Compliance Certificates. (a) The Company shall
deliver to the Trustee, within 90 days after the end of the Company's fiscal
year, an Officers' Certificate stating whether or not the signers know of any
Default or Event of Default that occurred during such fiscal year. Such
certificates shall contain a certification from the principal executive officer,
principal financial officer or principal accounting officer of the Company that
a review has been conducted of the activities of the Company and the Restricted
Subsidiaries and the Company's and the Restricted Subsidiaries' performance
under this Indenture and that, to the best knowledge of such officer, 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 any such officer knows of such a Default or Event of Default, the
certificate shall describe any such Default or Event of Default and its status.


<PAGE>   59
                                       50


              (b)    The Company shall deliver to the Trustee, within 90 days
after the end of its 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
Securities 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 required to file reports with the Commission, if any
Securities are outstanding, 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, unless the Company shall be unable to effect such filing or the
Commission shall refuse to accept such filing. The Company shall supply the
Trustee and each Holder of Securities or shall supply to the Trustee for
forwarding to each such Holder, without cost to such Holder, copies of such
reports and other information, whether or not the Company shall be unable to
effect such filing or the Commission refuses to accept such filing. For so long
as the Securities are listed on the Luxembourg Stock Exchange, the Company shall
supply to the Paying Agent in Luxembourg copies of all such reports and
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 Securities 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.


<PAGE>   60
                                       51


                                  ARTICLE FIVE
                              SUCCESSOR CORPORATION

              SECTION 5.01. When Company May Merge, Etc. The Company will 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 (other than 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 Common Stock in the surviving Person or the Company) shall be issued or
distributed to the stockholders of the Company) 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 Securities and
hereunder; (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, the Company or any
Person becoming the successor obligor of the Securities shall have a
Consolidated Net Worth equal to or greater than the Consolidated Net Worth of
the Company immediately prior to such transaction; (iv) immediately after giving
effect to such transaction on a pro forma basis the Company, or any Person
becoming the successor obligor of the Securities, as the case may be, could
Incur at least $1.00 of Indebtedness under the first paragraph of Section 4.03;
provided that this clause (iv) shall not apply to (x) a consolidation, merger or
sale of all (but not less than all) of the assets of the Company if all Liens
and Indebtedness of the Company or any Person becoming the successor obligor of
the Securities, as the case may be, and its Restricted Subsidiaries outstanding
immediately after such transaction would, if Incurred at such time, have been
permitted to be Incurred (and all such Liens and Indebtedness, other than Liens
and Indebtedness of the Company and its Restricted Subsidiaries outstanding
immediately prior to the transaction, shall be deemed to have been Incurred) for
all purposes of this Indenture or (y) a consolidation, merger or sale of all or
substantially all of the assets of the Company if immediately after giving
effect to such transaction on a pro forma basis, the Company or any Person
becoming the successor obligor of the Securities shall have an Indebtedness to
EBITDA Ratio equal to or less than the Indebtedness to EBITDA Ratio of the
Company immediately prior to such transaction; and (v) the Company delivers to
the Trustee an Officers' Certificate (attaching the arithmetic computations to
demonstrate compliance with clauses (iii) and (iv) above) 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 clauses (iii) and (iv) above do 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
provided further that any such transaction shall not have as one of its purposes
the evasion of the foregoing limitations.


<PAGE>   61
                                       52


              SECTION 5.02. Successor Substituted. Upon any consolidation or
merger, or any sale, conveyance, transfer 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 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; provided that the Company shall not be released from its
obligations to pay the principal of, premium, if any, or interest on the
Securities in the case of a lease of all or substantially all of its property
and assets.

                                   ARTICLE SIX
                              DEFAULT AND REMEDIES


              SECTION 6.01. Events of Default. Any of the following events shall
constitute an Event of Default:

              (a)    default in the payment of principal of (or premium, if any,
       on) any Security when the same becomes due and payable at maturity, upon
       acceleration, redemption or otherwise;

              (b)    default in the payment of interest on any Security when the
       same becomes due and payable, and such default continues for a period of
       30 days;

              (c)    the Company defaults in the performance of or breaches any
       other covenant or agreement of the Company in this Indenture or under the
       Securities 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 Securities;

              (d)    there occurs with respect to any issue or issues of
       Indebtedness of the Company or any Significant Subsidiary having an
       outstanding principal amount of $5 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;

              (e)    any final judgment or order (not covered by insurance) for
       the payment of money in excess of $5 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


<PAGE>   62
                                       53


       not be paid or discharged, and either (A) an enforcement proceeding shall
       have been commenced by a creditor upon such judgment or order or (B)
       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 $5 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;

              (f)    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 30 consecutive days; or

              (g)    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 (f) or (g) 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
Securities, 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 principal of, premium, if any, and
accrued interest on the Securities to be immediately due and payable. Upon a
declaration of acceleration, such principal of, premium, if any, and accrued
interest shall be immediately due and payable. In the event of a declaration of
acceleration because an Event of Default set forth in clause (d) 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 (d) of Section 6.01 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, and no other Defaults under this Indenture
have occurred and are continuing after giving pro forma effect to such remedy,
cure or waiver. If an Event of Default specified in clause (f) or (g) of Section
6.01 occurs with respect to the Company, the principal of, premium, if any, and
accrued interest on the Securities 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.


