Document:

<PAGE>   1
                                                                   EXHIBIT 10.12

===============================================================================

                     AMENDED AND RESTATED CREDIT AGREEMENT

                          dated as of February 8, 2000

                                  by and among

                               ALAMOSA PCS, INC.
                                  as Borrower

                                      and

                           ALAMOSA PCS HOLDINGS, INC.
                          TEXAS TELECOMMUNICATIONS, LP
                                      and
                     ALAMOSA WISCONSIN LIMITED PARTNERSHIP
                                 as Guarantors

                                      and

                              NORTEL NETWORKS INC.
                            as Administrative Agent

                                      and

                            THE LENDERS NAMED HEREIN

                  $250,000,000 ADVANCING TERM LOAN FACILITIES

===============================================================================

<PAGE>   2

                               TABLE OF CONTENTS
<TABLE>
<CAPTION>
                                                                                                               Page
                                                                                                               ----
<S>                                                                                                            <C>
ARTICLE 1         Definitions.....................................................................................3
         Section 1.1       Definitions, etc.......................................................................3
         Section 1.2       Other Definitional Provisions.........................................................32
         Section 1.3       Accounting Terms and Determinations...................................................32
         Section 1.4       Financial Covenants and Reporting.....................................................33

ARTICLE 2         Loans..........................................................................................33
         Section 2.1       Commitments...........................................................................33
         Section 2.2       Notes.................................................................................35
         Section 2.3       Repayment of Loans....................................................................35
         Section 2.4       Interest..............................................................................36
         Section 2.5       Borrowing Procedure...................................................................37
         Section 2.6       Optional Prepayments, Conversions and Continuations of Loans..........................38
         Section 2.7       Mandatory Prepayments.................................................................38
         Section 2.8       Minimum Amounts.......................................................................39
         Section 2.9       Certain Notices.......................................................................39
         Section 2.10      Use of Proceeds.......................................................................40
         Section 2.11      Fees..................................................................................42
         Section 2.12      Computations..........................................................................42
         Section 2.13      Termination or Reduction of Commitments...............................................42

ARTICLE 3         Payments.......................................................................................43
         Section 3.1       Method of Payment.....................................................................43
         Section 3.2       Pro Rata Treatment....................................................................44
         Section 3.3       Sharing of Payments, Etc..............................................................44
         Section 3.4       Non-Receipt of Funds by the Administrative Agent......................................44
         Section 3.5       Taxes.................................................................................45
         Section 3.6       Withholding Tax Exemption.............................................................46
         Section 3.7       Reinstatement of Obligations..........................................................46
         Section 3.8       No Force Majeure, Disputes............................................................47

ARTICLE 4         Yield Protection and Illegality................................................................47
         Section 4.1       Additional Costs......................................................................47
         Section 4.2       Limitation on Types of Loans..........................................................49
         Section 4.3       Illegality............................................................................49
         Section 4.4       Treatment of Affected Loans...........................................................49
         Section 4.5       Compensation..........................................................................50
         Section 4.6       Capital Adequacy......................................................................50
         Section 4.7       Additional Interest on Eurodollar Loans...............................................51
         Section 4.8       Replacement of Lenders................................................................51
</TABLE>

CREDIT AGREEMENT - Page i

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<TABLE>
<S>                                                                                                              <C>
ARTICLE 5         Security.......................................................................................51
         Section 5.1       Collateral............................................................................51
         Section 5.2       Guaranties............................................................................53
         Section 5.3       New Subsidiaries; Additional Capital Stock............................................53
         Section 5.4       Mortgaged Properties; Landlord Subordinations or Waivers..............................54
         Section 5.5       Setoff................................................................................55
         Section 5.6       Further Assurances....................................................................55

ARTICLE 6         Conditions Precedent...........................................................................55
         Section 6.1       Initial Extension of Credit...........................................................55
         Section 6.2       All Extensions of Credit..............................................................60
         Section 6.3       Closing Certificates..................................................................61

ARTICLE 7         Representations and Warranties.................................................................61
         Section 7.1       Existence, etc........................................................................61
         Section 7.2       Financial Statements..................................................................62
         Section 7.3       Corporate Action; No Breach...........................................................62
         Section 7.4       Operation of Business; Licenses.......................................................63
         Section 7.5       Intellectual Property.................................................................63
         Section 7.6       Litigation and Judgments..............................................................63
         Section 7.7       Rights in Properties; Liens...........................................................64
         Section 7.8       Enforceability........................................................................64
         Section 7.9       Approvals.............................................................................64
         Section 7.10      Debt..................................................................................64
         Section 7.11      Taxes.................................................................................65
         Section 7.12      Margin Securities.....................................................................65
         Section 7.13      ERISA.................................................................................65
         Section 7.14      Disclosure............................................................................66
         Section 7.15      Loan Parties; Capitalization..........................................................66
         Section 7.16      Compliance with Laws..................................................................66
         Section 7.17      Investment Company Act................................................................66
         Section 7.18      Public Utility Holding Company Act....................................................66
         Section 7.19      Environmental Matters.................................................................67
         Section 7.20      Year 2000 Compliance..................................................................68
         Section 7.21      Labor Disputes and Acts of God........................................................68
         Section 7.22      Material Contracts....................................................................68
         Section 7.23      Bank Accounts.........................................................................69
         Section 7.24      Outstanding Securities................................................................69
         Section 7.25      Solvency..............................................................................69
         Section 7.26      Employee Matters......................................................................69
         Section 7.27      Insurance.............................................................................69
         Section 7.28      Common Enterprise.....................................................................69
         Section 7.29      Reorganization Transactions.  ........................................................69
</TABLE>

CREDIT AGREEMENT - Page ii

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<TABLE>
<S>                                                                                                              <C>
ARTICLE 8         Affirmative Covenants..........................................................................70
         Section 8.1       Reporting Requirements................................................................70
         Section 8.2       Maintenance of Existence; Conduct of Business.........................................74
         Section 8.3       Maintenance of Properties and Permits.................................................74
         Section 8.4       Taxes and Claims......................................................................74
         Section 8.5       Insurance.............................................................................74
         Section 8.6       Inspection Rights.....................................................................76
         Section 8.7       Keeping Books and Records.............................................................76
         Section 8.8       Compliance with Laws..................................................................76
         Section 8.9       Compliance with Agreements............................................................77
         Section 8.10      Further Assurances....................................................................77
         Section 8.11      ERISA.................................................................................77
         Section 8.12      Interest Rate Protection..............................................................77
         Section 8.13      Sprint Agreements. ...................................................................77
         Section 8.14      Non-Consolidation.....................................................................77
         Section 8.15      Year 2000 Compliance..................................................................78
         Section 8.16      Trade Accounts Payable................................................................78
         Section 8.17      Delivery of Certain Amendments and Material Contracts.................................78
         Section 8.18      Ownership of Operating Assets.........................................................78
         Section 8.19      Observation Rights....................................................................78

ARTICLE 9         Negative Covenants.............................................................................79
         Section 9.1       Debt.  ...............................................................................79
         Section 9.2       Limitation on Liens...................................................................80
         Section 9.3       Mergers, Etc..........................................................................80
         Section 9.4       Restricted Payments...................................................................81
         Section 9.5       Investments...........................................................................82
         Section 9.6       Limitation on Issuance of Capital Stock...............................................83
         Section 9.7       Transactions with Affiliates..........................................................83
         Section 9.8       Disposition of Property...............................................................83
         Section 9.9       Sale and Leaseback....................................................................84
         Section 9.10      Lines of Business.....................................................................85
         Section 9.11      Environmental Protection..............................................................85
         Section 9.12      Intercompany Transactions.............................................................85
         Section 9.13      Management Fees.......................................................................85
         Section 9.14      Supply Agreement......................................................................86
         Section 9.15      Modification of Certain Agreements....................................................86
         Section 9.16      ERISA.................................................................................86
         Section 9.17      Sprint PCS Fees.......................................................................86
         Section 9.18      No Prepayment of Debt, Etc............................................................86

ARTICLE 10        Financial Covenants............................................................................87
         Section 10.1      Total Debt to Total Capitalization....................................................87
         Section 10.2      Total Debt  to Annualized EBITDA......................................................88
         Section 10.3      Annualized EBITDA.....................................................................88

</TABLE>

CREDIT AGREEMENT - Page iii

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<TABLE>
<S>                                                                                                              <C>
         Section 10.4      Fixed Charge Coverage.................................................................88
         Section 10.5      Capital Expenditures..................................................................88
         Section 10.6      Quarterly Minimum Revenue Levels......................................................88
         Section 10.7      Wireless Subscribers..................................................................88
         Section 10.8      Operating Leases......................................................................88

ARTICLE 11        Default........................................................................................89
         Section 11.1      Events of Default.....................................................................89
         Section 11.2      Remedies..............................................................................92
         Section 11.3      Performance by the Administrative Agent, etc..........................................93

ARTICLE 12        The Administrative Agent.......................................................................93
         Section 12.1      Appointment, Powers and Immunities....................................................93
         Section 12.2      Rights of Administrative Agent as a Lender............................................94
         Section 12.3      Defaults..............................................................................94
         Section 12.4      INDEMNIFICATION.......................................................................95
         Section 12.5      Independent Credit Decisions..........................................................96
         Section 12.6      Several Commitments...................................................................96
         Section 12.7      Successor Administrative Agent........................................................96

ARTICLE 13        Miscellaneous..................................................................................97
         Section 13.1      Expenses..............................................................................97
         Section 13.2      INDEMNIFICATION.......................................................................97
         Section 13.3      Limitation of Liability...............................................................98
         Section 13.4      No Duty...............................................................................99
         Section 13.5      No Fiduciary Relationship.............................................................99
         Section 13.6      Equitable Relief......................................................................99
         Section 13.7      No Waiver; Cumulative Remedies........................................................99
         Section 13.8      Successors and Assigns................................................................99
         Section 13.9      Survival.............................................................................103
         Section 13.10     ENTIRE AGREEMENT.....................................................................103
         Section 13.11     Amendments...........................................................................103
         Section 13.12     Maximum Interest Rate................................................................104
         Section 13.13     Notices..............................................................................105
         Section 13.14     GOVERNING LAW; SUBMISSION TO JURISDICTION;
                           SERVICE OF PROCESS...................................................................105
         Section 13.15     Counterparts.........................................................................106
         Section 13.16     Severability.........................................................................106
         Section 13.17     Headings.............................................................................106
         Section 13.18     Construction.........................................................................106
         Section 13.19     Independence of Covenants............................................................106
         Section 13.20     Confidentiality......................................................................106
         Section 13.21     WAIVER OF JURY TRIAL.................................................................107
         Section 13.22     Approvals and Consent................................................................107
         Section 13.23     Service of Process...................................................................108

</TABLE>

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<TABLE>
<S>                                                                                                              <C>
         Section 13.24     Reaffirmation of Supply Agreement....................................................108
         Section 13.25     Amendment and Restatement of the Original Credit Agreement...........................108
         Section 13.26     Assignments of Original Loans........................................................108
         Section 13.27     No Requirement of Assumption or Payment of Another Person's
                           Debt.................................................................................108

</TABLE>

CREDIT AGREEMENT - Page v

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<TABLE>

                               INDEX TO EXHIBITS

<S>                   <C>    <C>
Exhibit A             -      Form of Assignment and Acceptance
Exhibit B-1           -      Form of Tranche A Note
Exhibit B-2           -      Form of Tranche B Note
Exhibit B-3           -      Form of Tranche C Note
Exhibit C             -      Form of Notice of Borrowings, Conversions, Continuations and
                             Prepayments
Exhibit D             -      Form of Compliance Certificate
Exhibit E             -      Form of Permitted Third-Party Expenses Borrowing Base Report

                               INDEX TO SCHEDULES

Schedule 1.1(a)       -      Permitted Holders
Schedule 1.1(b)       -      Certain Permitted Liens
Schedule 1.1(c)       -      Service Area (Basic Trading Areas)
Schedule 7.4          -      Permits, Franchises and Authorizations required by Governmental
                             Requirements or issued by Governmental Authorities
Schedule 7.5          -      Intellectual Property
Schedule 7.6          -      Litigation, Etc.
Schedule 7.7          -      Real Property
Schedule 7.10         -      Existing Debt
Schedule 7.13         -      Plans
Schedule 7.15         -      Subsidiaries; Capitalization
Schedule 7.22         -      Material Contracts
Schedule 7.23         -      Bank Accounts
Schedule 7.26         -      Employee Matters
Schedule 7.27         -      Insurance
Schedule 8.15         -      Year 2000 Compliance
Schedule 9.5          -      Certain Investments
Schedule 10.1         -      Total Debt to Total Capitalization
Schedule 10.2         -      Total Debt to Annualized EBITDA
Schedule 10.3         -      Annualized EBITDA
Schedule 10.4         -      Fixed Charge Coverage
Schedule 10.5         -      Capital Expenditures
Schedule 10.6         -      Quarterly Minimum Revenue Levels
Schedule 10.7         -      Wireless Subscribers
</TABLE>

CREDIT AGREEMENT - Page vi

<PAGE>   8

                                CREDIT AGREEMENT

         THIS AMENDED AND RESTATED CREDIT AGREEMENT, dated as of February 8,
2000, is by and among ALAMOSA PCS, INC. (the "Borrower"), a Delaware
corporation, ALAMOSA PCS HOLDINGS, INC. ("Holdings"), a Delaware corporation,
TEXAS TELECOMMUNICATIONS, LP ("Alamosa Texas"), a Texas limited partnership,
ALAMOSA WISCONSIN LIMITED PARTNERSHIP ("Alamosa Wisconsin"), a Wisconsin
limited partnership, each of the lending entities which is a party hereto (as
evidenced by the signature pages of this Agreement) or which may from time to
time become a party hereto as a lender or any successor or assignee thereof
(individually, a "Lender" and, collectively, the "Lenders"), and NORTEL
NETWORKS INC., a Delaware corporation, as administrative agent for itself and
the other Lenders (in such capacity, together with its successors in such
capacity, the "Administrative Agent").

                                   RECITALS:

         A. Alamosa PCS LCC (the "Original Borrower"), a Texas limited
liability company, is a party to that certain Credit Agreement dated as of June
10, 1999, among the Original Borrower, the lenders named therein (including
Nortel Networks Inc., the "Original Lenders") and Nortel Networks Inc. as
administrative agent (the "Original Administrative Agent") for itself and such
lenders (as amended by that certain First Amendment to Credit Agreement dated
as of December 22, 1999, the "Original Credit Agreement") pursuant to which the
Original Borrower was provided advancing term loan facilities in the aggregate
principal amount of $123,000,000. The Original Lenders made loans to the
Original Borrower under the Original Credit Agreement, which loans remain
outstanding.

         B. Prior hereto and (in certain cases, substantially concurrently
herewith), the following transactions have occurred (collectively the
"Reorganization Transactions"):

         (i) Holdings was incorporated and organized (but no Capital Stock of
Holdings was initially issued);

         (ii) the Original Borrower formed and organized (a) Alamosa Wisconsin
GP, LLC ("Alamosa Wisconsin GP"), a Wisconsin limited liability company and the
general partner of Alamosa Wisconsin, (b) Alamosa Wisconsin, (c) Alamosa
Delaware GP, LLC ("Alamosa Texas GP"), a Delaware limited liability company and
the general partner of Alamosa Texas, and (d) Alamosa Texas;

         (iii) the Original Borrower formed and organized the Borrower as a
wholly-owned subsidiary of the Original Borrower;

         (iv) Holdings issued 100 shares of its common stock to the Original
Borrower, with the effect that Holdings became a wholly-owned subsidiary of the
Original Borrower;

CREDIT AGREEMENT - Page 1

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         (v) the Original Borrower contributed 1% of its assets (other than its
Wisconsin assets) to Alamosa Texas GP and 99% of its assets (other than its
Wisconsin assets) to Alamosa Texas, and Alamosa Texas GP contributed all of its
assets to Alamosa Texas;

         (vi) the Original Borrower contributed 1% of its Wisconsin assets to
Alamosa Wisconsin GP and 99% of its Wisconsin assets to Alamosa Wisconsin, and
Alamosa Wisconsin GP contributed all of its assets to Alamosa Wisconsin;

         (vii) the Original Borrower converted from a Texas limited liability
company to a Texas corporation using the name "Alamosa PCS Holdings, Inc."
("Texas Holdings");

         (viii) Texas Holdings contributed to the Borrower (a) 100% of the
limited liability company interests in Alamosa Texas GP, (b) 100% of the
limited liability company interests in Alamosa Wisconsin GP, (c) 99% of the
limited partnership interests in Alamosa Texas, and (d) 98.75% of the limited
partnership interests in Alamosa Wisconsin and, in connection with the
foregoing contributions of assets, the Borrower assumed all of the Original
Obligations;

         (ix) Texas Holdings merged with and into Holdings, with Holdings being
the surviving entity in such merger; and

         (x) in connection with each of the aforesaid contributions and/or
transfers of assets, such assets were contributed and/or transferred subject to
the security interests in such assets previously granted by the Original
Borrower to the Original Administrative Agent in connection with the Original
Credit Agreement.

         C. The Borrower, Alamosa Texas and Alamosa Wisconsin are parties to
various agreements with Sprint PCS relating to the construction and operation
of PCS systems in the Service Area.

         D. The Borrower desires to amend and restate the advancing term loan
facilities under the original Credit Agreement and to obtain advancing term
loan facilities in the aggregate principal amount of $250,000,000 to finance a
portion of its costs to construct and operate such PCS systems.

         E. The Lender(s) identified on the signature pages of this Agreement
desire to provide such credit facilities with the assistance of the
Administrative Agent upon and subject to the terms and provisions contained in
this Agreement.

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants herein contained, the parties hereto hereby agree as follows:

CREDIT AGREEMENT - Page 2

<PAGE>   10
                                   ARTICLE 1

                                  Definitions

     Section 1.1    Definitions, etc. As used in this Agreement, the following
 terms shall have the following meanings:

     "Additional Costs" means as specified in Section 4.1(a).

     "Adjusted Eurodollar Rate" means, for any Eurodollar Loan for any Interest
Period therefor, the rate per annum (rounded upwards, if necessary, to the
nearest 1/16 of one percent) determined by the Administrative Agent to be equal
to (a) the Eurodollar Rate for such Eurodollar Loan for such Interest Period
divided by (b) one minus the Reserve Requirement for such Eurodollar Loan for
such Interest Period.

     "Adjusted Net Income" means for any period, Consolidated Net Income less
(without duplication) to the extent that any of the following shall have been
included in Consolidated Net Income for such period (a) any net gain or loss
arising from the sale of capital assets, (b) any net gain or loss arising from
any write-up or write-down of assets, (c) earnings or losses of any other
Person, substantially all of the assets of which have been acquired by the
Borrower or a Consolidated Subsidiary of the Borrower in any manner, to the
extent that such earnings or losses were realized by such other Person prior to
the date of such acquisition, (d) earnings or losses of any Person (other than a
Consolidated Subsidiary of the Borrower) in which the Borrower or a
Consolidated Subsidiary has an ownership interest, unless such earnings have
actually been received by the Borrower or such Consolidated Subsidiary in the
form of cash distributions, and (e) any net gain or loss arising from the
acquisition of any securities of the Borrower or a Consolidated Subsidiary of
the Borrower.

