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                                360networks inc.








                                U.S. $600,000,000

                            13% SENIOR NOTES DUE 2008


                                    INDENTURE

                           Dated as of April 26, 2000












                                 HSBC Bank USA,

                                     Trustee



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<PAGE>

                                TABLE OF CONTENTS


                                                                            Page

                                    ARTICLE 1
                   DEFINITIONS AND INCORPORATION BY REFERENCE

Section 1.01.     Definitions.................................................1
Section 1.02.     Other Definitions..........................................23
Section 1.03.     Incorporation by Reference of Trust Indenture Act..........24
Section 1.04.     Rules of Construction......................................24

                                    ARTICLE 2
                                    THE NOTES

Section 2.01.     Form and Dating............................................25
Section 2.02.     Execution and Authentication...............................26
Section 2.03.     Registrar and Paying Agent.................................26
Section 2.04.     Paying Agent to Hold Money in Trust........................27
Section 2.05.     Holder Lists...............................................27
Section 2.06.     Transfer and Exchange......................................27
Section 2.07.     Replacement Notes..........................................38
Section 2.08.     Outstanding Notes..........................................38
Section 2.09.     Treasury Notes.............................................38
Section 2.10.     Temporary Notes............................................38
Section 2.11.     Cancellation...............................................39
Section 2.12.     Defaulted Interest.........................................39

                                    ARTICLE 3
                            REDEMPTION AND PREPAYMENT

Section 3.01.     Notices to Trustee.........................................39
Section 3.02.     Selection of Notes to Be Redeemed..........................39
Section 3.03.     Notice of Redemption.......................................40
Section 3.04.     Effect of Notice of Redemption.............................40
Section 3.05.     Deposit of Redemption Price................................40
Section 3.06.     Notes Redeemed in Part.....................................41
Section 3.07.     Optional Redemption........................................41
Section 3.08.     Mandatory Redemption.......................................41
Section 3.09.     Offer to Purchase by Application of Excess Proceeds........41

                                    ARTICLE 4
                                    COVENANTS

Section 4.01.     Payment of Notes...........................................43
Section 4.02.     Maintenance of Office or Agency............................43
Section 4.03.     Reports....................................................44
Section 4.04.     Compliance Certificate.....................................44


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Section 4.05.     Taxes; Payment of Additional Amounts.......................45
Section 4.06.     Stay, Extension and Usury Laws.............................46
Section 4.07.     Restricted Payments........................................46
Section 4.08.     Dividend and Other Payment Restrictions Affecting
                    Subsidiaries.............................................49
Section 4.09.     Incurrence of Indebtedness and Issuance of Preferred
                    Stock....................................................51
Section 4.10.     Limitation on Asset Sales..................................54
Section 4.11.     Transactions with Affiliates...............................55
Section 4.12.     Liens......................................................56
Section 4.13.     Corporate Existence........................................56
Section 4.14.     Repurchase at the Option of Holders upon a Change of
                    Control..................................................56
Section 4.15.     No Senior Subordinated Debt................................58
Section 4.16.     Issuances of Guarantees by Restricted Subsidiaries.........58
Section 4.17.     Designation of Restricted and Unrestricted Subsidiaries....59
Section 4.18.     Payments for Consent.......................................59
Section 4.19.     Business Activities........................................59

                                    ARTICLE 5
                                   SUCCESSORS

Section 5.01.     Amalgamation, Merger, Consolidation, or Sale of Assets.....59
Section 5.02.     Successor Corporation Substituted..........................60

                                    ARTICLE 6
                              DEFAULTS AND REMEDIES

Section 6.01.     Events of Default..........................................61
Section 6.02.     Acceleration...............................................62
Section 6.03.     Other Remedies.............................................63
Section 6.04.     Waiver of Past Defaults....................................63
Section 6.05.     Control by Majority........................................63
Section 6.06.     Limitation on Suits........................................63
Section 6.07.     Rights of Holders of Notes to Receive Payment..............64
Section 6.08.     Collection Suit by Trustee.................................64
Section 6.09.     Trustee May File Proofs of Claim...........................64
Section 6.10.     Priorities.................................................64
Section 6.11.     Undertaking for Costs......................................65
Section 6.12.     Indemnification for Judgment Currency Fluctuations.........65

                                    ARTICLE 7
                                     TRUSTEE

Section 7.01.     Duties of Trustee..........................................65
Section 7.02.     Rights of Trustee..........................................66
Section 7.03.     Individual Rights of Trustee...............................67
Section 7.04.     Trustee's Disclaimer.......................................67
Section 7.05.     Notice of Defaults.........................................67
Section 7.06.     Reports by Trustee to Holders of the Notes.................68
Section 7.07.     Compensation and Indemnity.................................68


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Section 7.08.     Replacement of Trustee.....................................69
Section 7.09.     Successor Trustee by Merger, etc...........................69
Section 7.10.     Eligibility; Disqualification..............................70
Section 7.11.     Preferential Collection of Claims Against Company..........70

                                    ARTICLE 8
                    LEGAL DEFEASANCE AND COVENANT DEFEASANCE

Section 8.01.     Option to Effect Legal Defeasance or Covenant Defeasance...70
Section 8.02.     Legal Defeasance and Discharge.............................70
Section 8.03.     Covenant Defeasance........................................71
Section 8.04.     Conditions to Legal or Covenant Defeasance.................71
Section 8.05.     Deposited Money and Government Securities to be Held in
                    Trust; Other Miscellaneous Provisions....................72
Section 8.06.     Repayment to Company.......................................73
Section 8.07.     Reinstatement..............................................73

                                    ARTICLE 9
                        AMENDMENT, SUPPLEMENT AND WAIVER

Section 9.01.     Without Consent of Holders of Notes........................73
Section 9.02.     With Consent of Holders of Notes...........................74
Section 9.03.     Compliance with Trust Indenture Act........................75
Section 9.04.     Revocation and Effect of Consents..........................75
Section 9.05.     Notation on or Exchange of Notes...........................76
Section 9.06.     Trustee to Sign Amendments, etc............................76

                                   ARTICLE 9A
                             SATISFACTION AND WAIVER

Section 9.01A     Satisfaction and Discharge of Indenture....................76
Section 9.02A     Application of Trust Money.................................77

                                   ARTICLE 10
                                  MISCELLANEOUS

Section 10.01.    Trust Indenture Act Controls...............................77
Section 10.02.    Notices....................................................77
Section 10.03.    Communication by Holders of Notes with Other Holders
                    of Notes.................................................78
Section 10.04.    Certificate and Opinion as to Conditions Precedent.........78
Section 10.05.    Statements Required in Certificate or Opinion..............78
Section 10.06.    Rules by Trustee and Agents................................79
Section 10.07.    No Personal Liability of Directors, Officers, Employees
                    and Stockholders.........................................79
Section 10.08.    Governing Law..............................................79
Section 10.09.    Jurisdiction...............................................79
Section 10.10.    No Adverse Interpretation of Other Agreements..............80
Section 10.11.    Successors.................................................80
Section 10.12.    Severability...............................................80


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Section 10.13.    Counterpart Originals......................................80
Section 10.14.    Table of Contents, Headings, etc...........................80





                                    EXHIBITS

Exhibit A         FORM OF NOTE
Exhibit B         FORM OF CERTIFICATE OF TRANSFER
Exhibit C         FORM OF CERTIFICATE OF EXCHANGE
Exhibit D         FORM OF CERTIFICATE OF ACQUIRING INSTITUTIONAL
                  ACCREDITED INVESTOR





                                      -iv-
<PAGE>



     INDENTURE dated as of April 26, 2000, between 360networks inc., a company
continued under the laws of the Province of Nova Scotia, Canada (the "Company"),
and HSBC Bank USA, as trustee (the "Trustee").

     The Company and the Trustee agree as follows for the benefit of each other
and for the equal and ratable benefit of the Holders of the 13% Senior Notes due
2008 (the "Notes"):

                                    ARTICLE 1
                   DEFINITIONS AND INCORPORATION BY REFERENCE

Section 1.01.     Definitions.

     "144A Global Note" means a global note substantially in the form of Exhibit
A hereto bearing the Global Note Legend and the Private Placement Legend and
deposited with or on behalf of, and registered in the name of, the Depositary or
its nominee that will be issued in a denomination equal to the outstanding
principal amount of the Notes sold in reliance on Rule 144A.

     "1998 Notes" means the Company's 12.5% Senior Notes due 2005.

     "1999 Notes" means the Company's 12% Senior Notes due 2009.

     "Acquired Debt" means, with respect to any specified Person:

     (1)  Indebtedness of any other Person existing at the time such other
          Person is merged with or into or became a Subsidiary of such specified
          Person; provided that such Indebtedness was not incurred in connection
          with, or in contemplation of, such other Person merging with or into,
          or becoming a Subsidiary of, such specified Person; and

     (2)  Indebtedness secured by a Lien encumbering any asset acquired by such
          specified Person.

     "Additional Interest" has the meaning set forth in Section 5 of the
Registration Rights Agreement.

     "Adjusted Consolidated Cash Flow" means Consolidated Cash Flow minus all
non-cash items increasing Consolidated Net Income for the applicable period to
the extent not previously deducted in computing Consolidated Cash Flow, whether
or not such non-cash items were accrued or incurred in the ordinary course of
business or otherwise.

     "Adjusted Fiber Value" means, at any time after certain Affiliates of
Ledcor Inc. have contributed dark fiber strands to the Company pursuant to the
Undertaking Agreements, an amount equal to $72.5 million less one-twelfth (1/12)
of such amount for each of such dark fiber strands which has been sold, leased,
contributed or with respect to which an IRU has been granted to any Person.

     "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person. For purposes of this definition, "control,"
as used with respect to any Person, shall mean the possession, directly or
indirectly, of the power to direct or cause the direction of the management or
policies of such Person, whether through the ownership of voting securities, by
agreement or otherwise; provided that beneficial ownership of 10% or more of the
Voting Stock of a Person shall be deemed to be control. For purposes of this
definition, the terms "controlling," "controlled by" and "under common control
with" shall have correlative meanings.


<PAGE>
                                      -2-


     "Agent" means any Registrar, Paying Agent or co-registrar.

     "Applicable Procedures" means, with respect to any transfer or exchange of
or for beneficial interests in any Global Note, the rules and procedures of the
Depositary, Euroclear and Clearstream that apply to such transfer or exchange.

     "Asset Sale" means:

     (1)  the sale, lease, conveyance or other disposition of any assets or
          rights other than any sale, lease, transfer, conveyance, or other
          disposition of telecommunications capacity, transmission rights, or
          other telecommunications services provided over the Company's network
          in the ordinary course of business; provided that the sale, conveyance
          or other disposition of all or substantially all of the assets of the
          Company and its Restricted Subsidiaries taken as a whole will be
          governed by the provisions of Section 4.14 and/or Section 5.01 and not
          by the provisions of Section 4.10; and

     (2)  the issuance of Equity Interests by any of the Company's Restricted
          Subsidiaries or the sale of Equity Interests in any of its
          Subsidiaries,

     Notwithstanding the preceding, the following items shall be deemed not to
be Asset Sales:

     (1)  any single transaction or series of related transactions that: (a)
          involves assets having a fair market value of less than $1.0 million;
          or (b) results in net proceeds to the Company and its Restricted
          Subsidiaries of less than $1.0 million;

     (2)  a transfer of assets between or among the Company and its Restricted
          Subsidiaries or between Restricted Subsidiaries,

     (3)  Permitted Telecommunication Asset Dispositions;

     (4)  an issuance of Equity Interests by a Restricted Subsidiary to the
          Company or to a Wholly-Owned Restricted Subsidiary;

     (5)  a Permitted Investment or a Restricted Payment that is permitted by
          the provisions of Section 4.07; and

     (6)  sales of Equity Interests by the Company to minority shareholders of
          the Company; provided, such sales do not increase the ownership
          percentage of the minority shareholders of the Company in the Company.

     "Bankruptcy Law" means Title 11, U.S. Code, the Bankruptcy and Insolvency
Act (Canada) or the Companies' Creditors Arrangement Act (Canada) or any similar
federal, provincial, or state law of any jurisdiction relating to bankruptcy,
insolvency, winding up, liquidation, reorganization or relief of debtors.

     "Beneficial Owner" has the meaning assigned to such term in Rule 13d-3 and
Rule 13d-5 under the Exchange Act, except that in calculating the beneficial
ownership of any particular "person" (as such term is used in Section 13(d)(3)
of the Exchange Act), such "person" shall be deemed to have beneficial ownership
of all securities that such "person" has the right to acquire, whether such
right is currently exercisable or is exercisable only upon the occurrence of a
subsequent condition.


<PAGE>
                                      -3-


     "Board of Directors" means the Board of Directors of the Company, or any
authorized committee of the Board of Directors.

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

     "Broker-Dealer" has the meaning set forth in the Registration Rights
Agreement.

     "Business Day" means any day other than a Legal Holiday.

     "Canadian FOTS" means the 5,400 mile fiber optic network development across
Canada and the Northern United States constructed by Ledcor Inc. and its
Affiliates, as described in the Offering Memorandum.

     "Canadian Taxing Authority" means any federal, provincial, territorial or
other Canadian government or any authority or agency therein or thereof having
power to tax.

     "Capital Lease Obligation" means, at the time any determination thereof is
to be made, the amount of the liability in respect of a capital lease that would
at that time be required to be capitalized on a balance sheet in accordance with
GAAP.

     "Capital Stock" means:

     (1)  in the case of a corporation, corporate stock;

     (2)  in the case of an association or business entity, any and all shares,
          interests, participations, rights or other equivalents (however
          designated) of corporate stock;

     (3)  in the case of a partnership or limited liability company, partnership
          or membership interests (whether general or limited); and

     (4)  any other interest or participation that confers on a Person the right
          to receive a share of the profits and losses of, or distributions of
          assets of, the issuing Person.

     "Cash Equivalents" means any of the following:

     (1)  any investment in direct obligations of the United States of America
          or any agency thereof, of any European Union Member or any agency
          thereof or of Canada or any province or agency thereof of obligations
          guaranteed by the United States of America or any agency thereof, of
          any European Union Member or any agency thereof or of Canada or any
          province or agency thereof, in each case with a term of not more than
          one year (provided that any province of Canada must be rated at least
          "R-1" by the Dominion Bond Rating Service Limited);

     (2)  investments in time deposit accounts, term deposit accounts,
          certificates of deposit, money-market deposits, bankers acceptances
          and obligations maturing within one year of the date of acquisition
          thereof issued by a bank or trust company which is organized under the
          laws of the United States of America, any state thereof, any European
          Union Member, Canada or any province thereof, and which bank or trust
          company has, or the obligations of which bank or trust company is
          guaranteed by a bank or trust company which has, capital, surplus and
          undi-


<PAGE>
                                      -4-


          vided profits aggregating in excess of $150.0 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 by Dominion Bond Rating Service
          Limited or Canadian Bond Rating Service, Inc. or any money-market fund
          sponsored by a registered broker dealer or mutual fund distributor;

     (3)  repurchase obligations with a term of not more than 30 days for
          underlying securities of the types described in clause (1) above
          entered into with a bank meeting the qualifications described in
          clause (2) above;

     (4)  investments in commercial paper, maturing not more than 90 days after
          the date of acquisition, issued by a corporation (other than the
          Company or an Affiliate of the Company) organized and in existence
          under the laws of the United States of America, a European Union
          Member or Canada 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 or at least "R-1" by Dominion Bond Rating
          Service Limited or Canadian Bond Rating Service (in the case of a
          Canadian issuer);

     (5)  investments in securities with maturities of six months or less from
          the date of acquisition issued or fully guaranteed by any state,
          commonwealth, territory or province of the United States of America, a
          European Union Member or Canada, or by any political subdivision or
          taxing authority thereof, and rated at least "R-1" by the Dominion
          Bond Rating Service Limited (in the case of a Canadian issuer);

     (6)  investments in money market funds at least 95% of the assets of which
          constitute Cash Equivalents of the kinds described in clauses (1)
          through (5) of this definition; and

     (7)  all obligations of the United States of America, a European Union
          Member, Canada or any other sovereign nation which are authorized
          under the terms governing any Indebtedness of the Company from time to
          time outstanding to be deposited in connection with a legal
          defeasance, covenant defeasance or final discharge of such
          Indebtedness.

     "Change of Control" means the occurrence of any of the following:

     (1)  the sale, transfer, conveyance or other disposition (other than by way
          of merger or consolidation), in one or a series of related
          transactions, of all or substantially all of the assets of the Company
          and its Subsidiaries taken as a whole to any "person" (as such term is
          used in Section 13(d)(3) of the Exchange Act) other than a Permitted
          Holder;

     (2)  the adoption of a plan relating to the liquidation or dissolution of
          the Company;

     (3)  the consummation of any transaction (including, without limitation,
          any merger or consolidation) the result of which is that any "person"
          (as defined above), other than a Permitted Holder, becomes the
          Beneficial Owner, directly or indirectly, of more than 50% (the
          "Voting Threshhold") of the Voting Stock of the Company, measured by
          voting power rather than number of shares; provided that if, in the
          opinion of nationally recognized tax counsel to the Company, based on
          a change to the Income Tax Act (Canada) or regulations adopted
          thereunder, the published administrative practices of the Canada
          Customs and Revenue Agency or the publication


<PAGE>
                                      -5-


          of judicial decisions in each case, enacted, promulgated or published
          after the Issue Date, which change in law, regulation or publication
          of an administrative practice or judicial decision provides that in
          reference to a change of control which is an acceptable "triggering
          event" for purposes of subparagraph 212(1)(b)(vii) of the Income Tax
          Act (Canada), requiring the Company to initiate a Change of Control
          Offer, that control generally means a voting threshhold of 50% or less
          (the "Reduced Voting Threshhold"), then the Voting Threshhold shall be
          reduced on a prospective basis to such Reduced Voting Threshhold, but
          in no event shall the Reduced Voting Threshhold be less than 35%;

     (4)  the first day on which a majority of the members of the Board of
          Directors of the Company are not Continuing Directors;

     (5)  the Company consolidates with, or merges with or into, any Person, or
          any Person consolidates with, or merges with or into, the Company, in
          any such event pursuant to a transaction in which any of the
          outstanding Voting Stock of the Company is converted into or exchanged
          for cash, securities or other property, other than any such
          transaction where the Voting Stock of the Company outstanding
          immediately prior to such transaction is converted into or exchanged
          for Voting Stock (other than Disqualified Stock) of the surviving or
          transferee Person constituting a majority of the outstanding shares of
          such Voting Stock of such surviving or transferee Person immediately
          after giving effect to such issuance;

     (6)  any Person other than a Permitted Holder shall succeed in having a
          sufficient number of its nominees elected to the Board of Directors of
          the Company such that such nominees will constitute a majority of the
          Company's Board of Directors; or

     (7)  the Company or any of its Restricted Subsidiaries pursuant to or
          within the meaning of Bankruptcy Law:

               (i) commences a voluntary case,

               (ii) consents to the entry of an order for relief against it in
          an involuntary case,

               (iii) consents to the appointment of a custodian of it or for all
          or substantially all of its property,

               (iv) makes a general assignment for the benefit of its creditors,
          or

               (v) generally is not paying its debts as they become due; or

     (8)  a court of competent jurisdiction enters an order or decree under any
          Bankruptcy Law that:

               (i) is for relief against the Company or any of its Restricted
          Subsidiaries in an involuntary case;

               (ii) appoints a custodian of the Company or any of its Restricted
          Subsidiaries or for all or substantially all of the property of the
          Company or any of its Restricted Subsidiaries; or

               (iii) orders the liquidation of the Company or any of its
          Restricted Subsidiaries;


<PAGE>
                                      -6-


     and the order or decree remains unstayed and in effect for 60 consecutive
days.

     "Clearstream" means Clearstream Banking or any successor thereto.

     "Company" means 360networks inc., a company continued under the laws of the
Province of Nova Scotia, Canada, and any and all successors thereto.

     "Concurrent Equity Offering" means the initial public offering by the
Company of its Subordinate Voting Shares made pursuant to a registration
statement on Form F-1 (No. 333-95621) filed with the SEC on January 28, 2000, as
such registration statement is amended or supplemented from time to time.

     "Consolidated Capital Ratio" means, with respect to the Company as of any
date, the ratio of (i) the aggregate consolidated principal amount of
Indebtedness of the Company and its Restricted Subsidiaries then outstanding to
(ii) the Consolidated Net Worth of the Company and its Restricted Subsidiaries
as of such date, in each case as shown on the consolidated balance sheet of the
Company in accordance with GAAP.

     "Consolidated Cash Flow" means, with respect to any Person for any period,
the Consolidated Net Income of such Person for such period plus:

     (1)  provision for taxes based on income or profits of such Person and its
          Restricted Subsidiaries for such period, to the extent that such
          provision for taxes was deducted in computing such Consolidated Net
          Income; plus

     (2)  Fixed Charges of such Person and its Restricted Subsidiaries for such
          period, whether paid or accrued and whether or not capitalized
          (including, without limitation, amortization of debt issuance costs
          and original issue discount, non-cash interest payments, the interest
          component of any deferred payment obligations, the interest component
          of all payments associated with Capital Lease Obligations,
          commissions, discounts and other fees and charges incurred in respect
          of letter of credit or bankers' acceptance financings, and net
          payments, if any, pursuant to Hedging Obligations), to the extent that
          any such expense was deducted in computing such Consolidated Net
          Income; plus

     (3)  depreciation, amortization (including amortization of goodwill and
          other intangibles but excluding amortization of prepaid cash expenses
          that were paid in a prior period) and other non-cash expenses
          (excluding any such non-cash expense to the extent that it represents
          an accrual of or reserve for cash expenses in any future period or
          amortization of a prepaid cash expense that was paid in a prior
          period) of such Person and its Restricted Subsidiaries for such period
          to the extent that such depreciation, amortization and other non-cash
          expenses were deducted in computing such Consolidated Net Income;
          minus

     (4)  non-cash items increasing such Consolidated Net Income for such
          period, other than items that were accrued in the ordinary course of
          business, in each case, on a consolidated basis and determined in
          accordance with GAAP. Notwithstanding the preceding, the provision for
          taxes based on the income or profits of, and the depreciation and
          amortization and other non-cash charges of, a Restricted Subsidiary of
          the Company shall be added to Consolidated Net Income to compute
          Consolidated Cash Flow of the Company only to the extent that a
          corresponding amount would be permitted at the date of determination
          to be dividended to the Company by such Restricted Subsidiary without
          prior approval (that has not been obtained), pursuant to the


<PAGE>
                                      -7-


          terms of its charter and all agreements, instruments, judgments,
          decrees, orders, statutes, rules and governmental regulations
          applicable to that Subsidiary or its stockholders.

     "Consolidated Leverage Ratio" means, with respect to the Company, as of any
date, the ratio of (i) the aggregate amount of Indebtedness of the Company and
its Restricted Subsidiaries then outstanding (other than intercompany debt) to
(ii) the Consolidated Cash Flow of the Company and its Restricted Subsidiaries
on a consolidated basis for the most recently ended four fiscal quarters
immediately preceding the date of determination for which consolidated financial
statements of the Company are available (the "Reference Period").

     In addition to the foregoing, for purposes of this definition,
"Consolidated Cash Flow" shall be calculated on a pro forma basis after giving
effect to the issuance of the Notes and the Euro Notes and the incurrence of the
Indebtedness (and the application of the proceeds therefrom) giving rise to the
need to make such calculation and any incurrence (and the application of the
proceeds therefrom) or repayment of Indebtedness, other than the incurrence or
repayment of indebtedness for ordinary working capital purposes, at any time
subsequent to the beginning of the Reference Period and on or prior to the date
of determination, as if such occurrence (and the application of the proceeds
thereof), or the repayment, as the case may be, occurred on the first day of the
Reference Period.

     "Consolidated Net Income" means, with respect to any specified Person for
any period, the aggregate of the Net Income of such Person and its Restricted
Subsidiaries for such period, on a consolidated basis, determined in accordance
with GAAP; provided that:

     (1)  the Net Income (but not loss) of any Person that is not a Restricted
          Subsidiary or that is accounted for by the equity method of accounting
          shall be included only to the extent of the amount of dividends or
          distributions paid in cash to the specified Person or a Restricted
          Subsidiary thereof;

     (2)  the Net Income of any Restricted Subsidiary shall be excluded to the
          extent that the declaration or payment of dividends or similar
          distributions by that Restricted Subsidiary of that Net Income is not
          at the date of determination permitted without any prior governmental
          approval (that has not been obtained) or, directly or indirectly, by
          operation of the terms of its charter or any agreement, instrument,
          judgment, decree, order, statute, rule or governmental regulation
          applicable to that Restricted Subsidiary or its stockholders, it being
          understood that the Net Income of any such Restricted Subsidiary for
          such period shall be included in Consolidated Net Income up to the
          aggregate amount of cash that such Restricted Subsidiary could have
          paid pursuant to such dividends or similar distributions during such
          period to the Company or any of its Restricted Subsidiaries;

     (3)  the Net Income of any Person acquired in a pooling of interests
          transaction for any period prior to the date of such acquisition shall
          be excluded;

     (4)  the Net Income (but not loss) of any Unrestricted Subsidiary shall be
          excluded, whether or not distributed to the specified Person or one of
          its Subsidiaries, except for purposes of the provisions of Sections
          4.07 and 4.09 hereof, in which case the Net Income of any Unrestricted
          Subsidiary will be included to the extent it would otherwise be
          included under clause (1) of this definition above; and

     (5)  the cumulative effect of a change in accounting principles shall be
          excluded.


<PAGE>
                                      -8-


     "Consolidated Net Worth" means, with respect to the Company as of any date,
the sum of (i) the consolidated equity of the common stockholders of the Company
and its Restricted Subsidiaries that are Restricted Subsidiaries as of such date
plus (ii) the respective amounts reported on the Company's balance sheet as of
such date with respect to any series of Preferred Stock (other than Disqualified
Stock) that by its terms is not entitled to the payment of dividends unless such
dividends may be declared and paid only out of net earnings in respect of the
year of such declaration and payment, but only to the extent of any cash
received by the Company upon issuance of such Preferred Stock plus (iii) the
Adjusted Fiber Value, less (x) all write-ups (other than write-ups resulting
from foreign currency translations and write-ups of tangible assets of a going
concern business made within 12 months after the acquisition of such business)
subsequent to the Issue Date in the book value of any asset owned by the Company
or a Restricted Subsidiary of the Company, (y) all outstanding net Investments
as of such date in unconsolidated Restricted Subsidiaries and in Persons that
are not Restricted Subsidiaries, and (z) all unamortized debt discount and
expense and unamortized deferred charges as of such date, all of the foregoing
determined in accordance with GAAP.

     "Continuing Director" means, as of any date of determination, any member of
the Board of Directors of the Company who:

     (1)  was a member of such Board of Directors on the Issue Date; or

     (2)  was nominated for election or elected to such Board of Directors with
          the approval of a majority of the Continuing Directors who were
          members of such Board at the time of such nomination or election.

     "Corporate Trust Office of the Trustee" shall be at the address of the
Trustee specified in Section 10.02 hereof or such other address as to which the
Trustee may give notice to the Company.

     "Credit Facilities" means, with respect to the Company or any of its
Restricted Subsidiaries, one or more debt facilities or commercial paper
facilities, in each case with banks or other institutional lenders providing for
loans or letters of credit, in each case, as amended, restated, modified,
renewed, refunded, replaced or refinanced in whole or in part from time to time.

     "Custodian" means the Trustee, as custodian with respect to the Notes in
global form, or any successor entity thereto.

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

     "Definitive Note" means a certificated Note registered in the name of the
Holder thereof and issued in accordance with Section 2.06 hereof, substantially
in the form of Exhibit A hereto, except that such Note shall not bear the Global
Note Legend and shall not have the "Schedule of Exchanges of Interests in the
Global Note" attached thereto.

     "Depositary" means, with respect to the Global Notes, the Person specified
in Section 2.03 hereof as the Depositary with respect to the Notes, and any and
all successors thereto appointed as depositary hereunder and having become such
pursuant to the applicable provision of this Indenture.

     "Disqualified Stock" means any Capital Stock that, by its terms (or by the
terms of any security into which it is convertible, or for which it is
exchangeable, in each case at the option of the holder thereof), or upon the
happening of any event, matures or is mandatorily redeemable, pursuant to a
sinking fund obligation or oth-


<PAGE>
                                      -9-


erwise, or redeemable at the option of the holder thereof, in whole or in part,
on or prior to the date that is 91 days after the date on which the Notes
mature.

     Notwithstanding the preceding sentence, any Capital Stock that would
constitute Disqualified Stock solely because the holders thereof have the right
to require the Company to repurchase such Capital Stock upon the occurrence of a
change of control or an asset sale shall not constitute Disqualified Stock if
the terms of such Capital Stock provide that the Company may not repurchase or
redeem any such Capital Stock pursuant to such provisions unless such repurchase
or redemption complies with provisions of Section 4.07 hereof.

     "EEA Government Obligation" means direct non-callable obligations of, or
non-callable obligations guaranteed by, any European Union member for the
payment of which obligation or guarantee the full faith and credit of the
respective nation is pledged; provided that such nation has a credit rating at
least equal to that of the highest rated member nation of the European Economic
Area.

     "Eligible Investments" means cash or Cash Equivalents or such other
investment grade debt securities as the Board of Directors shall approve from
time to time; provided, however, that in no event shall any funds required to be
held as Eligible Investments be used, directly or indirectly, to repurchase any
Notes.

     "Equity Interests" means Capital Stock and all warrants, options or other
rights to acquire Capital Stock (but excluding any debt security that is
convertible into, or exchangeable for, Capital Stock).

     "Euro Exchange Notes" means the Euro Notes issued in an exchange offer
pursuant to Section 2.06(f) of the Euro Indenture.

     "Euro Indenture" means the indenture, dated as of April 28, 2000, between
the Company and HSBC Bank USA, as trustee, governing the Euro Notes.

     "Euro Notes" means the Company's euro-denominated 13% Senior Notes due
2008, issued pursuant to the Euro Indenture.

     "Euroclear" means Morgan Guaranty Trust Company of New York, Brussels
office, as operator of the Euroclear system.

     "European Economic Area" means the member nations of the European Economic
Area pursuant to the Oporto Agreement on the European Economic Area, dated May
2, 1992, as amended.

     "European Union Member" means any country that is or becomes a member of
the European Union or any successor organization thereto.

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

     "Exchange Notes" means the Notes issued in the Exchange Offer pursuant to
Section 2.06(f) hereof.

     "Exchange Offer" has the meaning set forth in the Registration Rights
Agreement.

     "Exchange Offer Registration Statement" has the meaning set forth in the
Registration Rights Agreement.


<PAGE>
                                      -10-


     "Existing Indebtedness" means Indebtedness of the Company or any of its
Restricted Subsidiaries outstanding on the Issue Date (other than the Credit
Facilities).

     "Fixed Charges" means, with respect to any Person for any period, the sum,
without duplication, of:

     (1)  the consolidated interest expense of such Person and its Restricted
          Subsidiaries for such period, whether paid or accrued, including,
          without limitation, amortization of debt issuance costs and original
          issue discount, non-cash interest payments, the interest component of
          any deferred payment obligations, the interest component of all
          payments associated with Capital Lease Obligations, commissions,
          discounts and other fees and charges incurred in respect of letter of
          credit or bankers' acceptance financings, and net payments, if any,
          pursuant to Hedging Obligations; plus

     (2)  the consolidated interest of such Person and its Restricted
          Subsidiaries that was capitalized during such period; plus

     (3)  any interest expense on Indebtedness of another Person that is
          Guaranteed by such Person or one of its Restricted Subsidiaries or
          secured by a Lien on assets of such Person or one of its Restricted
          Subsidiaries, whether or not such Guarantee or Lien is called upon;
          plus

     (4)  the product of (a) all dividend payments, whether or not in cash, on
          any series of preferred stock (including, without limitation,
          Disqualified Stock) of such Person or any of its Restricted
          Subsidiaries, other than dividend payments on Equity Interests payable
          solely in Equity Interests of the Company (other than Disqualified
          Stock) or to the Company or a Restricted Subsidiary of the Company,
          times (b) a fraction, the numerator of which is one and the
          denominator of which is one minus the then current combined federal,
          state and local statutory tax rate of such Person, expressed as a
          decimal, in each case, on a consolidated basis and in accordance with
          GAAP.

     "Foreign Subsidiary" means any Restricted Subsidiary of the Company which
(i) is not organized under the laws of (x) the United States or any state
thereof, (y) the District of Columbia or (z) Canada or any province thereof and
(ii) conducts substantially all of its business operations outside the United
States of America and Canada.

     "GAAP" means generally accepted accounting principles in the United States
as set forth in the opinions and pronouncements of the Accounting Principles
Board of the American Institute of Certified Public Accountants and statements
and pronouncements of the Financial Accounting Standards Board or in such other
statements by such other entity as have been approved by a significant segment
of the accounting profession, which are in effect from time to time.