<PAGE>   63
                                       54



              At any time after such 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 Securities, by written notice to the Company and to the Trustee, may
waive all past Defaults and rescind and annul a declaration of acceleration and
its consequences if (a) the Company has paid or deposited 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 Securities, (iii) the
principal of and premium, if any, on any Securities that have become due
otherwise than by such declaration or occurrence of acceleration and interest
thereon at the rate prescribed therefor by such Securities, and (iv) to the
extent that payment of such interest is lawful, interest upon overdue interest,
if any, at the rate prescribed therefor by such Securities, (b) all existing
Events of Default, other than the non-payment of the principal of, premium, if
any, and accrued interest on the Securities that have become due solely by such
declaration of acceleration have been cured or waived as provided in Section
6.04 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 Securities or to enforce the performance of any provision of the
Securities or this Indenture.

              The Trustee may maintain a proceeding even if it does not possess
any of the Securities 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 Securities, by notice to the Trustee, may waive all existing
Defaults and Events of Default and its consequences, except a Default in the
payment of principal of, premium, if any, or interest on any Security 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 Security 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 Securities may,
subject to Section 7.02(iv), 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. However, 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 of Securities not joining in the
giving of such direction and may take any other action it deems proper that is
not inconsistent with any direction received from Holders of Securities pursuant
to this Section 6.05.


<PAGE>   64
                                       55



              SECTION 6.06. Limitation on Suits.  A Holder may not pursue any
                                                  remedy with respect to this
                                                  Indenture or the Securities
                                                  unless:

              (i)    the Holder gives the Trustee written notice of a continuing
       Event of Default;

              (ii)   the Holders of at least 25% in aggregate principal amount
       of outstanding Securities make a written request to the Trustee to pursue
       the remedy;

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

              (iv)   the Trustee does not comply with the request within 60 days
       after receipt of the written request and the offer of indemnity; and

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

              For purposes of Section 6.05 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 Securities
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
Securities 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 Security to receive payment of the principal of, premium, if any, or
interest on such Security, or to bring suit for the enforcement of any such
payment, on or after the due date expressed in such Security, 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) or (b) of
Section 6.01 occurs and is continuing, the Trustee may recover judgment in its
own name and as trustee of an express trust against the Company or any other
obligor of the Securities 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 Securities, and such further amount as shall be sufficient to
cover the costs and expenses of collection, including the


<PAGE>   65
                                       56


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 Securities), 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 Securities 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 Securities 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 the Holders for amounts then due and unpaid for
       principal of, premium, if any, and interest on the Securities 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 Securities for principal, premium, if
       any, and interest, respectively; and

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

              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


<PAGE>   66
                                       57


suit by the Trustee, a suit by a Holder pursuant to Section 6.07, or a suit by
Holders of more than 10% in principal amount of the outstanding Securities.

              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 Securities 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.

                                  ARTICLE SEVEN
                               TRUSTEE AND AGENTS

              SECTION 7.01. General. The duties and responsibilities of the
Trustee shall be as provided by the TIA and as set forth herein. Whether or not
herein 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. Subject to TIA Sections 315(a)
through (d):

              (i)    the Trustee and each Agent 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 and each Agent need
       not


<PAGE>   67
                                       58


       investigate any fact or matter stated in the document and may in good
       faith conclusively rely as to the truth of the statements and the
       correctness of the opinions therein;

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

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

              (iv)   the Trustee and each Agent 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 and such Agent security or indemnity
       reasonably satisfactory to it 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 of the outstanding Securities relating to the time, method and
       place of conducting any proceeding for any remedy available to the
       Trustee, or exercising any trust or power conferred upon the Trustee,
       under this Indenture; provided that the Trustee's conduct does not
       constitute negligence or bad faith;

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

              (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;
       and

              (viii) any request or direction of the Company mentioned herein
       shall be sufficiently evidenced by a Company Order and any resolution of
       the Board of Directors may be sufficiently evidenced by a Board
       Resolution.


<PAGE>   68
                                       59



              SECTION 7.03. Individual Rights of Trustee. The Trustee, in its
individual or any other capacity, may become the owner or pledgee of Securities
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
Securities, (ii) shall not be accountable for the Company's use or application
of the proceeds from the Securities and (iii) shall not be responsible for any
statement in the Securities 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 an officer assigned to administer corporate trust matters of 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 Security, 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.