     "Administrative Agent" means as specified in the introductory paragraph of
this Agreement.

     "Administrative Agent's Letter" means the letter agreement dated as of
February 8, 2000 between the Administrative Agent and the Borrower.

     "Advances" means the Loans made under this Agreement.

     "Affiliate" means, as to any Person, any other Person (a) that directly or
indirectly through one or more intermediaries controls or is controlled by, or
is under direct or indirect common control with, such first Person, (b) that
directly or indirectly beneficially owns or holds ten percent or more of any
class of voting Capital Stock of such first Person, or (c) ten percent or more
of the voting Capital Stock of which is directly or indirectly beneficially
owned or held by such first Person. For the purposes of this definition,
"control" when used with respect to any Person means the power to direct the
management and policies of such Person, directly or indirectly, whether through
the ownership of voting securities, by contract or otherwise; and the terms
"controlling" and "controlled" have meanings correlative to the foregoing. For
purposes of the Loan Documents, neither the Administrative Agent nor any Lender
shall be deemed to be an Affiliate of the Borrower or any of its Subsidiaries.

CREDIT AGREEMENT - Page 3
<PAGE>   11

         "Aggregate Commitments" means, as to all Lenders, the Tranche A
Commitments, Tranche B Commitments and Tranche C Commitments.

         "Agreement" means this Agreement and any and all amendments,
modifications, supplements, renewals, extensions or restatements hereof.

         "Alamosa Texas" means as specified in the initial paragraph of this
Agreement.

         "Alamosa Texas GP" means as specified in clause (iii) of Recital B.

         "Alamosa Wisconsin" means as specified in the initial paragraph of
this Agreement.

         "Alamosa Wisconsin GP" means as specified in clause (ii) of Recital B.

         "Amortization Commencement Date" means the earlier to occur of (a)
August 8, 2002, or (b) February 8, 2001, if less than $100,000,000 in aggregate
principal amount of the Loans has been advanced as of such date.

         "Annualized EBITDA" means, for the applicable period, EBITDA for the
two most recently completed fiscal quarters multiplied by two.

         "Applicable Lending Office" means for each Lender and each Type of
Loan, the lending office of such Lender (or an Affiliate of such Lender)
designated for such Type of Loan below its name on the signature pages hereof
(or, with respect to a Lender that becomes a party to this Agreement pursuant
to an assignment made in accordance with Section 13.8, in the Assignment and
Acceptance executed by it) or such other office of such Lender (or an Affiliate
of such Lender) as such Lender may from time to time specify to the Borrower
and the Administrative Agent as the office by which its Loans of such Type are
to be made and maintained.

         "Applicable Margin" means the rate per annum equal to (a) with respect
to each Base Rate Loan, two and three-quarters of one percent (2.75%) and (b)
with respect to each Eurodollar Loan, three and three-quarters of one percent
(3.75%).

         "Approved Fund" means (a) with respect to any Lender which is a fund
primarily engaged in making, purchasing or otherwise investing in commercial
loans, any other fund which is primarily engaged in making, purchasing or
otherwise investing in commercial loans or extending, or investing in
extensions of, credit for its own account in the ordinary course of its
business and which is managed or advised by the same investment advisor as such
Lender or by an Affiliate of such investment advisor or (b) any other entity
which has been approved by the Administrative Agent and which is (or which is
managed by a manager which manages funds which are) primarily engaged in
making, purchasing or otherwise investing in commercial loans or extending, or
investing in extensions of, credit for its own account in the ordinary course
of its business; provided, however, that Approved Fund shall not include any
Affiliate of the Borrower.

CREDIT AGREEMENT - Page 4

<PAGE>   12

         "Approved Subordinated Debt" means all Debt which is unsecured and
which is structurally or contractually subordinated, as to payment, to the
payment of the Loans and other Obligations on terms, and pursuant to agreements
in form and substance, satisfactory to, and approved in writing by, the
Administrative Agent and the Required Lenders.

         "Approved Subordinated Debt Documents" means any and all agreements,
documents and instruments now or hereafter evidencing or governing any Approved
Subordinated Debt.

         "Asset Disposition" means the disposition of any or all of the
Property of any Loan Party, other than a disposition of Capital Stock of an
Unrestricted Subsidiary, whether by sale, lease, transfer, assignment,
condemnation or otherwise, but excluding (a) sales of inventory in the ordinary
course of business, (b) the grant of a Lien as security, (c) any involuntary
disposition resulting from casualty damage to Property, and (d) dispositions of
equipment if and to the extent that the equipment disposed of is, concurrently
therewith, exchanged or replaced by equipment of equal or greater value.

         "Assignee" means as specified in Section 13.8(b).

         "Assigning Lender" means as specified in Section 13.8(b).

         "Assignment and Acceptance" means an assignment and acceptance entered
into by a Lender and its Assignee and accepted by the Administrative Agent
pursuant to Section 13.8(e), in substantially the form of Exhibit A hereto.

         "Availability" means, as of any date of determination, the lesser of
(a) the unused amount of the Commitments or (b) the sum of (i) 150% of the
amount paid by the Borrower and its Subsidiaries to Nortel Networks for Nortel
Networks Goods and Services for the Service Area Network plus (ii) the unused
amount of the Tranche C Commitments.

         "Bankruptcy Code" means as specified in Section 11.1(e).

         "Base Rate" means, at any time, the greater of (a) the rate of
interest per annum then most recently announced or established by the Reference
Bank at its principal office in New York City as its highest commercial prime
or base rate then in effect, or (b) the Federal Funds Rate then in effect plus
one-half of one percent (0.50%). The Base Rate may not necessarily be the
lowest rate of interest charged by the Reference Bank to its commercial
borrowers. Each change in any interest rate provided for herein based upon the
prime or base rate or the Federal Funds Rate resulting from a change in the
prime or base rate or the Federal Funds Rate, respectively, shall take effect
without notice to the Borrower at the time of such change in the prime or base
rate or the Federal Funds Rate, respectively.

         "Base Rate Loans" means Loans that bear interest at rates based upon
the Base Rate.

         "Basle Accord" means the proposals for risk-based capital framework
described by the Basle Committee on Banking Regulations and Supervisory
Practices in its paper entitled "International

CREDIT AGREEMENT - Page 5

<PAGE>   13

Convergence of Capital Measurement and Capital Standards" dated July 1988, as
amended, supplemented and otherwise modified and in effect from time to time,
or any replacement thereof.

         "Board of Directors" means (a) with respect to Holdings, the Borrower
and any Subsidiary of the Borrower which is a corporation, the board of
directors of Holdings, the Borrower or such Subsidiary of the Borrower, as
applicable based upon the context in which such term appears, (b) with respect
to Alamosa Texas and Alamosa Wisconsin, the general partner of Alamosa Texas
and Alamosa Wisconsin, respectively, (c) with respect to Alamosa Texas GP and
Alamosa Wisconsin GP, the manager of Alamosa Texas GP and Alamosa Wisconsin GP,
respectively, and (d) with respect to any other Loan Party, the board of
directors if such Loan Party is a corporation, the general partner if such Loan
Party is a limited partnership, the managing partner if such Loan Party is a
general partnership, or the manager if such Loan Party is a limited liability
company or an analogous body, officer or representative which is the functional
equivalent of the board of directors of a corporation if such Loan Party is
another type of entity, in each case which body, officer or representative has
the power and authority to authorize and effectuate the execution, delivery and
performance of the Loan Documents and other actions to be taken by such Loan
Party.

         "Board Resolution" means a resolution certified by the Secretary or an
Assistant Secretary or analogous officer of any Loan Party, as applicable based
upon the context in which such term appears, to have been duly adopted by the
Board of Directors of such entity and to be in full force and effect on the
date of such certification.

         "Borrower" means as specified in the initial paragraph of this
Agreement.

         "BTA" means a Basic Trading Area for which a Basic Trading Area (BTA)
license is issued by the FCC.

         "Build-out Plan" means the plan agreed upon by the Borrower and the
Operating Subsidiaries and Sprint PCS, along with any modifications and updates
to the plan, respecting the construction and design of the Service Area
Network, a copy of which is attached as Exhibit 2.1 to the Sprint Management
Agreements.

         "Business Day" means (a) any day other than a Saturday, Sunday or
other day on which commercial banks are authorized or required by law to close
in New York, New York or Dallas, Texas, and (b) with respect to all borrowings,
payments, Conversions, Continuations, Interest Periods and notices in
connection with Eurodollar Loans, any day which is a Business Day described in
clause (a) above and which is also a day on which dealings in Dollar deposits
are carried out in the London interbank market.

         "Business Plan" means the Borrower's marketing and construction plans
for the Service Area Network, budget and schedule as submitted to and approved
by the Administrative Agent, including financial projections of the Borrower
and its respective Consolidated Subsidiaries for the eight year period
beginning on January 1, 2000, certified by the chief financial officer of the
Borrower as being prepared generally in accordance with GAAP (except for the
absence of footnotes), such construction plans giving effect to the Build-out
Plan and such projections giving effect to the Debt to be incurred

CREDIT AGREEMENT - Page 6

<PAGE>   14

under this Agreement as well as the other Debt to be incurred by the Borrower
and its Consolidated Subsidiaries during such period. Unless any amendment or
modification thereto or replacement thereof is subsequently approved by the
Administrative Agent in accordance with Section 9.15, the Business Plan
identified as "Version 31D-1" shall be the Business Plan for purposes of this
Agreement.

         "Capital Expenditures" means amounts paid or Debt incurred by the
Borrower and/or any of its Subsidiaries in connection with the purchase or
lease by any such Person or Persons of Property that would be required to be
capitalized and shown on the balance sheet of such Person or Persons in
accordance with GAAP.

         "Capital Lease Obligations" means, as to any Person, the obligations
of such Person to pay rent or other amounts under a lease of (or other
agreement conveying the right to use) real and/or personal Property, which
obligations are classified as a capital lease on a balance sheet of such Person
under GAAP. For purposes of this Agreement, the amount of such Capital Lease
Obligations shall be the capitalized amount thereof, determined in accordance
with GAAP.

         "Capital Stock" means corporate stock and any and all securities,
shares, partnership interests, limited partnership interests, limited liability
company interests, membership interests, equity interests, participations,
rights or other equivalents (however designated) of corporate stock or any of
the foregoing issued by any entity (whether a corporation, a partnership or
another entity) and includes, without limitation, securities convertible into
Capital Stock and rights, warrants or options to acquire Capital Stock.

         "Change in Control" means the existence or occurrence of any of the
following: (a) any of the Capital Stock of the Borrower is owned by any Person
other than Holdings; (b) any Capital Stock of any Subsidiary of the Borrower is
owned directly or indirectly by any Person other than the Borrower, provided,
that with respect to (i) Alamosa Texas, up to one percent of its ownership
interests may be owned by Alamosa Texas GP and (ii) with respect to Alamosa
Wisconsin, up to one percent of its ownership interests may be owned by Alamosa
Wisconsin GP and up to three percent of its limited partnership interests may
be owned by Wisconsin telephone companies, in each case (i.e., as to each of
clauses (i) and (ii) preceding) without a Change in Control resulting from such
ownership by other than the Borrower, (c) any Person or two or more Persons
(other than the Permitted Holders) acting as a group (as defined in Section
13d-3 of the Exchange Act) shall have acquired beneficial ownership (within the
meaning of Rule 13d-3 of the Securities and Exchange Commission under the
Exchange Act) of 35% or more of the outstanding shares of Voting Stock of
Holdings; (d) individuals who, as of the Closing Date, constitute the Board of
Directors of Holdings (the "Holdings Incumbent Board") cease for any reason to
constitute at least a majority of the Board of Directors of Holdings; provided,
however, that any individual becoming a director of Holdings subsequent to the
Closing Date whose election, or nomination for election by Holdings'
shareholders was approved by a vote of at least a majority of the directors
then comprising the Holdings Incumbent Board shall be considered as though such
individual were a member of the Holdings Incumbent Board, but excluding, for
this purpose, any such individual whose initial assumption of office occurs as
a result of either an actual or threatened election contest (as such terms are
used in Rule 14a-11 of Regulation 14A promulgated under the Exchange Act) or
other actual or threatened

CREDIT AGREEMENT - Page 7

<PAGE>   15

solicitation of proxies or contest by or on behalf of a Person other than the
Board of Directors of Holdings; or (e) the consummation of any transaction the
result of which is that any Person or group beneficially owns ten percent (10%)
or more of the outstanding shares of Voting Stock of Holdings and more of the
Voting Stock of Holdings than is beneficially owned, in the aggregate, by the
Permitted Holders.

         "Closing Date" means the date of the making of the initial Loan under
this Agreement.

         "Code" means the Internal Revenue Code of 1986, as amended, and the
regulations promulgated and rulings issued thereunder.

         "Collateral" means all Property of any Person of any nature whatsoever
upon which a Lien is created or purported to be created by any Loan Document as
security for the Obligations or any portion thereof.

         "Commitment Percentage" means, as to any Lender and as to the Tranche
A Commitments, the Tranche B Commitments, the Tranche C Commitments or the
Aggregate Commitments (as applicable based upon the context in which such term
is used), the percentage equivalent of a fraction, the numerator of which is
the amount of the outstanding Tranche A Commitments, Tranche B Commitments,
Tranche C Commitments or the Aggregate Commitments (as applicable) of such
Lender (or, if such applicable commitment has terminated or expired, the
outstanding principal amount of Tranche A Loans, Tranche B Loans, Tranche C
Loans or Loans, respectively, of such Lender) and the denominator of which is
the aggregate amount of the outstanding Tranche A Commitments, Tranche B
Commitments, Tranche C Commitments or Aggregate Commitments (as applicable) of
all Lenders (or, if such applicable commitments have terminated or expired, the
aggregate outstanding principal amount of Tranche A Loans, Tranche B Loans,
Tranche C Loans or Loans, respectively, of all Lenders), as adjusted from time
to time in accordance with Section 13.8.

         "Commitments" means, as to any Lender, such Lender's Tranche A
Commitment, Tranche B Commitment and Tranche C Commitment.

         "Communications Act" means the Communications Act of 1934, and any
similar or successor federal statute, and the rules and regulations of the FCC
thereunder, all as amended and as the same may be in effect from time to time.

         "Consent and Agreement (Alamosa Texas)" means that certain Amended and
Restated Consent and Agreement dated as of February 8, 2000, among Sprint
Spectrum, SprintCom, Inc., Sprint Communications Company, L.P., Cox
Communications PCS, L.P., Cox PCS License, LLC, WirelessCo, L.P. and the
Administrative Agent, as acknowledged, consented and agreed to by the Borrower
and the Operating Subsidiaries and certain other Loan Parties, and any and all
amendments, modifications, supplements, renewals, extensions or restatements
thereof.

         "Consent and Agreement (Alamosa Wisconsin)" means that certain Consent
and Agreement dated as of February 8, 2000, among Sprint Spectrum, WirelessCo,
L.P., Sprint Communications Company, L.P. and the Administrative Agent, as
acknowledged, consented and agreed to by the

CREDIT AGREEMENT - Page 8

<PAGE>   16

Borrower and the Operating Subsidiaries and certain other Loan Parties, and any
and all amendments, modifications, supplements, renewals, extensions or
restatements thereof.

         "Consents and Agreements" means the Consent and Agreement (Alamosa
Texas) and the Consent and Agreement (Alamosa Wisconsin).

         "Consolidated Fixed Charges" means, for any period, the sum of (a)
Consolidated Interest Expense for the Borrower and its Consolidated
Subsidiaries paid or payable in cash during such period (excluding interest
accrued on the Loans on or before the second anniversary of the Closing Date
which has been paid by the Borrower with the proceeds of Tranche C Loans), plus
(b) all scheduled payments (as such scheduled payments are reduced by
application of any prepayments) of principal with respect to the Loans and
other outstanding Debt during such period, plus (c) taxes of the Borrower and
its Consolidated Subsidiaries paid or payable in cash during such period, plus
(d) the scheduled amount paid or payable by the Borrower and its Consolidated
Subsidiaries during such period on account of Capital Expenditures.

         "Consolidated Interest Expense" means, for any period, all interest on
Debt of the Borrower and its Consolidated Subsidiaries paid in cash during such
period, including the interest portion of payments under Capital Lease
Obligations.

         "Consolidated Net Income" means, for any period, the net income (or
loss) of the Borrower and its Consolidated Subsidiaries for such period,
determined on a consolidated basis in accordance with GAAP.

         "Consolidated Subsidiary" means, with respect to any Person, any
Subsidiary the financial attributes of which would be consolidated with those
of such Person in the consolidated financial statements of such Person in
accordance with GAAP.

         "Continue", "Continuation" and "Continued" shall refer to the
continuation pursuant to Section 2.6 of a Eurodollar Loan as a Eurodollar Loan
of the same Type from one Interest Period to the next Interest Period.

         "Contract Rate" means as specified in Section 13.12(a).

         "Contributed Capital" means, as to any Person and as of any date of
determination, the sum of (a) all equity contributions then made in cash or
previously made in cash to such Person (including equity contributed on or
before the Closing Date), minus (b) all Restricted Payments (in any form) then
made or previously made by such Person to or for the benefit of any other
Person.

         "Convert", "Conversion" and "Converted" shall refer to a conversion
pursuant to Section 2.6 or Article 4 of one Type of Loan into the other Type of
Loan.

         "Current Date" means (a) a date occurring no more than 30 days prior
to the Closing Date or other relevant date as may be specified herein (as
applicable) or (b) such earlier date which is acceptable to the Administrative
Agent.

CREDIT AGREEMENT - Page 9

<PAGE>   17

         "Debt" means as to any Person at any time (without duplication): (a)
all indebtedness, liabilities and obligations of such Person for borrowed
money, (b) all indebtedness, liabilities and obligations of such Person
evidenced by bonds, notes, debentures or other similar instruments, (c) all
indebtedness, liabilities and obligations of such Person to pay the deferred
purchase price of property or services, except trade accounts payable of such
Person arising in the ordinary course of business that are not past due by more
than 90 days, (d) all Capital Lease Obligations of such Person, (e) all Debt of
others Guaranteed by such Person, (f) all indebtedness, liabilities and
obligations secured by a Lien existing on Property owned by such Person,
whether or not the indebtedness, liabilities or obligations secured thereby
have been assumed by such Person or are non-recourse to such Person, (g) all
reimbursement obligations of such Person (whether contingent or otherwise) in
respect of letters of credit, bankers' acceptances, surety or other bonds and
similar instruments, (h) all indebtedness, liabilities and obligations of such
Person to redeem or retire shares of Capital Stock of such Person, (i) all
indebtedness, liabilities and obligations of such Person under Interest Rate
Protection Agreements, and (j) all indebtedness, liabilities and obligations of
such Person in respect of unfunded vested benefits under any pension plans.