     "Global Notes" means, individually and collectively, each of the Restricted
Global Notes and the Unrestricted Global Notes.

     "Global Note Legend" means the legend set forth in Section 2.06(g)(ii),
which is required to be placed on all Global Notes issued under this Indenture.

     "Government Securities" means direct obligations of, or obligations
guaranteed by, the United States of America, and the payment for which the
United States pledges its full faith and credit.


<PAGE>
                                      -11-


     "Guarantee" means a guarantee other than by endorsement of negotiable
instruments for collection in the ordinary course of business, direct or
indirect, in any manner including, without limitation, by way of a pledge of
assets or through letters of credit or reimbursement agreements in respect
thereof, of all or any part of any Indebtedness.

     "Hedging Obligations" means, with respect to any Person, the obligations of
such Person under:

     (1)  interest rate swap agreements, interest rate cap agreements and
          interest rate collar agreements; and

     (2)  other agreements or arrangements designed to protect such Person
          against fluctuations in interest rates.

     "Hibernia Subsidiaries" means Worldwide Telecom (USA) Inc., Worldwide
Telecom (Canada) Inc., WTI Telecom (UK) Limited, WTI Telecom (Ireland) Limited,
Worldwide Telecom (Barbados) Inc., Worldwide Telecom (Bermuda) Ltd., Worldwide
Telecom Limited, Worldwide Telecom (Denmark) ApS, WTI Telecom Distribution (UK)
Limited and Worldwide Telecom Distribution (USA) Inc.

     "Indebtedness" means, with respect to any specified Person, any
indebtedness of such Person, whether or not contingent, in respect of:

     (1)  borrowed money;

     (2)  evidenced by bonds, notes, debentures or similar instruments or
          letters of credit (or reimbursement agreements in respect thereof);

     (3)  banker's acceptances;

     (4)  representing Capital Lease Obligations;

     (5)  the balance deferred and unpaid of the purchase price of any property,
          except any such balance that constitutes an accrued expense or trade
          payable; or

     (6)  representing any Hedging Obligations, if and to the extent any of the
          preceding items (other than letters of credit and Hedging Obligations)
          would appear as a liability upon a balance sheet of the specified
          Person prepared in accordance with GAAP. In addition, the term
          "Indebtedness" includes all Indebtedness of others secured by a Lien
          on any asset of the specified Person (whether or not such Indebtedness
          is assumed by the specified Person, which shall be deemed the lesser
          of the full amount of such Indebtedness and the fair market value of
          the property or asset so secured) and, to the extent not otherwise
          included, the Guarantee by such Person of any indebtedness of any
          other Person.

     The amount of any Indebtedness outstanding as of any date shall be:

     (1)  the accreted value thereof, in the case of any Indebtedness issued
          with original issue discount; and

     (2)  the principal amount thereof, together with any interest thereon that
          is more than 30 days past due, in the case of any other Indebtedness.


<PAGE>
                                      -12-


     "Indenture" means this Indenture, as amended or supplemented from time to
time.

     "Indirect Participant" means a Person who holds a beneficial interest in a
Global Note through a Participant.

     "Institutional Accredited Investor" means an institution that is an
"accredited investor" as defined in Rule 501(a)(1), (2), (3) or (7) under the
Securities Act, who are not also QIBs.

     "Interest Expense" means, with respect to any Person for any period,
without duplication, the sum of (i) the consolidated interest expense of such
Person and its Restricted Subsidiaries for such period, whether paid or accrued
(including, without limitation, amortization of original issue discount,
non-cash interest payments, the interest component of any deferred payment
obligations, the interest component of all payments associated with Capital
Lease Obligations, commissions, discounts and other fees and charges incurred in
respect of letter of credit or bankers' acceptance financings), all calculated
after taking into account the effect of all Hedging Obligations, and (ii) the
consolidated interest expense of such Person and its Restricted Subsidiaries
that was capitalized during such period, and (iii) any interest expense on
Indebtedness of another Person that is guaranteed by such Person or one of its
Restricted Subsidiaries or secured by a Lien on assets of such Person or one of
its Restricted Subsidiaries (whether or not such Guarantee or Lien is called
upon) and (iv) the product of (a) all dividend payments on any series of
preferred stock of such Person or any of its Restricted Subsidiaries, times (b)
a fraction, the numerator of which is one and the denominator of which is one
minus the then current combined federal, state and local statutory tax rate of
such Person, expressed as a decimal, in each case, on a consolidated basis and
in accordance with GAAP.

     "Investments" means, with respect to any Person, all investments by such
Person in other Persons (including Affiliates) in the forms of direct or
indirect loans (including guarantees of Indebtedness or other obligations),
advances or capital contributions (excluding commission, travel and similar
advances to officers and employees made in the ordinary course of business),
purchases or other acquisitions for consideration of Indebtedness, Equity
Interests or other securities, together with all items that are or would be
classified as investments on a balance sheet prepared in accordance with GAAP.
If the Company or any Restricted Subsidiary of the Company sells or otherwise
disposes of any Equity Interests of any direct or indirect Restricted Subsidiary
of the Company such that, after giving effect to any such sale or disposition,
such Person is no longer a Restricted Subsidiary of the Company, the Company
shall be deemed to have made an Investment on the date of any such sale or
disposition equal to the fair market value of the Equity Interests of such
Restricted Subsidiary not sold or disposed of in an amount determined as
provided in the final paragraph of the provisions of Section 4.07.

     "IRU" means indefeasible rights of use, which is a long-term lease of
approximately 10 or 20 years with option periods thereafter to renew at lower
rates, at the option of the lessee.

     "Issue Date" means the first date on which any Notes were issued under this
Indenture.

     "Legal Holiday" means a Saturday, a Sunday or a day on which banking
institutions in the City of New York or at a place of payment are authorized by
law, regulation or executive order to remain closed. If a payment date is a
Legal Holiday at a place of payment, payment may be made at that place on the
next succeeding day that is not a Legal Holiday, and no interest shall accrue on
such payment for the intervening period.

     "Letter of Transmittal" means the letter of transmittal to be prepared by
the Company and sent to all Holders of the Notes for use by such Holders in
connection with the Exchange Offer.


<PAGE>
                                      -13-


     "Lien" means, with respect to any asset, any mortgage, lien, pledge,
charge, security interest or encumbrance of any kind in respect of such asset,
whether or not filed, recorded or otherwise perfected under applicable law,
including any conditional sale or other title retention agreement, any lease in
the nature thereof, any option or other agreement to sell or give a security
interest in and any filing of or agreement to give any financing statement under
the Uniform Commercial Code (or equivalent statutes) of any jurisdiction.

     "Measurement Date" means January 1, 1999.

     "Moody's" means Moody's Investors Service, Inc. or any successor to the
rating agency business thereof.

     "Net Income" means, with respect to any Person, the net income (loss) of
such Person and its Restricted Subsidiaries, determined in accordance with GAAP
and before any reduction in respect of preferred stock dividends, excluding,
however:

     (1)  any gain or loss, together with any related provision for taxes on
          such gain or loss, realized in connection with: (a) any Asset Sale; or
          (b) the disposition of any securities by such Person or any of its
          Restricted Subsidiaries or the extinguishment of any Indebtedness of
          such Person or any of its Restricted Subsidiaries; and

     (2)  any extraordinary gain or loss, together with any related provision
          for taxes on such extraordinary gain or loss.

     "Net Proceeds" means the aggregate cash proceeds received by the Company or
any of its Restricted Subsidiaries in respect of any Asset Sale (including,
without limitation, any cash received upon the sale or other disposition of any
non-cash consideration received in any Asset Sale), net of the direct costs
relating to such Asset Sale, including, without limitation, legal, accounting
and investment banking fees, and sales commissions, and any relocation expenses
incurred as a result thereof, taxes paid or payable as a result thereof, in each
case after taking into account any available tax credits or deductions and any
tax sharing arrangements and amounts required to be applied to the repayment of
Indebtedness secured by a Lien on the asset or assets that were the subject of
such Asset Sale.

     "Network" means the fiber optic telecommunications network constructed or
owned from time to time by the Company and its Restricted Subsidiaries.

     "Non-Competition Agreement" means that certain Letter to the Company from
Ledcor Inc., dated as of May 31, 1998, regarding Ledcor Inc.'s agreement not to
compete with the Company in the business of developing or constructing fiber
optic communications infrastructure.

     "Non-Recourse Debt" means Indebtedness:

     (1)  as to which neither the Company nor any of its Restricted Subsidiaries
          (a) provides credit support of any kind (including any undertaking,
          agreement or instrument that would constitute Indebtedness), (b) is
          directly or indirectly liable as a guarantor or otherwise, or (c)
          constitutes the lender; and

     (2)  no default with respect to which (including any rights that the
          holders thereof may have to take enforcement action against an
          Unrestricted Subsidiary) would permit upon notice, lapse of time or
          both any holder of any other Indebtedness (other than the Euro Notes,
          the Notes, the 1999 Notes, the 1998 Notes or the Credit Facilities) of
          the Company or any of its Restricted Subsidi-


<PAGE>
                                      -14-


          aries to declare a default on such other Indebtedness or cause the
          payment thereof to be accelerated or payable prior to its stated
          maturity.

     "Non-U.S. Person" means a Person who is not a U.S. Person.

     "Notes" has the meaning assigned to it in the preamble to this Indenture.

     "Obligations" means any principal, interest, penalties, fees,
indemnifications, reimbursements, damages and other liabilities payable under
the documentation governing any Indebtedness.

     "Offering" means the offering of the Notes by the Company.

     "Offering Memorandum" means that certain Offering Memorandum dated April
20, 2000 pursuant to which the Company offered the Notes and the Euro Notes.

     "Officer" means, with respect to any Person, the Chairman of the Board, the
Chief Executive Officer, the President, the Chief Operating Officer, the Chief
Financial Officer, the Treasurer, any Assistant Treasurer, the Controller, the
Secretary or any Vice-President of such Person.

     "Officers' Certificate" means a certificate signed on behalf of the Company
by two Officers of the Company, one of whom must be the principal executive
officer, the chief financial officer, or the treasurer of the Company, that
meets the requirements of Section 10.05 hereof.

     "Opinion of Counsel" means an opinion from legal counsel who is reasonably
acceptable to the Trustee, that meets the requirements of Section 10.05 hereof.
The counsel may be an employee of or counsel to the Company, any Subsidiary of
the Company or the Trustee.

     "Parent Companies" means Ledcor Inc., an Alberta corporation, Worldwide
Fiber Holdings Ltd., an Alberta corporation, Ledcor Industries Limited, an
Alberta corporation, Ledcor Limited Partnership, a limited partnership of which
Ledcor Industries Limited is the general partner, and Ledcom Holdings Ltd., an
Alberta corporation.

     "Participant" means, with respect to the Depositary, Euroclear or
Clearstream, a Person who has an account with the Depositary, Euroclear or
Clearstream, respectively (and, with respect to DTC, shall include Euroclear and
Clearstream).

     "Permitted Fiber Investment" means any Investment of up to 12 fibers on any
Segment of the Network.

     "Permitted Holder" means any Parent Company and its Affiliates.

     "Permitted Investments" means:

     (1)  any Investment in the Company or in any Restricted Subsidiary of the
          Company;

     (2)  any Investment in Cash Equivalents;

     (3)  any Investment by the Company or any Restricted Subsidiary of the
          Company in a Person, if as a result of such Investment:


<PAGE>
                                      -15-


          (a)  such Person becomes a Restricted Subsidiary of the Company; or

          (b)  such Person is merged, consolidated or amalgamated with or into,
               or transfers or conveys substantially all of its assets to, or is
               liquidated into, the Company or a Restricted Subsidiary of the
               Company;

     (4)  any Investment made as a result of the receipt of non-cash
          consideration from an Asset Sale that was made pursuant to and in
          compliance with the provisions of Section 4.10;

     (5)  any Investment made as a result of the receipt of non-cash
          consideration used or useful in a Telecommunications Business from any
          sale, lease, transfer, conveyance or other disposition of
          telecommunications capacity, transmission rights or other
          telecommunications services provided over the Company's network in the
          ordinary course of business which, if treated as an Asset Sale, would
          have been made in compliance with the provisions of Section 4.10;

     (6)  advances and loans to officers and employees of the Company or any
          Restricted Subsidiary in an amount not exceeding $5.0 million any one
          time outstanding;

     (7)  Investments in the form of intercompany Indebtedness to the extent
          permitted under clause (f) of the second paragraph of Section 4.09
          hereof;

     (8)  Hedging Obligations, provided that such Hedging Obligations constitute
          Permitted Indebtedness permitted by clause (g) of the second paragraph
          of Section 4.09 hereof;

     (9)  Investments of the Company or any Restricted Subsidiary existing on
          the Issue Date;

     (10) Investments in securities of trade creditors or customers received
          pursuant to any plan of reorganization or similar arrangement upon the
          bankruptcy or insolvency of such trade creditors or customers; and

     (11) other Investments in any Person having an aggregate fair market value
          (measured on the date each such Investment was made and without giving
          effect to subsequent changes in value), when taken together with all
          other Investments made pursuant to this clause (11) since the Issue
          Date, not to exceed the sum of $150 million plus $196,796,249.80.

     "Permitted Liens" means:

     (1)  Liens on the assets of the Company and any Restricted Subsidiary of
          the Company securing Indebtedness and other Obligations under Credit
          Facilities that are permitted by the terms of this Indenture to be
          incurred;

     (2)  Liens in favor of the Company or its Restricted Subsidiaries;

     (3)  Liens on property of a Person existing at the time such Person becomes
          a Restricted Subsidiary of the Company or is merged with or into or
          consolidated with the Company or any Restricted Subsidiary of the
          Company; provided that such Liens were in existence prior to the
          contemplation of such Person becoming a Restricted Subsidiary of the
          Company or merger or consolidation and do not extend to any assets
          other than those of such person or the Person merged into or
          consolidated with the Company or the Restricted Subsidiary;


<PAGE>
                                      -16-


     (4)  Liens on property existing at the time of acquisition thereof by the
          Company or any Restricted Subsidiary of the Company, provided that
          such Liens were in existence prior to the contemplation of such
          acquisition;

     (5)  Liens to secure the performance of statutory obligations, surety or
          appeal bonds, performance bonds or other obligations of a like nature
          incurred in the ordinary course of business;

     (6)  Liens to secure Purchase Money Indebtedness and Vendor Financing
          Indebtedness permitted by clause (d) of the second paragraph of
          Section 4.09 covering only the assets (or portion thereof) acquired
          with such Indebtedness;

     (7)  Liens existing on the Issue Date;

     (8)  Liens for taxes, assessments or governmental charges or claims that
          are not yet delinquent or that are being contested in good faith by
          appropriate proceedings promptly instituted and diligently concluded,
          provided that any reserve or other appropriate provision as shall be
          required in conformity with GAAP shall have been made therefor;

     (9)  Liens created for the benefit of the Notes and the Euro Notes;

     (10) Liens imposed by law or arising by operation of law, including,
          without limitation, landlords' mechanics', carriers' warehousemen's
          materialmen's, suppliers' and vendors' Liens, Liens for master's and
          crew's wages and other similar maritime Liens and mechanics' Liens, in
          each case which are incurred in the ordinary course of business for
          sums not yet delinquent or being contested in good faith, if such
          reserves or other appropriate provisions, if any, as shall be required
          by GAAP shall have been made with respect thereto;

     (11) zoning restrictions, easements, license, covenants, reservations,
          restrictions on the use of real property and defects, irregularities
          and deficiencies in title to real property that do not, individually
          or in the aggregate, materially affect the ability of the Company or
          any Restricted Subsidiary to conduct its business and are incurred in
          the ordinary course of business;

     (12) Liens incurred or pledges and deposits made in the ordinary course of
          business in connection with workers' compensation and unemployment
          insurance and other types of social security;

     (13) Liens to secure any extension, renewal, refinancing or refunding (or
          successive extensions, renewals, refinancings or refundings), in whole
          or in part, of any Indebtedness secured by Liens referred to in the
          foregoing clauses (3), (4), (6), and (7) of this definition, provided
          that such Liens do not extend to any other property of the Company or
          any Restricted Subsidiary and the principal amount of the Indebtedness
          secured by such Lien is not increased;

     (14) judgment Liens not giving rise to an Event of Default so long as such
          Lien is adequately bonded and any appropriate legal proceedings that
          may have been initiated for the review of such judgment, decree or
          order shall not have been finally terminated or the period within
          which such proceedings may be initiated shall not have expired;

     (15) Liens securing obligations of the Company under Hedging Obligations
          permitted to be incurred under clause (g) of the second paragraph of
          Section 4.09 or any collateral for the Indebtedness to which such
          Hedging Obligations relate;


<PAGE>
                                      -17-


     (16) Liens upon specific items of inventory or other goods and proceeds of
          any Person securing such Person's obligations in respect of banker's
          acceptances issued or credited for the account of such Person to
          facilitate the purchase, shipment or storage of such inventory or
          other goods;

     (17) Liens securing reimbursement obligations with respect to commercial
          letters of credit which encumber documents and other property relating
          to such letters of credit and products and proceeds thereof;

     (18) Liens encumbering deposits made to secure obligations arising from
          statutory, regulatory, contractual, or warranty requirements of the
          Company or any of its Restricted Subsidiaries, including rights of
          offset and set-off;

     (19) Liens arising out of consignment or similar arrangements for the sale
          of goods in the ordinary course of business;

     (20) any interest or title of a lessor in the Property subject to any lease
          other than a Capital Lease;

     (21) leases or subleases granted to others that do not materially interfere
          with the ordinary course of business of the Company and its Restricted
          Subsidiaries;

     (22) Liens encumbering Property or other assets under construction arising
          from progress or partial payments by a customer or the company or its
          Restricted Subsidiaries relating to such Property or other assets;

     (23) Liens arising from filing Uniform Commercial Code financing statements
          regarding leases, provided that such Liens do not extend to any
          property or assets which are not leased property subject to such
          leases or subleases;

     (24) 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;

     (25) Liens securing Permitted ROW Indebtedness;

     (26) Liens securing other Indebtedness not exceeding $5.0 million at any
          time outstanding;

     (27) Liens incurred in the ordinary course of business of the Company or
          any Restricted Subsidiary of the Company with respect to obligations
          that do not exceed $5.0 million at any one time outstanding and that
          (a) are not incurred in connection with the borrowing of money or the
          obtaining of advances or credit (other than trade credit in the
          ordinary course of business) and (b) do not in the aggregate
          materially detract from the value of the property or materially impair
          the use thereof in the operation of business by the Company or such
          Restricted Subsidiary;

     (28) Liens securing Qualified Subsidiary Indebtedness to the extent
          permitted to be incurred by clause (h) of the second paragraph of
          Section 4.09 hereof; and

     (29) Liens securing Indebtedness which does not exceed 1.5 times the
          Company's Consolidated Cash Flow.


<PAGE>
                                      -18-


     "Permitted Project Financing Investment" means an Investment by the Company
or any Restricted Subsidiary in any Unrestricted Subsidiary for the purpose of
facilitating the incurrence by such Unrestricted Subsidiary of Non-Recourse Debt
for the purpose of financing a portion of the cost of construction, engineering,
acquisition, installation, development or improvement by such Unrestricted
Subsidiary of any Segment of the Network; provided, however, that the amount of
any such Investment shall not exceed 55% of the total initial capitalization of
any such Unrestricted Subsidiary.

     "Permitted Refinancing Indebtedness" means any Indebtedness of the Company
or any of its Restricted Subsidiaries issued in exchange for, or the net
proceeds of which are used to extend, refinance, renew, replace, defease or
refund other Indebtedness of the Company or any of its Restricted Subsidiaries
(other than intercompany Indebtedness); provided that:

     (1)  the principal amount (or accreted value, if applicable) of such
          Permitted Refinancing Indebtedness does not exceed the principal
          amount of (or accreted value, if applicable), plus accrued interest
          on, the Indebtedness so extended, refinanced, renewed, replaced,
          defeased or refunded (plus the amount of reasonable expenses incurred
          in connection therewith);

     (2)  such Permitted Refinancing Indebtedness has a final maturity date
          equal to or later than the final maturity date of, and has a Weighted
          Average Life to Maturity equal to or greater than the Weighted Average
          Life to Maturity of, the Indebtedness being extended, refinanced,
          renewed, replaced, defeased or refunded;

     (3)  if the Indebtedness being extended, refinanced, renewed, replaced,
          defeased or refunded is subordinated in right of payment to the Notes,
          such Permitted Refinancing Indebtedness has a final maturity date
          equal to or later than the final maturity date of, and is subordinated
          in right of payment to, the Notes on terms at least as favorable to
          the Holders of Notes as those contained in the documentation governing
          the Indebtedness being extended, refinanced, renewed, replaced,
          defeased or refunded; and

     (4)  such Indebtedness is incurred either by the Company or by the
          Restricted Subsidiary who is the obligor on the Indebtedness being
          extended, refinanced, renewed, replaced, defeased or refunded.

     "Permitted ROW Indebtedness" means Indebtedness evidencing the deferred
obligation to the seller of any ROW on which any Segment of the Company's
Network is being constructed to pay the purchase price for such ROW; provided,
however, that in no event shall the aggregate principal amount of any such
Indebtedness exceed, with respect to any Segment of the Network, more than 50%
of the total anticipated construction cost of such Segment, as determined by the
Board of Directors in good faith.

     "Permitted Telecommunications Asset Disposition" means the transfer,
conveyance, sale, lease, grant of an IRU or other disposition (each, a
"Disposition") in the ordinary course of business of dark fiber, conduit or
associated infrastructure of the Network, (i) the proceeds of which are treated
as revenues by the Company in accordance with GAAP and (ii) that, in the case of
the sale of dark fiber, would not result in the Company retaining less than (x)
24 fibers per route mile or (y) 12 fibers and one empty conduit per route mile,
in each case, on every Segment of the Network constructed or developed by the
Company (other than the Canadian FOTS in which the Company shall only be
required to retain six fibers per route mile on each Segment), provided,
however, that any Permitted Fiber Investment that results in the Company
retaining a minimum of 12 fibers per route mile (in the case of clause (x)
above) or one empty conduit (in the case of clause (y) above) shall be deemed to

<PAGE>
                                      -19-


be a Permitted Telecommunications Asset Disposition; provided further that any
subsequent Disposition of such Permitted Fiber Investment shall be deemed to be
an Asset Sale.

     "Permitted Vendor Facilities" means Vendor Financing Indebtedness that is
permitted to include working capital facilities.

     "Person" means any individual, corporation, partnership, joint venture,
association, limited liability company, joint stock company, trust,
unincorporated organization, government or agency or political subdivision
thereof or any other entity.

     "Private Placement Legend" means the legend set forth in Section 2.06(g)(i)
to be placed on all Notes issued under this Indenture except where otherwise
permitted by the provisions of this Indenture.

     "Property" means, with respect to any Person, any interest of such Person
in any kind of property or asset, whether real, personal or mixed, or tangible
or intangible, including Capital Stock in, and other securities of, any other
Person.

     "Public Equity Offering" means any underwritten public offering of common
stock of the Company in which the gross proceeds to the Company are at least
$100.0 million.

     "Purchase Money Indebtedness" means Indebtedness of the Company (including
Acquired Indebtedness and Capital Lease Obligations, mortgage financings and
purchase money obligations) incurred for the purpose of financing all or any
part of the cost of construction, engineering, acquisition, installation,
development or improvement by the Company or any Restricted Subsidiary of any
Telecommunications Assets of the Company or any Restricted Subsidiary and
including any related notes, Guarantees, collateral documents, instruments and
agreements executed in connection therewith, as the same may be amended,
supplemented, modified or restated from time to time.

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

     "Qualified Equity Offering" means (A) any underwritten public offering
(other than on Form S-4 or S-8 or any successor forms thereto) of common stock
of the Company in which the gross proceeds to the Company are at least $100.0
million; provided, however, that the Concurrent Equity Offering shall not be
deemed to be a Qualified Equity Offering, or (B) the sale by the Company of its
Equity Interests to any Strategic Equity Investor, the net proceeds of which are
at least $25.0 million.

     "Qualified Subsidiary Indebtedness" means Indebtedness of any Restricted
Subsidiary under one or more senior credit agreements, senior secured loan
agreements or similar senior credit facilities (including any supply or similar
agreement under which the goods to be financed were obtained) entered into from
time to time, including related notes, guarantees, collateral documents,
instruments and agreements executed in connection therewith.

     "Registration Rights Agreement" means the A/B Exchange Registration Rights
Agreement, dated as of April 26, 2000, by and among the Company, Donaldson,
Lufkin & Jenrette Securities Corporation, Goldman Sachs & Co., Bear, Stearns &
Co. Inc., Chase Securities Inc., Credit Suisse First Boston Corporation, Morgan
Stanley & Co. Incorporated, Salomon Smith Barney Inc., RBC Dominion Securities
Corporation and TD Securities (USA) Inc., as such agreement may be amended,
modified or supplemented from time to time.

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


<PAGE>
                                      -20-


     "Regulation S Global Note" means a global Note bearing the Private
Placement Legend and deposited with or on behalf of the Depositary and
registered in the name of the Depositary or its nominee, issued in a
denomination equal to the outstanding principal amount of the Notes initially
sold in reliance on Rule 903 of Regulation S.

     "Responsible Officer," when used with respect to the Trustee, means any
officer within the Corporate Trust Department of the Trustee (or any successor
group of the Trustee) with direct responsibility for the administration of this
Indenture and also means, with respect to a particular corporate trust matter,
any other officer to whom such matter is referred because of his knowledge of
and familiarity with the particular subject.

     "Restricted Definitive Note" means a Definitive Note bearing the Private
Placement Legend.

     "Restricted Global Note" means a Global Note bearing the Private Placement
Legend.

     "Restricted Investment" means an Investment other than a Permitted
Investment.

     "Restricted Subsidiary" of a Person means any Subsidiary of the referent
Person that is not an Unrestricted Subsidiary.

     "ROW" means Rights-of-way, licenses and permits (creating a contractual
interest and not an interest in land) from third party landowners and
governmental authorities which permit the holder to install conduit and fiber.

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

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

     "Rule 903" means Rule 903 promulgated under the Securities Act.

     "Rule 904" means Rule 904 promulgated the Securities Act.

     "S&P" means Standard & Poor's Ratings Group, a division of McGraw Hill,
Inc., or any successor to the rating agency business thereof.

     "SEC" means the Securities and Exchange Commission.

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

     "Segment" means (x) with respect to the intercity portions of the Network,
the through-portion of the Network between two local networks and (y) with
respect to a local portion of the Network, the entire through-portion of the
Network, excluding the spurs which branch off the through-portion.

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

     "Significant Subsidiary" means any Subsidiary that would be a "significant
subsidiary" as defined in Article 1, Rule 1-02 of Regulation S-X, promulgated
pursuant to the Securities Act, as such Regulation is in effect on the date
hereof.


<PAGE>
                                      -21-


     "Stated Maturity" means, with respect to any installment of interest or
principal on any series of Indebtedness, the date on which such payment of
interest or principal was scheduled to be paid in the original documentation
governing such Indebtedness, and shall not include any contingent obligations to
repay, redeem or repurchase any such interest or principal prior to the date
originally scheduled for the payment thereof.

     "Strategic Equity Investor" means a corporation, partnership or other
entity engaged in one or more Telecommunications Businesses that has 80% or more
of the voting power of its Capital Stock owned by a Person or Persons that has
or have, as the case may be, at the time of the initial investment in the
Company, an equity market capitalization in excess of $1.0 billion; provided
that in no event shall any Affiliate of the Company (immediately prior to the
time of such investment) be eligible to be a Strategic Equity Investor.

     "Subsidiary" means, with respect to any Person:

     (1)  any corporation a majority of whose Capital Stock with voting power,
          under ordinary circumstances, to elect directors is, at the date of
          determination, directly or indirectly, owned by such Person (a
          "subsidiary"), by one or more subsidiaries of such Person or by such
          Person and one or more subsidiaries of such Person;

     (2)  a partnership in which such Person or a subsidiary of such Person is,
          at the date of determination, a general partner of such partnership;
          or

     (3)  any partnership, limited liability company or other Person in which
          such Person, a subsidiary of such Person or such Person and one or
          more subsidiaries of such Person, directly or indirectly, at the date
          of determination, has (x) at least a majority ownership interest or
          (y) the power to elect or appoint or direct the election or
          appointment of the managing partner or member of such Person or, if
          applicable, a majority of the directors or other governing body of
          such Person.

     "Tax" shall mean any tax, duty, levy, impost, assessment or other
governmental charge (including penalties, interest and any other liabilities
related thereto).

     "Telecommunications Assets" means all assets, rights (contractual or
otherwise) and properties, whether tangible or intangible, used or intended for
use in connection with a Telecommunications Business and the Equity Interests or
Indebtedness of a Person engaged primarily in a Telecommunications Business.

     "Telecommunications Business" means the business of (i) transmitting, or
providing services relating to the transmission of, voice, video or data through
owned or leased terrestrial or submarine transmission facilities and (ii)
constructing, installing, maintaining, creating, developing or marketing
terrestrial or submarine communications related network infrastructure,
components, equipment, software and other devices for use in a
telecommunications business and any other business or opportunity that is
reasonably related or complementary thereto; provided that the determination of
what constitutes a Telecommunications Business shall be made in good faith by
the Board of Directors.

     "TIA" means the Trust Indenture Act of 1939 (15 U.S.C. ss.ss. 77aaa-77bbbb)
as in effect on the date on which this Indenture is qualified under the TIA;
provided, however, that in the event the Trust Indenture Act of 1939 is amended
after such date, then "TIA" means, to the extent required by such amendment, the
Trust Indenture Act of 1939 as so amended.


<PAGE>
                                      -22-


     "Trustee" means HSBC Bank USA until a successor replaces HSBC Bank USA in
accordance with the applicable provisions of this Indenture and thereafter means
the successor serving hereunder.

     "Undertaking Agreements" means those certain Undertaking Agreements dated
as of May 31, 1998 between the Company (formerly known as Starfiber Inc.) and
786522 Alberta Ltd. pursuant to which 786522 Alberta Ltd. agreed to contribute
12 fiber strands on the Canadian FOTS to the Company in exchange for the
issuance of certain Capital Stock and the Agreement, dated May 28, 1999, as
amended, between the Company and certain affiliates of Ledcor Inc. whereby the
Company agreed to acquire certain fiber optic assets.

     "Unrestricted Definitive Note" means one or more Definitive Notes that do
not bear and are not required to bear the Private Placement Legend.

     "Unrestricted Global Note" means a permanent global Note substantially in
the form of Exhibit A attached hereto that bears the Global Note Legend and that
has the "Schedule of Exchanges of Interests in the Global Note" attached
thereto, and that is deposited with or on behalf of and registered in the name
of the Depositary, representing Notes that do not bear the Private Placement
Legend.

     "Unrestricted Subsidiary" means any Subsidiary of the Company that is
designated by the Board of Directors as an Unrestricted Subsidiary pursuant to a
Board Resolution, but only to the extent that such Subsidiary:

     (1)  has no Indebtedness other than Non-Recourse Debt;

     (2)  is not party to any agreement, contract, arrangement or understanding
          with the Company or any Restricted Subsidiary of the Company unless
          the terms of any such agreement, contract, arrangement or
          understanding are no less favorable to the Company or such Restricted
          Subsidiary than those that might be obtained at the time from Persons
          who are not Affiliates of the Company;

     (3)  is a Person with respect to which neither the Company nor any of its
          Restricted Subsidiaries has any direct or indirect obligation to
          maintain or preserve such Person's financial condition or to cause
          such Person to achieve any specified levels of operating results;

     (4)  has not guaranteed or otherwise directly or indirectly provided credit
          support for any Indebtedness of the Company or any of its Restricted
          Subsidiaries; and

     (5)  has at least one director on its board of directors that is not a
          director or executive officer of the Company or any of its Restricted
          Subsidiaries and has at least one executive officer that is not a
          director or executive officer of the Company or any of its Restricted
          Subsidiaries.

     Any designation of a Subsidiary of the Company as an Unrestricted
Subsidiary shall be evidenced to the Trustee by filing with the Trustee a
certified copy of the Board Resolution giving effect to such designation and an
Officers' Certificate certifying that such designation complied with the
preceding conditions and was permitted by the provisions of Section 4.07. If, at
any time, any Unrestricted Subsidiary would fail to meet the preceding
requirements as an Unrestricted Subsidiary, it shall thereafter cease to be an
Unrestricted Subsidiary for purposes of this Indenture and any Indebtedness of
such Subsidiary shall be deemed to be incurred by a Restricted Subsidiary of the
Company as of such date and, if such Indebtedness is not permitted to be
incurred as of such date under Section 4.09, the Company shall be in default of
such covenant. The Board of Directors may at any time designate any Unrestricted
Subsidiary to be a Restricted Subsidiary; provided that such designation shall
be deemed to be an incurrence of Indebtedness by a Restricted Subsidiary of the
Company of any outstanding In-


<PAGE>
                                      -23-


debtedness of such Unrestricted Subsidiary and such designation shall only be
permitted if (1) such Indebtedness is permitted under the provisions of Section
4.09 hereof, calculated on a pro forma basis as if such designation had occurred
at the beginning of the four-quarter reference period; and (2) no Default or
Event of Default would be in existence following such designation.