              SECTION 7.06. Reports by Trustee to Holders. Within 60 days after
each May 15, beginning with May 15, 2000, the Trustee shall mail to each Holder
as provided in TIA Section 313(c) a brief report that complies with TIA Section
313(a) dated as of such May 15, if required by TIA Section 313(a).

              A copy of each report at the time of its mailing to the Holders of
Securities shall be mailed to the Company and filed with the Commission and each
stock exchange on which the Securities are listed in accordance with TIA Section
313(d). The Company shall promptly notify the Trustee when the Securities are
listed on any stock exchange or of any delisting thereof.

              SECTION 7.07. Compensation and Indemnity. The Company shall pay to
the Trustee from time to time 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
(including costs of collection) 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 Securities,
including, without limitation, the costs and expenses of investigating or
defending itself against any claim or liability and of complying with any
process served upon it or any of its


<PAGE>   69
                                       60


officers in connection with the exercise or performance of any of its powers or
duties under this Indenture and the Securities.

              To secure the Company's payment obligations in this Section 7.07,
the Trustee shall have a lien prior to the Securities 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 Securities.

              If the Trustee incurs expenses or renders services after the
occurrence of an Event of Default specified in clause (f) or (g) 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 Securities 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 if: (i) the Trustee is no longer eligible under Section
7.10; (ii) the Trustee is adjudged a bankrupt or an insolvent; (iii) a receiver
or other public officer takes charge of the Trustee or its property; or (iv) the
Trustee becomes incapable of acting.

              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 Securities 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
Securities 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.


<PAGE>   70
                                       61



              If the Trustee is no longer eligible under Section 7.10 or shall
fail to comply with TIA Section 310(b), 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 obligations under Section 7.07 shall continue
indefinitely for the benefit of the retiring Trustee.

              SECTION 7.09. Successor Trustee by Merger, Etc. If the Trustee or
any Agent 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 or Agent with the same effect as if the successor Trustee or Agent had
been named as the Trustee or Agent herein, provided such corporation shall be
otherwise qualified and eligible under this Article.

              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.

              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 in
writing 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 Securities any and all withholding
taxes applicable thereto as required by the federal law of the United States or
the law of the State of New York or any political subdivision thereof ("U.S.
Taxes"). The Trustee agrees to act as such withholding agent and, in connection
therewith, whenever any present or future U.S. Taxes or similar charges are
required to be withheld with respect to any amounts payable in respect of the
Securities, 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 Securities, 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 Security appropriate documentation showing the payment thereof,
together with such additional documentary evidence as such holders may
reasonably request from time to time.


<PAGE>   71
                                       62


                                  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 Securities and this Indenture if:

              (i)    all Securities previously authenticated and delivered
       (other than destroyed, lost or stolen Securities that have been replaced
       or Securities that are paid pursuant to Section 4.01 or Securities 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 Securities 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, premium, if, any,
       and interest on the Securities 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 Securities 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 Securities 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 Securities 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 Securities on the 123rd day or, to the extent applicable under
clause (B) below, one year after the date of the deposit referred to in clause
(A) of this Section 8.02, and the provisions of this


<PAGE>   72
                                       63


Indenture will no longer be in effect with respect to the Securities, and the
Trustee, at the expense of the Company, shall execute proper instruments
acknowledging the same if:

              (A)    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
       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 Securities, 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 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 Securities 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 Securities;

              (B)    the Company shall have delivered to the Trustee (i) either
       (x) an Opinion of Counsel to the effect that Holders will not recognize
       income, gain or loss for United States 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 United States 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, which Opinion of Counsel
       must be based upon (and accompanied by a copy of) a ruling of the United
       States Internal Revenue Service to the same effect unless there has been
       a change in applicable United States federal income tax law after the
       Closing Date such that a ruling is no longer required or (y) a ruling
       directed to the Trustee received from the United States Internal Revenue
       Service to the same effect as the aforementioned Opinion of Counsel; and
       (ii) 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


<PAGE>   73
                                       64


       to rule under any such law in any case or proceeding that the trust funds
       remained property of the Company (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), (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 and (c) 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;

              (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 (or one year) after the date of such deposit, and such deposit
       shall not result in a breach or violation of, or constitute a default
       under, any other agreement or instrument to which the Company or any of
       its Subsidiaries is a party or by which the Company or any of its
       Subsidiaries is bound;

              (D)    if the Securities are then listed on a national securities
       exchange, the Company shall have delivered to the Trustee an Opinion of
       Counsel to the effect that the Securities will not be delisted as a
       result of such deposit, defeasance and discharge; 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 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 (B)(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, 8.04, 8.05 and 8.06 shall survive until the
Securities are no longer outstanding. Thereafter, only the Company's obligations
in Sections 7.07, 8.04, 8.05 and 8.06 shall survive. If and when a ruling from
the United States Internal Revenue Service or an Opinion of Counsel referred to
in clause (B)(i) of this Section 8.02 may 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
Securities and this Indenture except for those surviving obligations in the
immediately preceding paragraph.