         "Debt Service Coverage Ratio" means, as of the end of any calendar
quarter, the ratio of (a) Annualized EBITDA for the period ended as of the end
of such calendar quarter, exclusive of EBITDA attributable to tower sales, to
(b) the sum of (i) Consolidated Interest Expense for the four calendar quarter
period ended as of the end of such calendar quarter plus (ii) the aggregate
amount of all principal payments on Debt paid or due and owing during such four
calendar quarter period.

         "Default" means an Event of Default or the occurrence of an event or
condition which with notice or lapse of time or both would become an Event of
Default.

         "Default Rate" means, in respect of any principal of any Loan at all
times during which any Default has occurred and is continuing or in respect of
any other amount payable by the Borrower under this Agreement or any other Loan
Document which is not paid when due (whether at stated maturity, by
acceleration or otherwise), a rate per annum during the period of such Default
or during the period commencing on the due date of such other amount until such
other amount is paid in full, respectively, equal to the lesser of (a) the sum
of three percent (3.00%) plus the Base Rate as in effect from time to time plus
the Applicable Margin for Base Rate Loans or (b) the Maximum Rate; provided,
however, that if such amount in default is principal of a Eurodollar Loan and
the due date is a day other than the last day of an Interest Period therefor,
the "Default Rate" for such principal shall be, for the period from and
including the due date and to but excluding the last day of the Interest Period
therefor, the lesser of the rate per annum equal to (i) the sum of three
percent (3.00%) plus the interest rate for such Eurodollar Loan for such
Interest Period as provided in clause (ii) of Section 2.4(a) hereof or (ii) the
Maximum Rate and, thereafter, the rate provided for above in this definition.

         "Dollars" and "$" mean lawful money of the U.S.

         "EBITDA" means, for any period, without duplication, the sum of the
following for the Borrower and its Consolidated Subsidiaries for such period
determined on a consolidated basis in accordance with GAAP: (a) Adjusted Net
Income, plus (b) Consolidated Interest Expense, plus (c)

CREDIT AGREEMENT - Page 10

<PAGE>   18

income and franchise taxes to the extent deducted in determining Adjusted Net
Income, plus (d) depreciation and amortization expense and other non-cash,
non-tax items to the extent deducted in determining Adjusted Net Income, minus
(e) non-cash income (or losses) to the extent included in determining Adjusted
Net Income.

         "Eligible Assignee" means (a) any Lender or Affiliate of a Lender, (b)
any commercial bank, savings and loan association, savings bank, finance
company, insurance company, pension fund, mutual fund or other financial
institution (whether a corporation, partnership or other entity) which has been
approved by the Administrative Agent as a Lender under this Agreement or (c)
any Approved Fund; provided, however, that (i) Eligible Assignee shall not
include any Affiliate of the Borrower and (ii) Eligible Assignee shall not
include any business competitor of the Borrower or any Operating Subsidiary of
the Borrower engaged in the same line of business as the Borrower or any
Operating Subsidiary of the Borrower, respectively, except after the occurrence
and during the continuance of an Event of Default.

         "Environmental Law" means any federal, state, provincial, local or
foreign law, statute, code or ordinance, principle of common law, rule or
regulation, as well as any Permit, order, decree, judgment or injunction
issued, promulgated, approved or entered thereunder, relating to pollution or
the protection, cleanup or restoration of the environment or natural resources,
or to the public health or safety, or otherwise governing the generation, use,
handling, collection, treatment, storage, transportation, recovery, recycling,
discharge or disposal of Hazardous Materials, including, without limitation as
to U.S. laws, the Comprehensive Environmental Response, Compensation and
Liability Act of 1980, 42 U.S.C. Section 9601 et seq., the Superfund Amendment
and Reauthorization Act of 1986, 99-499, 100 Stat. 1613, the Resource
Conservation and Recovery Act of 1976, 42 U.S.C. Section 6901 et seq., the
Occupational Safety and Health Act, 29 U S.C. Section 651 et seq., the Clean
Air Act, 42 U.S.C. Section 7401 et seq., the Clean Water Act, 33 U.S.C. Section
1251 et seq., the Emergency Planning and Community Right to Know Act, 42 U.S.C.
Section 11001 et seq., the Federal Insecticide, Fungicide and Rodenticide Act,
7 U.S.C. Section 136 et seq., and the Toxic Substances Control Act, 15 U.S.C.
Section 2601 et seq., and any state or local counterparts.

         "Environmental Liabilities" means, as to any Person, all liabilities,
obligations, responsibilities, Remedial Actions, losses, damages, punitive
damages, consequential damages, treble damages, costs and expenses (including,
without limitation, all reasonable fees, disbursements and expenses of counsel,
expert and consulting fees and costs of investigation and feasibility studies),
fines, penalties, sanctions and interest incurred as a result of any claim or
demand, by any Person, whether based in contract, tort, implied or express
warranty, strict liability or criminal, penal or civil statute, including,
without limitation, any Environmental Law, Permit, order or agreement with any
Governmental Authority or other Person, arising from environmental, health or
safety conditions or the Release or threatened Release of a Hazardous Material
into the environment.

         "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended from time to time, and the regulations and published interpretations
thereunder.

CREDIT AGREEMENT - Page 11

<PAGE>   19

         "ERISA Affiliate" means any corporation or trade or business which is
a member of a group of entities, organizations or employers of which a Loan
Party is also a member and which is treated as a single employer within the
meaning of Sections 414(b), (c), (m) or (o) of the Code.

         "Eurodollar Loans" means Loans that bear interest at rates based upon
the Eurodollar Rate or the Adjusted Eurodollar Rate.

         "Eurodollar Rate" means, for any Eurodollar Loan for any Interest
Period therefor, the rate per annum (rounded upwards, if necessary, to the
nearest 1/16 of 1%) appearing on Telerate Page 3750 (or any successor page) as
the London interbank offered rate for deposits in Dollars in the approximate
amount of the proposed Eurodollar Loan at approximately 11:00 a.m. (London
time) two Business Days prior to the first day of such Interest Period for a
term comparable to such Interest Period. If such rate ceases to be available
from Telerate News Service, the Eurodollar Rate shall be determined by the
Administrative Agent in good faith from another financial reporting service,
which service shall be reasonably acceptable to the Borrower.

         "Event of Default" has the meaning specified in Section 11.1.

         "Excess Cash Flow" means, for any fiscal year and without duplication,
EBITDA for such fiscal year minus (a) taxes payable in cash for such fiscal
year, (b) all principal and cash interest payments on Debt made during such
fiscal year whether optional, mandatory or scheduled payments, (c) Capital
Expenditures (but only to the extent paid in cash and not financed) made during
such fiscal year, and (d) the aggregate amount of dividends paid by the
Borrower to Holdings, and permitted to be paid by the Borrower to Holdings, in
accordance with clause (c) of Section 9.4.

         "Excess Proceeds Amount" means as specified in Section 2.7(a).

         "Exchange Act" means the Securities Exchange Act of 1934, as amended
(or any successor act), and the rules and regulations thereunder (or respective
successors thereto).

         "FCC" means the Federal Communications Commission and any successor
agency.

         "Federal Funds Rate" means, for any day, the rate per annum (rounded
upwards, if necessary, to the nearest one-sixteenth of one percent (1/16 of
1%)) equal to the weighted average of the rates on overnight Federal funds
transactions with members of the Federal Reserve System arranged by Federal
funds brokers on such day, as published by the Federal Reserve Bank of New York
on the Business Day next succeeding such day, provided that (a) if the day for
which such rate is to be determined is not a Business Day, the Federal Funds
Rate for such day shall be such rate on such transactions on the next preceding
Business Day as so published on the next succeeding Business Day and (b) if
such rate is not so published on such next succeeding Business Day, the Federal
Funds Rate for any day shall be the average rate which would be charged to the
Reference Bank on such day on such transactions as determined by the
Administrative Agent.

         "Former Members" means the former owners of membership interests in
the Original Borrower.

CREDIT AGREEMENT - Page 12

<PAGE>   20

         "GAAP" means generally accepted accounting principles, applied on a
consistent basis, as set forth in Opinions of the Accounting Principles Board
of the American Institute of Certified Public Accountants and/or in statements
of the Financial Accounting Standards Board and/or their respective successors
and which are applicable in the circumstances as of the date in question.
Accounting principles are applied on a "consistent basis" when the accounting
principles applied in a current period are comparable in all material respects
to those accounting principles applied in a preceding period.

         "Governmental Authority" means any nation or government, any state,
provincial or political subdivision thereof and any entity exercising
executive, legislative, judicial, regulatory or administrative functions of or
pertaining to government.

         "Governmental Requirement" means any law, statute, code, ordinance,
order, rule, regulation, judgment, decree, injunction, franchise, Permit,
certificate, license, authorization or other directive or requirement of any
federal, state, county, municipal, parish, provincial or other Governmental
Authority or any department, commission, board, court, agency or any other
instrumentality of any of them.

         "Gross Revenues" means, for any period, gross revenues, determined on
a consolidated basis, of the Borrower and its Consolidated Subsidiaries
determined in accordance with GAAP for such period.

         "Gross Up Lender" means any Lender which requests a payment from the
Borrower pursuant to Section 3.5, 4.1 or 4.6.

         "Guarantee" by any Person means any obligation, contingent or
otherwise, of such Person directly or indirectly guaranteeing any Debt or other
obligation of any other Person and, without limiting the generality of the
foregoing, any indebtedness, liability or obligation, direct or indirect,
contingent or otherwise, of such Person (a) to purchase or pay (or advance or
supply funds for the purchase or payment of) such Debt or other obligation
(whether arising by virtue of partnership arrangements, by agreement to
keep-well, to purchase assets, goods, securities or services, to take-or- pay
or to maintain financial statement conditions or otherwise) or (b) entered into
for the purpose of assuring in any other manner the obligee of such Debt or
other indebtedness, liability or obligation as to the payment thereof or to
protect the obligee against loss in respect thereof (in whole or in part),
provided that the term Guarantee shall not include endorsements for collection
or deposit in the ordinary course of business. The term "Guarantee" used as a
verb has a corresponding meaning. The amount of any Guarantee shall be deemed
to be an amount equal to the stated or determinable amount of the primary
obligation in respect of which such Guarantee is made or, if not stated or
determinable, the maximum anticipated liability in respect thereof (assuming
such Person is required to perform thereunder).

         "Guarantors" means Holdings, each Subsidiary of Holdings, other than
Unrestricted Subsidiaries of Holdings, at any time existing, each Subsidiary of
the Borrower at any time existing and each other Person which has executed a
Guaranty (each individually a "Guarantor" and collectively the "Guarantors").

CREDIT AGREEMENT - Page 13

<PAGE>   21

         "Guaranty" means a guaranty agreement guaranteeing payment and
performance of the Obligations in form and substance satisfactory to the
Administrative Agent executed by a Guarantor in favor of the Administrative
Agent and the Lenders, and any and all amendments, modifications, supplements,
renewals, extensions or restatements thereof.

         "Hazardous Material" means any substance, product, liquid, waste,
pollutant, chemical, contaminant, insecticide, pesticide, gaseous or solid
matter, organic or inorganic matter, fuel, micro- organisms, ray, odor,
radiation, energy, vector, plasma, constituent or material which (a) is or
becomes listed, regulated or addressed under any Environmental Law or (b) is,
or is deemed to be, alone or in any combination, hazardous, hazardous waste,
toxic, a pollutant, a deleterious substance, a contaminant or a source of
pollution or contamination under any Environmental Law, including, without
limitation, asbestos, petroleum, underground storage tanks (whether empty or
containing any substance) and polychlorinated biphenyls.

         "Holdings" means as specified in the initial paragraph of this
Agreement.

         "Holdings Public Offering" means an initial public offering of the
common stock of Holdings providing net cash proceeds to Holdings of at least
$140,000,000.

         "Holdings Senior Notes" means senior discount notes due 2010
contemplated to be issued by Holdings that will yield gross proceeds at
issuance of approximately $156,000,000, which notes shall be unsecured and
shall otherwise be in form and substance satisfactory to, and approved in
writing (subsequent to the Closing Date) by, the Administrative Agent and the
Required Lenders.

         "Holdings Senior Notes Documents" means any and all agreements,
documents and instruments now or hereafter evidencing or governing the Holdings
Senior Notes and includes, without limitation, the Holdings Senior Notes
Indenture.

         "Holdings Senior Notes Event of Default" means an "Event of Default"
as such term is defined in the Holdings Senior Note Indenture.

         "Holdings Senior Notes Indenture" means an indenture in form and
substance satisfactory to, and approved in writing (subsequent to the Closing
Date) by, the Administrative Agent and the Required Lenders which governs the
Holdings Senior Notes.

         "Insurance Recovery" means, with respect to any Property of any Loan
Party and any single occurrence or related occurrences with respect thereto,
the receipt or constructive receipt by such Person, or the payment by an
insurance company to the Administrative Agent, of proceeds of any such Property
or casualty insurance.

         "Intellectual Property" means any U.S. or foreign patents, patent
applications, trademarks, trade names, service marks, brand names, logos and
other trade designations (including unregistered names and marks), trademark
and service mark registrations and applications, copyrights and copyright
registrations and applications, inventions, invention disclosures, protected
formulae, formulations, processes, methods, trade secrets, computer software,
computer programs and source

CREDIT AGREEMENT - Page 14

<PAGE>   22

codes, manufacturing research and similar technical information, engineering
know-how, customer and supplier information, assembly and test data drawings or
royalty rights.

         "Interest Period" means, with respect to any Eurodollar Loan, each
period commencing on the date such Loan is made or Converted from a Base Rate
Loan or (if Continued) the last day of the next preceding Interest Period with
respect to such Loan, and ending on the numerically corresponding day in the
first, second, third or sixth calendar month thereafter, as the Borrower may
select as provided in Section 2.9 hereof, except that each such Interest Period
which commences on the last Business Day of a calendar month (or on any day for
which there is no numerically corresponding day in the appropriate subsequent
calendar month) shall end on the last Business Day of the appropriate
subsequent calendar month. Notwithstanding the foregoing: (a) each Interest
Period which would otherwise end on a day which is not a Business Day shall end
on the next succeeding Business Day (or, if such succeeding Business Day falls
in the next succeeding calendar month, on the next preceding Business Day); (b)
any Interest Period which would otherwise extend beyond the Maturity Date shall
end on the Maturity Date; (c) no more than five Interest Periods for Eurodollar
Loans shall be in effect at the same time; (d) no Interest Period shall have a
duration of less than one month and, if the Interest Period for any Eurodollar
Loans would otherwise be a shorter period, such Loans shall not be available
hereunder; and (e) no Interest Period for a Loan may commence before, and end
after, any principal payment date unless, after giving effect thereto, the
aggregate principal amount of the Eurodollar Loans having Interest Periods that
end after such principal payment date shall be equal to or less than the amount
of the applicable Loans scheduled to be outstanding hereunder after such
principal payment date.

         "Interest Rate Protection Agreements" means, with respect to the
Borrower, an interest rate swap, cap or collar agreement or similar arrangement
between the Borrower and one or more Lenders or other counterparties providing
for the transfer or mitigation of interest rate risks either generally or under
specified contingencies.

         "Investments" means as specified in Section 9.5.

         "Lender" and "Lenders" means as specified in the initial paragraph of
this Agreement.

         "Lien" means, with respect to any Property, any mortgage or deed of
trust, pledge, hypothecation, assignment, deposit arrangement, security
interest, tax lien, financing statement, pledge, charge, hypothecation or other
lien, charge, easement (other than any easement not materially impairing
usefulness), encumbrance, preference, priority or other security agreement or
preferential arrangement of any kind or nature whatsoever on or with respect to
such Property (including, without limitation, any conditional sale or other
title retention agreement having substantially the same economic effect as any
of the foregoing).

         "Loan Documents" means this Agreement, the Notes, the Security
Documents, the Administrative Agent's Letter, the Consents and Agreements and
all other agreements, documents, instruments and certificates now or hereafter
executed and/or delivered pursuant to or in connection with any of the
foregoing, and any and all amendments, modifications, supplements, renewals,
extensions or restatements thereof.

CREDIT AGREEMENT - Page 15

<PAGE>   23

         "Loan Party" means any of Holdings, the Borrower, any Operating
Subsidiary, any Subsidiary of Holdings other than an Unrestricted Subsidiary,
any Subsidiary of the Borrower, any Guarantor or any Person who grants a Lien
on any Property to secure the payment or performance of the Obligations or any
portion thereof, and "Loan Parties" means all of such Persons.

         "Loans" means the Tranche A Loans, the Tranche B Loans and the Tranche
C Loans, and "Loan" means any of such loans.

         "Material Adverse Effect" means any event, development or circumstance
that has had or could reasonably be expected to have a material adverse effect
on (a) the business, assets, financial condition, results of operations or
prospects of Holdings and its Subsidiaries taken as a whole, the Borrower and
its Subsidiaries taken as a whole, (b) the validity or enforceability of any of
the Loan Documents or the Liens created or purported to be created thereby or
the rights and/or remedies of the Administrative Agent and the Lenders
thereunder, (c) the ability of any Loan Party to pay and perform its
indebtedness, liabilities and/or obligations under any of the Loan Documents,
or (d) the value of Collateral available to the Administrative Agent and the
Lenders after giving effect to Liens in favor of other Persons.

         "Material Contracts" means, as to any Loan Party, (a) any Sprint
Agreement and (b) any supply, purchase, service, employment, tax, indemnity,
shareholder or other agreement or contract for which the aggregate amount or
value of services performed or to be performed for or by, or funds or other
Property transferred or to be transferred to or by, any such Person to such
agreement or contract, or by which any such Person or any of its Properties is
otherwise bound, during any fiscal year of the Borrower exceeds $1,000,000 (or
the equivalent amount in any currency) and any and all amendments,
modifications, supplements, renewals or restatements thereof.

         "Maturity Date" means the earlier to occur of (a) August 8, 2007 or
(b) the fifth anniversary of the Amortization Commencement Date.

         "Maximum Rate" means, with respect to any Lender, the maximum
non-usurious interest rate or an amount computed in reference to such rate (as
applicable), if any, that any time or from time to time may be contracted for,
taken, reserved, charged or received with respect to the particular Obligations
as to which such rate is to be determined, payable to such Lender pursuant to
this Agreement or any other Loan Document, under laws applicable to such Lender
which are presently in effect or, to the extent allowed by law, under such
applicable laws which may hereafter be in effect and which allow a higher
maximum non-usurious interest rate than applicable laws now allow. The Maximum
Rate shall be calculated in a manner that takes into account any and all fees,
payments and other charges in respect of the Loan Documents that constitute
interest under applicable law. Each change in any interest rate provided for
herein based upon the Maximum Rate resulting from a change in the Maximum Rate
shall take effect without notice to the Borrower at the time of such change in
the Maximum Rate.