     "U.S. Person" means a U.S. person as defined in Rule 902(o) under the
Securities Act.

     "Vendor Financing Indebtedness" means Indebtedness of the Company incurred
pursuant to any agreements between the Company and one or more vendors or
lessors (or any Affiliate of any such vendor or lessor) of Telecommunications
Assets used or intended for use in a Telecommunications Business by the Company
providing financing for all or any part of the cost of construction,
engineering, acquisition, installation, development or improvement by the
Company or any Restricted Subsidiary of any Telecommunications Assets from any
such vendor or lessor (or any Affiliate of such vendor or lessor) and including
any related notes, Guarantees, collateral documents, instruments and agreements
executed in connection therewith, as the same may be amended, supplemented,
modified or restated from time to time. Vendor Financing Indebtedness shall not
include any working capital facility or Indebtedness to fund interest or other
similar expenses made available by any vendor or lessor.

     "Voting Stock" of any Person as of any date means the Capital Stock of such
Person that is at the time entitled to vote in the election of the board of
directors of such Person.

     "Weighted Average Life to Maturity" means, when applied to any Indebtedness
at any date, the number of years obtained by dividing:

     (1)  the sum of the products obtained by multiplying (a) the amount of each
          then remaining installment, sinking fund, serial maturity or other
          required payments of principal, including payment at final maturity,
          in respect thereof, by (b) the number of years (calculated to the
          nearest one-twelfth) that will elapse between such date and the making
          of such payment; by

     (2)  the then outstanding principal amount of such Indebtedness.

     "Wholly-Owned Restricted Subsidiary" of any Person means a Restricted
Subsidiary of such Person all of the outstanding Capital Stock or other
ownership interests of which (other than directors' qualifying shares) shall at
the time be owned by such Person and/or by one or more Wholly-Owned Restricted
Subsidiaries of such Person.

Section 1.02.     Other Definitions.

                                                                   Defined in
       Term                                                         Section
       ----                                                         -------

       "Additional Amounts"......................................     4.05
       "Affiliate Transaction"...................................     4.11
       "Agreement Currency"......................................     6.12
       "Asset Sale Offer"........................................     3.09
       "Authentication Order"....................................     2.02
       "Change of Control Offer".................................     4.14
       "Change of Control Payment"...............................     4.14
       "Change of Control Payment Date"..........................     4.14
       "Covenant Defeasance".....................................     8.03
       "DTC".....................................................     2.03

<PAGE>
                                      -24-

                                                                   Defined in
       Term                                                         Section
       ----                                                         -------

       "Event of Default"........................................     6.01
       "Guaranteed Indebtedness".................................     4.16
       "incur"...................................................     4.09
       "Judgment Currency".......................................     6.12
       "Legal Defeasance"........................................     8.02
       "Offer Amount"............................................     3.09
       "Offer Period"............................................     3.09
       "Paying Agent"............................................     2.03
       "Payment Default".........................................     6.01
       "Permitted Debt"..........................................     4.09
       "Process Agent"...........................................    10.09
       "Purchase Date"...........................................     3.09
       "Reference Period"........................................     4.09
       "Registrar"...............................................     2.03
       "Restricted Payments".....................................     4.07
       "Subsidiary Guarantee"....................................     4.16

Section 1.03.     Incorporation by Reference of Trust Indenture Act.

     Whenever this Indenture refers to a provision of the TIA, the provision is
incorporated by reference in and made a part of this Indenture.

     The following TIA terms used in this Indenture have the following meanings:

     "indenture securities" means the Notes;

     "indenture security Holder" means a Holder of a Note;

     "indenture to be qualified" means this Indenture;

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

     "obligor" on the Notes means the Company and any successor obligor upon the
Notes.

     All other terms used in this Indenture that are defined by the TIA, defined
by TIA reference to another statute or defined by SEC rule under the TIA have
the meanings so assigned to them.

Section 1.04.     Rules of Construction.

     (a) Unless the context otherwise requires:

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

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

          (3)  "or" is not exclusive;


<PAGE>
                                      -25-


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

          (5)  provisions apply to successive events and transactions;

          (6)  references to sections of or rules under the Securities Act shall
               be deemed to include substitute, replacement of successor
               sections or rules adopted by the SEC from time to time; and

          (7)  references to dollars or $ mean legal currency of the United
               States of America.

     (b) Whenever in this Indenture there is mentioned, in any context, the
payment of principal, premium, if any, redemption price, Change of Control
Payment, offer price or interest, or any other amount payable under or with
respect to any Note, such mention shall be deemed to include mention of the
payment of Additional Amounts to the extent that, in such context, Additional
Amounts are, were or would be payable in respect thereof.

                                    ARTICLE 2
                                    THE NOTES

Section 2.01.     Form and Dating.

     (a) General. The Notes and the Trustee's certificate of authentication
thereon shall be substantially in the form of Exhibit A hereto. The Notes may
have notations, legends or endorsements required by law, stock exchange rule or
usage. Each Note shall be dated the date of its authentication. The Notes shall
be in denominations of $1,000 and integral multiples thereof.

     The terms and provisions contained in the Notes shall constitute, and are
hereby expressly made, a part of this Indenture and the Company and the Trustee,
by their execution and delivery of this Indenture, expressly agree to such terms
and provisions and to be bound thereby. However, to the extent any provision of
any Note conflicts with the express provisions of this Indenture, the provisions
of this Indenture shall govern and be controlling.

     (b) Global Notes. Notes issued in global form shall be substantially in the
form of Exhibit A hereto (including the Global Note Legend thereon and the
"Schedule of Exchanges of Interests in the Global Note" attached thereto). Notes
issued in definitive form shall be substantially in the form of Exhibit A hereto
(but without the Global Note Legend thereon and without the "Schedule of
Exchanges of Interests in the Global Note" attached thereto). Each Global Note
shall represent such of the outstanding Notes as shall be specified therein and
each shall provide that it shall represent the aggregate principal amount of
outstanding Notes from time to time endorsed thereon and that the aggregate
principal amount of outstanding Notes represented thereby may from time to time
be reduced or increased, as appropriate, to reflect exchanges and redemptions.
Any endorsement of a Global Note to reflect the amount of any increase or
decrease in the aggregate principal amount of outstanding Notes represented
thereby shall be made by the Trustee or the Custodian, at the direction of the
Trustee, in accordance with instructions given by the Holder thereof as required
by Section 2.06 hereof.

     (c) Euroclear and Clearstream Procedures Applicable. The provisions of the
"Operating Procedures of the Euroclear System" and "Terms and Conditions
Governing Use of Euroclear" and the "General Terms and Conditions of
Clearstream" and "Customer Handbook" of Clearstream shall be applicable to
transfers of beneficial interests in the Regulation S Global Notes that are held
by Participants through Euroclear or Clearstream.


<PAGE>
                                      -26-


Section 2.02.     Execution and Authentication.

     One Officer shall sign the Notes for the Company by manual or facsimile
signature.

     If an Officer whose signature is on a Note no longer holds that office at
the time a Note is authenticated, the Note shall nevertheless be valid.

     A Note shall not be valid until authenticated by the manual signature of
the Trustee. The signature shall be conclusive evidence that the Note has been
authenticated under this Indenture.

     The Trustee shall, upon a written order of the Company signed by an Officer
(an "Authentication Order"), authenticate Notes for original issue up to the
aggregate principal amount of Notes stated in paragraph 4 of the Notes. The
aggregate principal amount of Notes outstanding at any time may not exceed such
amount except as provided in Section 2.07 hereof.

     The Trustee may appoint an authenticating agent acceptable to the Company
to authenticate Notes. An authenticating agent may authenticate Notes whenever
the Trustee may do so. Each reference in this Indenture to authentication by the
Trustee includes authentication by such agent. An authenticating agent has the
same rights as an Agent to deal with Holders or an Affiliate of the Company.

Section 2.03.     Registrar and Paying Agent.

     The Company shall maintain an office or agency where Notes may be presented
for registration of transfer or for exchange ("Registrar") and an office or
agency where Notes may be presented for payment ("Paying Agent"). The Registrar
shall keep a register of the Notes and of their transfer and exchange. For so
long as the Notes are listed on the Luxembourg Stock Exchange and the rules of
such stock exchange so require, the Company will maintain a Paying Agent in
Luxembourg. If a payment date is not a Business Day at a place of payment,
payment may be made at that place on the next succeeding Business Day and no
interest shall accrue with respect to such payment for the intervening period.
The term "Registrar" includes any co-registrar and the term "Paying Agent"
includes any additional paying agent. The Company shall notify the Trustee in
writing of the name and address of any Agent not a party to this Indenture. If
the Company fails to appoint or maintain another entity as Registrar or Paying
Agent, the Trustee shall act as such. The Company or any of its Subsidiaries may
act as Paying Agent or Registrar.

     The Company initially appoints The Depository Trust Company ("DTC") to act
as Depositary with respect to the Global Notes.

     The Company initially appoints the Trustee to act as the principal
Registrar and Paying Agent and to act as Custodian with respect to the Global
Notes at its office in New York, and Banque Generale du Luxembourg to initially
act as an additional Paying Agent in Luxembourg. The Company may change the
Paying Agent or Registrar without prior notice to the Holders, and the Company
or any of its Subsidiaries may act as Paying Agent or Registrar; provided,
however, that for so long as any Notes are listed on the Luxembourg Stock
Exchange and the rules of such exchange so require, the Company will publish
notice of the change in the Paying Agent in Luxembourg in a daily newspaper with
general circulation in Luxembourg (which is expected to be the Luxemburger
Wort). Any notice regarding Notes to be published in Luxembourg will be
published in the same manner.


<PAGE>
                                      -27-


Section 2.04.     Paying Agent to Hold Money in Trust.

     The Company shall require each Paying Agent other than the Trustee to agree
in writing that the Paying Agent shall hold in trust for the benefit of Holders
or the Trustee all money held by the Paying Agent for the payment of principal,
premium, if any, or interest on the Notes, and shall notify the Trustee of any
default by the Company in making any such payment. While any such default
continues, the Trustee may require a Paying Agent to pay all money held by it to
the Trustee. The Company at any time may require a Paying Agent to pay all money
held by it to the Trustee. Upon payment over to the Trustee, the Paying Agent
(if other than the Company or a Subsidiary) shall have no further liability for
the money. If the Company or a Subsidiary acts as Paying Agent, it shall
segregate and hold in a separate trust fund for the benefit of the Holders all
money held by it as Paying Agent. Upon any bankruptcy or reorganization
proceedings relating to the Company, the Trustee shall serve as Paying Agent for
the Notes.

Section 2.05.     Holder Lists.

     The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of
all Holders and shall otherwise comply with TIA ss. 312(a). If the Trustee is
not the Registrar, the Company shall furnish to the Trustee at least seven
Business Days before each interest payment date and at such other times as the
Trustee may request in writing, a list in such form and as of such date as the
Trustee may reasonably require of the names and addresses of the Holders of
Notes and the Company shall otherwise comply with TIA ss. 312(a).

Section 2.06.     Transfer and Exchange.

     (a) Transfer and Exchange of Global Notes. A Global Note may not be
transferred as a whole except by the Depositary to a nominee of the Depositary,
by a nominee of the Depositary to the Depositary or to another nominee of the
Depositary, or by the Depositary or any such nominee to a successor Depositary
or a nominee of such successor Depositary. All Global Notes shall be exchanged
by the Company for Definitive Notes if:

          (i) the Company delivers to the Trustee notice from the Depositary
     that it is unwilling or unable to continue to act as Depositary or that it
     is no longer a clearing agency registered under the Exchange Act and, in
     either case, a successor Depositary is not appointed by the Company within
     120 days after the date of such notice from the Depositary; or

          (ii) the Company in its sole discretion determines that the Global
     Notes (in whole but not in part) should be exchanged for Definitive Notes
     and delivers a written notice to such effect to the Trustee.

     Upon the occurrence of either of the preceding events in (i) or (ii) above,
Definitive Notes shall be issued in such names as the Depositary shall instruct
the Trustee. Global Notes also may be exchanged or replaced, in whole or in
part, as provided in Sections 2.07 and 2.10 hereof. Every Note authenticated and
delivered in exchange for, or in lieu of, a Global Note or any portion thereof,
pursuant to this Section 2.06 or Section 2.07 or 2.10 hereof, shall be
authenticated and delivered in the form of, and shall be, a Global Note. A
Global Note may not be exchanged for another Note other than as provided in this
Section 2.06(a), however, beneficial interests in a Global Note may be
transferred and exchanged as provided in Section 2.06(b), (c) or (f) hereof.

     (b) Transfer and Exchange of Beneficial Interests in the Global Notes. The
transfer and exchange of beneficial interests in the Global Notes shall be
effected through the Depositary, in accordance with the provi-


<PAGE>
                                      -28-


sions of this Indenture and the Applicable Procedures. Beneficial interests in
the Restricted Global Notes shall be subject to restrictions on transfer
comparable to those set forth herein to the extent required by the Securities
Act. Transfers of beneficial interests in the Global Notes also shall require
compliance with either subparagraph (i) or (ii) below, as applicable, as well as
one or more of the other following subparagraphs, as applicable:

          (i) Transfer of Beneficial Interests in the Same Global Note.
     Beneficial interests in any Restricted Global Note may be transferred to
     Persons who take delivery thereof in the form of a beneficial interest in
     the same Restricted Global Note in accordance with the transfer
     restrictions set forth in the Private Placement Legend. Beneficial
     interests in any Unrestricted Global Note may be transferred to Persons who
     take delivery thereof in the form of a beneficial interest in an
     Unrestricted Global Note. No written orders or instructions shall be
     required to be delivered to the Registrar to effect the transfers described
     in this Section 2.06(b)(i).

          (ii) All Other Transfers and Exchanges of Beneficial Interests in
     Global Notes. In connection with all transfers and exchanges of beneficial
     interests that are not subject to Section 2.06(b)(i) above, the transferor
     of such beneficial interest must deliver to the Registrar either:

               (A)(1) a written order from a Participant or an Indirect
          Participant given to the Depositary in accordance with the Applicable
          Procedures directing the Depositary to credit or cause to be credited
          a beneficial interest in another Global Note in an amount equal to the
          beneficial interest to be transferred or exchanged; and,

               (A)(2) instructions given in accordance with the Applicable
          Procedures containing information regarding the Participant account to
          be credited with such increase; or,

               (B)(1) a written order from a Participant or an Indirect
          Participant given to the Depositary in accordance with the Applicable
          Procedures directing the Depositary to cause to be issued a Definitive
          Note in an amount equal to the beneficial interest to be transferred
          or exchanged; and,

               (B)(2) instructions given by the Depositary to the Registrar
          containing information regarding the Person in whose name such
          Definitive Note shall be registered to effect the transfer or exchange
          referred to in (1) above.

          Upon consummation of an Exchange Offer by the Company in accordance
     with Section 2.06(f) hereof, the requirements of this Section 2.06(b)(ii)
     shall be deemed to have been satisfied upon receipt by the Registrar of the
     instructions contained in the Letter of Transmittal delivered by the holder
     of such beneficial interests in the Restricted Global Notes. Upon receipt
     of an Opinion of Counsel as to the satisfaction of all of the requirements
     for transfer or exchange of beneficial interests in Global Notes contained
     in this Indenture and the Notes or otherwise applicable under the
     Securities Act, the Trustee shall adjust the principal amount of the
     relevant Global Note(s) pursuant to Section 2.06(h) hereof.

          (iii) Transfer of Beneficial Interests to Another Restricted Global
     Note. A beneficial interest in any Restricted Global Note may be
     transferred to a Person who takes delivery thereof in the form of a
     beneficial interest in another Restricted Global Note if the transfer
     complies with the requirements of Section 2.06(b)(ii) above and the
     Registrar receives the following:

               (A) if the transferee will take delivery in the form of a
          beneficial interest in the 144A Global Note, then the transferor must
          deliver a certificate in the form of Exhibit B hereto, including the
          certifications in item (1) thereof; and


<PAGE>
                                      -29-


               (B) if the transferee will take delivery in the form of a
          beneficial interest in the Regulation S Global Note, then the
          transferor must deliver a certificate in the form of Exhibit B hereto,
          including the certifications in item (2) thereof;

                    (iv) Transfer and Exchange of Beneficial Interests in a
               Restricted Global Note for Beneficial Interests in the
               Unrestricted Global Note. A beneficial interest in any Restricted
               Global Note may be exchanged by any holder thereof for a
               beneficial interest in an Unrestricted Global Note or transferred
               to a Person who takes delivery thereof in the form of a
               beneficial interest in an Unrestricted Global Note if the
               exchange or transfer complies with the requirements of Section
               2.06(b)(ii) above and:

                         (A) such exchange or transfer is effected pursuant to
                    the Exchange Offer in accordance with the Registration
                    Rights Agreement and the holder of the beneficial interest
                    to be transferred, in the case of an exchange, or the
                    transferee, in the case of a transfer, certifies in the
                    applicable Letter of Transmittal that it is not (1) a
                    broker-dealer, (2) a Person participating in the
                    distribution of the Exchange Notes or (3) a Person who is an
                    affiliate (as defined in Rule 144) of the Company;

                         (B) such transfer is effected pursuant to the Shelf
                    Registration Statement in accordance with the Registration
                    Rights Agreement;

                         (C) such transfer is effected by a Broker-Dealer
                    pursuant to the Exchange Offer Registration Statement in
                    accordance with the Registration Rights Agreement; or

                         (D) the Registrar receives the following:

                         (1) if the holder of such beneficial interest in a
                    Restricted Global Note proposes to exchange such beneficial
                    interest for a beneficial interest in an Unrestricted Global
                    Note, a certificate from such holder in the form of Exhibit
                    C hereto, including the certifications in item (1)(a)
                    thereof; or

                         (2) if the holder of such beneficial interest in a
                    Restricted Global Note proposes to transfer such beneficial
                    interest to a Person who shall take delivery thereof in the
                    form of a beneficial interest in an Unrestricted Global
                    Note, a certificate from such holder in the form of Exhibit
                    B hereto, including the certifications in item (4) thereof;

     and, in each such case set forth in this subparagraph (D), if the Registrar
     so requests or if the Applicable Procedures so require, an Opinion of
     Counsel in form reasonably acceptable to the Registrar to the effect that
     such exchange or transfer is in compliance with the Securities Act and that
     the restrictions on transfer contained herein and in the Private Placement
     Legend are no longer required in order to maintain compliance with the
     Securities Act.

     If any such transfer is effected pursuant to subparagraph (B) or (D) above
     at a time when an Unrestricted Global Note has not yet been issued, the
     Company shall issue and, upon receipt of an Authentication Order in
     accordance with Section 2.02 hereof, the Trustee shall authenticate one or
     more Unrestricted Global Notes in an aggregate principal amount equal to
     the aggregate principal amount of beneficial interests transferred pursuant
     to subparagraph (B) or (D) above.

     Beneficial interests in an Unrestricted Global Note cannot be exchanged
     for, or transferred to Persons who take delivery thereof in the form of, a
     beneficial interest in a Restricted Global Note.


<PAGE>
                                      -30-


     (c) Transfer or Exchange of Beneficial Interests for Definitive Notes.

               (i) Beneficial Interests in Restricted Global Notes to Restricted
          Definitive Notes. If any holder of a beneficial interest in a
          Restricted Global Note proposes to exchange such beneficial interest
          for a Restricted Definitive Note or to transfer such beneficial
          interest to a Person who takes delivery thereof in the form of a
          Restricted Definitive Note, then, upon receipt by the Registrar of the
          following documentation:

                    (A) if the holder of such beneficial interest in a
               Restricted Global Note proposes to exchange such beneficial
               interest for a Restricted Definitive Note, a certificate from
               such holder in the form of Exhibit C hereto, including the
               certifications in item (2)(a) thereof;

                    (B) if such beneficial interest is being transferred to a
               QIB in accordance with Rule 144A under the Securities Act, a
               certificate to the effect set forth in Exhibit B hereto,
               including the certifications in item (1) thereof;

                    (C) if such beneficial interest is being transferred to a
               Non-U.S. Person in an offshore transaction in accordance with
               Rule 903 or Rule 904 under the Securities Act, a certificate to
               the effect set forth in Exhibit B hereto, including the
               certifications in item (2) thereof;

                    (D) if such beneficial interest is being transferred
               pursuant to an exemption from the registration requirements of
               the Securities Act in accordance with Rule 144 under the
               Securities Act, a certificate to the effect set forth in Exhibit
               B hereto, including the certifications in item (3)(a) thereof;

                    (E) if such beneficial interest is being transferred to an
               Institutional Accredited Investor in reliance on an exemption
               from the registration requirements of the Securities Act other
               than those listed in subparagraphs (B) through (D) above, a
               certificate to the effect set forth in Exhibit B hereto,
               including the certifications, certificates and Opinion of Counsel
               required by item (3) thereof, if applicable;

                    (F) if such beneficial interest is being transferred to the
               Company or any of its Subsidiaries, a certificate to the effect
               set forth in Exhibit B hereto, including the certifications in
               item (3)(b) thereof; or

                    (G) if such beneficial interest is being transferred
               pursuant to an effective registration statement under the
               Securities Act, a certificate to the effect set forth in Exhibit
               B hereto, including the certifications in item (3)(c) thereof,

     the Trustee shall cause the aggregate principal amount of the applicable
     Global Note to be reduced accordingly pursuant to Section 2.06(h) hereof,
     and the Company shall execute and the Trustee shall authenticate and
     deliver to the Person designated in the instructions a Definitive Note in
     the appropriate principal amount. Any Definitive Note issued in exchange
     for a beneficial interest in a Restricted Global Note pursuant to this
     Section 2.06(c) shall be registered in such name or names and in such
     authorized denomination or denominations as the holder of such beneficial
     interest shall instruct the Registrar through instructions from the
     Depositary and the Participant or Indirect Participant. The Trustee shall
     deliver such Definitive Notes to the Persons in whose names such Notes are
     so registered. Any Definitive Note issued in exchange for a beneficial
     interest in a Restricted Global Note pursuant to this Section 2.06(c)(i)
     shall bear the Private Placement Legend and shall be subject to all
     restrictions on transfer contained therein.


<PAGE>
                                      -31-


          (ii) Beneficial Interests in Restricted Global Notes to Unrestricted
     Definitive Notes. A holder of a beneficial interest in a Restricted Global
     Note may exchange such beneficial interest for an Unrestricted Definitive
     Note or may transfer such beneficial interest to a Person who takes
     delivery thereof in the form of an Unrestricted Definitive Note only if:

               (A) such exchange or transfer is effected pursuant to the
          Exchange Offer in accordance with the Registration Rights Agreement
          and the holder of such beneficial interest, in the case of an
          exchange, or the transferee, in the case of a transfer, certifies in
          the applicable Letter of Transmittal that it is not (1) a
          broker-dealer, (2) a Person participating in the distribution of the
          Exchange Notes or (3) a Person who is an affiliate (as defined in Rule
          144) of the Company;

               (B) such transfer is effected pursuant to the Shelf Registration
          Statement in accordance with the Registration Rights Agreement;

               (C) such transfer is effected by a Broker-Dealer pursuant to the
          Exchange Offer Registration Statement in accordance with the
          Registration Rights Agreement; or

               (D) the Registrar receives the following:

                    (1) if the holder of such beneficial interest in a
               Restricted Global Note proposes to exchange such beneficial
               interest for a Definitive Note that does not bear the Private
               Placement Legend, a certificate from such holder in the form of
               Exhibit C hereto, including the certifications in item (1)(b)
               thereof; or

                    (2) if the holder of such beneficial interest in a
               Restricted Global Note proposes to transfer such beneficial
               interest to a Person who shall take delivery thereof in the form
               of a Definitive Note that does not bear the Private Placement
               Legend, a certificate from such holder in the form of Exhibit B
               hereto, including the certifications in item (4) thereof;

     and, in each such case set forth in this subparagraph (D), if the Registrar
     so requests or if the Applicable Procedures so require, an Opinion of
     Counsel in form reasonably acceptable to the Registrar to the effect that
     such exchange or transfer is in compliance with the Securities Act and that
     the restrictions on transfer contained herein and in the Private Placement
     Legend are no longer required in order to maintain compliance with the
     Securities Act.

          (iii) Beneficial Interests in Unrestricted Global Notes to
     Unrestricted Definitive Notes. If any holder of a beneficial interest in an
     Unrestricted Global Note proposes to exchange such beneficial interest for
     a Definitive Note or to transfer such beneficial interest to a Person who
     takes delivery thereof in the form of a Definitive Note, then, upon
     satisfaction of the conditions set forth in Section 2.06(b)(ii) hereof, the
     Trustee shall cause the aggregate principal amount of the applicable Global
     Note to be reduced accordingly pursuant to Section 2.06(h) hereof, and the
     Company shall execute and the Trustee shall authenticate and deliver to the
     Person designated in the instructions a Definitive Note in the appropriate
     principal amount. Any Definitive Note issued in exchange for a beneficial
     interest pursuant to this Section 2.06(c)(iii) shall be registered in such
     name or names and in such authorized denomination or denominations as the
     holder of such beneficial interest shall instruct the Registrar through
     instructions from the Depositary and the Participant or Indirect
     Participant. The Trustee shall deliver such Definitive Notes to the Persons
     in whose names such Notes are so registered. Any Definitive Note issued in
     exchange for a beneficial interest pursuant to this Section 2.06(c)(iii)
     shall not bear the Private Placement Legend.


<PAGE>
                                      -32-


     (d) Transfer and Exchange of Definitive Notes for Beneficial Interests in
Global Notes.

          (i) Restricted Definitive Notes to Beneficial Interests in Restricted
     Global Notes. If any Holder of a Restricted Definitive Note proposes to
     exchange such Note for a beneficial interest in a Restricted Global Note or
     to transfer such Restricted Definitive Notes to a Person who takes delivery
     thereof in the form of a beneficial interest in a Restricted Global Note,
     then, upon receipt by the Registrar of the following documentation:

               (A) if the Holder of such Restricted Definitive Note proposes to
          exchange such Note for a beneficial interest in a Restricted Global
          Note, a certificate from such Holder in the form of Exhibit C hereto,
          including the certifications in item (2)(b) thereof;

               (B) if such Restricted Definitive Note is being transferred to a
          QIB in accordance with Rule 144A under the Securities Act, a
          certificate to the effect set forth in Exhibit B hereto, including the
          certifications in item (1) thereof;

               (C) if such Restricted Definitive Note is being transferred to a
          Non-U.S. Person in an offshore transaction in accordance with Rule 903
          or Rule 904 under the Securities Act, a certificate to the effect set
          forth in Exhibit B hereto, including the certifications in item (2)
          thereof;

               (D) if such Restricted Definitive Note is being transferred
          pursuant to an exemption from the registration requirements of the
          Securities Act in accordance with Rule 144 under the Securities Act, a
          certificate to the effect set forth in Exhibit B hereto, including the
          certifications in item (3)(a) thereof;

               (E) if such Restricted Definitive Note is being transferred to an
          Institutional Accredited Investor in reliance on an exemption from the
          registration requirements of the Securities Act other than those
          listed in subparagraphs (B) through (D) above, a certificate to the
          effect set forth in Exhibit B hereto, including the certifications,
          certificates and Opinion of Counsel required by item (3) thereof, if
          applicable;

               (F) if such Restricted Definitive Note is being transferred to
          the Company or any of its Subsidiaries, a certificate to the effect
          set forth in Exhibit B hereto, including the certifications in item
          (3)(b) thereof; or

               (G) if such Restricted Definitive Note is being transferred
          pursuant to an effective registration statement under the Securities
          Act, a certificate to the effect set forth in Exhibit B hereto,
          including the certifications in item (3)(c) thereof,

     the Trustee shall cancel the Restricted Definitive Note, increase or cause
     to be increased the aggregate principal amount of, in the case of clause
     (A) above, the appropriate Restricted Global Note, in the case of clause
     (B) above, the 144A Global Note, in the case of clause (C) above, the
     Regulation S Global Note.

          (ii) Restricted Definitive Notes to Beneficial Interests in
     Unrestricted Global Notes. A Holder of a Restricted Definitive Note may
     exchange such Note for a beneficial interest in an Unrestricted Global Note
     or transfer such Restricted Definitive Note to a Person who takes delivery
     thereof in the form of a beneficial interest in an Unrestricted Global Note
     only if:


<PAGE>
                                      -33-


               (A) such exchange or transfer is effected pursuant to the
          Exchange Offer in accordance with the Registration Rights Agreement
          and the Holder, in the case of an exchange, or the transferee, in the
          case of a transfer, certifies in the applicable Letter of Transmittal
          that it is not (1) a broker-dealer, (2) a Person participating in the
          distribution of the Exchange Notes or (3) a Person who is an affiliate
          (as defined in Rule 144) of the Company;

               (B) such transfer is effected pursuant to the Shelf Registration
          Statement in accordance with the Registration Rights Agreement;

               (C) such transfer is effected by a Broker-Dealer pursuant to the
          Exchange Offer Registration Statement in accordance with the
          Registration Rights Agreement; or

               (D) the Registrar receives the following:

                    (1) if the Holder of such Definitive Notes proposes to
               exchange such Notes for a beneficial interest in the Unrestricted
               Global Note, a certificate from such Holder in the form of
               Exhibit C hereto, including the certifications in item (1)(c)
               thereof; or

                    (2) if the Holder of such Definitive Notes proposes to
               transfer such Notes to a Person who shall take delivery thereof
               in the form of a beneficial interest in the Unrestricted Global
               Note, a certificate from such Holder in the form of Exhibit B
               hereto, including the certifications in item (4) thereof;

     and, in each such case set forth in this subparagraph (D), if the Registrar
     so requests or if the Applicable Procedures so require, an Opinion of
     Counsel in form reasonably acceptable to the Registrar to the effect that
     such exchange or transfer is in compliance with the Securities Act and that
     the restrictions on transfer contained herein and in the Private Placement
     Legend are no longer required in order to maintain compliance with the
     Securities Act.

     Upon satisfaction of the conditions of any of the subparagraphs in this
     Section 2.06(d)(ii), the Trustee shall cancel the Definitive Notes and
     increase or cause to be increased the aggregate principal amount of the
     Unrestricted Global Note.

          (iii) Unrestricted Definitive Notes to Beneficial Interests in
     Unrestricted Global Notes. A Holder of an Unrestricted Definitive Note may
     exchange such Note for a beneficial interest in an Unrestricted Global Note
     or transfer such Definitive Notes to a Person who takes delivery thereof in
     the form of a beneficial interest in an Unrestricted Global Note at any
     time. Upon receipt of a request for such an exchange or transfer, the
     Trustee shall cancel the applicable Unrestricted Definitive Note and
     increase or cause to be increased the aggregate principal amount of one of
     the Unrestricted Global Notes.

     If any such exchange or transfer from a Definitive Note to a beneficial
     interest is effected pursuant to subparagraphs (ii)(B), (ii)(D) or (iii)
     above at a time when an Unrestricted Global Note has not yet been issued,
     the Company shall issue and, upon receipt of an Authentication Order in
     accordance with Section 2.02 hereof, the Trustee shall authenticate one or
     more Unrestricted Global Notes in an aggregate principal amount equal to
     the principal amount of Definitive Notes so transferred.

     (e) Transfer and Exchange of Definitive Notes for Definitive Notes. Upon
request by a Holder of Definitive Notes and such Holder's compliance with the
provisions of this Section 2.06(e), the Registrar shall register the transfer or
exchange of Definitive Notes. Prior to such registration of transfer or
exchange, the re-


<PAGE>
                                      -34-


questing Holder shall present or surrender to the Registrar the Definitive Notes
duly endorsed or accompanied by a written instruction of transfer in form
satisfactory to the Registrar duly executed by such Holder or by its attorney,
duly authorized in writing. In addition, the requesting Holder shall provide any
additional certifications, documents and information, as applicable, required
pursuant to the following provisions of this Section 2.06(e).

          (i) Restricted Definitive Notes to Restricted Definitive Notes. Any
     Restricted Definitive Note may be transferred to and registered in the name
     of Persons who take delivery thereof in the form of a Restricted Definitive
     Note if the Registrar receives the following:

               (A) if the transfer will be made pursuant to Rule 144A under the
          Securities Act, then the transferor must deliver a certificate in the
          form of Exhibit B hereto, including the certifications in item (1)
          thereof;

               (B) if the transfer will be made pursuant to Rule 903 or Rule
          904, then the transferor must deliver a certificate in the form of
          Exhibit B hereto, including the certifications in item (2) thereof;
          and

               (C) if the transfer will be made pursuant to any other exemption
          from the registration requirements of the Securities Act, then the
          transferor must deliver a certificate in the form of Exhibit B hereto,
          including the certifications, certificates and Opinion of Counsel
          required by item (3) thereof, if applicable.