<PAGE>   74
                                       65



              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 4.11, and clause (c) of
Section 6.01 with respect to clauses (iii) and (iv) of Section 5.01 and clauses
(d) and (e) of Section 6.01 shall be deemed not to be Events of Default, in each
case with respect to the outstanding Securities if:

              (i)    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 Securities, 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 Securities 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 Securities;

              (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 or any of its Subsidiaries 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 United States federal
       income tax purposes as a result of such deposit and the defeasance of the
       obligations referred to in the first paragraph of this Section 8.03 and
       will be subject to United States 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
       "insider" for purposes of the United States Bankruptcy Code, after one
       year following the deposit), the


<PAGE>   75
                                       66


       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 the 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)    if the Securities 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 and defeasance will not cause the
       Securities to be delisted; and

              (vi)   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 Securities and this Indenture to
the payment of principal of, premium, if any, and interest on the Securities;
but such money need not be segregated from other funds except to the extent
required by law.

              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 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 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 Security
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


<PAGE>   76
                                       67


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 Securities 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 Securities because of the reinstatement of its obligations, the Company
shall be subrogated to the rights of the Holders of such Securities to receive
such payment from the money or U.S. Government Obligations held by the Trustee
or Paying Agent.

              SECTION 8.07. Insiders. With respect to the determination of the
Persons constituting beneficial owners of Securities and whether any such Person
is an "insider" for purposes of Sections 8.02(B)(ii)(y) and 8.03(iv)(E), the
Trustee shall be entitled to receive, and shall be fully protected in relying
upon, an Officers' Certificate.

                                  ARTICLE NINE
                       AMENDMENTS, SUPPLEMENTS AND WAIVERS


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

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

              (b)    to comply with Article Five;

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

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


<PAGE>   77
                                       68



              (e)    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; or

              (f)    to comply with any requirements of the Luxembourg Stock
       Exchange in order to list the Securities on such Exchange.

              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 Boards of Directors (as evidenced by a Board Resolution), and the Trustee
may amend this Indenture and the Securities with the written consent of the
Holders of a majority in principal amount of the Securities then outstanding,
and the Holders of a majority in principal amount of the Securities then
outstanding by written notice to the Trustee may waive future compliance by the
Company with any provision of this Indenture or the Securities.

              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 Security;

              (ii)   reduce the principal amount of, or premium, if any, or
       interest on, any Security, or adversely affect any right of repayment at
       the option of any Holder of any Security;

              (iii)  change the place or currency of payment of principal of, or
       premium, if any, or interest on, any Security;

              (iv)   impair the right to institute suit for the enforcement of
       any payment on or after the Stated Maturity (or, in the case of a
       redemption, on or after the Redemption Date) of any Security;

              (v)    reduce the above-stated percentage of outstanding
       Securities the consent of whose Holders is required for any supplemental
       indenture, for any waiver of compliance with certain provisions of this
       Indenture or for waiver of certain Defaults and their consequences
       provided for in this Indenture;

              (vi)   waive a default in the payment of principal of, premium, if
       any, or interest on the Securities; or

              (vii)  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 Security affected thereby.


<PAGE>   78
                                       69


              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 Security or portion of a Security
that evidences the same debt as the Security of the consenting Holder, even if
notation of the consent is not made on any Security. However, any such Holder or
subsequent Holder may revoke the consent as to its Security or portion of its
Security. 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 Securities.

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

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


<PAGE>   79
                                       70



              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, duties or immunities of the Trustee under this Indenture or otherwise.
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
                                  MISCELLANEOUS


              SECTION 10.01. 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 10.02. 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:

                     Alferez Pareja 256
                     1107 Buenos Aires Argentina
                     Attention:  Chief Executive Officer

              if to the Trustee:

                     The Bank of New York
                     101 Barclay Street
                     Floor 21 West
                     New York, New York 10286
                     Attention:  Corporate Trust Administration

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


<PAGE>   80
                                       71



              Any notice or communication mailed to a Holder shall be mailed to
him at his address as it appears on the Security 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. In addition, for so long as the
Securities are listed on the Luxembourg Stock Exchange, all notices and
communications to be delivered to the Holders shall be published in a leading
newspaper of general circulation in Luxembourg, which is expected to be the
Luxembourger Wort.

              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 10.02, it is duly given,
whether or not the addressee receives it. If, by reason of the suspension of
publication or general circulation of any newspaper or otherwise, it shall be
impracticable to publish notice to the Holders in the manner described herein,
then any manner of giving such notice as shall be satisfactory to the Trustee
shall be deemed a sufficient giving of such notice.

              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 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 10.03. 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 10.04. 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;


<PAGE>   81
                                       72


              (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 10.05. 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.