         "Monthly Date" means the last day of each month of each year the first
of which shall be March 31, 2000.

CREDIT AGREEMENT - Page 16

<PAGE>   24

         "Mortgage" means a mortgage, deed of trust or other appropriate
agreement, document or instrument evidencing or creating a Lien on real
Property (and any related personal Property) as security for the Obligations or
any portion thereof in form and substance satisfactory to the Administrative
Agent executed by any Loan Party in favor of the Administrative Agent for the
benefit of the Administrative Agent and the Lenders, and any and all
amendments, modifications, supplements, renewals, extensions or restatements
thereof.

         "Mortgaged Properties" means Properties in which a Lien has been
granted or purported to be granted pursuant to a Mortgage.

         "Multiemployer Plan" means a multiemployer plan defined as such in
Section 3(37) of ERISA to which contributions have been made by or are required
from any Loan Party or any ERISA Affiliate since 1974 and which is covered by
Title IV of ERISA.

         "Net Proceeds" means, with respect to any Asset Disposition, (a) the
gross amount of cash received by any Loan Party from such Asset Disposition,
minus (b) the amount, if any, of all taxes paid or payable by such Loan Party
directly resulting from such Asset Disposition (including the amount, if any,
estimated by such Loan Party in good faith at the time of such Asset
Disposition for taxes payable by such Loan Party on or measured by net income
or gain resulting from such Asset Disposition), minus (c) the reasonable
out-of-pocket costs and expenses incurred by such Loan Party in connection with
such Asset Disposition (including reasonable brokerage fees paid to a Person
other than an Affiliate of a Loan Party) excluding any fees or expenses paid to
an Affiliate of a Loan Party, minus (d) amounts applied to the repayment of
indebtedness (other than the Obligations) secured by any Permitted Lien (if
any) on the Property subject to the Asset Disposition. "Net Proceeds" with
respect to any Asset Disposition shall also include proceeds (after deducting
any amounts specified in clauses (b), (c) and (d) of the preceding sentence) of
insurance with respect to any actual or constructive loss of Property, an
agreed or compromised loss of Property or the taking of any Property under the
power of eminent domain and condemnation awards and awards in lieu of
condemnation for the taking of Property under the power of eminent domain. "Net
Proceeds" means, with respect to the Holdings Senior Notes and without
duplication, (i) the gross amount of cash or cash equivalents plus the gross
value of all other consideration received by Holdings or any of its
Subsidiaries from the issuance of the Holdings Senior Notes, minus (ii) the
out-of-pocket costs and expenses incurred by Holdings in connection with such
issuance of the Holdings Senior Notes (including any underwriting fees)
excluding any fees or expenses paid to an Affiliate of Holdings which are in
excess of those that would be paid or payable in connection with an arms'
length transaction with a Person who is not an Affiliate of Holdings.

         "New Areas" means, as of any date of determination, those portions of
the Service Area not covered by the then-existing Build-out Plan that Sprint
PCS or the Borrower decides should be built- out.

         "Nortel Networks" means Nortel Networks Inc., a Delaware corporation.

         "Nortel Networks Equipment" means all hardware, software and equipment
(including fixtures) manufactured, sold or otherwise provided to the Borrower
or any other Subsidiary of the

CREDIT AGREEMENT - Page 17

<PAGE>   25

Borrower by Nortel Networks and/or Nortel Networks Corporation, including,
without limitation, all equipment sold to the Borrower or a Subsidiary of the
Borrower pursuant to the Supply Agreement and all Nortel Networks Software.

         "Nortel Networks Goods and Services" means (a) Nortel Networks
Equipment and related software (including Nortel Networks Software), (b) sales,
installation and commissioning of Nortel Networks Equipment and related
software (including Nortel Networks Software), and (c) project management,
system design and services performed by personnel of Nortel Networks and/or
Nortel Networks Corporation.

         "Nortel Networks Software" means any and all software sold or licensed
by Nortel Networks and/or Nortel Networks Corporation to the Borrower or any
Subsidiary of the Borrower, including, without limitation, all source code and
object code and all manuals and other documentation relating thereto and each
copy thereof regardless of the media in which they are stored.

         "Noteholders" means the holders of the Holdings Senior Notes.

         "Notes" means the Tranche A Notes, the Tranche B Notes and the Tranche
C Notes, in the form of Exhibit B-1, Exhibit B-2 and Exhibit B-3, respectively,
hereto, made by the Borrower evidencing the Loans and any and all amendments,
modifications, supplements, renewals, extensions or restatements thereof and
all substitutions therefor (including promissory notes issued by the Borrower
pursuant to Section 13.8), and "Note" means any such promissory note.

         "Notice of Borrowing" means as specified in Section 2.9.

         "Obligations" means any and all (a) indebtedness, liabilities and
obligations of the Borrower or any other Loan Party to the Administrative Agent
and the Lenders, or any of them, evidenced by and/or arising pursuant to any of
the Loan Documents (including, without limitation, this Agreement and the
Notes), now existing or hereafter arising, whether direct, indirect, related,
unrelated, fixed, contingent, liquidated, unliquidated, joint, several or joint
and several, including, without limitation, (i) the obligations of the Borrower
or any other Loan Party to repay the Loans, to pay interest on the Loans
(including, without limitation, interest accruing after any, if any,
bankruptcy, insolvency, reorganization or other similar filing) and to pay all
fees, indemnities, costs and expenses (including attorneys' fees) provided for
in the Loan Documents and (ii) the indebtedness constituting the Loans and such
interest, fees, indemnities, costs and expenses, and (b) indebtedness,
liabilities and obligations of the Borrower or any other Loan Party under any
and all Interest Rate Protection Agreements that it may enter into with any
Lender with the prior written consent of the Administrative Agent and the
Required Lenders.

         "Operating Assets" means the "Operating Assets" as such term is
defined or used in any Sprint Management Agreement, which term includes the
assets owned by the Borrower or a Subsidiary of the Borrower constituting a
part of the Service Area Network.

CREDIT AGREEMENT - Page 18

<PAGE>   26

         "Operating Lease" means, as to any Person, a lease of (or other
agreement conveying the right to use) real and/or personal Property, provided
that the obligations thereunder are not required to be capitalized on a balance
sheet of such Person under GAAP.

         "Operating Subsidiary" means Alamosa Texas or Alamosa Wisconsin, and
"Operating Subsidiaries" means both of such entities.

         "Original Administrative Agent" means as specified in Recital A.

         "Original Borrower" means as specified in Recital A.

         "Original Credit Agreement" means as specified in Recital A.

         "Original Lenders" means as specified in Recital A.

         "Original Loans" means the "Loans" as such term is defined in the
Original Credit Agreement.

         "Original Obligations" means the "Obligations" as such term is defined
in the Original Credit Agreement.

         "Original Tranche A Loans" means the "Tranche A Loans" as such term is
defined in the Original Credit Agreement.

         "Original Tranche B Loans" means the "Tranche B Loans" as such term is
defined in the Original Credit Agreement.

         "Original Tranche C Loans" means the "Tranche C Loans" as such term is
defined in the Original Credit Agreement.

         "Payor" means as specified in Section 3.4.

         "PBGC" means the Pension Benefit Guaranty Corporation or any entity
succeeding to all or any of its functions under ERISA.

         "PCS" means a radio communication system authorized under the rules
for broadband personal communications services designated as Subpart E of Part
24 of the FCC's rules, including the network, marketing, distribution, sales,
customer interface and operations functions relating thereto.

         "PCS Licenses" means the PCS license(s) issued by the FCC for the BTAs
constituting the Service Area.

         "PCS Spectrum" means the range of frequencies that Sprint PCS is
authorized to use under the PCS Licenses held by Sprint PCS.

CREDIT AGREEMENT - Page 19

<PAGE>   27

         "Pension Plan" means an employee pension benefit plan as defined in
Section 3(2) of ERISA (including a Multiemployer Plan) which is subject to the
funding requirements under Section 302 of ERISA or Section 412 of the Code, in
whole or in part, and which is maintained or contributed to currently or at any
time within the six years immediately preceding the Closing Date or, in the
case of a Multiemployer Plan, at any time since September 2, 1974, by any Loan
Party or any ERISA Affiliate for employees of any Loan Party or any ERISA
Affiliate.

         "Permit" means any permit, certificate, approval, order, PCS License,
license, right-of-way (whether an easement, contract or agreement in any form)
or other authorization.

         "Permitted Holders" means the shareholders of Holdings identified in
Schedule 1.1(a) hereto.

         "Permitted Liens" mean:

                  (a) Liens disclosed on Schedule 1.1(b) hereto;

                  (b) Liens securing the Obligations in favor of the
         Administrative Agent (for the benefit of the Administrative Agent and
         the Lenders) pursuant to the Loan Documents;

                  (c) Encumbrances consisting of easements, rights-of-way,
         zoning restrictions or other restrictions on the use of real Property
         or imperfections to title that do not (individually or in the
         aggregate) materially affect the value of the Property encumbered
         thereby or materially impair the ability of any Loan Party to use such
         Property in its businesses, and none of which is violated in any
         material respect by existing or proposed structures or land use;

                  (d) Liens for taxes, assessments or other governmental
         charges that are not delinquent or which are being contested in good
         faith by appropriate proceedings, which proceedings have the effect of
         preventing the forfeiture or sale of the Property subject to such
         Liens, and for which adequate reserves have been established;

                  (e) Liens of mechanics, materialmen, warehousemen, carriers,
         landlords or other similar statutory Liens securing obligations that
         are not yet due and are incurred in the ordinary course of business or
         which are being contested in good faith by appropriate proceedings,
         which proceedings have the effect of preventing the forfeiture or sale
         of the Property subject to such Liens, and for which adequate reserves
         have been established;

                  (f) Liens resulting from good faith deposits to secure
         payment of worker's compensation or other social security programs or
         to secure the performance of tenders, statutory obligations, surety
         and appeal bonds, bids, contracts (other than for payment of Debt) or
         leases, all in the ordinary course of business;

                  (g) Purchase-money Liens on any Property hereafter acquired
         or the assumption after the Closing Date of any Lien on Property
         existing at the time of such acquisition (and not created in
         contemplation of such acquisition), or a Lien incurred after the
         Closing Date

CREDIT AGREEMENT - Page 20

<PAGE>   28

         in connection with any conditional sale or other title retention
         agreement or Capital Lease Obligation; provided that:

                            (i) any Property subject to the foregoing is
                  acquired by the applicable Loan Party in the ordinary course
                  of its respective business and the Lien on the Property
                  attaches concurrently or within 90 days after the acquisition
                  thereof;

                            (ii) the Debt secured by any Lien so created,
                  assumed or existing shall not exceed the lesser of the cost
                  or fair market value at the time of acquisition of the
                  Property covered thereby (inclusive of the cost of
                  engineering, furnishing and installation services directly
                  relating to such Property) and shall not be less than 75% of
                  the amortized value of the Property acquired with the
                  proceeds of such Debt;

                           (iii) each such Lien shall attach only to the
                  Property so acquired and the proceeds thereof; and

                            (iv) the Debt secured by all such Liens, when
                  aggregated with the Debt secured by all purchase-money Liens
                  and all Liens in connection with any conditional sale or
                  other title retention agreement or Capital Lease Obligation
                  existing as of the Closing Date or at any other time, shall
                  not exceed $15,000,000 at any time outstanding in the
                  aggregate;

                  (h) Liens attaching to the Capital Stock of Unrestricted
         Subsidiaries of Holdings securing Debt of Holdings or its Unrestricted
         Subsidiaries; and

                  (i) Any extension, renewal or replacement of any of the
         foregoing, provided that Liens permitted hereunder shall not be
         extended or spread to cover any additional indebtedness or Property;

provided, however, that (A) none of the Permitted Liens (except those in favor
of the Administrative Agent) may attach or relate to the Capital Stock of or
any other ownership interest in the Borrower or any of its Subsidiaries and (B)
except for the Liens disclosed on Schedule 1.1(b) hereto which are expressly
identified as constituting purchase money Liens, none of the Permitted Liens
referred to in clause (a) preceding may have a priority equal or prior to the
Liens in favor of the Administrative Agent as security for the Obligations.

         "Permitted Third-Party Expenses" means (a) amounts paid to vendors of
equipment and services (including sales taxes), including Nortel Networks, for
the construction of the Service Area Network, (b) Service Area Network site
acquisition costs excluding any lease costs, but including civil engineering
work, site preparation and costs of power connection, (c) costs of establishing
physical interconnection with the local public switched telephone network, and
(d) microwave relocation costs associated with construction of the Service Area
Network, whether paid directly or reimbursed to third parties who previously
performed the relocation, provided, however, that such microwave relocation
costs includable as Permitted Third-Party Expenses shall not exceed $8,000,000
in the aggregate.

CREDIT AGREEMENT - Page 21

<PAGE>   29

         "Permitted Third-Party Expenses Borrowing Base" means, at any time as
determined by the Administrative Agent in accordance with Section 2.1(f), an
amount equal to 50% of the amount paid to Nortel Networks by the Borrower for
Nortel Networks Goods and Services for the Service Area Network (including any
amounts to be paid with the proceeds of an Advance requested on the date of the
Permitted Third-Party Expenses Borrowing Base Report).

         "Permitted Third-Party Expenses Borrowing Base Report" means a report
in substantially the form of Exhibit E attached hereto properly completed and
certified by a Responsible Officer of the Borrower to the satisfaction of the
Administrative Agent which specifies the Permitted Third-Party Expenses
Borrowing Base as calculated as of the date of the report.

         "Person" means any individual, corporation, trust, association,
company, partnership, joint venture, limited liability company, joint stock
company, Governmental Authority or other entity.

         "Plan" means any employee benefit plan as defined in Section 3(3) of
ERISA established or maintained or contributed to by any Loan Party or any
ERISA Affiliate, including any Pension Plan.

         "Principal Office" means the principal office of the Administrative
Agent in Richardson, Texas, presently located at 2221 Lakeside Blvd.,
Richardson, Texas 75082.

         "Prohibited Transaction" means any transaction set forth in Section
406 of ERISA or Section 4975 of the Code.

         "Property" means property and/or assets of all kinds, real, personal
or mixed, tangible or intangible (including, without limitation, all rights
relating thereto), whether owned or acquired on or after the Closing Date.

         "Quarterly Date" means the last day of each March, June, September and
December of each year, the first of which shall be March 31, 2000.

         "Receivables" means, as at any date of determination thereof, each and
every "account" as such term is defined in the UCC and includes, without
limitation, the unpaid portion of the obligation, as stated on the respective
invoice, or, if there is no invoice, other writing, of a customer of any Loan
Party in respect of services rendered by any Loan Party.

         "Reference Bank" means Citibank, N.A.

         "Register" means as specified in Section 13.8(d).

         "Registered Note" means as specified in Section 2.2(b).

         "Registered Note Register" means as specified in Section 13.8(h).

         "Regulation D" means Regulation D of the Board of Governors of the
Federal Reserve System as the same may be amended or supplemented from time to
time.

CREDIT AGREEMENT - Page 22

<PAGE>   30

         "Regulatory Change" means, with respect to any Lender, any change
after the Closing Date in any U.S. federal or state or foreign laws or
regulations (including Regulation D) or the adoption or making after such date
of any interpretations, directives or requests applying to a class of lenders
including such Lender of or under any U.S. federal or state or foreign laws or
regulations (whether or not having the force of law) by any Governmental
Authority charged with the interpretation or administration thereof.

         "Release" means, as to any Person, any release, spill, emission,
leaking, pumping, injection, deposit, discharge, disposal, dispersement,
leaching or migration of Hazardous Materials into the indoor or outdoor
environment or into or out of Property owned by such Person, including, without
limitation, the movement of Hazardous Materials through or in the air, soil,
surface water or ground water.

         "Remedial Action" means all actions required to (a) cleanup, remove,
respond to, treat or otherwise address Hazardous Materials in the indoor or
outdoor environment, (b) prevent the Release or threat of Release or minimize
the further Release of Hazardous Materials so that they do not migrate or
endanger or threaten to endanger public health or welfare or the indoor or
outdoor environment, (c) perform studies and investigations on the extent and
nature of any actual or suspected contamination, the remedy or remedies to be
used or health effects or risks of such contamination, or (d) perform
post-remedial monitoring, care or remedy of a contaminated site.

         "Reportable Event" means any of the events set forth in Section
4043(b) of ERISA other than any such event for which the 30-day notice
requirement has been waived in regulations issued by the PBGC.

         "Required Lenders" means, at any date of determination, Lenders
holding at least two-thirds (in Dollar amount) of the sum of (a) the aggregate
outstanding principal amount of the Loans, plus (b) the aggregate principal
amount of the outstanding Commitments.

         "Required Payment" means as specified in Section 3.4.

         "Reorganization Transactions" means as specified in Recital B.

         "Reserve Requirement" means, for any Eurodollar Loan of any Lender for
any Interest Period therefor, the maximum rate at which reserves (including any
marginal, supplemental or emergency reserves) are required to be maintained
during such Interest Period under any regulations of the Board of Governors of
the Federal Reserve System (or any successor) by such Lender for deposits
exceeding $1,000,000 against "Eurocurrency Liabilities" as such term is used in
Regulation D. Without limiting the effect of the foregoing, the Reserve
Requirement shall reflect any other reserves required to be maintained by such
Lenders by reason of any Regulatory Change against (a) any category of
liabilities which includes deposits by reference to which the Eurodollar Rate
or the Adjusted Eurodollar Rate is to be determined or (b) any category of
extensions of credit or other assets which include Eurodollar Loans.

CREDIT AGREEMENT - Page 23

<PAGE>   31

         "Responsible Officer" means, as to any Loan Party, the chief executive
officer, the president, any vice president, the chief financial officer, the
chief operating officer or the treasurer of such Person.

         "Restricted Payment" means (a) any dividend or other distribution
(whether in cash, Property or obligations), direct or indirect, on account of
(or the setting apart of money for a sinking or other analogous fund for) any
shares of any class of Capital Stock of the Borrower or any of its Subsidiaries
now or hereafter outstanding, except a dividend payable solely in shares of
that class of stock to the holders of that class; (b) any redemption,
conversion, exchange, retirement, sinking fund or similar payment, purchase or
other acquisition for value, direct or indirect, of any shares of any class of
Capital Stock of the Borrower or any of its Subsidiaries now or hereafter
outstanding; (c) any payment or prepayment of principal of, premium, if any, or
interest on, or any redemption, conversion, exchange, purchase, retirement or
defeasance of, or payment with respect to, any subordinated debt; (d) any loan,
advance or payment to any officer, director or shareholder of the Borrower or
any of its Subsidiaries (other than a shareholder consisting of the Borrower or
a Wholly- Owned Subsidiary of the Borrower), exclusive of reasonable
compensation paid to officers or directors paid in the ordinary course of
business; and (e) any payment made to retire, or to obtain the surrender of,
any outstanding warrants, options or other rights to acquire shares of any
class of Capital Stock of the Borrower or any of its Subsidiaries now or
hereafter outstanding.