          (ii) Restricted Definitive Notes to Unrestricted Definitive Notes. Any
     Restricted Definitive Note may be exchanged by the Holder thereof for an
     Unrestricted Definitive Note or transferred to a Person or Persons who take
     delivery thereof in the form of an Unrestricted Definitive Note if:

               (A) such exchange or transfer is effected pursuant to the
          Exchange Offer in accordance with the Registration Rights Agreement
          and the Holder, in the case of an exchange, or the transferee, in the
          case of a transfer, certifies in the applicable Letter of Transmittal
          that it is not (1) a broker-dealer, (2) a Person participating in the
          distribution of the Exchange Notes or (3) a Person who is an affiliate
          (as defined in Rule 144) of the Company;

               (B) any such transfer is effected pursuant to the Shelf
          Registration Statement in accordance with the Registration Rights
          Agreement;

               (C) any such transfer is effected by a Broker-Dealer pursuant to
          the Exchange Offer Registration Statement in accordance with the
          Registration Rights Agreement; or

               (D) the Registrar receives the following:

                    (1) if the Holder of such Restricted Definitive Notes
               proposes to exchange such Notes for an Unrestricted Definitive
               Note, a certificate from such Holder in the form of Exhibit C
               hereto, including the certifications in item (1)(d) thereof; or

                    (2) if the Holder of such Restricted Definitive Notes
               proposes to transfer such Notes to a Person who shall take
               delivery thereof in the form of an Unrestricted Definitive Note,
               a certificate from such Holder in the form of Exhibit B hereto,
               including the certifications in item (4) thereof;


<PAGE>
                                      -35-


     and, in each such case set forth in this subparagraph (D), if the Registrar
     so requests, an Opinion of Counsel in form reasonably acceptable to the
     Company to the effect that such exchange or transfer is in compliance with
     the Securities Act and that the restrictions on transfer contained herein
     and in the Private Placement Legend are no longer required in order to
     maintain compliance with the Securities Act.

          (iii) Unrestricted Definitive Notes to Unrestricted Definitive Notes.
     A Holder of Unrestricted Definitive Notes may transfer such Notes to a
     Person who takes delivery thereof in the form of an Unrestricted Definitive
     Note. Upon receipt of a request to register such a transfer, the Registrar
     shall register the Unrestricted Definitive Notes pursuant to the
     instructions from the Holder thereof.

     (f) Exchange Offer. Upon the occurrence of an Exchange Offer in accordance
with the Registration Rights Agreement, the Company shall issue and, upon
receipt of an Authentication Order in accordance with Section 2.02, the Trustee
shall authenticate (i) one or more Unrestricted Global Notes in an aggregate
principal amount equal to the principal amount of the beneficial interests in
the Restricted Global Notes tendered for acceptance by Persons that certify in
the applicable Letters of Transmittal that (x) they are not broker-dealers, (y)
they are not participating in a distribution of the Exchange Notes and (z) they
are not affiliates (as defined in Rule 144) of the Company, and accepted for
exchange in the Exchange Offer and (ii) Definitive Notes in an aggregate
principal amount equal to the principal amount of the Restricted Definitive
Notes accepted for exchange in the Exchange Offer. Concurrently with the
issuance of such Notes, the Trustee shall cause the aggregate principal amount
of the applicable Restricted Global Notes to be reduced accordingly, and the
Company shall execute and the Trustee shall authenticate and deliver to the
Persons designated by the Holders of Definitive Notes so accepted Definitive
Notes in the appropriate principal amount.

     (g) Legends. The following legends shall appear on the face of all Global
Notes and Definitive Notes issued under this Indenture unless specifically
stated otherwise in the applicable provisions of this Indenture.

          (i) Private Placement Legend.

                    (A) Except as permitted by subparagraph (B) below, each
               Global Note and each Definitive Note (and all Notes issued in
               exchange therefor or substitution thereof) shall bear the legend
               in substantially the following form:

               "THIS NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED UNDER THE
               U.S. SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT")
               AND, ACCORDINGLY, MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE
               TRANSFERRED WITHIN THE UNITED STATES OR TO, OR FOR THE ACCOUNT OR
               BENEFIT OF, U.S. PERSONS, EXCEPT AS SET FORTH IN THE NEXT
               SENTENCE. BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL INTEREST
               HEREIN, THE HOLDER: (1) REPRESENTS THAT (A) IT IS A "QUALIFIED
               INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A UNDER THE
               SECURITIES ACT) (A "QIB"), (B) IT HAS ACQUIRED THIS NOTE IN AN
               OFFSHORE TRANSACTION IN COMPLIANCE WITH REGULATION S UNDER THE
               SECURITIES ACT OR (C) 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 "IAI"), (2) AGREES
               THAT IT WILL NOT RESELL OR OTHERWISE TRANSFER THE NOTE EXCEPT (A)
               TO THE COMPANY OR ANY OF ITS SUBSIDIARIES, (B) TO A PERSON WHOM
               THE SELLER REASONABLY BELIEVES IS A QIB PURCHASING FOR ITS OWN
               ACCOUNT OR FOR THE ACCOUNT OF A QIB IN A TRANSACTION MEETING THE
               REQUIREMENTS OF RULE 144A, (C) IN


<PAGE>
                                      -36-


               AN OFFSHORE TRANSACTION MEETING THE REQUIREMENTS OF RULE 903 OR
               904 OF THE SECURITIES ACT, (D) IN A TRANSACTION MEETING THE
               REQUIREMENTS OF RULE 144 UNDER THE SECURITIES ACT, (E) TO AN IAI
               THAT, PRIOR TO SUCH TRANSFER, FURNISHES THE TRUSTEE A SIGNED
               LETTER CONTAINING CERTAIN REPRESENTATIONS AND AGREEMENTS RELATING
               TO THE TRANSFER OF THIS NOTE (THE FORM OF WHICH CAN BE OBTAINED
               FROM THE TRUSTEE) AND , IF SUCH TRANSFER IS IN RESPECT OF AN
               AGGREGATE PRINCIPAL AMOUNT OF NOTES LESS THAN $250,000, AN
               OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH TRANSFER
               IS IN COMPLIANCE WITH THE SECURITIES ACT, (F) IN ACCORDANCE WITH
               ANOTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE
               SECURITIES ACT (AND BASED UPON AN OPINION OF COUNSEL ACCEPTABLE
               TO THE COMPANY) OR (G) PURSUANT TO AN EFFECTIVE REGISTRATION
               STATEMENT AND, IN EACH CASE, IN ACCORDANCE WITH OTHER APPLICABLE
               SECURITIES LAWS OF ANY STATE OF THE UNITED STATES OR ANY OTHER
               APPLICABLE JURISDICTION AND (3) AGREES THAT IT WILL DELIVER TO
               EACH PERSON TO WHOM THIS NOTE OR AN INTEREST HEREIN IS
               TRANSFERRED A NOTICE SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND.
               AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION" AND "UNITED
               STATES" HAVE THE MEANINGS GIVEN TO THEM BY RULE 902 OF 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."

                    (B) Notwithstanding the foregoing, any Global Note or
               Definitive Note issued pursuant to subparagraphs (b)(iv),
               (c)(ii), (c)(iii), (d)(ii), (d)(iii), (e)(ii), (e)(iii) or (f) to
               this Section 2.06 (and all Notes issued in exchange therefor or
               substitution thereof) shall not bear the Private Placement
               Legend.

          (ii) Global Note Legend. Each Global Note shall bear a legend in
     substantially the following form:

     "THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE
     GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE
     BENEFICIAL OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY
     CIRCUMSTANCES EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS
     MAY BE REQUIRED PURSUANT TO SECTION 2.07 OF THE INDENTURE, (II) THIS GLOBAL
     NOTE MAY BE EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.06(a)
     OF THE INDENTURE, (III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE
     FOR CANCELLATION PURSUANT TO SECTION 2.11 OF THE INDENTURE."

     (h) Cancellation and/or Adjustment of Global Notes. At such time as all
beneficial interests in a particular Global Note have been exchanged for
Definitive Notes or a particular Global Note has been redeemed, repurchased or
canceled in whole and not in part, each such Global Note shall be returned to or
retained and canceled by the Trustee in accordance with Section 2.11 hereof. At
any time prior to such cancellation, if any beneficial interest in a Global Note
is exchanged for or transferred to a Person who will take delivery thereof in
the form of a benefi-


<PAGE>
                                      -37-


cial interest in another Global Note or for Definitive Notes, the principal
amount of Notes represented by such Global Note shall be reduced accordingly and
an endorsement shall be made on such Global Note by the Trustee or by the
Depositary at the direction of the Trustee to reflect such reduction; and if the
beneficial interest is being exchanged for or transferred to a Person who will
take delivery thereof in the form of a beneficial interest in another Global
Note, such other Global Note shall be increased accordingly and an endorsement
shall be made on such Global Note by the Trustee or by the Depositary at the
direction of the Trustee to reflect such increase.

     (i) General Provisions Relating to Transfers and Exchanges.

          (i) To permit registrations of transfers and exchanges, the Company
     shall execute and the Trustee shall authenticate Global Notes and
     Definitive Notes upon the Company's order or at the Registrar's request.

          (ii) No service charge shall be made to a holder of a beneficial
     interest in a Global Note or to a Holder of a Definitive Note for any
     registration of transfer or exchange, but the Company may require payment
     of a sum sufficient to cover any transfer tax or similar governmental
     charge payable in connection therewith (other than any such transfer taxes
     or similar governmental charge payable upon exchange or transfer pursuant
     to Sections 2.10, 3.06, 3.09, 4.10, 4.14 and 9.05 hereof).

          (iii) The Registrar shall not be required to register the transfer of
     or exchange any Note selected for redemption in whole or in part, except
     the unredeemed portion of any Note being redeemed in part.

          (iv) All Global Notes and Definitive Notes issued upon any
     registration of transfer or exchange of Global Notes or Definitive Notes
     shall be the valid obligations of the Company, evidencing the same debt,
     and entitled to the same benefits under this Indenture, as the Global Notes
     or Definitive Notes surrendered upon such registration of transfer or
     exchange.

          (v) The Company shall not be required (A) to issue, to register the
     transfer of or to exchange any Notes during a period beginning at the
     opening of business 15 days before the day of any selection of Notes for
     redemption under Section 3.02 hereof and ending at the close of business on
     the day of selection, (B) to register the transfer of or to exchange any
     Note so selected for redemption in whole or in part, except the unredeemed
     portion of any Note being redeemed in part or (C) to register the transfer
     of or to exchange a Note between a record date and the next succeeding
     Interest Payment Date.

          (vi) Prior to due presentment for the registration of a transfer of
     any Note, the Trustee, any Agent and the Company may deem and treat the
     Person in whose name any Note is registered as the absolute owner of such
     Note for the purpose of receiving payment of principal of and interest on
     such Notes and for all other purposes, and none of the Trustee, any Agent
     or the Company shall be affected by notice to the contrary.

          (vii) The Trustee shall authenticate Global Notes and Definitive Notes
     in accordance with the provisions of Section 2.02 hereof.

          (viii) All certifications, certificates and Opinions of Counsel
     required to be submitted to the Registrar pursuant to this Section 2.06 to
     effect a registration of transfer or exchange may be submitted by
     facsimile.


<PAGE>
                                      -38-


Section 2.07.     Replacement Notes.

     If any mutilated Note is surrendered to the Trustee or the Company and the
Trustee receives evidence to its satisfaction of the destruction, loss or theft
of any Note, the Company shall issue and the Trustee, upon receipt of an
Authentication Order, shall authenticate a replacement Note if the Trustee's
requirements are met. If required by the Trustee or the Company, an indemnity
bond must be supplied by the Holder that is sufficient in the judgment of the
Trustee and the Company to protect the Company, the Trustee, any Agent and any
authenticating agent from any loss that any of them may suffer if a Note is
replaced. The Company may charge for its expenses in replacing a Note.

     Every replacement Note is an obligation of the Company issued as evidence
of the same underlying indebtedness as the replaced Note and shall be entitled
to all of the benefits of this Indenture equally and proportionately with all
other Notes duly issued hereunder.

Section 2.08.     Outstanding Notes.

     The Notes outstanding at any time are all the Notes authenticated by the
Trustee except for those canceled by it, those delivered to it for cancellation,
those reductions in the interest in a Global Note effected by the Trustee in
accordance with the provisions hereof, and those described in this Section as
not outstanding. Except as set forth in Section 2.09 hereof, a Note does not
cease to be outstanding because the Company or an Affiliate of the Company holds
the Note; however, Notes held by the Company or a Subsidiary of the Company
shall not be deemed to be outstanding for purposes of Section 3.07(b) hereof.

     If a Note is replaced pursuant to Section 2.07 hereof, it ceases to be
outstanding unless the Trustee receives proof satisfactory to it that the
replaced Note is held by a protected purchaser.

     If the principal amount of any Note is considered paid under Section 4.01
hereof, it ceases to be outstanding and interest on it ceases to accrue.

     If the Paying Agent (other than the Company, a Subsidiary or an Affiliate
of any thereof) holds, on a redemption date or maturity date, money sufficient
to pay Notes payable on that date, then on and after that date such Notes shall
be deemed to be no longer outstanding and shall cease to accrue interest.

Section 2.09.     Treasury Notes.

     In determining whether the Holders of the required principal amount of
Notes have concurred in any direction, waiver or consent, Notes owned by the
Company, or by any Person directly or indirectly controlling or controlled by or
under direct or indirect common control with the Company, shall be considered as
though not outstanding, except that for the purposes of determining whether the
Trustee shall be protected in relying on any such direction, waiver or consent,
only Notes that a Responsible Officer of the Trustee knows are so owned shall be
so disregarded.

Section 2.10.     Temporary Notes.

     Until certificates representing Notes are ready for delivery, the Company
may prepare and the Trustee, upon receipt of an Authentication Order, shall
authenticate temporary Notes. Temporary Notes shall be substantially in the form
of certificated Notes but may have variations that the Company considers
appropriate for temporary Notes and as shall be reasonably acceptable to the
Trustee. Without unreasonable delay, the Company shall prepare and the Trustee
shall authenticate definitive Notes in exchange for temporary Notes.


<PAGE>
                                      -39-


     Holders of temporary Notes shall be entitled to all of the benefits of this
Indenture.

Section 2.11.     Cancellation.

     The Company at any time may deliver Notes to the Trustee for cancellation.
The Registrar and Paying Agent shall forward to the Trustee any Notes
surrendered to them for registration of transfer, exchange or payment. The
Trustee and no one else shall cancel all Notes surrendered for registration of
transfer, exchange, payment, replacement or cancellation and shall destroy
canceled Notes in accordance with its customary procedures. The Company may not
issue new Notes to replace Notes that it has paid or that have been delivered to
the Trustee for cancellation.

Section 2.12.     Defaulted Interest.

     If the Company defaults in a payment of interest on any Notes, it shall pay
the defaulted interest in any lawful manner plus, to the extent lawful, interest
payable on the defaulted interest, to the Persons who are Holders on a
subsequent special record date, in each case at the applicable rate provided in
such Notes and in Section 4.01 hereof. The Company shall notify the Trustee in
writing of the amount of defaulted interest proposed to be paid on each Note and
the date of the proposed payment. The Company shall fix or cause to be fixed
each such special record date and payment date, provided that no such special
record date shall be less than 10 days prior to the related payment date for
such defaulted interest. At least 15 days before the special record date, the
Company (or, upon the written request of the Company, the Trustee in the name
and at the expense of the Company) shall mail or cause to be mailed to Holders a
notice that states the special record date, the related payment date and the
amount of such interest to be paid.

                                    ARTICLE 3
                            REDEMPTION AND PREPAYMENT

Section 3.01.     Notices to Trustee.

     If the Company elects to redeem Notes pursuant to the optional redemption
provisions of Section 3.07 hereof, it shall furnish to the Trustee, at least 30
days but not more than 60 days before a redemption date, an Officers'
Certificate setting forth (i) the clause of this Indenture pursuant to which the
redemption shall occur, (ii) the redemption date, (iii) the principal amount of
Notes to be redeemed and (iv) the redemption price.

Section 3.02.     Selection of Notes to Be Redeemed.

     If less than all of the Notes are to be redeemed or purchased in an offer
to purchase at any time, the Trustee shall select the Notes to be redeemed or
purchased among the Holders of such Notes on a pro rata basis.

     The Trustee shall promptly notify the Company in writing of the Notes
selected for redemption and, in the case of any Note selected for partial
redemption, the principal amount thereof to be redeemed. Notes and portions of
Notes selected shall be in amounts of $1,000 or whole multiples of $1,000;
except that if all of the Notes of a Holder are to be redeemed, the entire
outstanding amount of Notes held by such Holder, even if not a multiple of
$1,000, shall be redeemed. Except as provided in the preceding sentence,
provisions of this Indenture that apply to Notes called for redemption also
apply to portions of Notes called for redemption.


<PAGE>
                                      -40-


Section 3.03.     Notice of Redemption.

     Subject to the provisions of Section 3.09 hereof, at least 30 days but not
more than 60 days before a redemption date, the Company shall mail or cause to
be mailed, by first class mail, a notice of redemption to each Holder whose
Notes are to be redeemed at its registered address.

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

          (a) the redemption date;

          (b) the redemption price;

          (c) if any Note is being redeemed in part, the portion of the
     principal amount of such Note to be redeemed and that, after the redemption
     date upon surrender of such Note, a new Note or Notes in principal amount
     equal to the unredeemed portion shall be issued upon cancellation of the
     original Note;

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

          (e) that Notes called for redemption must be surrendered to the Paying
     Agent to collect the redemption price;

          (f) that, unless the Company defaults in making such redemption
     payment, interest on Notes called for redemption ceases to accrue on and
     after the redemption date;

          (g) the paragraph of the Notes and/or Section of this Indenture
     pursuant to which the Notes called for redemption are being redeemed; and

          (h) that no representation is made as to the correctness or accuracy
     of the CUSIP number, if any, listed in such notice or printed on the Notes.

     At the Company's request, the Trustee shall give the notice of redemption
in the Company's name and at its expense; provided, however, that the Company
shall have delivered to the Trustee, at least 45 days prior to the redemption
date, an Officers' Certificate requesting that the Trustee give such notice and
setting forth the information to be stated in such notice as provided in the
preceding paragraph.

Section 3.04.     Effect of Notice of Redemption.

     Once notice of redemption is mailed in accordance with Section 3.03 hereof,
Notes called for redemption become irrevocably due and payable on the redemption
date at the redemption price. A notice of redemption may not be conditional.

Section 3.05.     Deposit of Redemption Price.

     At or prior to 10:00 a.m., New York City time, on the redemption date, the
Company shall deposit with the Trustee or with the Paying Agent money sufficient
to pay the redemption price of and accrued interest on all Notes to be redeemed
on that date. The Trustee or the Paying Agent shall promptly return to the
Company any money deposited with the Trustee or the Paying Agent by the Company
in excess of the amounts necessary to pay the redemption price of, and accrued
interest on, all Notes to be redeemed.


<PAGE>
                                      -41-


     If the Company complies with the provisions of the preceding paragraph, on
and after the redemption date, interest shall cease to accrue on the Notes or
the portions of Notes called for redemption. If a Note is redeemed on or after
an interest record date but on or prior to the related interest payment date,
then any accrued and unpaid interest shall be paid to the Person in whose name
such Note was registered at the close of business on such record date. If any
Note called for redemption shall not be so paid upon surrender for redemption
because of the failure of the Company to comply with the preceding paragraph,
interest shall be paid on the unpaid principal, from the redemption date until
such principal is paid, and to the extent lawful on any interest not paid on
such unpaid principal, in each case at the rate provided in the Notes and in
Section 4.01 hereof.

Section 3.06.     Notes Redeemed in Part.

     Upon surrender of a Note that is redeemed in part, the Company shall issue
and, upon the Company's written request, the Trustee shall authenticate for the
Holder at the expense of the Company a new Note equal in principal amount to the
unredeemed portion of the Note surrendered.

Section 3.07.     Optional Redemption.

     (a) Except as set forth in this Section 3.07, the Company shall not have
the option to redeem the Notes.

     (b) The Company may redeem the Notes in the event the Company becomes
obligated to pay any Additional Amounts as a result of a change in the laws or
regulations of Canada or any Canadian Taxing Authority, or a change in any
official position regarding the application or interpretation thereof, which is
publicly announced or becomes effective on or after the Issue Date. Upon the
occurrence of any such change, the Company may, at any time, redeem, subject to
the provisions of the immediately succeeding paragraph, all, but not part, of
the Notes at a price equal to 100% of the principal amount thereof, plus accrued
and unpaid interest, if any, to the redemption date.

     At any time that the aggregate principal amount of Notes outstanding is
greater than $100.0 million, any Holder of Notes may by delivering a notice (the
"Waiver Notice") to the Company within ten days of the mailing of the Notice F
Redemption, to the extent that it does not adversely affect the Company's
after-tax position, as determined within 10 days of receipt by the Company of
the Waiver Notice, at its option, waive the Company's compliance with the
provisions of Section 4.05; provided that if any Holder waives such compliance,
Company may not redeem that Holder's Notes pursuant to this Section 3.07.

     (c) Any redemption pursuant to this Section 3.07 shall be made pursuant to
the provisions of Section 3.01 through 3.06 hereof.

Section 3.08.     Mandatory Redemption.

     Except as otherwise provided in Section 4.10 or Section 4.14 below, the
Company shall not be required to make mandatory redemption payments with respect
to the Notes.

Section 3.09.     Offer to Purchase by Application of Excess Proceeds.

     In the event that the Company shall be required to commence an offer to all
Holders to purchase Notes and pari passu Indebtedness, including the Euro Notes,
pursuant to Section 4.10 hereof (an "Asset Sale Offer"), it shall follow the
procedures specified below.


<PAGE>
                                      -42-


     The Asset Sale Offer shall remain open for a period of 20 Business Days
following its commencement and no longer, except to the extent that a longer
period is required by applicable law (the "Offer Period"). No later than five
Business Days after the termination of the Offer Period (the "Purchase Date"),
the Company shall purchase the principal amount of Notes and pari passu
Indebtedness, including the Euro Notes, required to be purchased pursuant to
Section 4.10 hereof (the "Offer Amount") or, if less than the Offer Amount has
been tendered, all Notes and pari passu Indebtedness tendered in response to the
Asset Sale Offer. Payment for any Notes so purchased shall be made in the same
manner as interest payments are made.

     If the Purchase Date is on or after an interest record date and on or
before the related interest payment date, any accrued and unpaid interest shall
be paid to the Person in whose name a Note is registered at the close of
business on such record date, and no additional interest shall be payable to
Holders who tender Notes pursuant to the Asset Sale Offer.

     Upon the commencement of an Asset Sale Offer the Company shall send, by
first class mail, a notice to the Trustee and each of the Holders, with a copy
to the Trustee. The notice shall contain all instructions and materials
necessary to enable such Holders to tender Notes pursuant to the Asset Sale
Offer. The Asset Sale Offer shall be made to all Holders. The notice, which
shall govern the terms of the Asset Sale Offer shall state:

          (a) that the Asset Sale Offer is being made pursuant to this Section
     3.09 and Section 4.10 hereof and the length of time the Asset Sale Offer
     shall remain open;

          (b) the Offer Amount, the purchase price and the Purchase Date;

          (c) that any Note not tendered or accepted for payment shall continue
     to accrue interest;

          (d) that, unless the Company defaults in making such payment, any Note
     accepted for payment pursuant the Asset Sale Offer shall cease to accrue
     interest after the Purchase Date;

          (e) that Holders electing to have a Note purchased pursuant to an
     Asset Sale Offer may elect to have Notes purchased in integral multiples of
     $1,000 only;

          (f) that Holders electing to have a Note purchased pursuant to any
     Asset Sale Offer shall be required to surrender the Note, with the form
     entitled "Option of Holder to Elect Purchase" on the reverse of the Note
     completed, or transfer by book-entry transfer, to the Company, a
     depositary, if appointed by the Company, or a Paying Agent at the address
     specified in the notice at least three days before the Purchase Date;

          (g) that Holders shall be entitled to withdraw their election if the
     Company, the depositary or the Paying Agent, as the case may be, receives,
     not later than the expiration of the Offer Period, a telegram, telex,
     facsimile transmission or letter setting forth the name of the Holder, the
     principal amount of the Note the Holder delivered for purchase and a
     statement that such Holder is withdrawing his election to have such Note
     purchased;

          (h) that, if the aggregate principal amount of Notes surrendered by
     Holders exceeds the Offer Amount, the Company shall select the Notes and
     pari passu Indebtedness, including the Euro Notes, to be purchased on a pro
     rata basis (with such adjustments as may be deemed appropriate by the
     Company so that only Notes in denominations of $1,000, or integral
     multiples thereof, shall be purchased); and


<PAGE>
                                      -43-


          (i) that Holders whose Notes were purchased only in part shall be
     issued new Notes equal in principal amount to the unpurchased portion of
     the Notes surrendered (or transferred by book-entry transfer).

     On or before the Purchase Date, the Company shall, to the extent lawful,
accept for payment, on a pro rata basis to the extent necessary, the Offer
Amount of Notes and pari passu Indebtedness, including the Euro Notes, or
portions thereof tendered pursuant to the Asset Sale Offer or if less than the
Offer Amount has been tendered, all Notes and such pari passu Indebtedness
tendered, and shall deliver to the Trustee an Officers' Certificate stating that
such Notes or portions thereof were accepted for payment by the Company in
accordance with the terms of this Section 3.09. The Company, the Depositary or
the Paying Agent, as the case may be, shall promptly (but in any case not later
than five days after the Purchase Date) mail or deliver to each tendering Holder
an amount equal to the purchase price of the Notes tendered by such Holder and
accepted by the Company for purchase, and the Company shall promptly issue a new
Note, and the Trustee, upon written request from the Company shall authenticate
and mail or deliver such new Note to such Holder, in a principal amount equal to
any unpurchased portion of the Note surrendered. Any Note not so accepted shall
be promptly mailed or delivered by the Company to the Holder thereof. The
Company shall publicly announce the results of the Asset Sale Offer on the
Purchase Date.

     Other than as specifically provided in this Section 3.09, any purchase
pursuant to this Section 3.09 shall be made pursuant to the provisions of
Sections 3.01 through 3.06 hereof.

                                    ARTICLE 4
                                    COVENANTS

Section 4.01.     Payment of Notes.

     The Company shall pay or cause to be paid the principal of, premium, if
any, and interest on the Notes on the dates and in the manner provided in the
Notes. Principal, premium, if any, and interest shall be considered paid on the
date due if the Paying Agent, if other than the Company or a Subsidiary thereof,
holds as of 10:00 a.m. New York City time on the due date money deposited by the
Company in immediately available funds and designated for and sufficient to pay
all principal, premium, if any, and interest then due. The Company shall pay all
Additional Interest, if any, in the same manner on the dates and in the amounts
set forth in the Registration Rights Agreement. Whenever in this Indenture there
is mentioned, in any context, the payment of principal, premium, if any,
redemption price, Change of Control Payment, offer price and interest, or any
other amount payable under or with respect to any Note, such mention shall be
deemed to include mention of the payment of Additional Amounts to the extent
that, in such context, Additional Amounts are, were or would be payable in
respect thereof.

     The Company shall pay interest (including post-petition interest in any
proceeding under any Bankruptcy Law) on overdue principal at the rate equal to
1% per annum in excess of the then applicable interest rate on the Notes to the
extent lawful; it shall pay interest (including post-petition interest in any
proceeding under any Bankruptcy Law) on overdue installments of interest
(without regard to any applicable grace period) at the same rate to the extent
lawful.

Section 4.02.     Maintenance of Office or Agency.

     The Company shall maintain in the Borough of Manhattan, the City of New
York, an office or agency (which may be an office of the Trustee or an affiliate
of the Trustee, Registrar or co-registrar) where Notes may be surrendered for
registration of transfer or for exchange and where notices and demands to or
upon the Com-


<PAGE>
                                      -44-


pany in respect of the Notes and this Indenture may be served. The Company shall
give prompt written notice to the Trustee of the location, and any change in the
location, of such office or agency. If at any time the Company shall fail to
maintain any such required office or agency or shall fail to furnish the Trustee
with the address thereof, such presentations, surrenders, notices and demands
may be made or served at the Corporate Trust Office of the Trustee.

     The Company may also from time to time designate one or more other offices
or agencies where the Notes may be presented or surrendered for any or all such
purposes and may from time to time rescind such designations; provided, however,
that no such designation or rescission shall in any manner relieve the Company
of its obligation to maintain an office or agency in the Borough of Manhattan,
the City of New York for such purposes. The Company shall 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 designates the Corporate Trust Office of the Trustee as
one such office or agency of the Company in accordance with Section 2.03.

Section 4.03.     Reports.

     Whether or not required by the rules and regulations of the SEC, for so
long as any Notes remain outstanding, the Company shall furnish to the Holders
the information required to be delivered pursuant to Rule 144A(d)(4) under the
Securities Act. Whether or not the Company is subject to Section 13(a) or 15(d)
of the Exchange Act, the Company shall file with the SEC and furnish to the
Holders and the Trustee (i) within 140 days after the end of each fiscal year,
annual reports on Form 20-F or 40-F, as applicable (or any successor form),
containing the information required to be contained therein (or required in such
successor form) and (ii) (a) within 45 days after the end of each of the first
three fiscal quarters of each fiscal year, reports on Form 10-Q or (b) within 60
days after the end of each of the first three fiscal quarters of each fiscal
year, reports on Form 6-K (or any successor form) which, regardless of
applicable requirements, shall, at a minimum, contain a "Management's Discussion
and Analysis of Financial Condition and Results of Operations."

Section 4.04.     Compliance Certificate.

     (a) The Company shall deliver to the Trustee, within 90 days after the end
of each fiscal year, an Officers' Certificate stating that a review of the
activities of the Company and its Subsidiaries during the preceding fiscal year
has been made under the supervision of the signing Officers with a view to
determining whether the Company has kept, observed, performed and fulfilled its
obligations under this Indenture, and further stating, as to each such Officer
signing such certificate, that to the best of his or her knowledge the Company
has kept, observed, performed and fulfilled each and every covenant contained in
this Indenture, including without limitation the obligations set forth in
Section 4.07, and is not in default in the performance or observance of any of
the terms, provisions and conditions of this Indenture (or, if a Default or
Event of Default shall have occurred, describing all such Defaults or Events of
Default of which he or she may have knowledge and what action the Company is
taking or proposes to take with respect thereto) and that to the best of his or
her knowledge no event has occurred and remains in existence by reason of which
payments on account of the principal of or interest, if any, on the Notes is
prohibited or if such event has occurred, a description of the event and what
action the Company is taking or proposes to take with respect thereto.

     (b) So long as not contrary to the then current recommendations of the
American Institute of Certified Public Accountants, the year-end financial
statements delivered pursuant to Section 4.03(a) above shall be accompanied by a
written statement of the Company's independent public accountants (who shall be
a firm of established national reputation) that in making the examination
necessary for certification of such financial


<PAGE>
                                      -45-


statements, nothing has come to their attention that would lead them to believe
that the Company has violated any provisions of Article 4 or Article 5 hereof
or, if any such violation has occurred, specifying the nature and period of
existence thereof, it being understood that such accountants shall not be liable
directly or indirectly to any Person for any failure to obtain knowledge of any
such violation. In the event that, after the Company has used its reasonable
best efforts to obtain the written statement of the Company's independent public
accountants required by the provisions of this paragraph, such statement cannot
be obtained, the Company shall deliver, in satisfaction of its obligations under
this Section 4.04, an Officers' Certificate (A) certifying that it has used its
reasonable best efforts to obtain such required statement but was unable to do
so and (B) attaching the written statement of the Company's accountants that the
Company received in lieu thereof.

     (c) The Company shall, so long as any of the Notes are outstanding, deliver
to the Trustee, forthwith upon any Officer becoming aware of any Default or
Event of Default, an Officers' Certificate specifying such Default or Event of
Default and what action the Company is taking or proposes to take with respect
thereto.

Section 4.05.     Taxes; Payment of Additional Amounts.

     The Company shall pay, and shall cause each of its Subsidiaries to pay,
prior to delinquency, all material taxes, assessments, and governmental levies
except such as are contested in good faith and by appropriate proceedings or
where the failure to effect such payment is not adverse in any material respect
to the Holders of the Notes.