              SECTION 10.06. Payment Date Other Than a Business Day. If an
Interest Payment Date, Redemption Date, Payment Date, Stated Maturity or date of
maturity of any Security shall not be a Business Day, then payment of principal
of, premium, if any, or interest on such Security, 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, Payment Date,
Redemption Date, or at the Stated Maturity or date of maturity of such Security;
provided that no interest shall accrue for the period from and after such
Interest Payment Date, Payment Date, Redemption Date, Stated Maturity or date of
maturity, as the case may be.

              SECTION 10.07. Governing Law. This Indenture and the Securities
shall be governed by the laws of the State of New York. The Company hereby
agrees that service of process upon the Company's registered agent in the State
of Delaware, currently located at Corporation Trust Center, 1209 Orange Street,
Wilmington, DE, 19801 and written notice of such service to the Company (mailed
or delivered to the Chief Executive Officer of the Company at its principal
office at Alferez Pareja 256, 1107 Buenos Aires, Republic of Argentina), shall
be deemed to be in every respect effective service of process upon the Company,
in any suit, action or proceeding arising out of or relating to this Indenture
or the Securities.

              Each of the Company, the Trustee and the Holders agrees to submit
to the non-exclusive jurisdiction of the federal or state courts of the State of
New York sitting in the City of New York, Borough of Manhattan, in any such
action or proceeding. The Company hereby waives to the fullest extent permitted
by law any defense to the institution or continuance of any such suit, action or
proceeding based upon lack of proper venue, inconvenient forum or similar
grounds.

              SECTION 10.08. No Adverse Interpretation of Other Agreements. This
Indenture may not be used to interpret another indenture, loan or debt agreement
of the Company


<PAGE>   82
                                       73


or any Subsidiary of the Company. Any such indenture, loan or debt agreement may
not be used to interpret this Indenture.

              SECTION 10.09. No Recourse Against Others. No recourse for the
payment of the principal of, premium, if any, or interest on any of the
Securities, 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 Securities, 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
equity holder, 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 Securities.

              SECTION 10.10. Successors. All agreements of the Company in this
Indenture and the Securities shall bind their respective successors. All
agreements of the Trustee in this Indenture shall bind its successors.

              SECTION 10.11. 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 10.12. Currency Indemnity. U.S. dollars are the sole
currency of account and payment for all sums payable by the Company under or in
connection with the Securities, including damages. Any amount received or
recovered in a currency other than U.S. dollars (whether as a result of, or of
the enforcement of, a judgment or order of a court of any jurisdiction, in the
winding-up or dissolution of the Company or otherwise) by any Holder of a
Security in respect of any sum expressed to be due to it from the Company shall
only constitute a discharge to the Company to the extent of the U.S. dollar
amount which the recipient is able to purchase with the amount so received or
recovered in that other currency on the date of that receipt or recovery (or, if
it is not practicable to make that purchase on that date, on the first date on
which it is practicable to do so). If that U.S. dollar amount is less than the
U.S. dollar amount expressed to be due to the recipient under any Security, the
Company shall indemnify the recipient against any loss sustained by it as a
result. In any event, the Company shall indemnify the recipient against the cost
of making any such purchase. For the purposes of this paragraph, it will be
sufficient for the Holder of a Security to certify in a satisfactory manner
(indicating the sources of information used) that it would have suffered a loss
had an actual purchase of U.S. dollars been made with the amount so received in
that other currency on the date of receipt or recovery (or, if a purchase of
U.S. dollars on such date had not been practicable, on the first date on which
it would have been practicable, it being required that the need for a change of
date be certified in the manner mentioned above). These indemnities constitute a
separate and independent obligation from the Company's other obligations, shall
give rise to a separate and independent cause of action, shall apply
irrespective of any indulgence granted by any Holder of


<PAGE>   83
                                       74


a Security and shall continue in full force and effect despite any other
judgment, order, claim or proof for a liquidated amount in respect of any sum
due under any Security.

              SECTION 10.13. Currency Translations. For purposes of determining
compliance with this Indenture, the U.S. dollar equivalent of any amounts
denominated in a foreign currency shall be calculated using the noon dollar
buying rate in New York City for wire transfers of such currency as published by
the Federal Reserve Bank of New York on the date of such foreign currency amount
is received, incurred or paid. For other financial reporting purposes, currency
translations will be performed in accordance with GAAP.

              SECTION 10.14. 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.


<PAGE>   84





                                   SIGNATURES

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



                            IMPSAT FIBER NETWORKS, INC.

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



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



                                THE BANK OF NEW YORK



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



                                BANQUE INTERNATIONALE A
                                   LUXEMBOURG S.A.


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


<PAGE>   85





                                                                       EXHIBIT A

                                 [FACE OF NOTE]

                           IMPSAT FIBER NETWORKS, INC.

                          13 3/4% Senior Note Due 2005

                                                                 [CUSIP        ]
                                                                 [ISIN         ]


No.                                                                   $_________

              IMPSAT FIBER NETWORKS, 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 15,
2005.