         "Security Agreements" means security agreements, pledge agreements,
securities pledge agreements and other agreements, documents or instruments
evidencing or creating a Lien as security for the Obligations or any portion
thereof in form and substance satisfactory to the Administrative Agent executed
by any Loan Party, in favor of the Administrative Agent for the benefit of the
Administrative Agent and the Lenders, and any such agreement, document or
instrument subsequently executed in accordance or connection with this
Agreement or any other Loan Document, and any and all amendments,
modifications, supplements, renewals, extensions or restatements thereof.

         "Security Documents" means the Security Agreements and the Mortgages,
as they may be amended, modified, supplemented, renewed, extended or restated
from time to time, and any and all other agreements, deeds of trust, mortgages,
chattel mortgages, security agreements, pledges, guaranties, assignments of
proceeds, assignments of income, assignments of contract rights, assignments of
partnership interests, assignments of royalty interests, assignments of
performance or other collateral assignments, subordination agreements,
undertakings and other agreements, documents, instruments and financing
statements now or hereafter executed and/or delivered by any Person in
connection with or as security or assurance for the payment or performance of
the Obligations or any part thereof.

         "Senior Debt" means, as of any date of determination and with respect
to any Person and its Consolidated Subsidiaries, the remainder of (a) Total
Debt minus (b) the aggregate principal amount of all Approved Subordinated Debt
outstanding, determined on a consolidated basis in accordance with GAAP.

CREDIT AGREEMENT - Page 24

<PAGE>   32

         "Service Area" means the BTAs described on the Service Area Exhibit to
the Sprint Management Agreements and as identified (by number and otherwise) on
Schedule 1.1(c) hereto, except that the term does not include any BTAs not
disclosed on Schedule 1.1(c) or any New Areas that the Borrower chooses not to
build out.

         "Service Area Network" means the network and business activities of
the Borrower and its Operating Subsidiaries managed by the Borrower and/or its
Operating Subsidiaries under the Sprint Management Agreements in the Service
Area under the PCS Licenses.

         "Solvent" means, with respect to any Person as of the date of any
determination, that on such date (a) the fair value of the Property of such
Person (both at fair valuation and at present fair saleable value) is greater
than the total liabilities, including, without limitation, contingent
liabilities, of such Person, (b) the present fair saleable value of the assets
of such Person is not less than the amount that will be required to pay the
probable liability of such Person on its debts as they become absolute and
matured, (c) such Person is able to realize upon its assets and pay its debts
and other liabilities, contingent obligations and other commitments as they
mature in the normal course of business, (d) such Person does not intend to,
and does not believe that it will, incur debts or liabilities beyond such
Person's ability to pay as such debts and liabilities mature, and (e) such
Person is not engaged in business or a transaction, and is not about to engage
in business or a transaction, for which such Person's Property would constitute
unreasonably small capital after giving due consideration to current and
anticipated future capital requirements and current and anticipated future
business conduct and the prevailing practice in the industry in which such
Person is engaged. In computing the amount of contingent liabilities at any
time, such liabilities shall be computed at the amount which, in light of the
facts and circumstances existing at such time, represents the amount that can
reasonably be expected to become an actual or matured liability.

         "Sprint Agreements" means the Sprint Management Agreements, the Sprint
Services Agreements, the Sprint Trademark and Service Mark License Agreements
and the Sprint Spectrum Trademark and Service Mark License Agreements.

         "Sprint Management Agreement (Alamosa Texas)" means that certain
Sprint PCS Management Agreement dated as of December 23, 1999 executed by
Sprint Spectrum, WirelessCo, L.P., Cox Communications PCS, L.P., Cox PCS
License, LLC, SprintCom, Inc., Sprint Communications Company, L.P. and the
Original Borrower, as amended by that certain Addendum I to Sprint PCS
Management Agreement dated as of December 23, 1999, and that certain Addendum
II to Sprint PCS Management Agreement dated as of February 3, 2000, and as
assigned and transferred to and assumed by Alamosa Texas pursuant to that
certain Notice, Consent, Transfer and Assignment dated as of February 3, 2000,
but effective as of February 8, 2000, and any documents incorporated by
reference in said agreement.

         "Sprint Management Agreement (Alamosa Wisconsin)" means that certain
Sprint PCS Management Agreement dated as of December 6, 1999 executed by Sprint
Spectrum, WirelessCo, L.P., Sprint Communications Company, L.P. and Alamosa
Wisconsin, as amended by that certain Addendum I to Sprint PCS Management
Agreement dated as of December 6, 1999, and that certain Addendum II to Sprint
PCS Management Agreement dated as of February 3, 2000,

CREDIT AGREEMENT - Page 25

<PAGE>   33

and any documents incorporated by reference in said agreement.

         "Sprint Management Agreements" means the Sprint Management Agreement
(Alamosa Texas) and the Sprint Management Agreement (Alamosa Wisconsin).

         "Sprint PCS" means any one or more of the following related parties
who are PCS License holders or signatories to any Sprint Agreement: Sprint
Spectrum, SprintCom, Inc., Sprint Communications Company, L.P., WirelessCo,
L.P., Cox Communications PCS, L.P., Cox PCS License, LLC and any affiliate of
any of the foregoing entities.

         "Sprint PCS Fees" means any fees payable to Sprint PCS by the Borrower
or any Subsidiary of the Borrower, and any amounts retained by Sprint PCS,
under Section 10 of any Sprint Management Agreement.

         "Sprint Services Agreement (Alamosa Texas)" means that certain Sprint
PCS Services Agreement dated as of December 23, 1999 executed by Sprint
Spectrum and the Original Borrower, as assigned and transferred to, and assumed
by, Alamosa Texas pursuant to that certain Notice, Consent, Transfer and
Assignment dated as of February 3, 2000, but effective as of February 8, 2000,
and any documents incorporated by reference in said agreement (pursuant to
which, among other things, Alamosa Texas may delegate the performance of
certain services to Sprint PCS for fees that represent an adjustment of the
fees paid by Sprint PCS to Alamosa Texas under Section 10 of the Sprint
Management Agreement (Alamosa Texas).

         "Sprint Services Agreement (Alamosa Wisconsin)" means that certain
Sprint PCS Services Agreement dated as of December 6, 1999 executed by Sprint
Spectrum and Alamosa Wisconsin and any documents incorporated by reference in
said agreement (pursuant to which, among other things, Alamosa Wisconsin may
delegate the performance of certain services to Sprint PCS for fees that
represent an adjustment of the fees paid by Sprint PCS to Alamosa Wisconsin
under Section 10 of the Sprint Management Agreement (Alamosa Wisconsin).

         "Sprint Services Agreements" means the Sprint Services Agreement
(Alamosa Texas) and the Sprint Services Agreement (Alamosa Wisconsin).

         "Sprint Spectrum" means Sprint Spectrum L.P., a Delaware limited
partnership.

         "Sprint Spectrum Trademark and Service Mark License Agreement (Alamosa
Texas)" means that certain Sprint Spectrum Trademark and Service Mark License
Agreement dated as of December 23, 1999 executed by Sprint Spectrum and the
Original Borrower, as assigned and transferred to, and assumed by, Alamosa
Texas pursuant to that certain Notice, Consent, Transfer and Assignment dated
as of February 3, 2000, but effective as of February 8, 2000, and any documents
incorporated by reference in said agreement.

         "Sprint Spectrum Trademark and Service Mark License Agreement (Alamosa
Wisconsin)" means that certain Sprint Spectrum Trademark and Service Mark
License Agreement dated as of

CREDIT AGREEMENT - Page 26

<PAGE>   34

December 6, 1999 executed by Sprint Spectrum and Alamosa Wisconsin and any
documents incorporated by reference in said agreement.

         "Sprint Spectrum Trademark and Service Mark License Agreements" means
the Sprint Spectrum Trademark and Service Mark License Agreement (Alamosa
Texas) and the Sprint Spectrum Trademark and Service Mark License Agreement
(Alamosa Wisconsin).

         "Sprint Trademark and Service Mark License Agreement (Alamosa Texas)"
means that certain Sprint Trademark and Service Mark License Agreement dated as
of December 23, 1999 executed by Sprint Communications Company, L.P. and the
Original Borrower, as assigned and transferred to, and assumed by, Alamosa
Texas pursuant to that certain Notice, Consent, Transfer and Assignment dated
as of February 3, 2000, but effective as of February 8, 2000, and any documents
incorporated by reference in said agreement.

         "Sprint Trademark and Service Mark License Agreement (Alamosa
Wisconsin)" means that certain Sprint Trademark and Service Mark License
Agreement dated as of December 6, 1999 executed by Sprint Communications
Company, L.P. and Alamosa Wisconsin and any documents incorporated by reference
in said agreement.

         "Sprint Trademark and Service Mark License Agreements" means the
Sprint Trademark and Service Mark License Agreement (Alamosa Texas) and the
Sprint Trademark and Service Mark License Agreement (Alamosa Wisconsin).

         "Subordinated Guarantee" means a Guarantee executed by the Borrower or
any Subsidiary of the Borrower by virtue of its execution of the Holdings
Senior Notes Indenture solely for the purpose of being obligated under the
guaranty provisions contained in Article X and Article XI thereof pursuant to
which it, on a subordinated basis, guarantees payment of the Holdings Senior
Notes on terms satisfactory to the Administrative Agent and the Required
Lenders, which terms shall generally include, without limitation, the
following: (a) an agreement that (i) each of the Trustee and the Noteholders
will not, directly or indirectly, make any demand for payment or other amount
or exercise any other right or remedy under such guaranty, and will not take,
accept, receive or retain any such payment or other amount or the benefit of
any such other right or remedy, and (ii) such guarantor will not, directly or
indirectly, make or pay any payment or other amount or provide any other
benefit to or for the benefit of the Trustee or any holder of the Holding
Senior Notes, in each case unless and until each of the following two
conditions has been satisfied: (A) a Holdings Senior Notes Event of Default
shall have occurred and be continuing and the Administrative Agent (with a copy
to its counsel) shall have received at least ten Business Days' prior written
notice of such Holdings Senior Notes Event of Default, and (B) none of (1) an
Event of Default under clause (a) of Section 11.1 shall have occurred (unless
such Event of Default shall have been cured or waived or all Obligations have
been paid in full in cash and all Commitments have terminated or expired), (2)
the maturity of any of the Loans or other Obligations shall have been
accelerated (unless such acceleration has been rescinded), (C) an Event of
Default under clause (e) or clause (f) of Section 11.1 shall have occurred or
(D) a 179 day blockage period shall be in effect (which blockage period may be
commenced by the giving of a blockage notice by the Administrative Agent to the
Trustee after the occurrence of any Event of Default); (b) an agreement of each
of the Trustee and the

CREDIT AGREEMENT - Page 27

<PAGE>   35

Noteholders that, in the event it receives, directly or indirectly, any payment
or other amount from such guarantor that it is not permitted to receive, it
will promptly, upon becoming aware thereof or upon written demand therefor made
by the Administrative Agent or any Lender, deliver such payment or other
amount, in the form received, to the Administrative Agent for and on behalf of
the Lenders; and (c) an agreement that the terms and provisions of such
guaranty relating to the subordination thereof shall inure to the benefit of,
and be enforceable by, the Administrative Agent for and on behalf of the
Lenders and may not be amended without the prior written consent of the
Administrative Agent and the Required Lenders (provided, however, that the
Trustee shall be permitted to rely upon a representation from the
Administrative Agent as to any consent of the Required Lenders).

         "Subsidiary" means, with respect to any Person, any corporation or
other entity of which at least a majority of the outstanding shares of stock or
other ownership interests having by the terms thereof ordinary voting power to
elect a majority of the board of directors (or Persons performing similar
functions) of such corporation or entity (irrespective of whether or not at the
time, in the case of a corporation, stock of any other class or classes of such
corporation shall have or might have voting power by reason of the happening of
any contingency) is at the time directly or indirectly owned or controlled by
such Person or one or more of its Subsidiaries or by such Person and one or
more of its Subsidiaries.

         "Supply Agreement" means the that certain CDMA 1900 Sprintcom
Additional Affiliate Agreement dated as of December 21, 1998, by and between
the Borrower and Nortel Networks, as amended by that certain Amendment No. 1 to
DMS-MTX Cellular Supply Agreement dated as of January 12, 1999, Amendment No. 2
DMS-MTX Cellular Supply Agreement dated as of March 1, 1999, as reaffirmed as
of June 10, 1999, Amendment No. 3 DMS-MTX Cellular Supply Agreement dated as of
August 11, 1999, and Amendment No. 4 dated as of February 8, 2000, and as
further amended, supplemented or restated from time to time.

         "Total Capitalization" means, as of any date of determination and with
respect to any Person and its Consolidated Subsidiaries, the sum of (a) Total
Debt of such Person and its Consolidated Subsidiaries as of such date plus (b)
Contributed Capital of such Person as of such date.

         "Total Debt" means, as of any date of determination and with respect
to any Person and its Consolidated Subsidiaries, the aggregate principal amount
of all Debt outstanding, determined on a consolidated basis in accordance with
GAAP.

         "Tranche A Commitment" means, as to any Tranche A Lender, the
obligation of such Tranche A Lender to make or continue Tranche A Loans
hereunder in an aggregate principal amount up to but not exceeding the amount
set forth opposite the name of such Tranche A Lender on the signature pages
hereto under the heading "Tranche A Commitment" or, if such Tranche A Lender is
a party to an Assignment and Acceptance, the amount of the "Tranche A
Commitment" set forth in the most recent Assignment and Acceptance of such
Tranche A Lender, as the same may be reduced or terminated pursuant to Section
2.13 or 11.2, and "Tranche A Commitments" means such obligations of all Tranche
A Lenders. As of the Closing Date, the aggregate principal amount of the
Tranche A Commitments is $167,000,000.

CREDIT AGREEMENT - Page 28

<PAGE>   36

         "Tranche A Commitment Termination Date" means the earlier to occur of
(a) August 8, 2002, (b) the date on which the Tranche A Loans are fully funded,
or (c) February 8, 2001, if less than $100,000,000 in aggregate principal
amount of the Loans has been advanced as of such date (regardless of the
outstanding principal amount of the Loans as of such date).

         "Tranche A Lenders" means the Lenders who hold Tranche A Loans or who
have Tranche A Commitments.

         "Tranche A Loans" means as specified in Section 2.1(a).

         "Tranche A Notes" means the promissory notes evidencing the Tranche A
Loans executed in accordance with Section 2.2.

         "Tranche B Commitment" means, as to any Tranche B Lender, the
obligation of such Tranche B Lender to make or continue Tranche B Loans
hereunder in an aggregate principal amount up to but not exceeding the amount
set forth opposite the name of such Tranche B Lender on the signature pages
hereto under the heading "Tranche B Commitment" or, if such Tranche B Lender is
a party to an Assignment and Acceptance, the amount of the "Tranche B
Commitment" set forth in the most recent Assignment and Acceptance of such
Tranche B Lender, as the same may be reduced or terminated pursuant to Section
2.13 or 11.2, and "Tranche B Commitments" means such obligations of all Tranche
B Lenders. As of the Closing Date, the aggregate principal amount of the
Tranche B Commitments is $58,000,000.

         "Tranche B Commitment Termination Date" means the earlier to occur of
(a) August 8, 2002, (b) the date on which the Tranche B Loans are fully funded,
or (c) February 8, 2001, if less than $100,000,000 in aggregate principal
amount of the Loans has been advanced as of such date (regardless of the
outstanding principal amount of the Loans as of such date).

         "Tranche B Lenders" means the Lenders who hold Tranche B Loans or who
have Tranche B Commitments.

         "Tranche B Loans" means as specified in Section 2.1(b).

         "Tranche B Notes" means the promissory notes evidencing the Tranche B
Loans executed in accordance with Section 2.2.

         "Tranche C Commitment" means, as to any Tranche C Lender, the
obligation of such Tranche C Lender to make or continue Tranche C Loans
hereunder in an aggregate principal amount up to but not exceeding the amount
set forth opposite the name of such Tranche C Lender on the signature pages
hereto under the heading "Tranche C Commitment" or, if such Tranche C Lender is
a party to an Assignment and Acceptance, the amount of the "Tranche C
Commitment" set forth in the most recent Assignment and Acceptance of such
Tranche C Lender, as the same may be reduced or terminated pursuant to Section
2.13 or 11.2, and "Tranche C Commitments" means such obligations of all Tranche
C Lenders. As of the Closing Date, the aggregate principal amount of the
Tranche C Commitments is $25,000,000.

CREDIT AGREEMENT - Page 29

<PAGE>   37

         "Tranche C Commitment Termination Date" means the earlier to occur of
(a) February 8, 2002, (b) the date on which the Tranche C Loans are fully
funded, or (c) February 8, 2001, if less than $100,000,000 in aggregate
principal amount of the Loans has been advanced as of such date (regardless of
the outstanding principal amount of the Loans as of such date).

         "Tranche C Lenders" means the Lenders who hold Tranche C Loans or who
have Tranche C Commitments.

         "Tranche C Loans" means as specified in Section 2.1(c).

         "Tranche C Notes" means the promissory notes evidencing the Tranche C
Loans executed in accordance with Section 2.2.

         "Trustee" means Norwest Bank Minnesota, N.A. in its capacity as
trustee under the Holdings Senior Notes Indenture and any successor trustee
thereunder.

         "Type" means any type of Loan (i.e., a Base Rate Loan or Eurodollar
Loan).

         "UCC" means the Uniform Commercial Code as in effect in the State of
New York and/or any other jurisdiction, the laws of which may be applicable to
or in connection with the creation, perfection or priority of any Lien on any
Property created pursuant to any Security Document.

         "Unrestricted Subsidiary" means a Subsidiary of Holdings, other than
the Borrower or a Subsidiary of the Borrower, designated by Holdings as an
"Unrestricted Subsidiary" (which may not be the Borrower or any of its
Subsidiaries) which is a corporation, trust, limited liability company,
partnership or any other type of entity reasonably acceptable to the Required
Lenders, and which (a) complies with the provisions of the laws of the state of
its formation relating to corporations, limited liability companies,
partnerships or such other entities, as applicable, (b) observes all customary
formalities regarding its existence, including having meetings of its board of
directors or analogous governing body separate from those held by the Loan
Parties, (c) accurately maintains its financial statements, accounting records
and other documents separate from those of its shareholders, members, partners,
Affiliates of its shareholders, members or partners and any other Person, (d)
does not commingle its assets with those of its shareholders, members,
partners, Affiliates of its shareholders, members or partners and any other
Person, (e) accurately maintains its own bank accounts and separate books of
account, (f) pays its own liabilities from its own separate assets, (g)
identifies itself, in all dealings with the public, under its own name or trade
names and as a separate and distinct entity and not as being a division or a
part of any other entity, (h) does not identify its shareholders, members or
partners as being a division or part of the Borrower or Holdings, provided that
each Unrestricted Subsidiary may describe its status vis-a-vis its parent or
ultimate parent entity, (i) is adequately capitalized in light of the nature of
its business, (j) does not assume or guarantee the liabilities of its
shareholders, members or partners, (k) does not acquire obligations or
securities of its shareholders, members or partners (or any predecessor
corporation, partnership or limited liability company), or any Affiliates of
its shareholders, members or partners, (l) does not make loans to its
shareholders, members or partners (or any predecessor), or any Affiliates of
its shareholders, members or partners, and (m) does not enter into or become a
party to

CREDIT AGREEMENT - Page 30

<PAGE>   38

any transaction with its shareholders, members or partners (or any predecessor)
or any Affiliates of its shareholders, members or partners, except on terms
which are no less favorable to such Unrestricted Subsidiary than would be
obtained in a comparable arm's length transaction with an unrelated third
party.