     All payments made by or on behalf of the Company on or with respect to the
Notes shall be made without withholding or deduction for any Taxes imposed by
any Canadian Taxing Authority, unless required by law or the interpretation or
administration thereof by the relevant Taxing Authority. If the Company or any
other payor is required to withhold or deduct any amount on account of Taxes
from any payment made on or with respect to the Notes, the Company shall:

          (a) make such withholding or deduction;

          (b) remit the full amount deducted or withheld to the relevant
     government authority in accordance with applicable law;

          (c) pay such additional amounts ("Additional Amounts") as may be
     necessary so that the net amount received by each Holder (including
     Additional Amounts) after such withholding or deduction shall not be less
     than the amount the Holder would have received if such Taxes had not been
     withheld or deducted;

          (d) furnish to the Holders, within 30 days after the date the payment
     of any Taxes is due, certified copies of tax receipts evidencing such
     payment by the Company;

          (e) indemnify and hold harmless each Holder (other than an Excluded
     Holder) for the amount of (i) any Taxes paid by such Holder as a result of
     payments made on or with respect to the Notes, (ii) any liability
     (including penalties, interest and expenses) arising therefrom or with
     respect thereto and (iii) any Taxes imposed with respect to any
     reimbursement under (i) or (ii), but excluding any such Taxes on such
     Holder's net income; and

          (f) at least 30 days prior to each date on which any Additional
     Amounts are payable, deliver to the Trustee an Officers' Certificate
     stating the amounts so payable and such other information necessary to
     enable the Trustee to pay such Additional Amounts to Holders on the payment
     date.


<PAGE>
                                      -46-


     Notwithstanding the foregoing, no Additional Amounts shall be payable to a
Holder in respect of a beneficial owner of a Note (an "Excluded Holder"):

          (a) with which the Company does not deal at arm's length (within the
     meaning of the Income Tax Act (Canada)) at the time of making such payment;
     or

          (b) which is subject to such Taxes by reason of its being connected
     with Canada or any province or territory thereof otherwise than by the mere
     acquisition, holding or disposition of Notes or the receipt of payments
     thereunder.

     The obligation of the Company to make payments of Additional Amounts
pursuant to this Section 4.05 shall survive any termination of this Indenture or
the defeasance of any rights under this Indenture.

Section 4.06.     Stay, Extension and Usury Laws.

     The Company covenants (to the extent that it may lawfully do so) that it
shall not at any time insist upon, plead, or in any manner whatsoever claim or
take the benefit or advantage of, any stay, extension or usury law wherever
enacted, now or at any time hereafter in force, that may affect the covenants or
the performance of this Indenture; and the Company (to the extent that it may
lawfully do so) hereby expressly waives all benefit or advantage of any such
law, and covenants that it shall not, by resort to any such law, hinder, delay
or impede the execution of any power herein granted to the Trustee, but shall
suffer and permit the execution of every such power as though no such law has
been enacted.

Section 4.07.     Restricted Payments.

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly:

          (a) declare or pay any dividend or make any other payment or
     distribution on account of the Company's or any of its Restricted
     Subsidiaries' Equity Interests (including, without limitation, any payment
     in connection with any merger or consolidation involving the Company or any
     of its Restricted Subsidiaries) or to the direct or indirect holders of the
     Company's or any of its Restricted Subsidiaries' Equity Interests in their
     capacity as such (other than dividends or distributions payable in Equity
     Interests (other than Disqualified Stock) of the Company or to the Company
     or a Restricted Subsidiary of the Company);

          (b) purchase, redeem or otherwise acquire or retire for value
     (including, without limitation, in connection with any merger or
     consolidation involving the Company) any Equity Interests of the Company or
     any direct or indirect parent of the Company (other than any such Equity
     Interests owned by the Company or any Restricted Subsidiary of the
     Company);

          (c) make any payment on or with respect to, or purchase, redeem,
     defease or otherwise acquire or retire for value any Indebtedness that is
     subordinated to the Notes, except a payment of interest or principal at the
     Stated Maturity thereof; or

          (d) make any Restricted Investment (all such payments and other
     actions set forth in clauses (a) through (d) above being collectively
     referred to as "Restricted Payments"),

     unless:


<PAGE>
                                      -47-


          (a) at the time of and after giving effect to such Restricted Payment,
     no Default or Event of Default shall have occurred and be continuing or
     would occur as a consequence thereof; and

          (b) the Company would, at the time of such Restricted Payment and
     after giving pro forma effect thereto as if such Restricted Payment had
     been made at the beginning of the applicable four-quarter period, have been
     permitted to incur at least $1.00 of additional Indebtedness pursuant to
     clause (i) or (ii) of the first paragraph of Section 4.09; and

          (c) such Restricted Payment, together with the aggregate amount of all
     other Restricted Payments made by the Company and its Restricted
     Subsidiaries after the Issue Date (excluding Restricted Payments permitted
     by clauses (b), (c), (d), (f), (g), (h)(i), (i), (j), (k) and (m)) is less
     than the sum, without duplication, of

               (i) Consolidated Cash Flow less 1.5 times Interest Expense for
          the period (taken as one accounting period) from the Issue Date to the
          end of the Company's most recently ended fiscal quarter for which
          internal financial statements are available at the time of such
          Restricted Payment (or, if such Consolidated Cash Flow for such period
          is a deficit, less 100% of such deficit), plus

               (ii) 100% of the aggregate net cash proceeds received by the
          Company (A) since the Issue Date as a contribution to its common
          equity capital or from the issue or sale of Equity Interests of the
          Company (other than Disqualified Stock) or from the issue or sale of
          Disqualified Stock or debt securities of the Company that have been
          converted into or exchanged for such Equity Interests (other than
          Equity Interests (or Disqualified Stock or debt securities) sold to a
          Subsidiary of the Company), plus the aggregate net cash proceeds
          received by the Company upon any such conversion or exchange and (B)
          without duplication, from the sale by the Company of its Subordinate
          Voting Shares in the Concurrent Equity Offering, plus

               (iii) 100% of the net reduction in Investments on and after the
          Issue Date, resulting from payments of interest on Indebtedness,
          dividends, repayments of loan or advances, or other transfers of
          property (but only to the extent such interest, dividends, repayments
          or other transfers of property are not included in the calculation of
          Consolidated Net Income), in each case to the Company or any of its
          Restricted Subsidiaries from any Person (including, without
          limitation, from Unrestricted Subsidiaries of the Company) or from
          redesignations of Unrestricted Subsidiaries as Restricted Subsidiaries
          (in each case, valued as provided in the definition of "Investments"),
          not to exceed in the case of any Person the amount of Restricted
          Investments previously made by the Company or any of its Restricted
          Subsidiaries in such Unrestricted Subsidiary (subsequent to the Issue
          Date) and in each such case which was treated as a Restricted Payment
          (other than any such Restricted Payment that was made pursuant to the
          provisions of paragraph (a) through (m) below).

     The preceding provisions shall not prohibit:

          (a) the payment of any dividend within 60 days after the date of
     declaration thereof, if at said date of declaration such payment would have
     complied with the provisions of this Indenture;

          (b) the redemption, repurchase, retirement, defeasance or other
     acquisition of any subordinated Indebtedness of the Company or of any
     Equity Interests of the Company or any Restricted Subsidiary in exchange
     for, or out of the net cash proceeds of the substantially concurrent sale
     (other than to a Subsidiary of the Company) of, Equity Interests of the
     Company (other than Disqualified Stock); provided that the amount of any
     such net cash proceeds that are utilized for any such redemption,
     repur-


<PAGE>
                                      -48-


     chase, retirement, defeasance or other acquisition shall be excluded from
     clause (c)(ii) of the preceding paragraph;

          (c) the defeasance, redemption, repurchase or other acquisition of
     subordinated Indebtedness of the Company with the net cash proceeds from an
     incurrence of Permitted Refinancing Indebtedness; provided that the amount
     of any such net cash proceeds that are utilized for any such defeasance,
     redemption, repurchase or other acquisition shall be excluded from clause
     (c)(ii) of the preceding paragraph;

          (d) Investments made out of the net cash proceeds from the issue and
     sale (other than to a Subsidiary of the Company) of Equity Interests (other
     than Disqualified Stock) of the Company; provided that the amount of any
     such net cash proceeds that are utilized for any such Investment shall be
     excluded from clause (c)(ii) of the preceding paragraph;

          (e) the repurchase, redemption or other acquisition or retirement for
     value of any Equity Interests of the Company pursuant to any management
     equity subscription agreement or stock option agreement and the repurchase
     of Equity Interests of the Company from employees, officers or directors of
     the Company or any of its Restricted Subsidiaries or their authorized
     representatives upon the death, disability or termination of employment of
     such officers, directors and employees in an aggregate amount not to exceed
     $5.0 million in any calendar year plus (i) the aggregate cash proceeds from
     any issuance during such calendar year of Equity Interests by the Company
     to employees, officers or directors of the Company and its Restricted
     Subsidiaries and (ii) the aggregate cash proceeds received by the Company
     or any of its Restricted Subsidiaries from any payments on life insurance
     policies in which the Company or any of its Restricted Subsidiaries is the
     beneficiary with respect to any employees, officers or directors of the
     Company or its Restricted Subsidiaries which proceeds are used to purchase
     Equity Interests of the Company held by any such employees, officers or
     directors;

          (f) Investments in Telecommunications Assets, provided that the
     aggregate fair market value of any such Investment, when taken together
     with all other Investments made pursuant to this clause (f) (measured on
     the date each such Investment was made), does not exceed $75.0 million;

          (g) Permitted Fiber Investments in Telecommunications Assets;

          (h) Investments in any Unrestricted Subsidiary of the Company, if
     either (i) such Investment is a Permitted Project Financing Investment or
     (ii) the aggregate fair market value of any such Investment, when taken
     together with all other Investments made pursuant to this subclause h(ii)
     (measured on the date each such Investment was made), does not exceed $20.0
     million;

          (i) Investments the payment for which consists exclusively of Equity
     Interests (other than Disqualified Stock) of the Company;

          (j) pro rata dividends or other distributions made by a Restricted
     Subsidiary of the Company to minority stockholders (or owners of an
     equivalent interest in the case of a Restricted Subsidiary that is not a
     corporation);

          (k) an Investment in any Person the primary business of which is
     Telecommunication Business in an amount not to exceed at any one time
     outstanding 20% of the Adjusted Consolidated Cash Flow, if positive,
     accrued on a cumulative basis during the period (taken as one accounting
     period)


<PAGE>
                                      -49-


     beginning on the first day of the first full fiscal quarter immediately
     following the Issue Date and ending on the last day of the last fiscal
     quarter preceding the date of such Investment;

          (l) payment when due of cash dividends on preferred stock of any
     Person that merges with or otherwise becomes a Restricted Subsidiary of the
     Company, which preferred stock is not issued in contemplation of such
     merger or other transaction, pursuant to the terms of such preferred stock
     as in effect on the date on which such Person merges with or otherwise
     becomes a Restricted Subsidiary of the Company; provided that the aggregate
     amount of cash dividends paid on any series of preferred stock so acquired
     by the Company pursuant to this clause (l) shall not exceed the aggregate
     liquidation preference of such series; and

          (m) the repurchase of Equity Interests of the Company deemed to occur
     upon the exercise of stock options if such Equity Interests represent a
     portion of the exercise price thereof;

     provided, however, that at the time of, and after giving effect to, any
     Restricted Payment permitted under clauses (b), (c), (d), (e), (h)(ii),
     (j), and (k) above, no Default in the payment of interest on the Notes or
     Event of Default exists or would occur as a consequence thereof.

     The amount of all Restricted Payments (other than cash) shall be the fair
market value on the date of the Restricted Payment of the asset(s) or securities
proposed to be transferred or issued by the Company or such Restricted
Subsidiary, as the case may be, pursuant to the Restricted Payment. The fair
market value of any assets or securities that are required to be valued by this
covenant shall be determined by the Board of Directors whose resolution with
respect thereto shall be delivered to the Trustee. The Board of Directors'
determination must be based upon an opinion or appraisal issued by an
accounting, appraisal or investment banking firm of national standing if the
fair market value exceeds $15.0 million. No such opinion or appraisal shall be
required for any Restricted Payment made pursuant to clause (g) above. In any
year in which the Company makes one or more Restricted Payments, the Company
shall include in its compliance certificate to the Trustee pursuant to Section
4.04 hereof, a certification stating that all such Restricted Payments are, or
were, permitted by this Indenture and shall set forth the basis upon which the
calculations required by this Section 4.07 were computed, together with a copy
of any fairness opinion or appraisal required hereby.

Section 4.08.    Dividend and Other Payment Restrictions Affecting Subsidiaries.

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, create or permit to exist or become
effective any encumbrance or restriction on the ability of any Restricted
Subsidiary to:

          (a) pay dividends or make any other distributions on its Capital Stock
     to the Company or any of the Company's Restricted Subsidiaries, or with
     respect to any other interest or participation in, or measured by, its
     profits, or pay any Indebtedness owed to the Company or any of the
     Company's Restricted Subsidiaries;

          (b) make loans or advances to the Company or any of the Company's
     Restricted Subsidiaries; or

          (c) transfer any of its properties or assets to the Company or any of
     the Company's Restricted Subsidiaries.


<PAGE>
                                      -50-


     However, the preceding restrictions shall not apply to encumbrances or
restrictions existing under or by reason of:

          (a) Existing Indebtedness as in effect on the Issue Date and any
     amendments, modifications, restatements, renewals, increases, supplements,
     refundings, replacements or refinancings thereof, provided that such
     amendments, modifications, restatements, renewals, increases, supplements,
     refundings, replacement or refinancings are no more restrictive with
     respect to such dividend and other payment restrictions than those
     contained in such Existing Indebtedness, as in effect on the Issue Date;

          (b) the Credit Facilities, this Indenture, the Euro Indenture, the
     Notes and the Exchange Notes, the Euro Notes and the Euro Exchange Notes,
     Qualified Subsidiary Indebtedness and Indebtedness ranking pari passu with
     the Notes; provided that with respect to Indebtedness ranking pari passu
     with the Notes such provisions are no more restrictive than those set forth
     in the Notes;

          (c) applicable law;

          (d) any instrument governing Indebtedness or Capital Stock of a Person
     acquired by the Company or any of its Restricted Subsidiaries as in effect
     at the time of such acquisition (except to the extent such Indebtedness was
     incurred in connection with or in contemplation of such acquisition), which
     encumbrance or restriction is not applicable to any Person, or the
     properties or assets of any Person, other than the Person, or the property
     or assets of the Person, so acquired; provided that, in the case of
     Indebtedness, such Indebtedness was permitted by the terms of this
     Indenture to be incurred;

          (e) customary non-assignment provisions restricting subletting or
     assignment in leases or other agreements entered into in the ordinary
     course of business and consistent with past practices;

          (f) purchase money obligations for property acquired in the ordinary
     course of business that impose restrictions on the property so acquired of
     the nature described in clause (c) of the preceding paragraph;

          (g) any agreement for the sale or other disposition of a Restricted
     Subsidiary that restricts distributions by such Restricted Subsidiary
     pending its sale or other disposition, provided that the consummation of
     such transaction would not result in a Default or an Event of Default, that
     such restriction terminates if such transaction is not consummated and that
     the consummation or abandonment of such transaction occurs within one year
     of the date such agreement was entered into;

          (h) Permitted Refinancing Indebtedness, provided that the restrictions
     contained in the agreements governing such Permitted Refinancing
     Indebtedness are no more restrictive than those contained in the agreements
     governing the Indebtedness being refinanced;

          (i) Liens securing Indebtedness otherwise permitted to be incurred
     pursuant to the provisions of Section 4.12 that limit the right of the
     Company or any of its Restricted Subsidiaries to dispose of the assets
     subject to such Lien;

          (j) customary limitations on the disposition or distribution of assets
     or property in joint venture agreements and other similar agreements
     entered into in the ordinary course of business; and

          (k) restrictions on cash or other deposits or net worth imposed by
     customers under contracts entered into in the ordinary course of business.


<PAGE>
                                      -51-


          (l) encumbrances and restrictions in Indebtedness incurred by Foreign
     Subsidiaries in accordance with Section 4.09; and

          (m) any Indebtedness or any agreement pursuant to which such
     Indebtedness was issued if (A) the encumbrance or restriction applies only
     upon a payment or financial covenant default or event of default contained
     in such Indebtedness or agreement and (B) the encumbrance or restriction is
     not materially more disadvantageous to the Holders of the Notes than is
     customary in comparable financings (as determined in good faith by the
     Board of Directors of the Company).

Section 4.09.     Incurrence of Indebtedness and Issuance of Preferred Stock.

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, create, incur, issue, assume, guarantee
or otherwise become directly or indirectly liable, contingently or otherwise,
with respect to (collectively, "incur") any Indebtedness (including Acquired
Debt), and the Company shall not issue any Disqualified Stock and shall not
permit any of its Restricted Subsidiaries to issue any shares of preferred
stock; provided, however, that the Company may incur Indebtedness (including
Acquired Debt) and issue Disqualified Stock and any Restricted Subsidiary may
incur Acquired Debt, if either:

          (i) the Consolidated Leverage Ratio at the end of the Company's most
     recently ended full fiscal quarter (the "Reference Period") for which a
     consolidated balance sheet of the Company is available immediately
     preceding the date on which such additional Indebtedness is incurred or
     such Disqualified Stock is issued would have been less than 5.0 to 1.0,
     determined on a pro forma basis (including a pro forma application of the
     net proceeds therefrom), as if the additional Indebtedness had been
     incurred, or the Disqualified Stock had been issued, as the case may be, at
     the beginning of the Reference Period; or

          (ii) the Consolidated Capital Ratio at the end of the Reference Period
     would have been less than 2.0 to 1.0, determined after giving effect to the
     incurrence or issuance of such Indebtedness or Disqualified Stock and, to
     the extent set forth in the definitions used herein, on a pro forma basis
     (including, to the extent set forth in the definitions used herein, a pro
     forma application of the net proceeds therefrom).

     The first paragraph of this Section 4.09 shall not prohibit the incurrence
of any of the following items of Indebtedness (collectively, "Permitted Debt"):

          (a) the incurrence by the Company or any of its Restricted
     Subsidiaries of Indebtedness under Credit Facilities or Permitted Vendor
     Facilities; provided that the aggregate principal amount of all
     Indebtedness of the Company and its Restricted Subsidiaries outstanding
     under all Credit Facilities or Permitted Vendor Facilities after giving
     effect to such incurrence (with letters of credit being deemed to have a
     principal amount equal to the maximum potential liability of the Company
     thereunder) does not exceed an amount equal to $725.0 million less the
     aggregate amount of all Net Proceeds of Asset Sales applied by the Company
     or any of its Restricted Subsidiaries since the Issue Date to permanently
     repay Indebtedness under a Credit Facility pursuant to Section 4.10 hereof;

          (b) the incurrence by the Company and its Restricted Subsidiaries of
     Existing Indebtedness;

          (c) the incurrence by the Company of Indebtedness represented by the
     Notes, the Euro Notes, the Exchange Notes and the Euro Exchange Notes;


<PAGE>
                                      -52-


          (d) the incurrence by the Company or any of its Restricted
     Subsidiaries of Purchase Money Indebtedness and Vendor Financing
     Indebtedness provided (A) that the amount thereof does not exceed 100% of
     the Company's and its Restricted Subsidiaries' aggregate cost (determined
     in accordance with GAAP in good faith by the Board of Directors) of the
     construction, acquisition, development, engineering, installation and
     improvement of the applicable Telecommunications Assets and (B) in the case
     of the incurrence of either Purchase Money Indebtedness or Vendor Financing
     Indebtedness by a Restricted Subsidiary, such Indebtedness shall be
     Qualified Subsidiary Indebtedness;

          (e) the incurrence by the Company or any of its Restricted
     Subsidiaries of Permitted Refinancing Indebtedness in exchange for, or the
     net proceeds of which are used to refund, refinance or replace,
     Indebtedness (other than intercompany Indebtedness) that was permitted by
     this Indenture to be incurred under the first paragraph of this Section or
     clauses (b), (c), (d), (l), (n), (o) or (p) of this paragraph;

          (f) the incurrence by the Company or any of its Restricted
     Subsidiaries of intercompany Indebtedness between or among the Company and
     any of its Restricted Subsidiaries and the issuance of preferred stock by a
     Restricted Subsidiary to the Company or another Restricted Subsidiary of
     the Company; provided, however, that:

               (i) if the Company is the obligor on such Indebtedness, such
          Indebtedness must be expressly subordinated to the prior payment in
          full in cash of all Obligations with respect to the Notes; and

               (ii) (A) any subsequent issuance or transfer of Equity Interests
          that results in any such Indebtedness or preferred stock being held by
          a Person other than the Company or a Restricted Subsidiary thereof and
          (B) any sale or other transfer of any such Indebtedness or preferred
          stock to a Person that is not either the Company or a Restricted
          Subsidiary thereof; shall be deemed, in each case, to constitute an
          incurrence of such Indebtedness by the Company or such Restricted
          Subsidiary, as the case may be, that was not permitted by this clause
          (f);

          (g) the incurrence by the Company or any of its Restricted
     Subsidiaries of Hedging Obligations that are incurred for the purpose of
     fixing or hedging interest or foreign currency exchange rate risk with
     respect to any floating rate Indebtedness or foreign currency based
     Indebtedness, respectively, that is permitted by the terms of this
     Indenture to be outstanding; provided that the notional amount of any such
     Hedging Obligation does not exceed the amount of Indebtedness or other
     liability to which such Hedging Obligation relates; and provided further
     that such Hedging Obligations are not incurred for speculative purposes;

          (h) the guarantee by the Company or any of its Restricted Subsidiaries
     of Indebtedness of the Company or any Restricted Subsidiary of the Company
     that was permitted to be incurred by another provision of this covenant;

          (i) the accrual of interest, accretion or amortization of original
     issue discount, the payment of interest on any Indebtedness in the form of
     additional Indebtedness with the same terms, and the payment of dividends
     on Disqualified Stock in the form of additional shares of the same class of
     Disqualified Stock; provided, in each such case, that the amount thereof is
     included in Fixed Charges of the Company as accrued;


<PAGE>
                                      -53-


          (j) the Company and its Restricted Subsidiaries may incur Indebtedness
     solely in respect of bankers acceptances, letters of credit and performance
     bonds or similar arrangements, all in the ordinary course of business
     (other than to the extent not supporting Indebtedness);

          (k) the incurrence by the Company or any of its Restricted
     Subsidiaries arising from agreements of the Company or any of its
     Restricted Subsidiaries providing for indemnification, adjustment of
     purchase price, earn out or other similar obligation, in each case,
     incurred or assumed in connection with the disposition of any business,
     assets or Restricted Subsidiary of the Company or any of its Restricted
     Subsidiaries, other than guarantees of Indebtedness incurred by any Person
     acquiring all or any portion of such business, assets or Restricted
     Subsidiary for the purpose of financing such acquisition;

          (l) the incurrence of Indebtedness by Foreign Subsidiaries not to
     exceed $50.0 million (or the equivalent amount thereof, in other foreign
     currencies);

          (m) the incurrence by the Company or any of its Restricted
     Subsidiaries of Acquired Debt in an aggregate amount not to exceed $100.0
     million at any time outstanding;

          (n) Indebtedness of the Company not to exceed, at any one time
     outstanding, two times the net cash proceeds received by the Company after
     the Measurement Date from the issuance and sale of its Equity Interest
     (other than Disqualified Stock) to a Person that is not a Subsidiary of the
     Company, to the extent such net cash proceeds have not been used pursuant
     to (i) clause (c)(ii) of the first paragraph of Section 4.07 or (ii)
     clauses (b) or (d) of the second paragraph of Section 4.07 to make a
     Restricted Payment; and

          (o) the incurrence by the Company or any of its Restricted
     Subsidiaries of additional Indebtedness in an aggregate principal amount
     (or accreted value, as applicable) at any time outstanding not to exceed
     $50.0 million.

     Indebtedness or preferred stock of any Person which is outstanding at the
time such Person becomes a Restricted Subsidiary of the Company (including upon
designation of any Subsidiary or other Person as a Restricted Subsidiary) or is
merged with or into or consolidated with the Company or a Restricted Subsidiary
of the Company shall be deemed to have been incurred at the time such Person
becomes such a Restricted Subsidiary of the Company or is merged with or into or
consolidated with the Company or a Restricted Subsidiary of the Company, as
applicable.

     Notwithstanding any other provisions of this Section 4.09, the maximum
amount of Indebtedness that the Company or a Restricted Subsidiary may incur
shall not be deemed to be exceeded solely as a result of fluctuations in the
exchange rates of currencies.

     For purposes of determining compliance with this Section 4.09, in the event
that an item of proposed Indebtedness meets the criteria of more than one of the
categories of Permitted Debt described in clauses (a) through (p) above, or is
entitled to be incurred pursuant to the first paragraph of this Section 4.09,
the Company shall be permitted to classify such item of Indebtedness on the date
of its incurrence, or later reclassify all or a portion of such item of
Indebtedness, in any manner that complies with this Section 4.09.


<PAGE>
                                      -54-


Section 4.10.     Limitation on Asset Sales

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, consummate an Asset Sale unless:

          (a) the Company (or the Restricted Subsidiary, as the case may be)
     receives consideration at the time of such Asset Sale at least equal to the
     fair market value of the assets or Equity Interests issued or sold or
     otherwise disposed of;

          (b) such fair market value is determined by the Company's Board of
     Directors and evidenced by a resolution of the Board of Directors set forth
     in an Officers' Certificate delivered to the Trustee;

          (c) at least 80% of the consideration therefor received by the Company
     or such Restricted Subsidiary is in the form of cash or Telecommunications
     Assets. For purposes of this provision, each of the following shall be
     deemed to be cash:

               (i) any liabilities (as shown on the Company's or such Restricted
          Subsidiary's most recent balance sheet), of the Company or any
          Restricted Subsidiary (other than contingent liabilities and
          liabilities that are by their terms subordinated to the Notes) that
          are assumed by the transferee of any such assets pursuant to a
          customary novation agreement that releases the Company or such
          Restricted Subsidiary from further liability;

               (ii) any securities, notes or other obligations received by the
          Company or any such Restricted Subsidiary from such transferee that
          are within 180 days converted by the Company or such Restricted
          Subsidiary into cash (to the extent of the cash received in that
          conversion); and

          (d) the Company delivers to the Trustee, with respect to any Asset
     Sale involving aggregate consideration in excess of $100.0 million, an
     opinion as to the fairness to the Company of such Asset Sale from a
     financial point of view issued by an accounting, appraisal or investment
     banking firm of national standing.

     Within 360 days after the receipt of any Net Proceeds from an Asset Sale,
the Company or such Restricted Subsidiary, as applicable, may apply such Net
Proceeds at its option:

          (a) to permanently repay or retire

               (i) secured Indebtedness of the Company, including Indebtedness
          under Credit Facilities, or

               (ii) Indebtedness of any Restricted Subsidiary of the Company (in
          each case other than any Indebtedness owed to the Company or any
          Restricted Subsidiary); or

          (b) to acquire Telecommunications Assets.

Pending the final application of any such Net Proceeds, the Company may
temporarily reduce revolving credit borrowings or otherwise invest such Net
Proceeds in any manner that is not prohibited by this Indenture.


<PAGE>
                                      -55-


     Any Net Proceeds from Asset Sales that are not applied or invested as
provided in the preceding paragraph shall constitute Excess Proceeds. When the
aggregate amount of Excess Proceeds exceeds $10.0 million, the Company shall
make an Asset Sale Offer to all Holders of Notes and all holders of other
Indebtedness that is pari passu with the Notes, including the Euro Notes,
containing provisions similar to those set forth in this Indenture with respect
to offers to purchase or redeem with the proceeds of sales of assets to purchase
the maximum principal amount of Notes and such other pari passu Indebtedness
that may be purchased out of the Excess Proceeds. The offer price in any Asset
Sale Offer shall be equal to 100% of principal amount plus accrued and unpaid
interest, if any, thereon to the date of purchase and shall be payable in cash.
If any Excess Proceeds remain after consummation of an Asset Sale Offer, the
Company may use such Excess Proceeds for any purpose not otherwise prohibited by
this Indenture. If the aggregate principal amount of Notes and such other pari
passu Indebtedness tendered into such Asset Sale Offer exceeds the amount of
Excess Proceeds, the Trustee shall select the Notes to be purchased on a pro
rata basis. Upon completion of each Asset Sale Offer, the amount of Excess
Proceeds shall be reset at zero.

Section 4.11.     Transactions with Affiliates.

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, make any payment to, or sell, lease, transfer or otherwise
dispose of any of its properties, assets or securities to, or purchase any
property or assets from, or enter into or make or amend any transaction,
contract, agreement, understanding, loan, advance or guarantee with, or for the
benefit of, any Affiliate (each, an "Affiliate Transaction"), unless:

          (a) such Affiliate Transaction is on terms that are no less favorable
     to the Company or the relevant Restricted Subsidiary than those that would
     have been obtained in a comparable transaction by the Company or such
     Restricted Subsidiary with a Person that is not an Affiliate; and

          (b) the Company delivers to the Trustee:

               (i) with respect to any Affiliate Transaction or series of
          related Affiliate Transactions involving aggregate consideration in
          excess of $5.0 million, a Board Resolution certifying that such
          Affiliate Transaction complies with Section 4.11 and that such
          Affiliate Transaction has been approved by a majority of the
          disinterested members of the Board of Directors and is in the best
          interests of the Company or such Restricted Subsidiary; and

               (ii) with respect to any Affiliate Transaction or series of
          related Affiliate Transactions involving aggregate consideration in
          excess of $10.0 million, an opinion as to the fairness to the Holders
          of such Affiliate Transaction from a financial point of view issued by
          an accounting, appraisal or investment banking firm of national
          standing.

     The following items shall not be deemed to be Affiliate Transactions and,
therefore, shall not be subject to the provisions of the prior paragraph:

          (a) reasonable fees and compensation paid to, and indemnity provided
     on behalf of, officers, directors, employees, agents or consultants of the
     Company or any of its Restricted Subsidiaries as determined in good faith
     by the Board of Directors or senior management of the Company;

          (b) transactions between or among the Company and any of the Company's
     Restricted Subsidiaries;


<PAGE>
                                      -56-


          (c) any sale or other issuance of Equity Interests (other than
     Disqualified Stock) of the Company;

          (d) Restricted Payments that are permitted by the provisions of
     Section 4.07 or by clauses (1), (3), (7), (8) or (9) of the definition of
     "Permitted Investments";

          (e) any agreement or arrangement as in effect on the Issue Date or any
     amendment thereto or any transaction contemplated thereby (including
     pursuant to any amendment thereto) in any replacement agreement or
     arrangement thereto so long as any such amendment or replacement agreement
     or arrangement is not more disadvantageous to the Company or its Restricted
     Subsidiaries, as the case may be, in any material respect than the original
     agreement as in effect on the Issue Date;

          (f) transactions involving aggregate consideration of up to $25.0
     million between the Company or its Restricted Subsidiaries and Ledcor Inc.
     or any of its Subsidiaries (other than the Company and its Restricted
     Subsidiaries); provided, that the Company delivers to the Trustee a Board
     Resolution stating that such Affiliate Transaction has been approved by a
     majority of the disinterested members of the Board of Directors; and

          (g) transactions with Urbanlink pertaining to the Canadian
     telecommunications arrangements consistent with the description in the
     Offering Memorandum under "Related Party Transactions -- Transactions with
     Ledcor -- Canadian telecommunications arrangements," and any contracts,
     transactions and arrangements in connection therewith.

Section 4.12.     Liens.

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, directly or indirectly, create, incur, assume or suffer to
exist any Lien of any kind on any asset now owned or hereafter acquired, except
Permitted Liens, without providing that the Notes shall be secured equally and
ratably with the Indebtedness so secured for so long as such obligations are so
secured; provided that if the Indebtedness so secured is subordinated to the
Notes, the Notes shall be secured by a Lien senior to the Lien securing such
secured Indebtedness to the same extent as the Notes are senior to such
Indebtedness.

Section 4.13.     Corporate Existence.

     Subject to Article 5 hereof, the Company shall do or cause to be done all
things necessary to preserve and keep in full force and effect (i) its corporate
existence, and the corporate, partnership or other existence of each of its
Subsidiaries, in accordance with the respective organizational documents (as the
same may be amended from time to time) of the Company or any such Subsidiary and
(ii) the rights (charter and statutory), licenses and franchises of the Company
and its Subsidiaries; provided, however, that the Company shall not be required
to preserve any such right, license or franchise, or the corporate, partnership
or other existence of any of its Subsidiaries, if the Board of Directors shall
determine that the preservation thereof is no longer desirable in the conduct of
the business of the Company and its Subsidiaries, taken as a whole, and that the
loss thereof is not adverse in any material respect to the Holders of the Notes.

Section 4.14.     Repurchase at the Option of Holders upon a Change of Control.

     Upon the occurrence of a Change of Control, each Holder of Notes shall have
the right to require the Company to repurchase all or any part (equal to $1,000
or an integral multiple thereof) of that Holder's Notes pursuant to the Change
of Control Offer. In the Change of Control Offer, the Company shall offer (the
"Change


<PAGE>
                                      -57-


of Control Offer") a payment (the "Change of Control Payment") in cash equal to
101% of the aggregate principal amount of Notes repurchased plus accrued and
unpaid interest, if any, thereon to the date of purchase.