              Interest Payment Dates: February 15 and August 15, commencing
August 15, 2000.

              Regular Record Dates: February 1 and August 1.

              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>   86
                                       A-2





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

                                IMPSAT FIBER NETWORKS, INC.

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



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


<PAGE>   87
                                       A-3




                (Form of Trustee's Certificate of Authentication)

              This is one of the 13 3/4% Senior Notes due 2005 described in the
within-mentioned Indenture.


Date:  February 16, 2000                    THE BANK OF NEW YORK,
                                             as Trustee



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


<PAGE>   88
                                       A-4



                             [REVERSE SIDE OF NOTE]

                           IMPSAT FIBER NETWORKS, INC.

                          13 3/4% Senior Note due 2005

1. Principal and Interest.

              The Company will pay the principal of this Note on February 15,
2005.

              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 February 15 or August 15 immediately
preceding the Interest Payment Date) on each Interest Payment Date, commencing
August 15, 2000.

              If an exchange offer registered under the Securities Act is not
consummated, and 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 August 16, 2000 in accordance with the terms of the Registration
Rights Agreement dated February 16, 2000 between the Company and Morgan Stanley
& Co. Incorporated, the rate of interest will increase by 0.5% per annum to 14
1/4% per annum, payable in cash semiannually, in arrears, on each Interest
Payment Date, commencing February 15, 2001. Notwithstanding the preceding two
sentences, the failure to cause such exchange offer to be consummated or such
shelf registration statement to be declared effective shall be deemed not to be
a default or breach of a covenant for purposes of Section 6.01(c) of the
Indenture. Upon consummation of the exchange offer or the effectiveness of the
shelf registration statement, as the case may be, the rate of interest will
decrease to the original rate of interest as set forth on the face of this Note.
The Holder of this Note is entitled to the benefits of such Registration Rights
Agreement. To the extent there is a conflict between this Note and such
Registration Rights Agreement, such Registration Rights Agreement shall control
to the extent permitted by applicable law.

              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 16,
2000; 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 (to the extent lawful) interest on overdue installments of interest
at the rate per annum borne by the Notes.


<PAGE>   89
                                       A-5



2. Method of Payment.

              The Company will pay principal as provided above and interest
(except defaulted interest) on the principal amount of the Notes as provided
above on each February 15 and August 15 to the persons who are Holders (as
reflected in the Security Register at the close of business on the February 1
and August 1 immediately preceding the Interest Payment Date), in each case,
even if the Note is canceled on registration of transfer or registration of
exchange after such record date; provided that, with respect to the payment of
principal, the Company will not make payment to the Holder unless this Note is
surrendered to a Paying Agent.

              The Company will pay principal, premium, if any, and as provided
above, interest in money of the United States of America that at the time of
payment is legal tender for payment of public and private debts. However, the
Company may pay interest by its check payable in such money mailed to a Holder's
registered address (as reflected in the Security 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
February 16, 2000 (the "Indenture"), between the Company, as issuer, and The
Bank 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 unsubordinated indebtedness of the
Company, will rank pari passu in right of payment with all existing and future
unsecured, unsubordinated indebtedness of the Company and will be senior in
right of payment to all subordinated indebtedness of the Company. The Company
may, subject to Article Five of the Indenture and applicable law, issue
additional Notes under the Indenture.

5. Redemption.


<PAGE>   90
                                       A-6


              The Notes are redeemable, in whole or in part, at any time at the
Company's option at a redemption price (the "Make-Whole Price") equal to the
greater of (i) 100% of the principal amount thereof or (ii) as determined by an
Independent Investment Banker, the sum of the present values of the Remaining
Scheduled Payments discounted to the Redemption Date on a semiannual basis
(assuming a 360-day year consisting of twelve 30-day months) at the Adjusted
Treasury Rate, plus, in each case, accrued and unpaid interest (including
Additional Interest, as provided for in the Registration Rights Agreement), if
any, to the date of redemption.

              "Adjusted Treasury Rate" means with respect to any Redemption
Date, the rate per annum equal to the semiannual equivalent yield to maturity of
the Comparable Treasury Issue, assuming a price for the Comparable Treasury
Issue (expressed as a percentage of its principal amount) equal to the
Comparable Treasury Price for such Redemption Date, plus 0.50%.

              "Comparable Treasury Issue" means the United States Treasury
Security selected by an Independent Investment Banker as having a maturity
comparable to the remaining term of the Notes that would be utilized, at the
time of selection and in accordance with customary financial practice, in
pricing new issues of corporate debt securities of comparable maturity to the
remaining term of the Notes.