         "U.S." means the United States of America.

         "U.S. Person" means a citizen or resident of the U.S., a corporation,
partnership or other entity created or organized in or under any laws of the
U.S. or any estate or trust that is subject to U.S. Federal income taxation
regardless of the source of its income.

         "U.S. Taxes" means any present or future tax, assessment or other
charge or levy imposed by or on behalf of the U.S. or any taxing authority
thereof.

         "Vendor" means Nortel Networks in its capacity as vendor under the
Supply Agreement.

         "Voting Stock" of any Person means Capital Stock of such Person which
ordinarily has voting power for the election of directors, managers or general
partners (or persons performing similar functions) of such Person, whether at
all times or only for so long as no senior class of securities has such voting
power by reason of any contingency.

         "Wholly-Owned Subsidiary" means, with respect to any Person, a
Subsidiary of such Person all of whose outstanding Capital Stock (other than
directors' qualifying shares, if any) shall at the time be owned by such Person
and/or one or more of its Wholly-Owned Subsidiaries.

         "Wireless Subscribers" means, at any time, all customers then
receiving wireless communications services from the Borrower or any Subsidiary
of the Borrower through the Service Area Network in the Service Area.

         "Year 2000 Compliant" means that (a) the services, products or other
item(s) at issue accurately process, provide and/or receive all date/time data
(including calculating, comparing, sequencing, processing and outputting)
within, from, into and between centuries (including the twentieth and
twenty-first centuries and the years 1999 and 2000), including leap year
calculations, and (b) neither the performance nor the functionality nor the
business' provision of the services, products and other item(s) at issue will
be affected by any dates/times prior to, on, after or spanning January 1, 2000.
The design of the services, products and other item(s) at issue to ensure
compliance with the "year 2000" representations and warranties and covenants
contained in this Agreement includes proper date/time data century recognition
and recognition of 1999 and 2000, calculations that accommodate single century
and multi-century formulae and date/time values before, on, after and spanning
January 1, 2000, and date/time data interface values that reflect the century,
1999 and 2000. In particular, but without limitation, such design means that
(i) no value for current date/time will cause any error, interruption or
decreased performance in or for such services, products and other item(s), (ii)
all manipulations of date and time related data (including calculating,
comparing, sequencing processing and outputting) will produce correct results
for all valid dates and times when used independently or in combination with
other services, products and/or items, (iii) date/time

CREDIT AGREEMENT - Page 31

<PAGE>   39

elements in interfaces and data storage will specify the century to eliminate
date ambiguity without human intervention, including leap year calculations,
(iv) where any date/time element is represented without a century, the correct
century will be unambiguous for all manipulations involving that element, (v)
authorization codes, passwords and zaps (purge functions) will function
normally and in the same manner during, prior to, on and after January 1, 2000,
including the manner in which they function with respect to expiration dates
and CPU serial numbers, and (vi) the business' supply of the services, products
and other item(s) will not be interrupted, delayed, decreased or otherwise
affected by the advent of the year 2000.

         Section 1.2 Other Definitional Provisions. All definitions contained
in this Agreement are equally applicable to the singular and plural forms of
the terms defined. The words "hereof", "herein" and "hereunder" and words of
similar import referring to this Agreement refer to this Agreement as a whole
and not to any particular provision of this Agreement. The term "continuing",
"continuation" or "continuance" means, in reference to any Default or Event of
Default that has occurred, that such Default or Event of Default has not been
either cured to the reasonable satisfaction of the Administrative Agent within
the applicable grace period (if any) specified in this Agreement or the other
Loan Documents (as applicable) or waived in writing by the requisite Lenders in
accordance with Section 13.11. The term "pro rata" as it relates to the
application of payments to the Tranche A Loans, the Tranche B Loans and/or the
Tranche C Loans means pro rata based upon the relative outstanding principal
amount of such Loans. Unless otherwise specified, all Article and Section
references pertain to this Agreement. Terms used herein that are defined in the
UCC, unless otherwise defined herein, shall have the meanings specified in the
UCC. All references in this Agreement to any agreement shall be deemed to mean
and refer to such agreement as it may be amended, modified or supplemented from
time to time if (but only if) such amendment, modification or supplement has
been approved by the Administrative Agent and the Required Lenders, is
expressly referred to in such reference or is otherwise expressly permitted by
the terms of this Agreement.

         Section 1.3 Accounting Terms and Determinations.

         (a) All accounting terms not specifically defined herein shall be
construed in accordance with GAAP (subject to year end adjustments, if
applicable) consistent with such accounting principles applied in the
preparation of the audited financial statements referred to in Section 7.2(a).
All financial information delivered to the Administrative Agent pursuant to
Section 8.1 shall be prepared in accordance with GAAP (subject to year end
adjustments, if applicable) applied on a basis consistent with such accounting
principles applied in the preparation of the audited financial statements of
such Person referred to in Section 7.2 or in accordance with Section 8.7.

         (b) The Borrower shall deliver to the Administrative Agent and the
Lenders, at the same time as the delivery of any annual or quarterly financial
statement under Section 8.1, (i) a description, in reasonable detail, of any
material variation between the application of GAAP employed in the preparation
of the immediately preceding annual or quarterly financial statements as to
which no objection has been made in accordance with the last sentence of
Section 1.3(a) preceding and (ii) reasonable estimates of the difference
between such statements arising as a consequence thereof.

CREDIT AGREEMENT - Page 32

<PAGE>   40

         (c) To enable the ready and consistent determination of compliance
with the covenants set forth in this Agreement, neither the Borrower nor
Holdings will change the last day of its fiscal year from December 31 or the
last days of its first three fiscal quarters in each of its fiscal years from
March 31, June 30 and September 30, respectively.

         (d) Unless otherwise expressly provided herein to the contrary, all
references herein to the Closing Date shall be deemed to mean and refer to the
Closing Date after giving effect to all transactions which occur on or before
such date.

         Section 1.4 Financial Covenants and Reporting. All financial
statements and reports required to be delivered pursuant to this Agreement and
the other Loan Documents, and all financial covenants (if any) contained in
this Agreement, shall be prepared or determined (as applicable) in accordance
with GAAP (except as may be expressly provided to the contrary herein) and, if
and to the extent that such statements, reports or covenants are to be prepared
or determined on a consolidated basis, shall be prepared or determined on a
consolidated basis for Holdings and its Consolidated Subsidiaries or the
Borrower and its Consolidated Subsidiaries (as applicable), except as may be
expressly provided to the contrary herein.

                                   ARTICLE 2

                                     Loans

         Section 2.1 Commitments.

         (a) Tranche A Loans. Subject to the terms and conditions of this
Agreement (including, without limitation, Section 2.13(a)), each Tranche A
Lender severally agrees to make one or more loans to the Borrower from time to
time from and including the Closing Date to but excluding the Tranche A
Commitment Termination Date up to but not exceeding the amount of such Tranche
A Lender's Tranche A Commitment as then in effect. Notwithstanding anything to
the contrary contained in this Agreement, the Borrower, the Administrative
Agent and the Lenders agree that, as of the Closing Date, the aggregate
outstanding principal amount of the Original Tranche A Loans is $3,114,890.03,
which amount shall be deemed outstanding as Tranche A Loans hereunder. (Such
loans referred to in this Section 2.1(a) now or hereafter made or deemed made
by the Tranche A Lenders to the Borrower, including, without limitation, such
loans which remain outstanding after the Tranche A Commitment Termination Date,
are hereinafter collectively called the "Tranche A Loans".) The Borrower may
not reborrow the Tranche A Loans which have been repaid; provided, however,
that the Borrower may reborrow the Tranche A Loans which have been prepaid in
accordance with Section 2.7(e) in the event that the Borrower elects to
increase the Tranche A Commitments in accordance with Section 2.13(c) by an
amount equal to or greater than the amount of such reborrowed Loan.

         (b) Tranche B Loans. Subject to the terms and conditions of this
Agreement (including, without limitation, Section 2.13(a)), each Tranche B
Lender severally agrees to make one or more loans to the Borrower from time to
time from and including the Closing Date to but excluding the Tranche B
Commitment Termination Date up to but not exceeding the amount of such Tranche
B

CREDIT AGREEMENT - Page 33

<PAGE>   41

Lender's Tranche B Commitment as then in effect; provided, however, that the
aggregate outstanding principal amount of the Tranche B Loans shall not at any
time exceed the Permitted Third-Party Expenses Borrowing Base. Notwithstanding
anything to the contrary contained in this Agreement, the Borrower, the
Administrative Agent and the Lenders agree that, as of the Closing Date, the
aggregate outstanding principal amount of the Original Tranche B Loans is
$1,040,430.75, which amount shall be deemed outstanding as Tranche B Loans
hereunder. (Such loans referred to in this Section 2.1(b) now or hereafter made
or deemed made by the Tranche B Lenders to the Borrower, including, without
limitation, such loans which remain outstanding after the Tranche B Commitment
Termination Date, are hereinafter collectively called the "Tranche B Loans".)
The Borrower may not reborrow the Tranche B Loans which have been repaid;
provided, however, that the Borrower may reborrow the Tranche B Loans which
have been prepaid in accordance with Section 2.7(e) in the event that the
Borrower elects to increase the Tranche B Commitments in accordance with
Section 2.13(c) by an amount equal to or greater than the amount of such
reborrowed Loan.

         (c) Tranche C Loans. Subject to the terms and conditions of this
Agreement (including, without limitation, Section 2.13(a)), each Tranche C
Lender severally agrees to make one or more loans to the Borrower from time to
time from and including the Closing Date to but excluding the Tranche C
Commitment Termination Date up to but not exceeding the amount of such Tranche
C Lender's Tranche C Commitment as then in effect. Notwithstanding anything to
the contrary contained in this Agreement, the Borrower, the Administrative
Agent and the Lenders agree that, as of the Closing Date, the aggregate
outstanding principal amount of the Original Tranche C Loans is $368,519.86,
which amount shall be deemed outstanding as Tranche C Loans hereunder. (Such
loans referred to in this Section 2.1(c) now or hereafter made or deemed made
by the Tranche C Lenders to the Borrower, including, without limitation, such
loans which remain outstanding after the Tranche C Commitment Termination Date,
are hereinafter collectively called the "Tranche C Loans".) The Borrower may
not reborrow the Tranche C Loans which have been repaid; provided, however,
that the Borrower may reborrow the Tranche C Loans which have been prepaid in
accordance with Section 2.7(e) in the event that the Borrower elects to
increase the Tranche C Commitments in accordance with Section 2.13(c) by an
amount equal to or greater than the amount of such reborrowed Loan.

         (d) Continuation and Conversion of Loans. Subject to the terms and
conditions of this Agreement, the Borrower may borrow the Loans as Base Rate
Loans or Eurodollar Loans and, until the applicable Maturity Date, the Borrower
may Continue Eurodollar Loans or Convert Loans of one Type into Loans of the
other Type.

         (e) Lending Offices. Loans of each Type made by each Lender shall be
made and maintained at such Lender's Applicable Lending Office for Loans of
such Type.

         (f) Determinations of the Permitted Third-Party Expenses Borrowing
Base. The Permitted Third-Party Expenses Borrowing Base shall be determined in
good faith by the Administrative Agent as of the Closing Date and will be
redetermined in good faith by the Administrative Agent thereafter promptly
after the delivery, or required delivery, of a Permitted Third-Party Expenses
Borrowing Base Report in accordance with Section 8.1(k), in each case as of the
applicable date (i.e., as of the date of the Notice of Borrowing, if
applicable, or as of the last day

CREDIT AGREEMENT - Page 34

<PAGE>   42

of the immediately preceding fiscal quarter). In addition, the Permitted
Third-Party Expenses Borrowing Base shall be determined in good faith by the
Administrative Agent prior to and in connection with each new Tranche B Loan or
Tranche C Loan, as the case may be, and may be redetermined in good faith by
the Administrative Agent at any time and from time to time upon the occurrence
and during the continuation of a Default.

         Section 2.2 Notes.

         (a) Notes. All of the Tranche A Loans, Tranche B Loans and Tranche C
Loans made by each Lender shall be evidenced by a single promissory note of the
Borrower in substantially the form of Exhibit B-1, Exhibit B-2 and Exhibit B-3,
respectively, hereto dated the Closing Date (or such later date on which such
Lender becomes a party to this Agreement), payable to the order of such Lender
in a principal amount equal to the sum of (i) the aggregate principal amount of
such Loans of such Lender plus (ii) the aggregate principal amount of the
unfunded Commitment of such Lender relating to such Loans as originally in
effect. Each Lender is hereby authorized by the Borrower to endorse on the
schedule (or a continuation thereof) attached to the Notes of such Lender, to
the extent applicable, the date, amount and Type of and the Interest Period for
each applicable Loan made by such Lender to the Borrower and the amount of each
payment or prepayment of principal of such Loan received by such Lender,
provided that any failure by such Lender to make any such endorsement shall not
affect the obligations of the Borrower under any such Note or this Agreement in
respect of any such Loan.

         (b) Registered Notes. Any Lender that is not a U.S. Person and that
could become completely exempt from withholding of U.S. Taxes in respect of
payment of any Obligations due to such Lender hereunder relating to any of its
Loans if such Loans were in registered form for U.S. Federal income tax
purposes may request the Borrower (through the Administrative Agent), and the
Borrower agrees thereupon, to exchange such Lender's Note evidencing its Loans
for a promissory note registered as provided in Section 13.8(h) hereof (a
"Registered Note"). Registered Notes may not be exchanged for Notes that are
not in registered form.

         Section 2.3 Repayment of Loans. The Borrower shall pay to the
Administrative Agent for the account of each Lender the principal of the
Tranche A Loans, the Tranche B Loans and the Tranche C Loans outstanding as of
the Tranche A Commitment Termination Date, the Tranche B Commitment Termination
Date and the Tranche C Commitment Termination Date, respectively (and the
principal of each of such Loans outstanding as of such dates shall be due and
payable) in 20 quarterly installments, commencing on the first Quarterly Date
after the Amortization Commencement Date and continuing on each Quarterly Date
thereafter through and including the Maturity Date, each of which installments
shall be in an amount equal to the percentage of the aggregate principal amount
of such Loans outstanding as of such applicable date specified opposite such
installment in the following table:

CREDIT AGREEMENT - Page 35

<PAGE>   43

<TABLE>
<CAPTION>
-------------------------------------------------------------------------------
  <S>                          <C>
                               Percentage of the Aggregate Principal Amount of
   Principal Installment              each of the Loans Due and Payable
-------------------------------------------------------------------------------
          1                                         3.75%
-------------------------------------------------------------------------------
          2                                         3.75%
-------------------------------------------------------------------------------
          3                                         5.14%
-------------------------------------------------------------------------------
          4                                         5.14%
-------------------------------------------------------------------------------
          5                                         5.14%
-------------------------------------------------------------------------------
          6                                         5.14%
-------------------------------------------------------------------------------
          7                                         5.14%
-------------------------------------------------------------------------------
          8                                         5.14%
-------------------------------------------------------------------------------
          9                                         5.14%
-------------------------------------------------------------------------------
         10                                         5.14%
-------------------------------------------------------------------------------
         11                                         5.14%
-------------------------------------------------------------------------------
         12                                         5.14%
-------------------------------------------------------------------------------
         13                                         5.14%
-------------------------------------------------------------------------------
         14                                         5.14%
-------------------------------------------------------------------------------
         15                                         5.14%
-------------------------------------------------------------------------------
         16                                         5.14%
-------------------------------------------------------------------------------
         17                                         5.14%
-------------------------------------------------------------------------------
         18                                         5.14%
-------------------------------------------------------------------------------
         19                                         5.14%
-------------------------------------------------------------------------------
         20                                         5.12%
-------------------------------------------------------------------------------
</TABLE>

In addition and notwithstanding anything to the contrary contained in this
Section 2.3 preceding, the Borrower shall pay to the Administrative Agent for
the account of each Lender all outstanding principal of the Loans (and all
outstanding principal of the Loans shall be due and payable) on the Maturity
Date.

         Section 2.4 Interest.

         (a) Interest Rate. The Borrower shall pay to the Administrative Agent
for the account of each Lender interest on the unpaid principal amount of each
Loan made by such Lender (or deemed made by such Lender with respect to a Loan
assigned to such Lender after the making of such Loan) to the Borrower for the
period commencing on the date of such Loan to, but excluding, the date such
Loan shall be paid in full, at the following rates per annum:

                  (i) during the periods such Loan is a Base Rate Loan, the
         lesser of (A) the Base Rate plus the Applicable Margin or (B) the
         Maximum Rate; and

                  (ii) during the periods such Loan is a Eurodollar Loan, the
         lesser of (A) the Adjusted Eurodollar Rate plus the Applicable Margin
         or (B) the Maximum Rate.

CREDIT AGREEMENT - Page 36

<PAGE>   44

         (b) Payment Dates. Accrued interest on the Loans shall be due and
payable as follows:

                  (i) in the case of Base Rate Loans, on each Monthly Date;

                  (ii) in the case of each Eurodollar Loan, on the last day of
         the Interest Period with respect thereto and, in the case of an
         Interest Period greater than three months, at three- month intervals
         after the first day of such Interest Period;

                  (iii) upon the payment or prepayment (whether mandatory or
         optional) of any Loan or the Conversion of any Loan to a Loan of the
         other Type (but only on the principal amount so paid, prepaid or
         Converted); and

                  (iv)  with respect to all Loans, on the Maturity Date.

         (c) Default Interest. Notwithstanding the foregoing, the Borrower
shall pay to the Administrative Agent for the account of each Lender interest
at the applicable Default Rate (i) at all times during which any Default has
occurred and is continuing, on any principal of any Loan outstanding, and (ii)
to the fullest extent permitted by law, any other amount payable by the
Borrower under this Agreement or any other Loan Document to or for the account
of such Lender which is not paid in full when due (whether at stated maturity,
by acceleration or otherwise) for the period from and including the due date
thereof to but excluding the date the same is paid in full. Interest payable at
the Default Rate shall be payable from time to time on demand by the
Administrative Agent.