     Within 20 days following any Change of Control, the Company shall mail a
notice to each Holder (with a copy to the Trustee) describing the transaction or
transactions that constitute the Change of Control and stating:

          (a) the purchase price and the purchase date, which shall not exceed
     30 Business Days from the date such notice is mailed (the "Change of
     Control Payment Date");

          (b) that any Note not tendered shall continue to accrue interest;

          (c) that, unless the Company defaults in the payment of the Change of
     Control Payment, all Notes accepted for payment pursuant to the Change of
     Control Offer shall cease to accrue interest after the Change of Control
     Payment Date;

          (d) that Holders electing to have any Notes purchased pursuant to a
     Change of Control Offer shall be required to surrender the Notes, with the
     form entitled, "Option of Holder to Elect Purchase" on the reverse of the
     Notes completed, to the Paying Agent at the address specified in the notice
     prior to the close of business on the third Business Day preceding the
     Change of Control Payment Date;

          (e) that Holders shall be entitled to withdraw their election if the
     Paying Agent receives, not later than the close of business on the second
     Business Day preceding the Change of Control Payment Date, a telegram,
     telex, facsimile transmission or letter setting forth the name of the
     Holder, the principal amount of Notes delivered for purchase, and a
     statement that such Holder is withdrawing his election to have the Notes
     purchased; and

          (f) that Holders whose Notes are being purchased only in part shall be
     issued new Notes equal in principal amount to the unpurchased portion of
     the Notes surrendered, which unpurchased portion must be equal to $1,000 in
     principal amount or an integral multiple thereof. The Company shall comply
     with the requirements of 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 connection with the repurchase of the Notes
     as a result of a Change of Control.

     On the Change of Control Payment Date, the Company shall, to the extent
lawful:

          (a) accept for payment all Notes or portions thereof properly tendered
     pursuant to the Change of Control Offer;

          (b) deposit with the Paying Agent an amount equal to the Change of
     Control Payment plus accrued and unpaid interest, if any, thereon in
     respect of all Notes or portions thereof so tendered; and

          (c) deliver or cause to be delivered to the Trustee the Notes so
     accepted together with an Officers' Certificate stating the aggregate
     principal amount of Notes or portions thereof being purchased by the
     Company.

     The Paying Agent shall promptly mail to each Holder of Notes so tendered
the Change of Control Payment plus accrued and unpaid interest, if any, thereon
for such Notes, and the Trustee shall promptly authenticate and mail (or cause
to be transferred by book entry) to each Holder a new Note equal in principal
amount to any unpurchased portion of the Notes surrendered, if any; provided
that each such new Note shall be in a principal


<PAGE>
                                      -58-


amount of $1,000 or an integral multiple thereof. The Company shall publicly
announce the results of the Change of Control Offer on or as soon as practicable
after the Change of Control Payment Date.

     The provisions described above that require the Company to make a Change of
Control Offer following a Change of Control shall be applicable regardless of
whether or not any other provisions in this Indenture are applicable. Except as
described above with respect to a Change of Control, this Indenture does not
contain provisions that permit the Holders of the Notes to require that the
Company repurchase or redeem the Notes in the event of a takeover,
recapitalization or similar transaction.

     Notwithstanding any other provision of this Section 4.14, the Company shall
not be required to make a Change of Control Offer upon a Change of Control if a
third party makes the Change of Control Offer in the manner, at the times and
otherwise in compliance with the requirements set forth in this Indenture
applicable to a Change of Control Offer made by the Company and purchases all
Notes validly tendered and not withdrawn under such Change of Control Offer.

Section 4.15.     No Senior Subordinated Debt

     Notwithstanding the provisions of Section 4.09 hereof, the Company shall
not incur any Indebtedness (including Permitted Debt) that is contractually
subordinated in right of payment to any other Indebtedness of the Company unless
such Indebtedness is also contractually subordinated in right of payment to the
Notes on substantially identical terms; provided, however, that no Indebtedness
of the Company shall be deemed to be contractually subordinated in right of
payment to any other Indebtedness of the Company solely by virtue of being
unsecured.

Section 4.16.     Issuances of Guarantees by Restricted Subsidiaries.

     The Company shall not permit any Restricted Subsidiary, directly or
indirectly, to guarantee, assume or in any other manner become liable with
respect to any Indebtedness of the Company which is pari passu (other than any
Indebtedness incurred under a Credit Facility) with or subordinate in right of
payment to the Notes ("Guaranteed Indebtedness"), unless (i) such Restricted
Subsidiary simultaneously executes and delivers a supplemental indenture to this
Indenture providing for a guarantee (a "Subsidiary Guarantee") of payment of the
Notes by such Restricted Subsidiary and (ii) such Restricted Subsidiary waives
and shall not in any manner whatsoever claim, or take the benefit or advantage
of, any rights of reimbursement, indemnity or subrogation or any other rights
against the Company or any other Restricted Subsidiary as a result of any
payment by such Restricted Subsidiary under its Subsidiary Guarantee; provided
that this paragraph shall not be applicable to any guarantee of any Restricted
Subsidiary that existed at the time such Person became a Restricted Subsidiary
and was not incurred in connection with, or in contemplation of, such Person
becoming a Restricted Subsidiary. If the Guaranteed Indebtedness is (A) pari
passu with the Notes, then the guarantee of such Guaranteed Indebtedness shall
be pari passu with, or subordinated to, the Subsidiary Guarantee or (B)
subordinated to the Notes, then the guarantee of such Guaranteed Indebtedness
shall be subordinated to the Subsidiary Guarantee at least to the extent that
the Guaranteed Indebtedness is subordinated to the Notes.

     Notwithstanding the foregoing, any Subsidiary Guarantee by a Restricted
Subsidiary may provide by its terms that it shall be automatically and
unconditionally released and discharged upon (i) any sale, exchange or transfer,
to any Person that is 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
of 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.


<PAGE>
                                      -59-


Section 4.17.     Designation of Restricted and Unrestricted Subsidiaries.

     The Board of Directors may designate any Restricted Subsidiary to be an
Unrestricted Subsidiary if that designation would not cause a Default. If a
Restricted Subsidiary is designated as an Unrestricted Subsidiary, all
outstanding Investments owned by the Company and its Restricted Subsidiaries in
the Subsidiary so designated shall be deemed to be an Investment made as of the
time of such designation and shall reduce the amount available for Restricted
Payments under the first paragraph of Section 4.07. All such outstanding
Investments shall be valued at their fair market value at the time of such
designation; provided that any determination of fair market value equal to or
greater than $100.0 million shall be determined by an independent accounting,
appraisal or investment banking firm of national standing. That designation
shall only be permitted if such Restricted Payment would be permitted at that
time and if such Restricted Subsidiary otherwise meets the definition of an
Unrestricted Subsidiary. The Board of Directors may redesignate any Unrestricted
Subsidiary to be a Restricted Subsidiary if the redesignation would not cause a
Default and such redesignation shall increase the amount available for
Restricted Payments under the first paragraph of Section 4.07 as provided
therein or Permitted Investments, as applicable.

     As of the date hereof, all of the Company's subsidiaries other than the
Hibernia Subsidiaries are Restricted Subsidiaries.

Section 4.18.     Payments for Consent.

     The Company shall not, and shall not permit any of its Subsidiaries to,
directly or indirectly, pay or cause to be paid any consideration to or for the
benefit of any Holder of Notes for or as an inducement to any consent, waiver or
amendment of any of the terms or provisions of this Indenture or the Notes
unless such consideration is offered to be paid and is paid to all Holders of
the Notes that consent, waive or agree to amend in the time frame set forth in
the solicitation documents relating to such consent, waiver or agreement.

Section 4.19.     Business Activities.

     The Company shall not, and shall not permit any of its Restricted
Subsidiaries to, engage to any material extent in any business other than the
Telecommunications Business.

                                    ARTICLE 5
                                   SUCCESSORS

Section 5.01.     Amalgamation, Merger, Consolidation, or Sale of Assets.

     The Company shall not, directly or indirectly: (1) amalgamate or
consolidate or merge with or into (whether or not the Company is the surviving
corporation); or (2) or sell, assign, transfer, convey or otherwise dispose of
all or substantially all of its properties or assets in one or more related
transactions to, another Person; unless:

          (a) either: (i) the Company is the surviving corporation; or (ii) the
     Person formed by or surviving any such amalgamation, consolidation or
     merger (if other than the Company) or to which such sale, assignment,
     transfer, conveyance or other disposition shall have been made is a
     corporation organized or existing under the laws of Canada or any province
     thereof or the United States, any state thereof or the District of
     Columbia;


<PAGE>
                                      -60-


          (b) the Person formed by or surviving any such amalgamation,
     consolidation or merger (if other than the Company) or the Person to which
     such sale, assignment, transfer, conveyance or other disposition shall have
     been made assumes all the obligations of the Company under the Notes, the
     Exchange Notes, this Indenture and the Registration Rights Agreement
     pursuant to agreements reasonably satisfactory to the Trustee;

          (c) no Default or Event of Default (or an event that, with the passing
     of time or giving of notice or both, would constitute an Event of Default)
     shall exist or shall occur immediately after giving effect on a pro forma
     basis to such transaction;

          (d) the Company or the Person formed or surviving any such
     amalgamation, consolidation or merger (if other than the Company) or to
     which such sale, assignment, transfer, conveyance or other disposition has
     been made will, on the date of such transaction after giving pro forma
     effect thereto and any related financing transactions as if the same had
     occurred at the beginning of the applicable Reference Period, be permitted
     to incur at least $1.00 of additional Indebtedness pursuant to the
     Consolidated Leverage Ratio test or the Consolidated Capital Ratio test set
     forth in the first paragraph of Section 4.09;

          (e) the transaction shall not result in the Company or the Person
     formed by or surviving any such amalgamation, consolidation or merger (if
     other than the Company) being required to make any deduction or withholding
     on account of Taxes as described under Section 3.07(c) and Section 4.05
     from any payment under or in respect of the Notes that the Company would
     not have been required to make had such transaction or series of related
     transactions not occurred; and

          (f) the Company shall have delivered to the Trustee an Officers'
     Certificate and an Opinion of Counsel, each stating that such amalgamation,
     consolidation, merger or transfer and such supplemental indenture, if any,
     comply with this Indenture.

     In addition, the Company may not, directly or indirectly, lease all or
substantially all of its properties or assets, in one or more related
transactions, to any other Person. For purposes of the foregoing, the transfer
(by assignment, sale or otherwise) of all or substantially all of the properties
and assets of one or more Subsidiaries, the Company's interest in which
constitutes all or substantially all of the properties and assets of the
Company, shall be deemed to be the transfer of all or substantially all of the
properties and assets of the Company. The provisions of this Section 5.01 shall
not apply to a sale, assignment, transfer, conveyance or other disposition of
assets between or among the Company and any of its Wholly-Owned Restricted
Subsidiaries.

Section 5.02.     Successor Corporation Substituted.

     Upon any amalgamation, consolidation or merger or any sale, assignment,
transfer, lease, conveyance or other disposition of all or substantially all of
the assets of the Company in accordance with Section 5.01, the successor
corporation formed by such amalgamation or consolidation or into which the
Company is merged or to which such transfer is made shall succeed to and (except
in the case of a lease) be substituted for, and may exercise every right and
power of, the Company under this Indenture with the same effect as if such
successor corporation had been named therein as the Company, and (except in the
case of a lease) the Company shall be released from the obligations under the
Notes, and this Indenture except with respect to any obligations that arise
from, or are related to, such transaction.


<PAGE>
                                      -61-


                                    ARTICLE 6
                              DEFAULTS AND REMEDIES

Section 6.01.     Events of Default.

     An "Event of Default" occurs if:

          (a) the Company defaults in the payment when due of interest on, or
     Additional Amounts, if any, with respect to, the Notes and such default
     continues for a period of 30 days;

          (b) the Company defaults in the payment when due of principal of or
     premium, if any, on the Notes;

          (c) the Company or any of its Restricted Subsidiaries fails to comply
     with any of the provisions of Article 5 hereof, or any of the provisions of
     Sections 4.07, 4.09 or 4.11;

          (d) the Company or any of its Restricted Subsidiaries fails to observe
     or perform any of the provisions of Sections 4.10 and 4.14 for 15 days
     after notice to the Company by the Trustee or to the Company and the
     Trustee by the Holders of at least 25% of the aggregate principal amount of
     the Notes (including Additional Senior Notes, if any) then outstanding;

          (e) the Company or any of its Restricted Subsidiaries fails to observe
     or perform any other covenant, representation, warranty or other agreement
     in this Indenture or the Notes for 60 days after written notice to the
     Company by the Trustee or to the Company and the Trustee by the Holders of
     at least 25% of the aggregate principal amount of the Notes then
     outstanding;

          (f) the Company voluntarily relinquishes any of its rights under the
     Non-Competition Agreement or fails for 30 days after written notice thereof
     has been given to the Company by the Trustee or to the Company and the
     Trustee by the Holders of at least 25% in aggregate principal amount of the
     Notes then outstanding to enforce any of such rights, in each case which is
     materially detrimental to the interests of the Company or the Holders;

          (g) the Company defaults under any mortgage, indenture or instrument
     under which there may be issued or by which there may be secured or
     evidenced any Indebtedness for money borrowed (or the payment of which is
     guaranteed by the Company or any of its Restricted Subsidiaries) whether
     such Indebtedness or guarantee now exists, or is created after the date of
     the Indenture, if that default:

               (i) is caused by a failure to pay principal of or premium, if
          any, on such Indebtedness prior to the expiration of the grace period
          provided in such Indebtedness on the date of such default (a "Payment
          Default"); or

               (ii) results in the acceleration of such Indebtedness prior to
          its express maturity, and, in each case, the principal amount of any
          such Indebtedness, together with the principal amount of any other
          such Indebtedness under which there has been a Payment Default or the
          maturity of which has been so accelerated, aggregates $10.0 million or
          more;

          (h) the Company or any of its Restricted Subsidiaries fails to pay
     final judgments which are non-appealable aggregating in excess of $10.0
     million (net of applicable insurance coverage which


<PAGE>
                                      -62-


     is acknowledged in writing by the insurer), which judgments are not paid,
     discharged or stayed for a period of 60 days; and

          (i) the Company or any of its Restricted Subsidiaries pursuant to or
     within the meaning of Bankruptcy Law:

               (i) commences a voluntary case,

               (ii) consents to the entry of an order for relief against it in
          an involuntary case,

               (iii) consents to the appointment of a custodian of it or for all
          or substantially all of its property,

               (iv) makes a general assignment for the benefit of its creditors,
          or

               (v) generally is not paying its debts as they become due; or

          (j) a court of competent jurisdiction enters an order or decree under
     any Bankruptcy Law that:

               (i) is for relief against the Company or any of its Restricted
          Subsidiaries in an involuntary case;

               (ii) appoints a custodian of the Company or any of its Restricted
          Subsidiaries or for all or substantially all of the property of the
          Company or any of its Restricted Subsidiaries; or

               (iii) orders the liquidation of the Company or any of its
          Restricted Subsidiaries;

     and the order or decree remains unstayed and in effect for 60 consecutive
     days.

Section 6.02.     Acceleration.

     If any Event of Default (other than an Event of Default specified in clause
(i) or (j) of Section 6.01 hereof with respect to the Company, any Restricted
Subsidiary that is a Significant Subsidiary or any group of Restricted
Subsidiaries that, taken together, would constitute a Significant Subsidiary)
occurs and is continuing, the Trustee by notice to the Company or the Holders of
at least 25% in principal amount of the then outstanding Notes by notice to the
Company and the Trustee may declare all the Notes to be due and payable
immediately.

     Notwithstanding the foregoing, if an Event of Default specified in clause
(i) or (j) of Section 6.01 hereof occurs with respect to the Company, any
Restricted Subsidiary that is a Significant Subsidiary or any group of
Restricted Subsidiaries that, taken together, would constitute a Significant
Subsidiary, all outstanding Notes shall be due and payable immediately without
further action or notice. The Holders of a majority in aggregate principal
amount of the then outstanding Notes by written notice to the Trustee may on
behalf of all of the Holders rescind an acceleration and its consequences if the
rescission would not conflict with any judgment or decree and if all existing
Events of Default (except nonpayment of principal, interest or premium that has
become due solely because of the acceleration) have been cured or waived.


<PAGE>
                                      -63-


Section 6.03.     Other Remedies.

     If an Event of Default occurs and is continuing, the Trustee may pursue any
available remedy to collect the payment of principal, premium, if any, and
interest on the Notes or to enforce the performance of any provision of the
Notes or this Indenture.

     The Trustee may maintain a proceeding even if it does not possess any of
the Notes or does not produce any of them in the proceeding. A delay or omission
by the Trustee or any Holder of a Note in exercising any right or remedy
accruing upon an Event of Default shall not impair the right or remedy or
constitute a waiver of or acquiescence in the Event of Default. All remedies are
cumulative to the extent permitted by law.

Section 6.04.     Waiver of Past Defaults.

     Subject to Section 6.02, Holders of not less than a majority in aggregate
principal amount of the then outstanding Notes by notice to the Trustee may on
behalf of the Holders of all of the Notes waive an existing Default or Event of
Default and its consequences hereunder, except a continuing Default or Event of
Default in the payment of the principal of, premium, if any, or interest on, the
Notes (including in connection with an offer to purchase) (provided, however,
that the Holders of a majority in aggregate principal amount of the then
outstanding Notes may rescind an acceleration and its consequences, including
any related payment default that resulted from such acceleration). 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
impair any right consequent thereon.

Section 6.05.     Control by Majority.

     Holders of a majority in principal amount of the then outstanding Notes may
direct the time, method and place of conducting any proceeding for exercising
any remedy available to the Trustee or exercising any trust or power conferred
on it. However, the Trustee may refuse to follow any direction that conflicts
with law or this Indenture that the Trustee determines may be unduly prejudicial
to the rights of other Holders of Notes or that may involve the Trustee in
personal liability. The Trustee may take any other action which it deems proper
that is not inconsistent with any such directive.

Section 6.06.     Limitation on Suits.

     A Holder of a Note may pursue a remedy with respect to this Indenture or
the Notes only if:

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

          (b) the Holders of at least 25% in principal amount of the then
     outstanding Notes make a written request to the Trustee to pursue the
     remedy;

          (c) such Holder of a Note or Holders of Notes offer and, if requested,
     provide to the Trustee indemnity satisfactory to the Trustee against any
     loss, liability or expense;

          (d) the Trustee does not comply with the request within 60 days after
     receipt of the request and the offer and, if requested, the provision of
     indemnity; and


<PAGE>
                                      -64-


          (e) during such 60-day period the Holders of a majority in principal
     amount of the then outstanding Notes do not give the Trustee a direction
     inconsistent with the request.

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

Section 6.07.     Rights of Holders of Notes to Receive Payment.

     Notwithstanding any other provision of this Indenture, the right of any
Holder of a Note to receive payment of principal, premium, if any, and interest
on the Note, on or after the respective due dates expressed in the Note
(including in connection with an offer to purchase), or to bring suit for the
enforcement of any such payment on or after such respective dates, shall not be
impaired or affected without the consent of such Holder.

Section 6.08.     Collection Suit by Trustee.

     If an Event of Default specified in Section 6.01(a) or (b) occurs and is
continuing, the Trustee is authorized to recover judgment in its own name and as
trustee of an express trust against the Company for the whole amount of
principal of, premium, if any, and interest remaining unpaid on the Notes and
interest on overdue principal and, to the extent lawful, interest and such
further amount as shall be sufficient to cover the costs and expenses of
collection, including the reasonable compensation, expenses, disbursements and
advances of the Trustee, its agents and counsel.

Section 6.09.     Trustee May File Proofs of Claim.

     The Trustee is authorized to 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 the
Holders of the Notes allowed in any judicial proceedings relative to the Company
(or any other obligor upon the Notes), its creditors or its property and shall
be entitled and empowered to collect, receive and distribute any money or other
property payable or deliverable on any such claims and any custodian 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 agents and counsel, and any other amounts due the Trustee under
Section 7.07 hereof. To the extent that the payment of any such compensation,
expenses, disbursements and advances of the Trustee, its agents and counsel, and
any other amounts due the Trustee under Section 7.07 hereof out of the estate in
any such proceeding, shall be denied for any reason, payment of the same shall
be secured by a Lien on, and shall be paid out of, any and all distributions,
dividends, money, securities and other properties that the Holders may be
entitled to receive in such proceeding whether in liquidation or under any plan
of reorganization or arrangement or otherwise. Nothing herein contained shall be
deemed to authorize the Trustee to authorize or consent to or accept or adopt on
behalf of any Holder any plan of reorganization, arrangement, adjustment or
composition affecting the Notes or the rights of any Holder, 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, it shall pay
out the money in the following order:


<PAGE>
                                      -65-


          First: to the Trustee, its agents and attorneys for amounts due under
     Section 7.07 hereof, including payment of all compensation, expense and
     liabilities incurred, and all advances made, by the Trustee and the costs
     and expenses of collection;

          Second: to Holders of Notes for amounts due and unpaid on the Notes
     for principal, premium, if any, and interest, ratably, without preference
     or priority of any kind, according to the amounts due and payable on the
     Notes for principal, premium, if any and interest, respectively; and

          Third: to the Company or to such party as a court of competent
     jurisdiction shall direct.

     The Trustee may fix a record date and payment date for any payment to
Holders of Notes 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 a
Trustee, a court in its discretion may require the filing by any party litigant
in the suit of an undertaking to pay the costs of the suit, and the court in its
discretion 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 does
not apply to a suit by the Trustee, a suit by a Holder of a Note pursuant to
Section 6.07 hereof, or a suit by Holders of more than 10% in principal amount
of the then outstanding Notes.

Section 6.12.     Indemnification for Judgment Currency Fluctuations.

     The obligations of the Company to any Holder of Notes shall,
notwithstanding any judgment in a currency (the "Judgment Currency") other than
U.S. dollars (the "Agreement Currency"), be discharged only to the extent that
on the day following receipt by such Holder of Notes or the Trustee, as the case
may be, of any amount in the Judgment Currency, such Holder of Notes may in
accordance with normal banking procedures purchase the Agreement Currency with
the Judgment Currency. If the amount of the Agreement Currency so purchased is
less than the amount originally to be paid to such Holder of Notes or the
Trustee, as the case may be, in the Agreement Currency, the Company shall pay
the difference and if the amount of the Agreement Currency so purchased exceeds
the amount originally to be paid to such Holder of Notes or the Trustee, as the
case may be, such Holder of Notes or the Trustee, as the case may be, shall pay
to or for the account of the Company such excess, provided that such Holder of
Notes or the Trustee, as the case may be, shall not have any obligation to pay
any such excess as long as a Default by the Company in its obligations under the
Notes or this Indenture has occurred and is continuing, in which case such
excess may be applied by such Holder of Notes to such obligations.

                                    ARTICLE 7
                                     TRUSTEE

Section 7.01.     Duties of Trustee.

     (a) If an Event of Default has occurred and is continuing, the Trustee
shall exercise such of the rights and powers vested in it by this Indenture, and
use the same degree of care and skill in its exercise, as a prudent person would
exercise or use under the circumstances in the conduct of such person's own
affairs.

     (b) Except during the continuance of an Event of Default:


<PAGE>
                                      -66-


          (i) the duties of the Trustee shall be determined solely by the
     express provisions of this Indenture and the Trustee need perform only
     those duties that are specifically set forth in this Indenture and no
     others, and no implied covenants or obligations shall be read into this
     Indenture against the Trustee; and

          (ii) in the absence of bad faith on its part, the Trustee may
     conclusively rely, as to the truth of the statements and the correctness of
     the opinions expressed therein, upon certificates or opinions furnished to
     the Trustee and conforming to the requirements of this Indenture. However,
     the Trustee shall examine the certificates and opinions to determine
     whether or not they conform to the requirements of this Indenture.

     (c) The Trustee may not be relieved from liabilities for its own negligent
action, its own negligent failure to act, or its own willful misconduct, except
that:

          (i) this paragraph does not limit the effect of paragraph (b) of this
     Section;

          (ii) the Trustee shall not be liable for any error of judgment made in
     good faith by a Responsible Officer, unless it is proved that the Trustee
     was negligent in ascertaining the pertinent facts; and

          (iii) the Trustee shall not be liable with respect to any action it
     takes or omits to take in good faith in accordance with a direction
     received by it pursuant to Section 6.05 hereof.

     (d) Whether or not therein expressly so provided, every provision of this
Indenture that in any way relates to the Trustee is subject to paragraphs (a),
(b), and (c) of this Section.

     (e) No provision of this Indenture shall require the Trustee to expend or
risk its own funds or incur any liability. The Trustee shall be under no
obligation to exercise any of its rights and powers under this Indenture at the
request of any Holders, unless such Holder shall have offered to the Trustee
security and indemnity satisfactory to it against any loss, liability or
expense.

     (f) 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.

Section 7.02.     Rights of Trustee.

     (a) The Trustee may conclusively rely upon any document believed by it to
be genuine and to have been signed or presented by the proper Person. The
Trustee need not investigate any fact or matter stated in the document.

     (b) Before the Trustee acts or refrains from acting, it may require an
Officers' Certificate or an Opinion of Counsel or both. The Trustee shall not be
liable for any action it takes or omits to take in good faith in reliance on
such Officers' Certificate or Opinion of Counsel. The Trustee may consult with
counsel and the written advice of such counsel or any Opinion of Counsel shall
be full and complete authorization and protection from liability in respect of
any action taken, suffered or omitted by it hereunder in good faith and in
reliance thereon.


<PAGE>
                                      -67-


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

     (d) 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 the rights or
powers conferred upon it by this Indenture.

     (e) Unless otherwise specifically provided in this Indenture, any demand,
request, direction or notice from the Company shall be sufficient if signed by
an Officer of the Company.

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

     (g) The Trustee shall not be charged with knowledge of any Default or Event
of Default with respect to the Notes unless either (1) a Responsible Officer of
the Trustee assigned to the Corporate Trust Office of the Trustee (or any
successor division or office) shall have actual knowledge of such Default or
Event of Default or (2) written notice of such Default or Event of Default shall
have been given to the Trustee by the Company or any other obligor on the Notes
or by any Holder of the Notes

Section 7.03.     Individual Rights of Trustee.

     The Trustee in its individual or any other capacity may become the owner or
pledgee of Notes and may otherwise deal with the Company or any Affiliate of the
Company with the same rights it would have if it were not Trustee. However, in
the event that the Trustee acquires any conflicting interest it must eliminate
such conflict within 90 days, apply to the SEC for permission to continue as
trustee or resign. Any Agent may do the same with like rights and duties. The
Trustee is also subject to Sections 7.10 and 7.11 hereof.

Section 7.04.     Trustee's Disclaimer.

     The Trustee shall not be responsible for and makes no representation as to
the validity or adequacy of this Indenture or the Notes, it shall not be
accountable for the Company's use of the proceeds from the Notes or any money
paid to the Company or upon the Company's direction under any provision of this
Indenture, it shall not be responsible for the use or application of any money
received by any Paying Agent other than the Trustee, and it shall not be
responsible for any statement or recital herein or any statement in the Notes or
any other document in connection with the sale of the Notes or pursuant to this
Indenture other than its certificate of authentication.

Section 7.05.     Notice of Defaults.

     If a Default or Event of Default occurs and is continuing and if it is
known to the Trustee, the Trustee shall mail to Holders of Notes a notice of the
Default or Event of Default within 90 days after it occurs. Except in the case
of a Default or Event of Default in payment of principal of, premium, if any, or
interest on any Note, the Trustee may withhold the notice if and so long as a
committee of its Responsible Officers in good faith determines that withholding
the notice is in the interests of the Holders of the Notes.


<PAGE>
                                      -68-


Section 7.06.     Reports by Trustee to Holders of the Notes.

     Within 60 days after each May 15 beginning with the May 15 following the
date of this Indenture, and for so long as Notes remain outstanding, the Trustee
shall mail to the Holders of the Notes a brief report dated as of such reporting
date that complies with TIA ss. 313(a) (but if no event described in TIA ss.
313(a) has occurred within the twelve months preceding the reporting date, no
report need be transmitted). The Trustee also shall comply with TIA ss.
313(b)(2). The Trustee shall also transmit by mail all reports as required by
TIA ss. 313(c).

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

Section 7.07.     Compensation and Indemnity.

     The Company shall pay to the Trustee from time to time reasonable
compensation for its acceptance of this Indenture and services hereunder. The
Trustee's compensation shall not be limited by any law on compensation of a
trustee of an express trust. The Company shall reimburse the Trustee promptly
upon request for all reasonable disbursements, advances and expenses incurred or
made by it in addition to the compensation for its services. Such expenses shall
include the reasonable compensation, disbursements and expenses of the Trustee's
agents and counsel.

     The Company shall indemnify the Trustee against any and all losses,
liabilities or expenses incurred by it arising out of or in connection with the
acceptance or administration of its duties under this Indenture, including the
costs and expenses of enforcing this Indenture against the Company (including
this Section 7.07) and defending itself against any claim (whether asserted by
the Company or any Holder or any other person) or liability in connection with
the exercise or performance of any of its powers or duties hereunder, except to
the extent any such loss, liability or expense may be attributable to its
negligence or bad faith. The Trustee shall notify the Company promptly of any
claim for which it may seek indemnity. Failure by the Trustee to so notify the
Company shall not relieve the Company of its obligations hereunder. The Company
shall defend the claim and the Trustee shall cooperate in the defense. The
Trustee may have separate counsel and the Company shall pay the reasonable fees
and expenses of such counsel. The Company need not pay for any settlement made
without its consent, which consent shall not be unreasonably withheld.

     The obligations of the Company under this Section 7.07 shall survive
resignation or removal of the Trustee and the satisfaction and discharge of this
Indenture.

     To secure the Company's payment obligations in this Section, the Trustee
shall have a Lien prior to the Notes on all money or property held or collected
by the Trustee, except that held in trust to pay principal and interest on
particular Notes. Such Lien shall survive the resignation or removal of the
Trustee and the satisfaction and discharge of this Indenture.

     When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 6.01(i) or (j) hereof occurs, the expenses and the
compensation for the services (including the fees and expenses of its agents and
counsel) are intended to constitute expenses of administration under any
Bankruptcy Law.

     The Trustee shall comply with the provisions of TIA ss. 313(b)(2) to the
extent applicable.


<PAGE>
                                      -69-


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.

     The Trustee may resign in writing at any time and be discharged from the
trust hereby created by so notifying the Company. The Holders of a majority in
principal amount of the then outstanding Notes may remove the Trustee by so
notifying the Trustee and the Company in writing. The Company may remove the
Trustee if:

          (a) the Trustee fails to comply with Section 7.10 hereof;

          (b) the Trustee is adjudged a bankrupt or an insolvent or an order for
     relief is entered with respect to the Trustee under any Bankruptcy Law;

          (c) a custodian or public officer takes charge of the Trustee or its
     property; or

          (d) 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 then outstanding Notes may appoint a
successor Trustee to replace the successor Trustee appointed by the Company.

     If a successor Trustee does not take office within 60 days after the
retiring Trustee resigns or is removed, the retiring Trustee, the Company, or
the Holders of at least 10% in principal amount of the then outstanding Notes
may petition any court of competent jurisdiction for the appointment of a
successor Trustee.

     If the Trustee, after written request by any Holder who has been a Holder
for at least six months, fails to comply with Section 7.10, such Holder may
petition any court of competent jurisdiction for the removal of the Trustee and
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. Thereupon, the resignation or
removal of the retiring Trustee shall become effective, and the successor
Trustee shall have all the rights, powers and duties of the Trustee under this
Indenture. The successor Trustee shall mail a notice of its succession to
Holders. The retiring Trustee shall promptly transfer all property held by it as
Trustee to the successor Trustee, provided all sums owing to the Trustee
hereunder have been paid and subject to the Lien provided for in Section 7.07
hereof. Notwithstanding replacement of the Trustee pursuant to this Section
7.08, the Company's obligations under Section 7.07 hereof shall continue for the
benefit of the retiring Trustee.

Section 7.09.     Successor Trustee by Merger, etc.

     If the Trustee consolidates, merges or converts into, or transfers all or
substantially all of its corporate trust business to, another corporation, the
successor corporation without any further act shall be the successor Trustee.


<PAGE>
                                      -70-


Section 7.10.     Eligibility; Disqualification.

     There shall at all times be a Trustee hereunder that is a corporation
organized and doing business under the laws of the United States of America or
of any state thereof that is authorized under such laws to exercise corporate
trustee power, that is subject to supervision or examination by federal or state
authorities and that has a combined capital and surplus of at least $100 million
as set forth in its most recent published annual report of condition.

     This Indenture shall always have a Trustee who satisfies the requirements
of TIA ss. 310(a)(1), (2) and (5). The Trustee is subject to TIA ss. 310(b).

Section 7.11.     Preferential Collection of Claims Against Company.