              "Comparable Treasury Price" means, the respect to any Redemption
Date, (i) the average of the bid and asked prices for the Comparable Treasury
Issue (expressed in each case as a percentage of its principal amount) on the
third Business Day preceding such Redemption Date, as set forth in the daily
statistical release (or any successor release) published by the Federal Reserve
Bank of New York and designated "Composite 3:30 p.m. Quotations for U.S.
Government Securities" or (ii) if such release (or any successor release) is not
published or does not contain such prices on such Business Day, (A) the
Reference Treasury Dealer Quotations for such Redemption Date, after excluding
the highest and lowest of such Reference Treasury Dealer Quotations, or (B) if
the Trustee obtains fewer than three such Reference Treasury Dealer Quotations,
the average of all such Quotations.

              "Independent Investment Banker" means any Reference Treasury
Dealer appointed by the Trustee after consultation with the Company.

              "Reference Treasury Dealer" means each of Morgan Stanley & Co.
Incorporated, Chase Securities Inc., First Union Capital Markets, a division of
Wheat First Securities, Inc., NationsBanc Montgomery Securities LLC and TD
Securities (USA) Inc. and their respective successors; provided, however, that
if any of the foregoing shall case to be a primary U.S. Government securities
dealer in New York City (a "Primary Treasury Dealer"), the Company shall
substitute another Primary Treasury Dealer.

              "Reference Treasury Dealer Quotations" means, with respect to each
Reference Treasury Dealer and any Redemption Date, the average as determined by
the Trustee, of the bid and asked prices of the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) quoted in
writing to the Trustee by such Reference Treasury Dealer at 5:00 p.m. on the
third Business Day preceding such Redemption Date.



<PAGE>   91
                                       A-7



              "Remaining Scheduled Payments" means, with respect to each Note to
be redeemed, the remaining scheduled payments of the principal thereof and
interest thereon that would be due after the related Redemption Date but for
such redemption; provided, however, that, if such Redemption Date is not an
Interest Payment Date with respect to such Note, the amount of the next
succeeding scheduled interest payment thereon will be reduced by the amount of
interest accrued and unpaid thereon to such Redemption Date.

              In addition, at any time prior to February 16, 2003, the Company
may redeem up to 35% of the principal amount of the Notes originally issued with
the Net Cash Proceeds (other than proceeds from the exercise of the
over-allotment option by the underwriters in connection with the Company's
initial public offering) of one or more public or private issuances of Capital
Stock (other than Disqualified Stock) at any time or from time to time in part,
at a Redemption Price of 113.750% of the principal amount thereof on the
Redemption Date, together with accrued and unpaid interest, if any, thereon;
provided that (i) at least 65% of the principal amount of the Notes remain
outstanding after each such redemption and (ii) notice of such redemption is
mailed within 60 days of such issuance.

6. Notice of Redemption.

              Notice of 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 such Holder's last address as it appears in the Security Register. Notes in
original denominations larger than $1,000 may be redeemed in part; provided that
Notes will only be issued in denominations of $1,000 principal amount or
integral multiples thereof. 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.

7. Repurchase upon Change in Control.

              Upon the occurrence of any Change of Control, each Holder shall
have the right to require the repurchase of its Notes by the Company in cash
pursuant to the offer described in the Indenture at a purchase price equal to
101% of the principal amount thereof plus accrued and unpaid interest, if any,
to the date of purchase (the "Change of Control Payment").

              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 Security Register. Notes in original denominations larger than
$1,000 may be sold to the Company in part; provided that Notes will only be
issued in denominations of $1,000 principal amount or integral multiples
thereof. On and after the Change of Control Payment Date, interest ceases to
accrue on Notes or portions of Notes surrendered for purchase by the Company,
unless the Company defaults in the payment of the Change of Control Payment.

8. Denominations; Transfer; Exchange.


<PAGE>   92
                                      A-8


              The Notes are in registered form without coupons in denominations
of $1,000 of principal amount and integral multiples 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.

9. Persons Deemed Owners.

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

10. 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. After that, Holders entitled to the money
must look to the Company for payment, unless an applicable law designates
another Person, and all liability of the Trustee and such Paying Agent with
respect to such money shall cease.

11. 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 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.

12. 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.

13. Restrictive Covenants.

              The Indenture imposes certain limitations on the ability of the
Company and its Restricted Subsidiaries, among other things, to incur additional
indebtedness; create liens; engage in sale-leaseback transactions; pay dividends
or make distributions in respect of their capital stock; make investments or
make certain other restricted payments; sell assets; issue or


<PAGE>   93
                                      A-9


sell stock of Restricted Subsidiaries; enter into transactions with stockholders
or affiliates; or, with respect to the Company, consolidate, merge or sell all
or substantially all of their assets. Within 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.

14. Successor Persons.

              Generally, 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.