         Section 2.5 Borrowing Procedure. The Borrower shall give the
Administrative Agent notice of each borrowing hereunder in accordance with
Section 2.9. Not later than 1:00 p.m. (New York, New York time) on the date
specified for each borrowing hereunder, each Lender will make available the
amount of the Loan to be made by it on such date to the Administrative Agent,
at the Principal Office, in immediately available funds, for the account of the
Borrower. The amount of each borrowing hereunder so received by the
Administrative Agent shall, subject to the terms and conditions of this
Agreement, be made available, for and on behalf of the Borrower, in immediately
available funds by no later than 1:00 p.m. (New York, New York time); provided,
however, that the Administrative Agent may, in its discretion, cause such
amount to be made available directly to or for the benefit of the Person who is
to receive the proceeds of such Loan in accordance with Section 2.10.
Notwithstanding anything to the contrary contained in this Agreement, if and to
the extent that Nortel Networks is a Lender under this Agreement, the Borrower
further hereby irrevocably agrees that each Loan to be advanced by Nortel
Networks to the Borrower in accordance with this Agreement (and only in
accordance with this Agreement and after the Administrative Agent's receipt of
a Notice of Borrowing executed by the Borrower) may (in the discretion of
Nortel Networks and if and to the extent that the proceeds of such Loan are to
be paid to Nortel Networks) be effectively disbursed on the date set forth in
the Notice of Borrowing for such disbursement to the Borrower by virtue of a
credit in the amount of such Loan given to the Borrower under the Supply
Agreement.

CREDIT AGREEMENT - Page 37

<PAGE>   45

         Section 2.6 Optional Prepayments, Conversions and Continuations of
Loans. Subject to Section 2.8, the Borrower shall have the right from time to
time to prepay the Loans in whole or in part, to Convert all or part of a Loan
of one Type into a Loan of another Type or to Continue Eurodollar Loans;
provided that: (a) the Borrower shall give the Administrative Agent notice of
each such prepayment, Conversion or Continuation as provided in Section 2.9,
(b) Eurodollar Loans may only be Converted on the last day of the Interest
Period and any prepayment of Eurodollar Loans on any day other than the last
day of the Interest Period shall be subject to payment of the additional
compensation specified in Section 4.5, (c) except for Conversions of Eurodollar
Loans into Base Rate Loans, no Conversions or Continuations shall be made while
a Default has occurred and is continuing, and (d) optional prepayments of the
Loans shall be applied pro rata to the principal of the Loans prepaid in the
inverse order of the maturities of the then remaining installments of such
Loans. No amounts prepaid pursuant to this Section 2.6 may be reborrowed.

         Section 2.7 Mandatory Prepayments.

         (a) Asset Dispositions, etc. The Borrower will, within two Business
Days after any Loan Party receives any Net Proceeds of any Asset Disposition,
proceeds of any Insurance Recovery or proceeds of condemnation awards
aggregating in excess of $250,000 during any period of 12 consecutive months or
less (the amount of such proceeds exceeding $250,000 received during any such
period are herein called the "Excess Proceeds Amount"), pay to the
Administrative Agent, as a prepayment of the Loans, an aggregate amount equal
to the Excess Proceeds Amount; provided, however, that no such prepayment will
be required if and to the extent that the Excess Proceeds Amount is fully
re-invested in productive assets used in the ordinary course of such Loan
Party's business within 60 days of the receipt of such Excess Proceeds Amount
or, if and to the extent that such Excess Proceeds Amount has been, prior to
the expiration of such 60 day period, deposited into a cash collateral account
held by the Administrative Agent pursuant to an agreement in form and substance
satisfactory to the Administrative Agent, within 120 days of the receipt of
such Excess Proceeds Amount; provided, further, however, that the Excess
Proceeds Amount (or portion thereof) not so re-invested within 60 days of the
receipt thereof shall be deposited into a cash collateral account held by the
Administrative Agent pursuant to an agreement in form and substance
satisfactory to the Administrative Agent until such time as such amount is
either re-invested within 120 days of the receipt thereof or applied to the
Loans or other Obligations as provided in this Section 2.7.

         (b) Excess Cash Flow. The Borrower will, commencing on the first March
31st following the Tranche A Commitment Termination Date and on each March 31st
thereafter, pay (or cause to be paid) to the Administrative Agent, as a
prepayment of the Loans and other Obligations then outstanding, an aggregate
amount equal to 50% of Excess Cash Flow for the fiscal year then most recently
ended.

         (c) Borrowing Base. If at any time on or prior to the date that is six
months after the Tranche B Commitment Termination Date, the aggregate
outstanding principal amount of the Tranche B Loans and Tranche C Loans, the
proceeds of which have been used to pay Permitted Third-Party Expenses, exceeds
an amount equal to the lesser of (A) the Permitted Third-Party Expenses
Borrowing Base then in effect (as determined from time to time in accordance
with

CREDIT AGREEMENT - Page 38

<PAGE>   46

Section 2.1(f)) or (B) the aggregate amount of the Tranche B Commitments and
the Tranche C Commitments as of the Tranche B Commitment Termination Date,
then, within one Business Day thereafter, the Borrower shall pay to the
Administrative Agent the amount of such excess as a prepayment of the Tranche B
Loans and/or the Tranche C Loans.

         (d) Sale of the Service Area Network. The Borrower shall, concurrently
with any sale, transfer or other disposition of the Service Area Network or any
material portion thereof, prepay in full (i) all outstanding principal amount
of the Loans, (ii) all interest accrued and unpaid with respect to all Loans,
and (iii) all other outstanding Obligations.

         (e) Holdings Senior Notes Issuance. The Borrower shall, substantially
concurrently with the date upon which Holdings receives any proceeds of any
issuance of Holdings Senior Notes, pay to the Administrative Agent, as a
prepayment of the Loans, an aggregate amount equal to the lesser of (i)
$75,000,000 or (ii) the aggregate principal amount of the Loans then
outstanding.

         (f) Application of Mandatory Prepayments. All prepayments pursuant to
Section 2.7(a) and Section 2.7(b) shall be applied pro rata to the outstanding
principal of the Tranche A Loans, the Tranche B Loans and the Tranche C Loans
(based upon the outstanding principal amounts of such Loans) in the inverse
order of the maturities of the then remaining installments of such Loans and
then to the remaining outstanding Obligations in such order as the
Administrative Agent may determine. All prepayments pursuant to Section 2.7(c)
shall be applied pro rata to the outstanding principal of the Tranche B Loans
and the Tranche C Loans (based upon the outstanding principal amounts of such
Loans) in the inverse order of the maturities of the then remaining
installments of such Loans and then to the remaining outstanding Obligations in
such order as the Administrative Agent may determine. All prepayments pursuant
to Section 2.7(e) shall be applied pro rata to the outstanding principal of the
Tranche A Loans, the Tranche B Loans and the Tranche C Loans (based upon the
outstanding principal amounts of such Loans) and shall be applied pro rata to
the then remaining installments of such Loans.

         (h) No Reborrowing. No amounts of the Loans prepaid pursuant to this
Section 2.7 may be reborrowed.

         Section 2.8 Minimum Amounts. Except for Conversions and prepayments
pursuant to Section 2.7 and Article 4, each borrowing, each Conversion and each
optional prepayment of principal of the Loans shall be in an amount at least
equal to $3,000,000 or an integral multiple of $100,000 in excess thereof
(borrowings, prepayments or Conversions of or into Loans of different Types or,
in the case of Eurodollar Loans, having different Interest Periods at the same
time hereunder shall be deemed separate borrowings, prepayments and Conversions
for purposes of the foregoing, one for each Type or Interest Period).

         Section 2.9 Certain Notices. Notices by the Borrower to the
Administrative Agent of terminations or reductions of Commitments, of
borrowings, Conversions, Continuations and prepayments of Loans and of the
duration of Interest Periods shall be irrevocable and shall be effective only
if received by the Administrative Agent not later than 11:00 a.m. (New York,
New

CREDIT AGREEMENT - Page 39

<PAGE>   47

York, time) on the Business Day prior to the date of the relevant termination,
reduction, borrowing, Conversion, Continuation or prepayment or the first day
of such Interest Period specified below:

<TABLE>
<CAPTION>
                      Notice                                                    Number of
                      ------                                               Business Days Prior
                                                                           -------------------
         <S>                                                               <C>
         Terminations or Reductions of Commitments                                 1
         Borrowings of Loans which are Base Rate Loans                             2
         Borrowings of Loans which are Eurodollar Loans                            3
         Prepayments of Loans                                                      3
</TABLE>

Each such notice of termination or reduction shall specify the amount of the
Commitments to be terminated or reduced. Each such notice of borrowing,
Conversion, Continuation or prepayment shall specify the Loans to be borrowed,
Converted, Continued or prepaid and the amount (subject to Section 2.8 hereof)
and Type of the Loans to be borrowed, Converted, Continued or prepaid (and, in
the case of a Conversion, the Type of Loans to result from such Conversion) and
the date of borrowing, Conversion, Continuation or prepayment (which shall be a
Business Day). Each such notice of termination, reduction, borrowing,
Conversion, Continuation or prepayment shall be in the form of Exhibit C
hereto, appropriately completed as applicable. Each notice of borrowing (a
"Notice of Borrowing") (a) shall certify that all proceeds of the requested
Loans are, concurrently with the making of such Loans, being used by the
Borrower for the purpose specified in Section 2.10 and (b) shall be accompanied
by such other evidence as to use of the proceeds of such borrowing, as the
Administrative Agent may reasonably request from time to time. Each notice
which includes reference to the duration of an Interest Period shall specify
the Loans to which such Interest Period is to relate. The Administrative Agent
shall promptly notify the Lenders of the contents of each such notice. In the
event the Borrower fails to select the Type of Loan, or the duration of any
Interest Period for any Eurodollar Loan, within the time period and otherwise
as provided in this Section 2.9, such Loan (if outstanding as Eurodollar Loan)
will be automatically Converted into a Base Rate Loan on the last day of
preceding Interest Period for such Loan or (if outstanding as a Base Rate Loan)
will remain as, or (if not then outstanding) will be made as, a Base Rate Loan.
The Borrower may not borrow any Eurodollar Loans, Convert any Loans into
Eurodollar Loans or Continue any Loans as Eurodollar Loans if the interest rate
for such Eurodollar Loans would exceed the Maximum Rate.

         Section 2.10 Use of Proceeds.

         (a) Tranche A Loans. The Borrower agrees that all proceeds of the
Tranche A Loans shall be, promptly upon the Borrower's receipt thereof,
contributed as equity to the capital of, or loaned to, the Operating Subsidiary
that is to purchase (or that is to be reimbursed for the prior purchase of)
Nortel Networks Goods and Services with such proceeds and thereupon promptly
used by such Operating Subsidiary to finance (or to reimburse such Operating
Subsidiary for its prior payment of) the purchase price for such Nortel
Networks Goods and Services provided by Nortel Networks for the construction of
the Service Area Network, provided, however, that proceeds of Tranche A Loans
may not be used to finance (or to reimburse the prior payment of) the purchase

CREDIT AGREEMENT - Page 40

<PAGE>   48

price for Nortel Networks Goods and Services initially invoiced more than 12
months prior to the date of the making of such Loans, except that, on or prior
to February 29, 2000, proceeds of Tranche A Loans may be used to reimburse the
prior payment of the purchase price for Nortel Networks Goods and Services
initially invoiced at any time prior thereto.

         (b) Tranche B Loans. The Borrower agrees that all proceeds of the
Tranche B Loans shall be, promptly upon the Borrower's receipt thereof,
contributed as equity to the capital of, or loaned to, the Operating Subsidiary
that is to pay (or that is to be reimbursed for the prior payment of) Permitted
Third-Party Expenses with such proceeds and thereupon promptly used by such
Operating Subsidiary to pay (or to reimburse such Operating Subsidiary for its
prior payment of) such Permitted Third-Party Expenses up to an amount equal to
the Permitted Third-Party Expenses Borrowing Base then in effect, provided,
however, that (i) as of any date of determination, the aggregate principal
amount of the Tranche B Loans and the Tranche C Loans at any and all times used
to pay Permitted Third-Party Expenses shall not exceed the Permitted
Third-Party Expenses Borrowing Base then in effect and (ii) proceeds of Tranche
B Loans may not be used to pay (or to reimburse the prior payment of) any
Permitted Third-Party Expenses initially invoiced more than 12 months prior to
the date of the making of such Loans, except that, on or prior to February 29,
2000, proceeds of Tranche B Loans may be used to reimburse the prior payment of
Permitted Third-Party Expenses initially invoiced at any time prior thereto.

         (c) Tranche C Loans. The Borrower agrees that all proceeds of the
Tranche C Loans shall be, promptly upon the Borrower's receipt thereof, (i)
used by the Borrower to pay amounts payable under the Administrative Agent's
Letter on the Closing Date if and to the extent expressly permitted in the
Administrative Agent's Letter, (ii) used by the Borrower to pay interest
accrued on the Loans on or before the second anniversary of the Closing Date,
or (iii) contributed as equity to the capital of, or loaned to, the Operating
Subsidiary that is to pay (or that is to be reimbursed for the prior payment
of) Permitted Third-Party Expenses with such proceeds and thereupon promptly
used by such Operating Subsidiary to pay (or to reimburse such Operating
Subsidiary for its prior payment of) such Permitted Third-Party Expenses up to
an amount equal to the Permitted Third-Party Expenses Borrowing Base then in
effect, provided, however, that (A) as of any date of determination, the
aggregate principal amount of the Tranche B Loans and the Tranche C Loans at
any and all times used to pay Permitted Third-Party Expenses shall not exceed
the Permitted Third-Party Expenses Borrowing Base then in effect and (B)
proceeds of Tranche C Loans may not be used to pay (or to reimburse the prior
payment of) any amounts referred to in clauses (i), (ii) and (iii) preceding
initially invoiced more than 12 months prior to the date of the making of such
Loans, except that, on or prior to February 29, 2000, proceeds of Tranche C
Loans may be used to reimburse the prior payment of amounts referred to in
clauses (i), (ii) and (iii) preceding initially invoiced at any time prior
thereto.

         (d) Margin Stock. None of the proceeds of any Loan have been or will
be used to acquire any security in any transaction that is subject to Section
13 or 14 of the Exchange Act or to purchase or carry any margin stock (within
the meaning of Regulations T, U or X of the Board of Governors of the Federal
Reserve System).

CREDIT AGREEMENT - Page 41

<PAGE>   49

         Section 2.11 Fees

         (a) Subject to Section 13.12, the Borrower shall pay to the
Administrative Agent for the account of each applicable Lender a commitment fee
on the daily average unused or unfunded amount of each of such Lender's
Commitments, for the period from and including the date on which such Lender
(or its predecessor in interest with respect to Commitments assigned to such
Lender as to which a commitment fee has not previously been paid during the
applicable period) became a party hereto to but excluding the Tranche A
Commitment Termination Date, Tranche B Commitment Termination Date or the
Tranche C Commitment Termination Date, as the case may be, at the rate of
three-fourths of one percent (0.75%) per annum based on a 360 day year and the
actual number of days elapsed, which accrued commitment fees shall be payable
in arrears on each Quarterly Date and on the Tranche A Commitment Termination
Date, Tranche B Commitment Termination Date or the Tranche C Commitment
Termination Date, as the case may be; provided, however, that, notwithstanding
the foregoing, the commitment fees referred to in this Section 2.11(a)
preceding shall not commence to accrue until the date that is six months after
the Closing Date.

         (b) Subject to Section 13.12, the Borrower agrees to pay to the
Administrative Agent and Nortel Networks such additional fees as are specified
in the Administrative Agent's Letter, which fees shall be payable in such
amounts and on such dates as are specified therein.

         Section 2.12 Computations. Interest and fees payable by the Borrower
hereunder and under the other Loan Documents on all Loans shall be computed on
the basis of a year of 360 days and the actual number of days elapsed
(including the first day but excluding the last day) occurring in the period
for which payable unless, in the case of interest, such calculation would
result in a usurious rate, in which case interest shall be calculated on the
basis of a year of 365 or 366 days, as the case may be.

         Section 2.13 Termination or Reduction of Commitments.

         (a) Notwithstanding anything to the contrary contained in this
Agreement, each of the Commitments shall automatically terminate upon the
earlier to occur of (i) the occurrence of any Change in Control or (ii) any
sale, transfer or other disposition of the Service Area Network or any material
portion thereof.

         (b) Notwithstanding anything to the contrary contained in this
Agreement, on the date Holdings receives any net proceeds of any issuance of
Holdings Senior Notes, the Aggregate Commitments shall be reduced by an
aggregate amount such that, immediately after giving effect to such reduction,
the sum of (i) the aggregate outstanding principal amount of the Loans, plus
(ii) the aggregate outstanding principal amount of the Loans then previously
required to be prepaid or paid in accordance with Section 2.7 or Section 2.3,
respectively, plus (iii) the amount of the Aggregate Commitments does not
exceed $175,000,000. All reductions of the Aggregate Commitments pursuant to
this Section 2.13(b) shall be applied pro rata to reduce the Tranche A
Commitments, the Tranche B Commitments and the Tranche C Commitments (based
upon the outstanding principal amounts of such Commitments).

CREDIT AGREEMENT - Page 42

<PAGE>   50

         (c) Notwithstanding anything to the contrary contained in this
Agreement, each of the Tranche A Commitments, the Tranche B Commitments and the
Tranche C Commitments shall automatically be reduced, concurrently with the
making of any Tranche A Loans, Tranche B Loans or Tranche C Loans,
respectively, by an amount equal to the principal amount of such Tranche A
Loans, Tranche B Loans or Tranche C Loans, respectively, advanced; provided,
however, that, at the election of the Borrower and subject to the terms and
provisions of this Agreement, any of the Tranche A Loans, the Tranche B Loans
and/or the Tranche C Loans may be, at the election of the Borrower by its
giving of three Business Days' prior written notice of such election to the
Administrative Agent, increased by an amount not to exceed the amount by which
such Commitment was previously reduced pursuant to Section 2.13(b).

         (d) The Borrower shall have the right to terminate or reduce in part
the unused portion of the Tranche A Commitments, the Tranche B Commitments and
the Tranche C Commitments at any time and from time to time prior to the
Tranche A Commitment Termination Date, the Tranche B Commitment Termination
Date and the Tranche C Commitment Termination Date, respectively; provided,
however, that no such termination or reduction shall be effective unless the
Borrower shall have given notice of each such termination or reduction as
provided in Section 2.9, and each partial reduction of the Commitments shall be
in an aggregate amount at least equal to $3,000,000 or an integral multiple of
$100,000 in excess thereof.

         (e) Except as provided in Section 2.13(c), the Commitments may not be
reinstated after they have been terminated or increased after they have been
reduced.