     The Trustee is subject to TIA ss. 311(a), excluding any creditor
relationship listed in TIA ss. 311(b). A Trustee who has resigned or been
removed shall be subject to TIA ss. 311(a) to the extent indicated therein.

                                    ARTICLE 8
                    LEGAL DEFEASANCE AND COVENANT DEFEASANCE

Section 8.01.     Option to Effect Legal Defeasance or Covenant Defeasance.

     The Company may, at the option of the Board of Directors evidenced by a
Board Resolution, at any time, elect to have either Section 8.02 or 8.03 hereof
be applied to all outstanding Notes upon compliance with the conditions set
forth below in this Article Eight.

Section 8.02.     Legal Defeasance and Discharge.

     Upon the Company's exercise under Section 8.01 hereof of the option
applicable to this Section 8.02, the Company shall, subject to the satisfaction
of the conditions set forth in Section 8.04 hereof, be deemed to have been
discharged from its obligations with respect to all outstanding Notes on the
date the conditions set forth below are satisfied (hereinafter, "Legal
Defeasance"). For this purpose, Legal Defeasance means that the Company shall be
deemed to have paid and discharged the entire Indebtedness represented by the
outstanding Notes, which shall thereafter be deemed to be "outstanding" only for
the purposes of Section 8.05 hereof and the other Sections of this Indenture
referred to in (a) and (b) below, and to have satisfied all its other
obligations under the Notes and this Indenture (and the Trustee, on demand of
and at the expense of the Company, shall execute proper instruments
acknowledging the same), except for the following provisions which shall survive
until otherwise terminated or discharged hereunder:

          (a) the rights of Holders of outstanding Notes to receive payments in
     respect of the principal of, premium, if any, and interest on the Notes
     when such payments are due from the trust referred to below;

          (b) the Company's obligations with respect to the Notes concerning
     issuing temporary Notes, registration of Notes, mutilated, destroyed, lost
     or stolen Notes and the maintenance of an office or agency for payment and
     money for security payments held in trust;

          (c) the rights, powers, trusts, duties and immunities of the Trustee,
     and the Company's obligations in connection therewith;


<PAGE>
                                      -71-


          (d) the Legal Defeasance provisions of this Indenture; and

          (e) the Company's obligation to pay Additional Amounts.

     Subject to compliance with this Article Eight, the Company may exercise its
option under this Section 8.02 notwithstanding the prior exercise of its option
under Section 8.03 hereof.

Section 8.03.     Covenant Defeasance.

     Upon the Company's exercise under Section 8.01 hereof of the option
applicable to this Section 8.03, the Company shall, subject to the satisfaction
of the conditions set forth in Section 8.04 hereof, be released from its
obligations under the covenants contained in Article 5 and Sections 4.03, 4.07,
4.08, 4.09, 4.10, 4.11, 4.12, 4.14, 4.15 and 4.16 hereof with respect to the
outstanding Notes on and after the date the conditions set forth in Section 8.04
are satisfied (hereinafter, "Covenant Defeasance"), and the Notes shall
thereafter be deemed not "outstanding" for the purposes of any direction,
waiver, consent or declaration or act of Holders (and the consequences of any
thereof) in connection with such covenants, but shall continue to be deemed
"outstanding" for all other purposes hereunder (it being understood that such
Notes shall not be deemed outstanding for accounting purposes). For this
purpose, Covenant Defeasance means that, with respect to the outstanding Notes,
the Company may omit to comply with and shall have no liability in respect of
any term, condition or limitation set forth in any such covenant, whether
directly or indirectly, by reason of any reference elsewhere herein to any such
covenant or by reason of any reference in any such covenant to any other
provision herein or in any other document and such omission to comply shall not
constitute a Default or an Event of Default under Section 6.01 hereof, but,
except as specified above, the remainder of this Indenture and such Notes shall
be unaffected thereby. In addition, upon the Company's exercise under Section
8.01 hereof of the option applicable to this Section 8.03 hereof, subject to the
satisfaction of the conditions set forth in Section 8.04 hereof, Sections
6.01(c) through 6.01(e) hereof and Section 6.01(g) hereof shall not constitute
Events of Default.

Section 8.04.     Conditions to Legal or Covenant Defeasance.

     The following shall be the conditions to the application of either Section
8.02 or 8.03 hereof to the outstanding Notes:

     In order to exercise either Legal Defeasance or Covenant Defeasance:

          (a) the Company must irrevocably deposit with the Trustee, in trust,
     for the benefit of the Holders of the Notes, cash in U.S. dollars,
     non-callable Government Securities, or a combination thereof in such
     amounts as shall be sufficient, in the opinion of a nationally recognized
     firm of independent public accountants, to pay the principal of, premium,
     if any, and interest on the outstanding Notes on the stated maturity or on
     the applicable redemption date, as the case may be, and the Company must
     specify whether the Notes are being defeased to maturity or to a particular
     redemption date;

          (b) in the case of an election under Section 8.02 hereof, the Company
     shall have delivered to the Trustee an Opinion of Counsel reasonably
     acceptable to the Trustee confirming that (a) the Company has received
     from, or there has been published by, the Internal Revenue Service a ruling
     or (b) since the Issue Date, there has been a change in the applicable
     federal income tax law, in either case to the effect that, and based
     thereon such Opinion of Counsel shall confirm that, the Holders of the
     outstanding Notes shall not recognize income, gain or loss for United
     States federal income tax purposes as a result of such Legal Defeasance and
     shall be subject to United States federal income tax on the same amounts,
     in the same manner and at the same times as would have been the case if
     such Legal Defea-


<PAGE>
                                      -72-


     sance had not occurred and the Company shall have delivered to the Trustee
     an Opinion of Counsel in Canada reasonably acceptable to the Trustee
     confirming that the Holders of the outstanding Notes shall not recognize
     income, gain or loss for Canadian federal income tax purposes as a result
     of such Legal Defeasance and shall be subject to Canadian federal income
     tax on the same amounts, in the same manner and at the same times as would
     have been the case if such Legal Defeasance had not occurred;

          (c) in the case of an election under Section 8.03 hereof, the Company
     shall have delivered to the Trustee an Opinion of Counsel reasonably
     acceptable to the Trustee confirming that the Holders of the outstanding
     Notes shall not recognize income, gain or loss for United States federal
     income tax purposes as a result of such Covenant Defeasance and shall be
     subject to United States federal income tax on the same amounts, in the
     same manner and at the same times as would have been the case if such
     Covenant Defeasance had not occurred and the Company shall have delivered
     to the Trustee an Opinion of Counsel in Canada reasonably acceptable to the
     Trustee confirming that the Holders of the outstanding Notes shall not
     recognize income, gain or loss for Canadian federal income tax purposes as
     a result of such Covenant Defeasance and shall be subject to Canadian
     federal income tax on the same amounts, in the same manner and at the same
     times as would have been the case if such Covenant Defeasance had not
     occurred;

          (d) no Default or Event of Default shall have occurred and be
     continuing on the date of such deposit (other than a Default or Event of
     Default resulting from the borrowing of funds to be applied to such
     deposit);

          (e) such Legal Defeasance or Covenant Defeasance shall not result in a
     breach or violation of, or constitute a default under, any material
     agreement or instrument (other than this Indenture) to which the Company or
     any of its Restricted Subsidiaries is a party or by which the Company or
     any of its Restricted Subsidiaries is bound;

          (f) the Company shall have delivered to the Trustee an Officers'
     Certificate stating that the deposit was not made by the Company with the
     intent of preferring the Holders over any other creditors of the Company or
     with the intent of defeating, hindering, delaying or defrauding creditors
     of the Company or others; and

          (g) the Company shall have delivered to the Trustee an Officers'
     Certificate and an Opinion of counsel, in the case of the Officers'
     Certificate, stating that all conditions precedent relating to the Legal
     Defeasance or the Covenant Defeasance have been complied with and, in the
     case of the Opinion of Counsel, that the conditions precedent in clauses
     (a) (with respect to the validity and perfection of the security interest),
     (b), (c) and (e) have been complied with and that the trust referred to in
     clause (a) will not be required to register under the Investment Company
     Act of 1940.

Section 8.05. Deposited Money and Government Securities to be Held in Trust;
              Other Miscellaneous Provisions.

     Subject to Section 8.06 hereof, all money and non-callable Government
Securities (including the proceeds thereof) deposited with the Trustee (or other
qualifying trustee, collectively for purposes of this Section 8.05, the
"Trustee") pursuant to Section 8.04 hereof in respect of the outstanding Notes
shall be held in trust and applied by the Trustee, in accordance with the
provisions of such Notes and this Indenture, to the payment, either directly or
through any Paying Agent (including the Company acting as Paying Agent) as the
Trustee may determine, to the Holders of the Notes of all sums due and to become
due thereon in respect of principal, premium, if any, and interest, but such
money need not be segregated from other funds except to the extent required by
law.


<PAGE>
                                      -73-


     The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the cash or non-callable Government
Securities deposited pursuant to Section 8.04 hereof or the principal and
interest received in respect thereof other than any such tax, fee or other
charge which by law is for the account of the Holders of the outstanding Notes.

     Anything in this Article Eight to the contrary notwithstanding, the Trustee
shall deliver or pay to the Company from time to time upon the request of the
Company any money or non-callable Government Securities held by it as provided
in Section 8.04 hereof which, in the opinion of a nationally recognized firm of
independent public accountants expressed in a written certification thereof
delivered to the Trustee (which may be the opinion delivered under Section
8.04(a) hereof), are in excess of the amount thereof that would then be required
to be deposited to effect an equivalent Legal Defeasance or Covenant Defeasance.

Section 8.06.     Repayment to Company.

     Any money deposited with the Trustee or any Paying Agent, or then held by
the Company, in trust for the payment of the principal of, premium, if any, or
interest on any Note and remaining unclaimed for two years after such principal,
and premium, if any, or interest has become due and payable shall be paid to the
Company on its request or (if then held by the Company) shall be discharged from
such trust; and the Holder of such Note shall thereafter look only to the
Company for payment thereof, and all liability of the Trustee or such Paying
Agent with respect to such trust money, and all liability of the Company as
trustee thereof, shall thereupon cease; provided, however, that the Trustee or
such Paying Agent, before being required to make any such repayment, may at the
expense of the Company cause to be published once, in the New York Times and The
Wall Street Journal (national edition), notice that such money remains unclaimed
and that, after a date specified therein, which shall not be less than 30 days
from the date of such notification or publication, any unclaimed balance of such
money then remaining shall be repaid to the Company.

Section 8.07.     Reinstatement.

     If the Trustee or Paying Agent is unable to apply any United States dollars
or non-callable Government Securities in accordance with Section 8.02 or 8.03
hereof, as the case may be, by reason of any order or judgment of any court or
governmental authority enjoining, restraining or otherwise prohibiting such
application, then the Company's obligations under this Indenture and the Notes
shall be revived and reinstated as though no deposit had occurred pursuant to
Section 8.02 or 8.03 hereof until such time as the Trustee or Paying Agent is
permitted to apply all such money in accordance with Section 8.02 or 8.03
hereof, as the case may be; provided, however, that, if the Company makes any
payment of principal of, premium, if any, or interest on any Note following the
reinstatement of its obligations, the Company shall be subrogated to the rights
of the Holders of the Notes to receive such payment from the money held by the
Trustee or Paying Agent.

                                    ARTICLE 9
                        AMENDMENT, SUPPLEMENT AND WAIVER

Section 9.01.     Without Consent of Holders of Notes.

     Notwithstanding Section 9.02 of this Indenture, the Company and the Trustee
may amend or supplement this Indenture or the Notes without the consent of any
Holder of a Note:

          (a) to cure any ambiguity, defect or inconsistency;

          (b) to provide for uncertificated Notes in addition to or in place of
     certificated Notes;


<PAGE>
                                      -74-


          (c) to provide for the assumption of the Company's obligations to
     Holders of Notes in the case of a merger or consolidation or sale of all or
     substantially all of the Company's assets pursuant to Article 5 hereof;

          (d) to make any change that would provide any additional rights or
     benefits to the Holders of Notes or that does not adversely affect the
     legal rights under this Indenture of any such Holder; or

          (e) to comply with requirements of the SEC in order to effect or
     maintain the qualification of this Indenture under the TIA.

     Upon the request of the Company accompanied by a Board Resolution
authorizing the execution of any such amended or supplemental Indenture, and
upon receipt by the Trustee of the documents described in Section 7.02 hereof,
the Trustee shall join with the Company in the execution of any amended or
supplemental Indenture authorized or permitted by the terms of this Indenture
and to make any further appropriate agreements and stipulations that may be
therein contained, but the Trustee shall not be obligated to enter into such
amended or supplemental Indenture that affects its own rights, duties or
immunities under this Indenture or otherwise.

Section 9.02.     With Consent of Holders of Notes.

     Except as provided below in this Section 9.02, the Company and the Trustee
may amend or supplement this Indenture (including Section 3.09, 4.10 and 4.14
hereof) and 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
voting as a single class (including consents obtained in connection with a
tender offer or exchange offer for, or purchase of, the Notes), and, subject to
Sections 6.04 and 6.07 hereof, any existing Default or Event of Default (other
than a Default or Event of Default in the payment of the principal of, premium,
if any, or interest on the Notes, except a payment default resulting from an
acceleration that has been rescinded) or compliance with any provision of this
Indenture or the Notes may be waived with the consent of the Holders of a
majority in principal amount of the then outstanding Notes voting as a single
class (including consents obtained in connection with a tender offer or exchange
offer for, or purchase of, the Notes). Section 2.08 hereof shall determine which
Notes are considered to be "outstanding" for purposes of this Section 9.02.

     Upon the request of the Company accompanied by a Board Resolution
authorizing the execution of any such amended or supplemental Indenture, and
upon the filing with the Trustee of evidence satisfactory to the Trustee of the
consent of the Holders of Notes as aforesaid, and upon receipt by the Trustee of
the documents described in Section 7.02 hereof, the Trustee shall join with the
Company in the execution of such amended or supplemental Indenture unless such
amended or supplemental Indenture directly affects the Trustee's own rights,
duties or immunities under this Indenture or otherwise, in which case the
Trustee may in its discretion, but shall not be obligated to, enter into such
amended or supplemental Indenture.

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

     After an amendment, supplement or waiver under this Section becomes
effective, the Company shall mail to the Holders of Notes affected thereby a
notice briefly describing the amendment, supplement or waiver. 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 amended or supplemental
Indenture or waiver. Subject to Sections 6.04 and 6.07 hereof, the Holders of a
majority in aggregate principal amount of the Notes then outstanding may waive
compliance in a particular instance by the Company with any provision of this
Indenture or the Notes. However, with-


<PAGE>
                                      -75-


out the consent of each Holder affected, an amendment or waiver under this
Section 9.02 may not (with respect to any Notes held by a non-consenting
Holder):

          (a) reduce the principal amount of Notes whose Holders must consent to
     an amendment, supplement or waiver;

          (b) reduce the principal of or change the fixed maturity of any Note
     or alter or waive any of the provisions with respect to the redemption of
     such Note (except as provided above with respect to Sections 4.10 and 4.14
     hereof);

          (c) reduce the rate of or change the time for payment of interest on
     any Note;

          (d) waive a Default or Event of Default in the payment of principal of
     or premium, if any, or interest on the Notes (except a rescission of
     acceleration of such Notes by the Holders of at least a majority in
     aggregate principal amount of the then outstanding Notes and a waiver of
     the payment default that resulted from such acceleration);

          (e) make any Note payable in money other than that stated in the
     Notes;

          (f) make any change in the provisions of this Indenture relating to
     waivers of past Defaults or the rights of Holders of the Notes to receive
     payments of principal of or premium, if any, or interest on the Notes;

          (g) waive a redemption payment with respect to any Note (other than a
     payment required by one of the covenants described in Sections 4.10 and
     4.14)

          (h) cause the Notes to become subordinate in right of payment to any
     other Indebtedness or to otherwise reduce the ranking of the Notes;

          (i) make any change that would adversely affect the rights of the
     Holders to receive Additional Amounts;

          (j) modify the obligation of the Company to make a Change of Control
     Offer to purchase Notes after the occurrence of an event which constitutes
     a Change of Control; or

          (k) make any change in the preceding amendment and waiver provisions.

Section 9.03.     Compliance with Trust Indenture Act.

     Every amendment or supplement to this Indenture or the Notes shall be set
forth in a amended or supplemental Indenture that complies with the TIA as then
in effect.

Section 9.04.     Revocation and Effect of Consents.

     Until an amendment, supplement or waiver becomes effective, a consent to it
by a Holder of a Note is a continuing consent by the Holder of such Note and
every subsequent Holder of such Note or portion of such Note that evidences the
same debt as the consenting Holder's Note, even if notation of the consent is
not made on any Note. However, any such Holder of a Note or subsequent Holder of
a Note may revoke the consent as to its Note if the Trustee receives written
notice of revocation before the date the waiver, supplement or amendment be-


<PAGE>
                                      -76-


comes effective. An amendment, supplement or waiver becomes effective in
accordance with its terms and thereafter binds every Holder.

Section 9.05.     Notation on or Exchange of Notes.

     The Trustee may place an appropriate notation about an amendment,
supplement or waiver on any Note thereafter authenticated. The Company in
exchange for all Notes may issue and the Trustee shall, upon receipt of an
Authentication Order, authenticate new Notes that reflect the amendment,
supplement or waiver.

     Failure to make the appropriate notation or issue a new Note shall not
affect the validity and effect of such amendment, supplement or waiver.

Section 9.06.     Trustee to Sign Amendments, etc.

     The Trustee shall sign any amended or supplemental Indenture authorized
pursuant to this Article Nine if the amendment or supplement does not adversely
affect the rights, duties, liabilities or immunities of the Trustee. The Company
may not sign an amendment or supplemental Indenture until the Board of Directors
approves it. In executing any amended or supplemental indenture, the Trustee
shall be entitled to receive and (subject to Section 7.01 hereof) shall be fully
protected in relying upon, in addition to the documents required by Section
10.04 hereof, an Officer's Certificate and an Opinion of Counsel stating that
the execution of such amended or supplemental indenture is authorized or
permitted by this Indenture.

                                   ARTICLE 9A
                             SATISFACTION AND WAIVER

Section 9.01A     Satisfaction and Discharge of Indenture

     This Indenture shall be discharged and shall cease to be of further effect
as to all Notes issued hereunder, when either (a) all Notes theretofore
authenticated and delivered (except lost, stolen or destroyed Notes which have
been replaced or paid and Notes for whose payment money has theretofore been
deposited in trust and thereafter repaid to the Company) have been delivered to
the Trustee for cancellation; or (b)(i) all Notes not theretofore delivered to
the Trustee for cancellation have become due and payable by reason of the making
of a notice of redemption or otherwise or will become due and payable within one
year and the Company has irrevocably deposited or caused to be deposited with
the Trustee as trust funds in trust an amount of money sufficient to pay and
discharge the entire Indebtedness on Notes not theretofore delivered to the
Trustee for cancellation for principal, premium, if any, and accrued interest to
the date of maturity or redemption; (ii) no Default or Event of Default with
respect to this Indenture or the Notes shall have occurred and be continuing on
the date of such deposit or shall occur as a result of such deposit and such
deposit shall not result in a breach or violation of, or constitute a default
under, any other instrument to which the Company is a party or by which the
Company or a Subsidiary Guarantor, if any, is bound: (iii) the Company has paid
or caused to be paid all sums payable by it under this Indenture; and (iv) the
Company has delivered irrevocable instructions to the Trustee under this
Indenture to apply the deposited money toward the payment of the Notes at
maturity or the redemption date, as the case may be.

     In addition, the Company shall deliver an Officer's Certificate and an
Opinion of Counsel to the Trustee stating that all conditions precedent to the
satisfaction and discharge of this Indenture have been satisfied.


<PAGE>
                                      -77-


Section 9.02A     Application of Trust Money

     All money deposited with the Trustee pursuant to Section 9.01A shall be
held in trust and applied by it, in accordance with the provisions of the Notes
and this Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as Paying Agent) as the Trustee may determine, to
Persons entitled thereto, of the principal (and premium, if any) and interest
for whose payment such money has been deposited with the Trustee.

     If the Trustee or Paying Agent is unable to apply any money in accordance
with Section 9.01A by reason of any legal proceeding or by reason of any order
or judgement of any court or governmental authority enjoining, restraining or
otherwise prohibiting such application, the Company's obligations under this
Indenture and the Notes shall be revived and reinstated as though such deposit
had not occurred pursuant to Section 9.01A; provided that if the Company has
made any payment of principal of, premium, if any, or interest on any Notes
because of the reinstatement of its obligations, the money shall be subrogated
to the rights of the Holders of such Notes to receive such payment from the
Company or money held by the Trustee or Paying Agent.

                                   ARTICLE 10
                                  MISCELLANEOUS

Section 10.01.    Trust Indenture Act Controls.

     If any provision of this Indenture limits, qualifies or conflicts with the
duties imposed by TIA ss. 318(c), the imposed duties shall control.

Section 10.02.    Notices.

     Any notice or communication by the Company or the Trustee to the others is
duly given if in writing and delivered in Person or mailed by first class mail
(registered or certified, return receipt requested), telex, telecopier or
overnight air courier guaranteeing next day delivery, to the others' address:

                  If to the Company:  360networks inc.
                                      1510-1066 West Hastings Street
                                      Vancouver, BC Canada V6E 3X1
                                      Telecopier No.: (604) 681-6822
                                      Attention:  Secretary

                  With a copy to:     Cahill Gordon & Reindel
                                      80 Pine Street
                                      New York, New York 10005
                                      Telecopier No.: (212)701-3000
                                      Attention: Roger Andrus, Esq.

                  If to the Trustee:  HSBC Bank USA
                                      140 Broadway, 12th Floor
                                      New York, New York 10005-1180
                                      Telecopier No.: (212) 658-6425
                                      Attention: Issuer Services


<PAGE>
                                      -78-


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

     All notices and communications (other than those sent to Holders) shall be
deemed to have been duly given: at the time delivered by hand, if personally
delivered; five Business Days after being deposited in the mail, postage
prepaid, if mailed; when answered back, if telexed; when receipt acknowledged,
if telecopied; and the next Business Day after timely delivery to the courier,
if sent by overnight air courier guaranteeing next day delivery.

     Any notice or communication to a Holder shall be mailed by first class
mail, certified or registered, return receipt requested, or by overnight air
courier guaranteeing next day delivery to its address shown on the register kept
by the Registrar. Any notice or communication shall also be so mailed to any
Person described in TIA ss. 313(c), to the extent required by the TIA. 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.

     If a notice or communication is mailed in the manner provided above within
the time prescribed, it is duly given, whether or not the addressee receives it.

     If the Company mails a notice or communication to Holders, it shall mail a
copy to the Trustee and each Agent at the same time.

Section 10.03.    Communication by Holders of Notes with Other Holders of Notes.

     Holders may communicate pursuant to TIA ss. 312(b) with other Holders with
respect to their rights under this Indenture or the Notes. The Company, the
Trustee, the Registrar and anyone else shall have the protection of TIA ss.
312(c).

Section 10.04.    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:

          (a) an Officers' Certificate in form and substance reasonably
     satisfactory to the Trustee (which shall include the statements set forth
     in Section 10.05 hereof) stating that, in the opinion of the signers, all
     conditions precedent and covenants, if any, provided for in this Indenture
     relating to the proposed action have been satisfied; and

          (b) an Opinion of Counsel in form and substance reasonably
     satisfactory to the Trustee (which shall include the statements set forth
     in Section 10.05 hereof) stating that, in the opinion of such counsel, all
     such conditions precedent and covenants have been satisfied.

Section 10.05.    Statements Required in Certificate or Opinion.

     Each certificate or opinion with respect to compliance with a condition or
covenant provided for in this Indenture (other than a certificate provided
pursuant to TIA ss. 314(a)(4)) shall comply with the provisions of TIA ss.
314(e) and shall include:

          (a) a statement that the Person making such certificate or opinion has
     read such covenant or condition;


<PAGE>
                                      -79-


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

          (c) a statement that, in the opinion of such Person, he or she 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 satisfied; and

          (d) a statement as to whether or not, in the opinion of such Person,
     such condition or covenant has been satisfied.

Section 10.06.    Rules by Trustee and Agents.

     The Trustee may make reasonable rules for action by or at a meeting of
Holders. The Registrar or Paying Agent may make reasonable rules and set
reasonable requirements for its functions.

Section 10.07. No Personal Liability of Directors, Officers, Employees and
               Stockholders.

     No past, present or future director, officer, employee, incorporator or
stockholder of the Company or any of its Subsidiaries as such, shall have any
liability for any obligations of the Company or its Subsidiaries under the
Notes, this Indenture or for any claim based on, in respect of, or by reason of,
such obligations or their creation. Each Holder by accepting a Note waives and
releases all such liability. The waiver and release are part of the
consideration for issuance of the Notes.

Section 10.08.    Governing Law.

     THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO
CONSTRUE THIS INDENTURE, THE NOTES WITHOUT GIVING EFFECT TO APPLICABLE
PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF
ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

Section 10.09.    Jurisdiction.

     To the fullest extent permitted by applicable law, the Company irrevocably
submits to the jurisdiction of any federal or state court in the City, County
and State of New York, United States of America, in any suit or proceeding based
on or arising under this Indenture (solely in connection with any such suit or
proceeding), and irrevocably agrees that all claims in respect of such suit or
proceeding may be determined in any such court. The Company irrevocably and
fully waives the defense of an inconvenient forum to the maintenance of such
suit or proceeding. The Company hereby irrevocably designates and appoints CT
Corporation System (the "Process Agent"), as the authorized agent of the Company
upon whom process may be served in any such suit or proceeding, it being
understood that the designation and appointment of CT Corporation System as such
authorized agent shall become effective immediately without any further action
on the part of the Company. The Company represents that it has notified the
Process Agent of such designation and appointment and that the Process Agent has
accepted the same in writing. The Company hereby irrevocably authorizes and
directs the Process Agent to accept such service. The Company further agrees
that service of process upon the Process Agent and written notice of said
service to the Company mailed by prepaid registered first class mail or
delivered to the Process Agent at its principal office, shall be deemed in every
respect effective service of process upon the Company in any such suit or
proceeding. Nothing herein shall affect the right of any Holder or any Person
controlling such Holder to serve process in any other manner permitted by law.
The Company further agrees to take any and all action, including the execution
and filing of any and all such documents and instruments as may be necessary to
continue


<PAGE>
                                      -80-


such designation and appointment of the Process Agent in full force and effect
so long as the Company has any outstanding obligations under this Agreement. To
the extent that the Company has or hereafter may acquire any immunity from
jurisdiction of any court or from any legal process (whether through service of
note, attachment prior to judgment, attachment in aid of execution, executor or
otherwise) with respect to itself or its property, the Company hereby
irrevocably waives such immunity in respect of their obligations under this
Indenture, to the extent permitted by law.

Section 10.10.    No Adverse Interpretation of Other Agreements.

     This Indenture may not be used to interpret any other indenture, loan or
debt agreement of the Company or its Subsidiaries or of any other Person. Any
such indenture, loan or debt agreement may not be used to interpret this
Indenture.

Section 10.11.    Successors.

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

Section 10.12.    Severability.

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

Section 10.13.    Counterpart 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 10.14.    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 of this Indenture and shall in no way
modify or restrict any of the terms or provisions hereof.

                         [Signatures on following page]





<PAGE>
                                      -81-




                                   SIGNATURES


Dated as of April 26, 2000

                                      360networks inc.


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


                                      HSBC BANK USA, AS TRUSTEE


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





<PAGE>


                                                                       EXHIBIT A


                                 [Face of Note]


                                                      CUSIP/NO. ________/_______

                            13% Senior Notes due 2008


No. ___                                                       $_________________

                                360networks inc.


promises to pay to______________________________________________________________

or registered assigns,__________________________________________________________

the principal sum of____________________________________________________________

Dollars ($_______________) on May 1, 2008.

Interest Payment Dates: May 1 and November 1

Record Dates: April 15 and October 15

Subject to Restrictions set forth in this Note.




<PAGE>
                                      -2-

Dated:

                                      360networks inc.


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


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


This is one of the Notes referred to
in the within-mentioned Indenture:

HSBC Bank USA,
     as Trustee

By:______________________________________
           Authorized Signatory




<PAGE>
                                      -3-


                                 [Back of Note]
                            13% Senior Notes due 2008

["THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE
GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL
OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES
EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY BE REQUIRED
PURSUANT TO SECTION 2.07 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE
EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.06(a) OF THE INDENTURE,
(III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT
TO SECTION 2.11 OF THE INDENTURE."](1)

["THIS NOTE (OR ITS PREDECESSOR) HAS NOT BEEN REGISTERED UNDER THE U.S.
SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT") AND, ACCORDINGLY, MAY
NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE TRANSFERRED WITHIN THE UNITED STATES
OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, U.S. PERSONS, EXCEPT AS SET FORTH IN
THE NEXT SENTENCE. BY ITS ACQUISITION HEREOF OR OF A BENEFICIAL INTEREST HEREIN,
THE HOLDER: (1) REPRESENTS THAT (A) IT IS A "QUALIFIED INSTITUTIONAL BUYER" (AS
DEFINED IN RULE 144A UNDER THE SECURITIES ACT) (A "QIB"), (B) IT HAS ACQUIRED
THIS NOTE IN AN OFFSHORE TRANSACTION IN COMPLIANCE WITH REGULATION S UNDER THE
SECURITIES ACT OR (C) 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
"IAI"), (2) AGREES THAT IT WILL NOT RESELL OR OTHERWISE TRANSFER THE NOTE EXCEPT
(A) TO THE COMPANY OR ANY OF ITS SUBSIDIARIES, (B) TO A PERSON WHOM THE SELLER
REASONABLY BELIEVES IS A QIB PURCHASING FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT
OF A QIB IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144A, (C) IN AN
OFFSHORE TRANSACTION MEETING THE REQUIREMENTS OF RULE 903 OR 904 OF THE
SECURITIES ACT, (D) IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144 UNDER
THE SECURITIES ACT, (E) TO AN IAI THAT, PRIOR TO SUCH TRANSFER, FURNISHES THE
TRUSTEE A SIGNED LETTER CONTAINING CERTAIN REPRESENTATIONS AND AGREEMENTS
RELATING TO THE TRANSFER OF THIS NOTE (THE FORM OF WHICH CAN BE OBTAINED FROM
THE TRUSTEE) AND , IF SUCH TRANSFER IS IN RESPECT OF AN AGGREGATE PRINCIPAL
AMOUNT OF NOTES LESS THAN $250,000, AN OPINION OF COUNSEL ACCEPTABLE TO THE
COMPANY THAT SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT, (F) IN
ACCORDANCE WITH ANOTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE
SECURITIES ACT (AND BASED UPON AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY)
OR (G) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT AND, IN EACH CASE, IN
ACCORDANCE WITH OTHER APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED
STATES OR ANY OTHER APPLICABLE JURISDICTION AND (3) AGREES THAT IT WILL DELIVER
TO EACH PERSON TO WHOM THIS NOTE OR AN INTEREST HEREIN IS TRANSFERRED A NOTICE
SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND. AS USED HEREIN, THE TERMS "OFFSHORE
TRANSACTION" AND "UNITED STATES" HAVE THE MEANINGS GIVEN TO THEM BY RULE 902 OF
REGULATION S UNDER THE SECURITIES ACT. THE INDENTURE CONTAINS A

----------

1    This paragraph should be included only if the Note is issued in global
     form.


<PAGE>
                                      -4-


PROVISION REQUIRING THE TRUSTEE TO REFUSE TO REGISTER ANY TRANSFER OF THIS NOTE
IN VIOLATION OF THE FOREGOING."](2)

----------

2    This paragraph should be removed upon the exchange of Notes for Exchange
     Notes in the Exchange Offer or upon the registration of the Notes pursuant
     to the terms of the Registration Rights Agreement.





<PAGE>
                                      -5-


     Capitalized terms used herein shall have the meanings assigned to them in
the Indenture referred to below unless otherwise indicated.

     1. INTEREST. 360networks inc., a company continued under the laws of Nova
Scotia, Canada (the "Company"), promises to pay interest on the principal amount
of this Note at the rate of 13% per annum from April 26, 2000 until maturity.
The interest rate on the Notes is subject to increase pursuant to the provisions
of the Registration Rights Agreement. The Company will pay interest
semi-annually in arrears on May 1 and November 1 of each year (each an "Interest
Payment Date"), or if any such day is not a Business Day, on the next succeeding
Business Day. 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 the date of
issuance; provided that if there is no existing Default in the payment of
interest, and if this Note is authenticated between a record date referred to on
the face hereof and the next succeeding Interest Payment Date, interest shall
accrue from such next succeeding Interest Payment Date; provided, further, that
the first Interest Payment Date shall be November 1, 2000. The Company shall pay
interest (including post-petition interest in any proceeding under any
Bankruptcy Law) on overdue principal and premium, if any, from time to time on
demand at a rate that is 1% per annum in excess of the rate then in effect; it
shall pay interest (including post-petition interest in any proceeding under any
Bankruptcy Law) on overdue installments of interest (without regard to any
applicable grace periods) from time to time on demand at the same rate to the
extent lawful. Interest will be computed on the basis of a 360-day year of
twelve 30-day months.