15. Defaults and Remedies.

              Any of the following events shall constitute an Event of Default
under the Indenture:

              (a)    default in the payment of principal of (or premium, if any,
       on) any Note when the same becomes due and payable at maturity, upon
       acceleration, redemption or otherwise;

              (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;

              (c)    the Company defaults in the performance of or breaches any
       other covenant or agreement of the Company in the Indenture or under the
       Notes 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;

              (d)    there occurs with respect to any issue or issues of
       Indebtedness of the Company or any Significant Subsidiary having an
       outstanding principal amount of $5 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;

              (e)    any final judgment or order (not covered by insurance) for
       the payment of money in excess of $5 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 either (A) an enforcement proceeding shall
       have been commenced by a creditor upon such judgment or order or (B)
       there shall be any period of 30 consecutive days following entry of the
       final judgment or order that causes the


<PAGE>   94
                                      A-10


       aggregate amount for all such final judgments or orders outstanding and
       not paid or discharged against all such Persons to exceed $5 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;

              (f)    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 30 consecutive days; or

              (g)    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 (other than an Event of Default specified in clause (f)
or (g) above that occurs with respect to the Company) occurs and is continuing
under the 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 principal,
premium, if any, and accrued interest on the Notes to be immediately due and
payable. If a bankruptcy or insolvency default with respect to the Company
occurs and is continuing, the principal of, premium, if any, and accrued
interest on the Notes automatically becomes due and payable without any
declaration or other act on the part of the Trustee or any Holder. 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.

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.


<PAGE>   95
                                      A-11



              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. Such 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).

              The Company will furnish to any Holder upon written request and
without charge a copy of the Indenture. Requests may be made to IMPSAT Fiber
Networks, Inc., Alferez Pareja 256, 1107 Buenos Aires, Republic of Argentina
Attention: Chief Executive Officer.


<PAGE>   96
                                      A-12





                            [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 SECURITIES OTHER THAN EXCHANGE SECURITIES, OFFSHORE GLOBAL
                  SECURITIES AND OFFSHORE PHYSICAL SECURITIES]

       In connection with any transfer of this Note occurring prior to the date
which is the earlier of (i) the date of an effective Registration Statement 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>   97
                                      A-13



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>   98
                                      A-14



                       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):

$                 .
  ----------------

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


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


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

<PAGE>   99





                                                                       EXHIBIT B

                               Form of Certificate


                                                                ------- --, ----


THE BANK OF NEW YORK
101 Barclay Street
Floor 21 West
New York, New York 10286



Attention:  Corporate Trust Administration

                     Re: IMPSAT FIBER NETWORKS, INC. (the "Company")
                                    13 3/4% Senior Notes
                                 due 2005 (the "Securities")

Ladies and Gentlemen:


              This letter relates to U.S. $______ principal amount of Securities
represented by a Note (the "Legended Note") which bears a legend outlining
restrictions upon transfer of such Legended Note. Pursuant to Section 2.02 of
the Indenture (the "Indenture") dated as of February 16, 2000 relating to the
Securities, we hereby certify that we are (or we will hold such Securities on
behalf of) a person outside the United States to whom the Securities 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 of Securities, 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>   100



                                                                       EXHIBIT C

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


                                                                 ------ --, ----



THE BANK OF NEW YORK
101 Barclay Street
Floor 21 West
New York, New York 10286


Attention:  Corporate Trust Administration

                      Re: IMPSAT FIBER NETWORKS, INC. (the "Company")
                                    13 3/4% Senior Notes
                                 due 2005 (the "Securities")

Ladies and Gentlemen:

              In connection with our proposed sale of U.S.$______ aggregate
principal amount of the Securities, 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 Securities 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 Securities Act of 1933.

              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


<PAGE>   101
                                      C-2


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>   102





                                                                       EXHIBIT D

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

                                                                 ------ --, ----



THE BANK OF NEW YORK
101 Barclay Street
Floor 21 West
New York, New York 10286



Attention:  Corporate Trust Administration

                     Re:    IMPSAT FIBER NETWORKS, INC. (the "Company")
                                       13 3/4% Senior Notes
                                    due 2005 (the "Securities")

Ladies and Gentlemen:

              In connection with our proposed purchase of $___________ aggregate
principal amount of the Securities, we confirm that:

              1.     We understand that any subsequent transfer of the
       Securities is subject to certain restrictions and conditions set forth in
       the Indenture dated as of February 16, 2000 relating to the Securities
       (the "Indenture") and the undersigned agrees to be bound by, and not to
       resell, pledge or otherwise transfer the Securities except in compliance
       with, such restrictions and conditions and the Securities Act of 1933, as
       amended (the "Securities Act").


<PAGE>   103



              2.     We understand that the offer and sale of the Securities
       have not been registered under the Securities Act, and that the
       Securities 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 Securities, 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 substantially in
       the form of this letter, and, if such transfer is in respect of an
       aggregate principal amount 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 accordance with Rule 904
       of Regulation S under the Securities Act, (E) pursuant to the provisions
       of Rule 144 under the Securities Act (if available) 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 Securities from us a
       notice advising such purchaser that resales of the Securities are
       restricted as stated herein.

              3.     We understand that, on any proposed resale of any
       Securities, 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
       Securities 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 Securities, 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 Securities 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]


<PAGE>   104


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