     2. METHOD OF PAYMENT. The Company will pay interest on the Notes (except
defaulted interest) to the Persons who are registered Holders of Notes at the
close of business on the April 15 or October 15 next preceding the Interest
Payment Date, even if such Notes are canceled after such record date and on or
before such Interest Payment Date, except as provided in Section 2.12 of the
Indenture with respect to defaulted interest. The Notes will be payable as to
principal, premium, if any, and interest at the office of the Paying Agent in
New York City or, subject to any applicable laws and regulations, at the office
of the Paying Agent in Luxembourg. Payment by wire transfer of immediately
available funds will be required with respect to principal of and interest,
premium on, all Notes. Such payment shall be in such coin or currency of the
United States of America as at the time of payment is legal tender for payment
of public and private debts.

     3. PAYING AGENT AND REGISTRAR. Initially, HSBC Bank USA, the Trustee under
the Indenture, will act as principal Paying Agent and Registrar and Banque
General du Luxembourg will initially act as an additional Paying Agent in
Luxembourg. The Company may change any Paying Agent or Registrar without notice
to any Holder. The Company or any of its Subsidiaries may act in any such
capacity.

     4. INDENTURE. The Company issued the Notes under an Indenture dated as of
April 26, 2000 ("Indenture") between the Company and the Trustee. 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 of 1939, as amended (15 U.S.
Code ss.ss. 77aaa-77bbbb). The Notes are subject to all such terms, and Holders
are referred to the Indenture and such Act for a statement of such terms. To the
extent any provision of this Note conflicts with the express provisions of the
Indenture, the provisions of the Indenture shall govern and be controlling. The
Notes are obligations of the Company limited to $600 million in aggregate
principal amount.

     5. OPTIONAL REDEMPTION.

     The Company may redeem the Notes in the event the Company becomes obligated
to pay any Additional Amounts as a result of a change in the laws or regulations
of Canada or any Canadian Taxing Authority, or a change in any official position
regarding the application or interpretation thereof, which is publicly announced
or becomes effective on or after the Issue Date. Upon the occurrence of any such
change, the Company may, at any time, redeem all, but not part, of the Notes at
a price equal to 100% of the principal amount thereof, plus


<PAGE>
                                       -6-


accrued and unpaid interest, if any, to the redemption date. The Company will
give written notice of any such redemption not less than 30 nor more than 60
days prior to the redemption date.

     6. PAYMENT OF ADDITIONAL AMOUNTS.

     All payments made by or on behalf of the Company on or with respect to the
Notes shall be made without withholding or deduction for any Taxes imposed by
any Canadian Taxing Authority, unless required by law or the interpretation or
administration thereof by the relevant Taxing Authority. If the Company or any
other payor is required to withhold or deduct any amount on account of Taxes
from any payment made on or with respect to the Notes, the Company shall:

          (a) make such withholding or deduction;

          (b) remit the full amount deducted or withheld to the relevant
     government authority in accordance with applicable law;

          (c) pay such additional amounts ("Additional Amounts") as may be
     necessary so that the net amount received by each Holder (including
     Additional Amounts) after such withholding or deduction shall not be less
     than the amount the Holder would have received if such Taxes had not been
     withheld or deducted;

          (d) furnish to the Holders, within 30 days after the date the payment
     of any Taxes is due, certified copies of tax receipts evidencing such
     payment by the Company;

          (e) indemnify and hold harmless each Holder (other than an Excluded
     Holder) for the amount of (i) any Taxes paid by such Holder as a result of
     payments made on or with respect to the Notes, (ii) any liability
     (including penalties, interest and expenses) arising therefrom or with
     respect thereto and (iii) any Taxes imposed with respect to any
     reimbursement under (i) or (ii), but excluding any such Taxes on such
     Holder's net income; and

          (f) at least 30 days prior to each date on which any Additional
     Amounts are payable, deliver to the Trustee an Officers' Certificate
     stating the amounts so payable and such other information necessary to
     enable the Trustee to pay such Additional Amounts to Holders on the payment
     date.

     Notwithstanding the foregoing, no Additional Amounts shall be payable to a
Holder in respect of a beneficial owner of a Note (an "Excluded Holder"):

          (a) with which the Company does not deal at arm's length (within the
     meaning of the Income Tax Act (Canada)) at the time of making such payment;
     or

          (b) which is subject to such Taxes by reason of its being connected
     with Canada or any province or territory thereof otherwise than by the mere
     acquisition, holding or disposition of Notes or the receipt of payments
     thereunder.

     7. MANDATORY REDEMPTION.

     Except as otherwise provided in Paragraph 8 below, the Company shall not be
required to make mandatory redemption payments with respect to the Notes. In
addition, the Company is not required to make any sinking fund payments with
respect to the Notes.


<PAGE>
                                       -7-


     8. REPURCHASE AT OPTION OF HOLDER.

     (a) Upon the occurrence of a Change of Control, each Holder of Notes shall
have the right to require the Company to repurchase all or any part (equal to
$1,000 or an integral multiple thereof) of that Holder's Notes pursuant to the
Change of Control Offer. In the Change of Control Offer, the Company will offer
(the "Change of Control Offer") a Change of Control Payment in cash equal to
101% of the aggregate principal amount of Notes repurchased plus accrued and
unpaid interest, if any, thereon to the date of purchase. Within 20 days
following any Change of Control, the Company will mail a notice to each Holder
(with a copy to the Trustee) describing the transaction or transactions that
constitute the Change of Control and offering to repurchase Notes on the Change
of Control Payment Date specified in such notice, pursuant to the procedures
required by the Indenture and described in such notice. The Company will comply
with the requirements of 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 connection with the repurchase of the Notes as a
result of a Change of Control.

     (b) If the Company or a Subsidiary consummates any Asset Sale, within five
days of each date on which the aggregate amount of Excess Proceeds exceeds $10
million, the Company shall commence an offer to all Holders of Notes (an "Asset
Sale Offer") pursuant to Section 3.09 of the Indenture to purchase the maximum
principal amount of Notes and pari passu Indebtedness, including the Euro Notes,
that may be purchased out of the Excess Proceeds at an offer price in cash in an
amount equal to 100% of the principal amount thereof plus accrued and unpaid
interest thereon, if any, to the date fixed for the closing of such offer, in
accordance with the procedures set forth in the Indenture. To the extent that
the aggregate amount of Notes and such pari passu Indebtedness tendered pursuant
to an Asset Sale Offer is less than the Excess Proceeds, the Company (or such
Subsidiary) may use such deficiency for any purpose not otherwise prohibited by
the Indenture. If the aggregate principal amount of Notes and such pari passu
Indebtedness surrendered by Holders thereof exceeds the amount of Excess
Proceeds, the Trustee shall select the Notes and such pari passu Indebtedness to
be purchased on a pro rata basis. Holders of Notes that are the subject of an
offer to purchase will receive an Asset Sale Offer from the Company prior to any
related purchase date and may elect to have such Notes purchased by completing
the form entitled "Option of Holder to Elect Purchase" on the reverse of the
Notes.

     9. NOTICE OF REDEMPTION. Notice of redemption will be mailed by first class
mail at least 30 days but not more than 60 days before the redemption date to
each Holder whose Notes are to be redeemed at its registered address. Notes in
denominations larger than $1,000 may be redeemed in part but only in whole
multiples of $1,000, unless all of the Notes held by a Holder are to be
redeemed. On and after the redemption date interest ceases to accrue on Notes or
portions thereof called for redemption.

     10. DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered form
without coupons in denominations of $1,000 and integral multiples of $1,000. The
transfer of Notes may be registered and Notes may be exchanged as provided in
the Indenture. The Registrar and the Trustee may require a Holder, among other
things, to furnish appropriate endorsements and transfer documents and the
Company may require a Holder to pay any taxes and fees required by law or
permitted by the Indenture. The Company need not exchange or register the
transfer of any Note or portion of a Note selected for redemption, except for
the unredeemed portion of any Note being redeemed in part. Also, the Company
need not exchange or register the transfer of any Notes for a period of 15 days
before a selection of Notes to be redeemed or during the period between a record
date and the corresponding Interest Payment Date.

     11. PERSONS DEEMED OWNERS. The registered Holder of a Note may be treated
as its owner for all purposes, other than with respect to the payment of
Additional Amounts.


<PAGE>
                                       -8-


     12. AMENDMENT, SUPPLEMENT AND 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 then outstanding
Notes, and any existing default or compliance with any provision of the
Indenture or the Notes may be waived with the consent of the Holders of a
majority in principal amount of the then outstanding Notes. Without the consent
of any Holder of a Note, the Indenture or the Notes may be amended or
supplemented to cure any ambiguity, defect or inconsistency, to provide for
uncertificated Notes in addition to or in place of certificated Notes, to
provide for the assumption of the Company's obligations to Holders of the Notes
in case of a merger or consolidation or sale of all or substantially all of the
Company's assets, to make any change that would provide any additional rights or
benefits to the Holders of the Notes or that does not adversely affect the legal
rights under the Indenture of any such Holder, to comply with the requirements
of the SEC in order to effect or maintain the qualification of the Indenture
under the TIA.

     13. DEFAULTS AND REMEDIES. Events of Default include: (i) default for 30
days in the payment when due of interest on, or Additional Amounts, if any, with
respect to the Notes, (ii) default in payment when due of principal of or
premium, if any, on the Notes, (iii) failure by the Company or any of its
Restricted Subsidiaries to comply with Section 5.01, 4.07, 4.09 or 4.11 of the
Indenture, (iv) failure by the Company or any of its Restricted Subsidiaries for
15 days after notice to the Company by the Trustee or to the Company and the
Trustee by the Holders of at least 25% in principal amount of the Notes then
outstanding to comply with Section 4.10 or 4.14 of the Indenture or the Notes,
(v) failure by the Company or any of its Restricted Subsidiaries for 60 days
after notice to the Company by the Trustee or to the Company and the Trustee by
the Holders of at least 25% in principal amount of the Notes then outstanding to
comply with any of the other agreements in the Indenture or the Notes, (vi)
voluntary relinquishment by the Company of any of its rights under the
Non-Competition Agreement or failure by the Company for 30 days after written
notice thereof has been given to the Company by the Trustee or to the Company
and the Trustee by Holders of at least 25% of the aggregate principal amount of
the Notes outstanding to enforce any of such rights, in each case which is
materially detrimental to the interests of the Company or the Holders, (vii)
default under certain other agreements relating to Indebtedness of the Company
which default results in the acceleration of such Indebtedness prior to its
express maturity; (viii) certain final judgments for the payment of money that
remain undischarged for a period of 60 days; (ix) certain events of bankruptcy
or insolvency with respect to the Company or any of its Material Subsidiaries.
If any Event of Default occurs and is continuing, the Trustee or the Holders of
at least 25% in principal amount of the then outstanding Notes may declare all
the Notes to be due and payable. Notwithstanding the foregoing, in the case of
an Event of Default arising from certain events of bankruptcy or insolvency, all
outstanding Notes will become due and payable without further action or notice.
Holders may not enforce the Indenture or the Notes except as provided in the
Indenture. Subject to certain limitations, Holders of a majority in principal
amount of the then outstanding Notes may direct the Trustee in its exercise of
any trust or power. The Trustee may withhold from Holders of the Notes notice of
any continuing Default or Event of Default (except a Default or Event of Default
relating to the payment of principal or interest) if it determines that
withholding notice is in their interest. The Holders of a majority in aggregate
principal amount of the Notes then outstanding by notice to the Trustee may on
behalf of the Holders of all of the Notes waive any existing Default or Event of
Default and its consequences under the Indenture except a continuing Default or
Event of Default in the payment of interest on, or the principal of, the Notes.
The Company is required to deliver to the Trustee annually a statement regarding
compliance with the Indenture, and the Company is required upon becoming aware
of any Default or Event of Default, to deliver to the Trustee a statement
specifying such Default or Event of Default.

     14. TRUSTEE DEALINGS WITH COMPANY. The Trustee, 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.


<PAGE>
                                       -9-


     15. NO RECOURSE AGAINST OTHERS. A director, officer, employee, incorporator
or stockholder, of the Company, as such, shall not have any liability for any
obligations of the Company under the Notes or the Indenture or for any claim
based on, in respect of, or by reason of, such obligations or their creation.
Each Holder by accepting a Note waives and releases all such liability. The
waiver and release are part of the consideration for the issuance of the Notes.

     16. GOVERNING LAW. This Note and the Indenture shall be governed by and
construed in accordance with the laws of the State of New York, as applied to
contracts made and performed within the State of New York, without regard to
principles of conflict of laws. Each of the parties hereto and the holders agree
to submit to the jurisdiction of the courts of the State of New York in any
action or proceeding arising out of or relating to this Note.

     17. AUTHENTICATION. This Note shall not be valid until authenticated by the
manual signature of the Trustee or an authenticating agent.

     18. 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).

     19. ADDITIONAL RIGHTS OF HOLDERS OF RESTRICTED GLOBAL NOTES AND RESTRICTED
DEFINITIVE NOTES. In addition to the rights provided to Holders of Notes under
the Indenture, Holders of Restricted Global Notes and Restricted Definitive
Notes shall have all the rights set forth in the A/B Exchange Registration
Rights Agreement dated as of April 26, 2000, among the Company and Donaldson,
Lufkin & Jenrette Securities Corporation, Goldman Sachs & Co., Bear, Stearns &
Co. Inc., Chase Securities Inc., Credit Suisse First Boston Corporation, Morgan
Stanley & Co. Incorporated, Salomon Smith Barney Inc., RBC Dominion Securities
Corporation and TD Securities (USA) Inc. (the "Registration Rights Agreement").

     20. CUSIP NUMBERS. Pursuant to a recommendation promulgated by the
Committee on Uniform Security Identification Procedures, the Company has caused
CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP numbers
in notices of redemption as a convenience to Holders. No representation is made
as to the accuracy of such numbers either as printed on the Notes or as
contained in any notice of redemption and reliance may be placed only on the
other identification numbers placed thereon.

     The Company will furnish to any Holder upon written request and without
charge a copy of the Indenture and/or the Registration Rights Agreement.
Requests may be made to:

                  360networks inc.
                  1510-1066 West Hastings Street
                  Vancouver, BC Canada V6E 3X1
                  Attention:  Secretary
                  Telecopier No.:  (604) 681-6822




<PAGE>
                                      -10-


                                 ASSIGNMENT FORM


     To assign this Note, fill in the form below:

(I) or (we) assign and transfer this Note to:___________________________________
                                               (Insert assignee's legal name)

________________________________________________________________________________
                 (Insert assignee's soc. sec. or tax I.D. no.)


________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________
              (Print or type assignee's name, address and zip code)

and irrevocably appoint_________________________________________________________
to transfer this Note on the books of the Company. The agent may substitute
another to act for him.

Date:

                                  Your Signature:_______________________________
                                                 (Sign exactly as your name
                                                 appears on the face of this
                                                 Note)

Signature Guarantee*:_________________________

* Participant in a recognized Signature Guarantee Medallion Program (or other
signature guarantor acceptable to the Trustee).




<PAGE>
                                      -11-

                       OPTION OF HOLDER TO ELECT PURCHASE


     If you want to elect to have this Note purchased by the Company pursuant to
Section 4.10 or 4.14 of the Indenture, check the appropriate box below:

                           Section 4.10              Section 4.14




     If you want to elect to have only part of the Note purchased by the Company
pursuant to Section 4.10 or Section 4.14 of the Indenture, state the amount you
elect to have purchased:

                                $_______________

Date:

                                 Your Signature:________________________________
                                                (Sign exactly as your name
                                                appears on the face of this
                                                Note)

                                 Tax Identification No.:________________________


Signature Guarantee*:_____________________________

* Participant in a recognized Signature Guarantee Medallion Program (or other
signature guarantor acceptable to the Trustee).




<PAGE>
                                      -12-

             SCHEDULE OF EXCHANGES OF INTERESTS IN THE GLOBAL NOTE*


     The following exchanges of a part of this Global Note for an interest in
another Global Note or for a Definitive Note, or exchanges of a part of another
Global Note or Definitive Note for an interest in this Global Note, have been
made:

<TABLE>
<CAPTION>
                                                                        Principal Amount of          Signature of
                      Amount of decrease in   Amount of increase in       this Global Note       authorized officer of
                       Principal Amount of    Principal Amount of     following such decrease       Trustee or Note
Date of Exchange       this Global Note        this Global Note            (or increase)              Custodian
----------------      ---------------------   ---------------------   -----------------------    ---------------------
<S>                   <C>                     <C>                     <C>                        <C>


</TABLE>



<PAGE>

                                                                       EXHIBIT B


                         FORM OF CERTIFICATE OF TRANSFER


360networks inc.
1510-1066 West Hastings Street
Vancouver, BC Canada V6E 3X1

HSBC Bank USA
140 Broadway, 12th Floor
New York, New York 10005-1180

         Re:      13% Senior Notes due 2008

     Reference is hereby made to the Indenture, dated as of April 26, 2000 (the
"Indenture"), between 360networks inc., as issuer (the "Company"), and HSBC Bank
USA, as trustee. Capitalized terms used but not defined herein shall have the
meanings given to them in the Indenture.

     ___________________, (the "Transferor") owns and proposes to transfer the
Note[s] or interest in such Note[s] specified in Annex A hereto, in the
principal amount of $___________ in such Note[s] or interests (the "Transfer"),
to ___________________________ (the "Transferee"), as further specified in Annex
A hereto. In connection with the Transfer, the Transferor hereby certifies that:

                             [CHECK ALL THAT APPLY]


     1. / / Check if Transferee will take delivery of a beneficial interest in
the 144A Global Note or a Definitive Note Pursuant to Rule 144A. The Transfer is
being effected pursuant to and in accordance with Rule 144A under the United
States Securities Act of 1933, as amended (the "Securities Act"), and,
accordingly, the Transferor hereby further certifies that the beneficial
interest or Definitive Note is being transferred to a Person that the Transferor
reasonably believed and believes is purchasing the beneficial interest or
Definitive Note for its own account, or for one or more accounts with respect to
which such Person exercises sole investment discretion, and such Person and each
such account is a "qualified institutional buyer" within the meaning of Rule
144A in a transaction meeting the requirements of Rule 144A and such Transfer is
in compliance with any applicable blue sky securities laws of any state of the
United States. Upon consummation of the proposed Transfer in accordance with the
terms of the Indenture, the transferred beneficial interest or Definitive Note
will be subject to the restrictions on transfer enumerated in the Private
Placement Legend printed on the 144A Global Note and/or the Definitive Note and
in the Indenture and the Securities Act.

     2. / / Check if Transferee will take delivery of a beneficial interest in
the Regulation S Global Note or a Definitive Note pursuant to Regulation S. The
Transfer is being effected pursuant to and in accordance with Rule 903 or Rule
904 under the Securities Act and, accordingly, the Transferor hereby further
certifies that (i) the Transfer is not being made to a person in the United
States and (x) at the time the buy order was originated, the Transferee was
outside the United States or such Transferor and any Person acting on its behalf
reasonably believed and believes that the Transferee was outside the United
States or (y) the transaction was executed in, on or through the facilities of a
designated offshore securities market and neither such Transferor nor any Person
acting on its behalf knows that the transaction was prearranged with a buyer in
the United States, (ii)


<PAGE>
                                       -2-


no directed selling efforts have been made in contravention of the requirements
of Rule 903(b) or Rule 904(b) of Regulation S under the Securities Act and (iii)
the transaction is not part of a plan or scheme to evade the registration
requirements of the Securities Act. Upon consummation of the proposed transfer
in accordance with the terms of the Indenture, the transferred beneficial
interest or Definitive Note will be subject to the restrictions on Transfer
enumerated in the Private Placement Legend printed on the Regulation S Global
Note and/or the Definitive Note and in the Indenture and the Securities Act.

     3. / / Check and complete if Transferee will take delivery of a beneficial
interest in a Definitive Note pursuant to any provision of the Securities Act
other than Rule 144A or Regulation S. The Transfer is being effected in
compliance with the transfer restrictions applicable to beneficial interests in
Restricted Global Notes and Restricted Definitive Notes and pursuant to and in
accordance with the Securities Act and any applicable blue sky securities laws
of any state of the United States, and accordingly the Transferor hereby further
certifies that (check one):

          (a) / / such Transfer is being effected pursuant to and in accordance
     with Rule 144 under the Securities Act;

                                       or

          (b)/ / such Transfer is being effected to the Company or a subsidiary
     thereof;

                                       or

          (c) / / such Transfer is being effected pursuant to an effective
     registration statement under the Securities Act and in compliance with the
     prospectus delivery requirements of the Securities Act;

                                       or

          (d) / / such Transfer is being effected to an Institutional Accredited
     Investor and pursuant to an exemption from the registration requirements of
     the Securities Act other than Rule 144A, Rule 144 or Rule 904, and the
     Transferor hereby further certifies that it has not engaged in any general
     solicitation within the meaning of Regulation D under the Securities Act
     and the Transfer complies with the transfer restrictions applicable to
     beneficial interests in a Restricted Global Note or Restricted Definitive
     Notes and the requirements of the exemption claimed, which certification is
     supported by (1) a certificate executed by the Transferee in the form of
     Exhibit D to the Indenture and (2) an Opinion of Counsel provided by the
     Transferor or the Transferee (a copy of which the Transferor has attached
     to this certification), to the effect that such Transfer is in compliance
     with the Securities Act. Upon consummation of the proposed transfer in
     accordance with the terms of the Indenture, the transferred beneficial
     interest or Definitive Note will be subject to the restrictions on transfer
     enumerated in the Private Placement Legend printed on the Restricted Global
     Note and/or the Definitive Notes and in the Indenture and the Securities
     Act.

     4. / / Check if Transferee will take delivery of a beneficial interest in
an Unrestricted Global Note or of an Unrestricted Definitive Note.

          (a) / / Check if Transfer is pursuant to Rule 144. (i) The Transfer is
     being effected pursuant to and in accordance with Rule 144 under the
     Securities Act and in compliance with the transfer restrictions contained
     in the Indenture and any applicable blue sky securities laws of any state
     of


<PAGE>
                                       -3-


     the United States and (ii) the restrictions on transfer contained in the
     Indenture and the Private Placement Legend are not required in order to
     maintain compliance with the Securities Act. Upon consummation of the
     proposed Transfer in accordance with the terms of the Indenture, the
     transferred beneficial interest or Definitive Note will no longer be
     subject to the restrictions on transfer enumerated in the Private Placement
     Legend printed on the Restricted Global Notes, on Restricted Definitive
     Notes and in the Indenture.

          (b) / / Check if Transfer is Pursuant to Regulation S. (i) The
     Transfer is being effected pursuant to and in accordance with Rule 903 or
     Rule 904 under the Securities Act and in compliance with the transfer
     restrictions contained in the Indenture and any applicable blue sky
     securities laws of any state of the United States and (ii) the restrictions
     on transfer contained in the Indenture and the Private Placement Legend are
     not required in order to maintain compliance with the Securities Act. Upon
     consummation of the proposed Transfer in accordance with the terms of the
     Indenture, the transferred beneficial interest or Definitive Note will no
     longer be subject to the restrictions on transfer enumerated in the Private
     Placement Legend printed on the Restricted Global Notes, on Restricted
     Definitive Notes and in the Indenture.

          (c) / / Check if Transfer is Pursuant to Other Exemption. (i) The
     Transfer is being effected pursuant to and in compliance with an exemption
     from the registration requirements of the Securities Act other than Rule
     144, Rule 903 or Rule 904 and in compliance with the transfer restrictions
     contained in the Indenture and any applicable blue sky securities laws of
     any State of the United States and (ii) the restrictions on transfer
     contained in the Indenture and the Private Placement Legend are not
     required in order to maintain compliance with the Securities Act. Upon
     consummation of the proposed Transfer in accordance with the terms of the
     Indenture, the transferred beneficial interest or Definitive Note will not
     be subject to the restrictions on transfer enumerated in the Private
     Placement Legend printed on the Restricted Global Notes or Restricted
     Definitive Notes and in the Indenture.

     This certificate and the statements contained herein are made for your
benefit and the benefit of the Company.


                                    _________________________________________
                                           [Insert Name of Transferor]


                                    By:______________________________________
                                        Name:
                                        Title:


Dated:_______________________




<PAGE>
                                      -4-

                       ANNEX A TO CERTIFICATE OF TRANSFER


     1. The Transferor owns and proposes to transfer the following:

                            [CHECK ONE OF (a) OR (b)]

          (a)  / / a beneficial interest in the:

               (i)  / / 144A Global Note (CUSIP US88575TAC09), or

               (ii) / / Regulation S Global Note (CUSIP USC8853QAC45), or

          (b)  / / a Restricted Definitive Note.

     2.   After the Transfer the Transferee will hold:

                                   [CHECK ONE]

          (a)  / / a beneficial interest in the:

               (i)  / / 144A Global Note (CUSIP US88575TAC09), or

               (ii) / / Regulation S Global Note (CUSIP USC8853QAC45), or

               (iii) / / Unrestricted Global Note (CUSIP US88575TAL08); or

          (b)  / / a Restricted Definitive Note; or

          (c)  / / an Unrestricted Definitive Note,

          in accordance with the terms of the Indenture.




<PAGE>


                                                                       EXHIBIT C


                         FORM OF CERTIFICATE OF EXCHANGE


360networks inc.
1510-1066 West Hastings Street
Vancouver, BC Canada V6E 3X1

HSBC Bank USA
140 Broadway, 12th Floor
New York, New York 10005-1180

         Re:      13% Senior Notes due 2008

                              (CUSIP ____________)


     Reference is hereby made to the Indenture, dated as of April 26, 2000 (the
"Indenture"), between 360networks inc., as issuer (the "Company"), and HSBC Bank
USA, as trustee. Capitalized terms used but not defined herein shall have the
meanings given to them in the Indenture.

     __________________________, (the "Owner") owns and proposes to exchange the
Note[s] or interest in such Note[s] specified herein, in the principal amount of
$____________ in such Note[s] or interests (the "Exchange"). In connection with
the Exchange, the Owner hereby certifies that:

     1. Exchange of Restricted Definitive Notes or Beneficial Interests in a
Restricted Global Note for Unrestricted Definitive Notes or Beneficial Interests
in an Unrestricted Global Note

     (a) / / Check if Exchange is from beneficial interest in a Restricted
Global Note to beneficial interest in an Unrestricted Global Note. In connection
with the Exchange of the Owner's beneficial interest in a Restricted Global Note
for a beneficial interest in an Unrestricted Global Note in an equal principal
amount representing the same underlying indebtedness, the Owner hereby certifies
(i) the beneficial interest is being acquired for the Owner's own account
without transfer, (ii) such Exchange has been effected in compliance with the
transfer restrictions applicable to the Global Notes and pursuant to and in
accordance with the United States Securities Act of 1933, as amended (the
"Securities Act"), (iii) the restrictions on transfer contained in the Indenture
and the Private Placement Legend are not required in order to maintain
compliance with the Securities Act and (iv) the beneficial interest in an
Unrestricted Global Note is being acquired in compliance with any applicable
blue sky securities laws of any state of the United States.

     (b) / / Check if Exchange is from beneficial interest in a Restricted
Global Note to Unrestricted Definitive Note. In connection with the Exchange of
the Owner's beneficial interest in a Restricted Global Note for an Unrestricted
Definitive Note, the Owner hereby certifies (i) the Definitive Note is being
acquired for the Owner's own account without transfer, (ii) such Exchange has
been effected in compliance with the transfer restrictions applicable to the
Restricted Global Notes and pursuant to and in accordance with the Securities
Act, (iii) the restrictions on transfer contained in the Indenture and the
Private Placement Legend are not required in order to maintain compliance with
the Securities Act and (iv) the Definitive Note is being acquired in compliance
with any applicable blue sky securities laws of any state of the United States.


<PAGE>
                                       -2-


     (c) / / Check if Exchange is from Restricted Definitive Note to beneficial
interest in an Unrestricted Global Note. In connection with the Owner's Exchange
of a Restricted Definitive Note for a beneficial interest in an Unrestricted
Global Note, the Owner hereby certifies (i) the beneficial interest is being
acquired for the Owner's own account without transfer, (ii) such Exchange has
been effected in compliance with the transfer restrictions applicable to
Restricted Definitive Notes and pursuant to and in accordance with the
Securities Act, (iii) the restrictions on transfer contained in the Indenture
and the Private Placement Legend are not required in order to maintain
compliance with the Securities Act and (iv) the beneficial interest is being
acquired in compliance with any applicable blue sky securities laws of any state
of the United States.

     (d) / / Check if Exchange is from Restricted Definitive Note to
Unrestricted Definitive Note. In connection with the Owner's Exchange of a
Restricted Definitive Note for an Unrestricted Definitive Note, the Owner hereby
certifies (i) the Unrestricted Definitive Note is being acquired for the Owner's
own account without transfer, (ii) such Exchange has been effected in compliance
with the transfer restrictions applicable to Restricted Definitive Notes and
pursuant to and in accordance with the Securities Act, (iii) the restrictions on
transfer contained in the Indenture and the Private Placement Legend are not
required in order to maintain compliance with the Securities Act and (iv) the
Unrestricted Definitive Note is being acquired in compliance with any applicable
blue sky securities laws of any state of the United States.

     2. Exchange of Restricted Definitive Notes or Beneficial Interests in
Restricted Global Notes for Restricted Definitive Notes or Beneficial Interests
in Restricted Global Notes

     (a) / / Check if Exchange is from beneficial interest in a Restricted
Global Note to Restricted Definitive Note. In connection with the Exchange of
the Owner's beneficial interest in a Restricted Global Note for a Restricted
Definitive Note with an equal principal amount, the Owner hereby certifies that
the Restricted Definitive Note is being acquired for the Owner's own account
without transfer. Upon consummation of the proposed Exchange in accordance with
the terms of the Indenture, the Restricted Definitive Note issued will continue
to be subject to the restrictions on transfer enumerated in the Private
Placement Legend printed on the Restricted Definitive Note and in the Indenture
and the Securities Act.

     (b) / / Check if Exchange is from Restricted Definitive Note to beneficial
interest in a Restricted Global Note. In connection with the Exchange of the
Owner's Restricted Definitive Note for a beneficial interest in the [CHECK ONE]
144A Global Note or Regulation S Global Note with an equal principal amount, the
Owner hereby certifies (i) the beneficial interest is being acquired for the
Owner's own account without transfer and (ii) such Exchange has been effected in
compliance with the transfer restrictions applicable to the Restricted Global
Notes and pursuant to and in accordance with the Securities Act, and in
compliance with any applicable blue sky securities laws of any state of the
United States. Upon consummation of the proposed Exchange in accordance with the
terms of the Indenture, the beneficial interest issued will be subject to the
restrictions on transfer enumerated in the Private Placement Legend printed on
the relevant Restricted Global Note and in the Indenture and the Securities Act.



<PAGE>
                                      -3-

     This certificate and the statements contained herein are made for your
benefit and the benefit of the Company.


                                      ______________________________________
                                            [Insert Name of Transferor]


                                      By:___________________________________
                                         Name:
                                        Title:


Dated:_______________________




<PAGE>


                                                                       EXHIBIT D


                            FORM OF CERTIFICATE FROM
                   ACQUIRING INSTITUTIONAL ACCREDITED INVESTOR


360networks inc.
1510-1066 West Hastings Street
Vancouver, BC Canada V6E 3X1

HSBC Bank USA
140 Broadway, 12th Floor
New York, New York 10005-1180

         Re:      13% Senior Notes due 2008

     Reference is hereby made to the Indenture, dated as of April 26, 2000 (the
"Indenture"), between 360networks inc., as issuer (the "Company"), and HSBC Bank
USA, as trustee. Capitalized terms used but not defined herein shall have the
meanings given to them in the Indenture.

     In connection with our proposed purchase of $____________ aggregate
principal amount of:

     (a)  / / a beneficial interest in a Global Note, or

     (b)  / / a Definitive Note,

     we confirm that:

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

     2. We understand that the offer and sale of the Notes have not been
registered under the Securities Act, and that the Notes and any interest therein
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 the Notes or any interest therein,
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 an Opinion of Counsel in form
reasonably acceptable to the Company to the effect 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(k) under the Securities Act or (F) pursuant to an
effective registration statement under the Securities Act, and we further agree
to provide to any person purchasing the Definitive Note or beneficial interest
in a Global Note from us in a transaction meeting the requirements of clauses
(A) through (E) of this paragraph a notice advising such purchaser that resales
thereof are restricted as stated herein.


<PAGE>
                                       -2-


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

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

     5. We are acquiring the Notes or beneficial interest therein 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.


                                ________________________________________________
                                      [Insert Name of Accredited Investor]


                                By:_____________________________________________
                                   Name:
                                   Title:


Dated:_______________________