                                   ARTICLE 3

                                    Payments

         Section 3.1 Method of Payment. All payments of principal, interest,
fees and other amounts to be made by the Borrower under this Agreement and the
other Loan Documents shall be made to the Administrative Agent at the Principal
Office for the account of each Lender's Applicable Lending Office in Dollars
and in immediately available funds, without setoff, deduction or counterclaim,
not later than 1:00 p.m. (New York, New York time) on the date on which such
payment shall become due (each such payment made after such time on such due
date to be deemed to have been made on the next succeeding Business Day). The
Borrower shall, at the time of making each such payment, specify to the
Administrative Agent the sums payable by the Borrower under this Agreement and
the other Loan Documents to which such payment is to be applied (and in the
event that the Borrower fails to so specify, or if an Event of Default has
occurred and is continuing, the Administrative Agent may apply such payment to
the Obligations in such order and manner as the Administrative Agent may elect,
subject to Section 3.2). Upon the occurrence and during the continuation of an
Event of Default, all proceeds of any Collateral and all other funds of the
Borrower or any Guarantor in the possession of the Administrative Agent or any
Lender, may be applied by the Administrative Agent to the Obligations in such
order and manner as the Administrative Agent may elect, subject to Section 3.2.
Each payment received by the Administrative Agent under this Agreement or any
other Loan Document for the account of a Lender shall be paid promptly to such
Lender, in immediately available funds, for the account of such

CREDIT AGREEMENT - Page 43

<PAGE>   51

Lender's Applicable Lending Office. Whenever any payment under this Agreement
or any other Loan Document shall be stated to be due on a day that is not a
Business Day, such payment may be made on the next succeeding Business Day, and
such extension of time shall in such case be included in the computation of the
payment of interest and commitment fee, as the case may be.

         Section 3.2 Pro Rata Treatment. Except to the extent otherwise
provided in this Agreement: (a) each Loan shall be made by the Lenders under
Section 2.1, each payment of commitment fees under Section 2.11(a) shall be
made for the account of the Lenders, and each termination or reduction of the
Commitments under Section 2.13 shall be applied to the Commitments of the
Lenders, pro rata according to the respective unused Commitments; (b) the
making, Conversion and Continuation of Loans of a particular Type (other than
Conversions provided for by Section 4.4) shall be made pro rata among the
Lenders holding Loans of such Type according to the amounts of their respective
Commitments; (c) each payment and prepayment by the Borrower of principal of or
interest on Loans of a particular Type shall be made to the Administrative
Agent for the account of the Lenders holding Loans of such Type pro rata in
accordance with the respective unpaid principal amounts of such Loans held by
such Lenders; and (d) Interest Periods for Loans of a particular Type shall be
allocated among the Lenders holding Loans of such Type pro rata according to
the respective principal amounts held by such Lenders.

         Section 3.3 Sharing of Payments, Etc. If a Lender shall obtain payment
of any principal of or interest on any of the Obligations due to such Lender
hereunder through the exercise of any right of setoff, banker's lien,
counterclaim or similar right, or otherwise, it shall promptly purchase from
the other Lenders participations in the Obligations held by the other Lenders
in such amounts, and make such adjustments from time to time, as shall be
equitable to the end that all the Lenders shall share pro rata in accordance
with the unpaid principal and interest on the Obligations then due to each of
them. To such end, all of the Lenders shall make appropriate adjustments among
themselves (by the resale of participations sold or otherwise) if all or any
portion of such excess payment is thereafter rescinded or must otherwise be
restored. Each of the Loan Parties agrees, to the fullest extent it may
effectively do so under applicable law, that any Lender so purchasing a
participation in the Obligations by the other Lenders may exercise all rights
of setoff, banker's lien, counterclaim or similar rights with respect to such
participation as fully as if such Lender were a direct holder of Obligations in
the amount of such participation. Nothing contained herein shall require any
Lender to exercise any such right or shall affect the right of any Lender to
exercise, and retain the benefits of exercising, any such right with respect to
any other indebtedness, liability or obligation of any of the Loan Parties.

         Section 3.4 Non-Receipt of Funds by the Administrative Agent. Unless
the Administrative Agent shall have been notified by a Lender or the Borrower
(the "Payor") prior to the date on which such Lender is to make payment to the
Administrative Agent of the proceeds of a Loan to be made by it hereunder or
the Borrower is to make a payment to the Administrative Agent for the account
of one or more of the Lenders, as the case may be (such payment being herein
called the "Required Payment"), which notice shall be effective upon receipt,
that the Payor does not intend to make the Required Payment to the
Administrative Agent, the Administrative Agent may assume that the Required
Payment has been made and may, in reliance upon such assumption (but shall not
be required to), make the amount thereof available to the intended recipient on
such date and, if the

CREDIT AGREEMENT - Page 44

<PAGE>   52

Payor has not in fact made the Required Payment to the Administrative Agent,
the recipient of such payment shall, on demand, pay to the Administrative Agent
the amount made available to it together with interest thereon in respect of
the period commencing on the date such amount was so made available by the
Administrative Agent until the date the Administrative Agent recovers such
amount at a rate per annum equal to the Federal Funds Rate for such period.

         Section 3.5 Taxes.

         (a) All payments by the Borrower and/or any Guarantor of principal of
and interest on the Loans and of all fees and other amounts payable under the
Loan Documents shall be made free and clear of, and without withholding or
deduction by reason of, any present or future taxes, levies, duties, imposts,
assessments or other charges levied or imposed by any Governmental Authority
(other than franchise taxes and taxes on the overall net income of any Lender).
If any such taxes, levies, duties, imposts, assessments or other charges are so
levied or imposed, the Borrower will (i) make additional payments in such
amounts so that every net payment of principal of and interest on the Loans and
of all other amounts payable by it under the Loan Documents, after withholding
or deduction for or on account of any such present or future taxes, levies,
duties, imposts, assessments or other charges (including any tax imposed on or
measured by net income of a Lender attributable to payments made to or on
behalf of a Lender pursuant to this Section 3.5 and any penalties or interest
attributable to such payments), will not be less than the amount provided for
herein or therein absent such withholding or deduction (provided that the
Borrower shall not have any obligation to pay such additional amounts to any
Lender to the extent that such taxes, levies, duties, imposts, assessments or
other charges are levied or imposed by reason of the failure of such Lender to
comply with the provisions of Section 3.6), (ii) make such withholding or
deduction and (iii) remit the full amount deducted or withheld to the relevant
Governmental Authority in accordance with applicable law. Without limiting the
generality of the foregoing, the Borrower will, upon written request of any
Lender, reimburse each such Lender for the amount of (A) such taxes, levies,
duties, imports, assessments or other charges so levied or imposed by any
Governmental Authority and paid by such Lender as a result of payments made by
the Borrower under or with respect to the Loans other than such taxes, levies,
duties, imports, assessments and other charges previously withheld or deducted
by the Borrower which have previously resulted in the payment of the required
additional amount to such Lender, and (B) such taxes, levies, duties,
assessments and other charges so levied or imposed with respect to any Lender
reimbursement under the foregoing clause (A), so that the net amount received
by such Lender (net of payments made under or with respect to the Loans) after
such reimbursement will not be less than the net amount such Lender would have
received if such taxes, levies, duties, assessments and other charges on such
reimbursement had not been levied or imposed. The Borrower shall furnish
promptly to the Administrative Agent for distribution to each affected Lender,
as the case may be, upon request of such Lender, official receipts evidencing
any such payment, withholding or reduction.

         (b) The Borrower will indemnify the Administrative Agent and each
Lender (without duplication) against, and reimburse the Administrative Agent
and each Lender for, all present and future taxes, levies, duties, imposts,
assessments or other charges (including interest and penalties) levied or
collected (whether or not legally or correctly imposed, assessed, levied or
collected), excluding, however, any taxes imposed on the overall net income of
the Administrative Agent or

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<PAGE>   53

such Lender or any lending office of the Administrative Agent or such Lender by
any jurisdiction in which the Administrative Agent or such Lender or any such
lending office is located, on or in respect of this Agreement, any of the Loan
Documents or the Obligations or any portion thereof (the "reimbursable taxes").
Any such indemnification shall be on an after-tax basis, taking into account
any such reimbursable taxes imposed on the amounts paid as indemnity.

         (c) Without prejudice to the survival of any other term or provision
of this Agreement, the obligations of the Borrower and the Guarantors under
this Section 3.5 shall survive the payment of the Loans and the other
Obligations and termination of the Commitments.

         Section 3.6 Withholding Tax Exemption. Each Lender that is not
incorporated or otherwise formed under the laws of the U.S. or a state thereof
agrees that it will, prior to or on or about the Closing Date or the date upon
which it initially becomes a party to this Agreement and if it is legally able
to do so, deliver to the Borrower and the Administrative Agent two duly
completed copies of U.S. Internal Revenue Service Form W-8ECI or W-8BEN or
other equivalent successor form, as appropriate, certifying in any case that
such Lender is entitled to receive payments from the Borrower under any Loan
Document without deduction or withholding of any U.S. federal income taxes.
Each Lender which so delivers a Form W-8ECI or W-8BEN or other equivalent
successor form, as appropriate, further undertakes to deliver to the Borrower
and the Administrative Agent two additional copies of such form (or a successor
form) on or before the date such form expires or becomes obsolete or after the
occurrence of any event requiring a change in the most recent form so delivered
by it, and such amendments thereto or extensions or renewals thereof as may be
reasonably requested by the Borrower or the Administrative Agent, in each case
certifying that such Lender is entitled to receive payments from the Borrower
under any Loan Document without deduction or withholding of any U.S. federal
income taxes, unless an event (including without limitation any change in
treaty, law or regulation) has occurred prior to the date on which any such
delivery would otherwise be required which renders all such forms inapplicable
or which would prevent such Lender from duly completing and delivering any such
form with respect to it and such Lender advises the Borrower and the
Administrative Agent that it is not capable of receiving such payments without
any deduction or withholding of U.S. federal income tax.

         Section 3.7 Reinstatement of Obligations. Notwithstanding anything to
the contrary contained in this Agreement or any other Loan Document, if the
payment of any amount of principal of or interest with respect to the Loans or
any other amount of the Obligations, or any portion thereof, is rescinded,
voided or must otherwise be refunded by the Administrative Agent or any Lender
upon the insolvency, bankruptcy or reorganization of any Loan Party or
otherwise for any reason whatsoever, then each of (a) the Obligations, (b) the
Loan Documents (including, without limitation, this Agreement, the Notes and
the Security Documents), (c) the indebtedness, liabilities and obligations of
the Borrower and any other Loan Parties and (d) all Liens for the benefit of
the Administrative Agent and the Lenders created under or evidenced by the Loan
Documents, will be automatically reinstated and become automatically effective
and in full force and effect, all to the extent that and as though such payment
so rescinded, voided or otherwise refunded had never been made.

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<PAGE>   54

         Section 3.8 No Force Majeure, Disputes. The obligations of the
Borrower and the other Loan Parties (as applicable), or any one or more of
them, to pay all amounts due under the Loans and the other Obligations shall
not be affected by (a) any set-off, counterclaim, recoupment, deduction,
abatement, suspension, diminution, reduction, defense or other right which the
Borrower or any other Loan Party may have against the Vendor for any reason
whatsoever arising under or pursuant to the Supply Agreement or otherwise
relating to the purchase of goods or services from the Vendor, (b) any defect
in the condition, design, operation or fitness for use of, or any damage to or
loss or destruction of, any equipment or material or service provided by the
Vendor, (c) any insolvency, bankruptcy, reorganization or similar proceedings
by or against the Borrower or any other Loan Party or affecting any of its
Properties, (d) any action of any Governmental Authority or any damage to or
destruction of or any taking of the Property of the Borrower or any other Loan
Party or any part thereof, (e) any change, waiver, extension, indulgence or
failure to perform or comply with, or other action or omission herein or in the
other Loan Documents (except for express written modifications to this
Agreement or other Loan Documents as and in the manner permitted under this
Agreement or the other Loan Documents), (f) any dissolution of the Borrower or
any other Loan Party, (g) any inability or illegality with respect to the use
or ownership of the Property of the Borrower or any other Loan Party, (h) any
failure to obtain, or expiration, suspension or other termination of, or
interruption to, any required licenses, permits, consents, authorizations,
approvals or other legal requirements, (i) the invalidity or unenforceability
of any of the Loan Documents or any other infirmity therein or any lack of
power or authority of the Administrative Agent or any Lender or the Borrower or
any other Loan Party, or (j) any other event or circumstance whatsoever,
whether or not similar to any of the foregoing and whether or not the Borrower
or any other Loan Party shall have notice or knowledge of any of the foregoing,
it being the intention of the Administrative Agent and the Lenders and the
Borrower and the other Loan Parties that the Obligations of the Borrower and/or
the other Loan Parties (as applicable) shall be absolute and unconditional and
shall be separate and independent covenants and agreements and shall continue
unaffected unless the requirements to pay or perform the same shall have been
terminated pursuant to an express provision thereof or of any of the other Loan
Documents.

                                   ARTICLE 4

                        Yield Protection and Illegality

         Section 4.1 Additional Costs.

         (a) The Borrower shall pay directly to each Lender from time to time,
promptly upon the request of such Lender, the costs incurred by such Lender
which such Lender determines are attributable to its making or maintaining of
any Eurodollar Loans or its obligation to make any of such Loans, or any
reduction in any amount receivable by such Lender hereunder in respect of any
such Loans or obligations (such increases in costs and reductions in amounts
receivable being herein called "Additional Costs"), resulting from any
Regulatory Change which:

                  (i) changes the basis of taxation of any amounts payable to
         such Lender under this Agreement or its Notes in respect of any of
         such Loans (other than taxes imposed on the overall net income of such
         Lender or its Applicable Lending Office for any of such Loans

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<PAGE>   55

         by the jurisdiction in which such Lender has its principal office or
         such Applicable Lending Office);

                  (ii) imposes or modifies any reserve, special deposit,
         minimum capital, capital ratio or similar requirement relating to any
         extensions of credit or other assets of, or any deposits with or other
         liabilities or commitments of, such Lender (including any of such
         Loans or any deposits referred to in the definition of "Eurodollar
         Rate" in Section 1.1 hereof, but excluding the Reserve Requirement to
         the extent it is included in the calculation of the Adjusted
         Eurodollar Rate); or

                  (iii) imposes any other condition affecting this Agreement or
         the Notes or any extensions of credit or liabilities or commitments
         contemplated hereunder or thereunder.

Each Lender will notify the Borrower (with a copy to the Administrative Agent)
of any event occurring after the Closing Date which will entitle such Lender to
compensation pursuant to this Section 4.1(a) as promptly as practicable after
it obtains knowledge thereof and determines to request such compensation, and
(if so requested by the Borrower) will designate a different Applicable Lending
Office for the Eurodollar Loans of such Lender if such designation will avoid
the need for, or reduce the amount of, such compensation and will not, in the
sole opinion of such Lender, violate any law, rule or regulation or be in any
way disadvantageous to such Lender, provided that such Lender shall have no
obligation to so designate an Applicable Lending Office located in the U.S.
Each Lender will furnish the Borrower with a certificate setting forth the
basis and the amount of each request of such Lender for compensation under this
Section 4.1(a). If any Lender requests compensation from the Borrower under
this Section 4.1(a), the Borrower may, by notice to such Lender (with a copy to
the Administrative Agent), suspend the obligation of such Lender to make or
Continue making, or Convert Base Rate Loans into, Eurodollar Loans until the
Regulatory Change giving rise to such request ceases to be in effect (in which
case the provisions of Section 4.4 hereof shall be applicable).

         (b) Without limiting the effect of the foregoing provisions of this
Section 4.1, in the event that, by reason of any Regulatory Change, any Lender
either (i) incurs Additional Costs based on or measured by the excess above a
specified level of the amount of a category of deposits or other liabilities of
such Lender which includes deposits by reference to which the interest rate on
Eurodollar Loans is determined as provided in this Agreement or a category of
extensions of credit or other assets of such Lender which includes Eurodollar
Loans or (ii) becomes subject to restrictions on the amount of such a category
of liabilities or assets which it may hold, then, if such Lender so elects by
notice to the Borrower (with a copy to the Administrative Agent), the
obligation of such Lender to make or Continue making, or Convert Base Rate
Loans into, Eurodollar Loans hereunder shall be suspended until such Regulatory
Change ceases to be in effect (in which case the provisions of Section 4.4
hereof shall be applicable).

         (c) Determinations and allocations by any Lender for purposes of this
Section 4.1 of the effect of any Regulatory Change on its costs of maintaining
its obligation to make Loans or of making or maintaining Loans or on amounts
receivable by it in respect of Loans and of the additional amounts required to
compensate such Lender in respect of any Additional Costs, shall be conclusive

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<PAGE>   56

in the absence of manifest error, provided that such determinations and
allocations are made on a reasonable basis. Notwithstanding anything to the
contrary contained herein, the Borrower shall not be required to make any
payment of Additional Costs to any Lender pursuant to this Section 4.1 with
respect to Additional Costs relating to any period of time which is more than
180 days prior to such Lender's request for such Additional Costs, provided
that the foregoing provisions of this sentence shall not apply to Additional
Costs attributable to any Regulatory Change which takes effect retroactively.

         Section 4.2 Limitation on Types of Loans. Anything herein to the
contrary notwithstanding, if with respect to any Eurodollar Loans for any
Interest Period therefor:

         (a) the Administrative Agent determines (which determination shall be
conclusive absent manifest error) that quotations of interest rates for the
relevant deposits referred to in the definition of "Eurodollar Rate" in Section
1.1 hereof are not being provided in the relative amounts or for the relative
maturities for purposes of determining the rate of interest for such Loans as
provided in this Agreement; or

         (b) the Required Lenders determine (which determination shall be
conclusive absent manifest error) and notify the Administrative Agent that the
relevant rates of interest referred to in the definition of "Eurodollar Rate"
or "Adjusted Eurodollar Rate" in Section 1.1 hereof on the basis of which the
rate of interest for such Loans for such Interest Period is to be determined do
not accurately reflect the cost to the Lenders of making or maintaining such
Loans for such Interest Period;

then the Administrative Agent shall give the Borrower prompt notice thereof
and, so long as such condition remains in effect, the Lenders shall be under no
obligation to make Eurodollar Loans or to Convert Base Rate Loans into
Eurodollar Loans and the Borrower shall, on the last day(s) of the then current
Interest Period(s) for the outstanding Eurodollar Loans, either prepay such
Loans or Convert such Loans into Base Rate Loans in accordance with the terms
of this Agreement.

         Section 4.3 Illegality. Notwithstanding any other provision of this
Agreement, in the event that it becomes unlawful for any Lender or its
Applicable Lending Office to (a) honor its obligation to make Eurodollar Loans
or (b) maintain Eurodollar Loans, then such Lender shall promptly notify the
Borrower (with a copy to the Administrative Agent) thereof and such Lender's
obligation to make or maintain Eurodollar Loans and to Convert Base Rate Loans
into Eurodollar Loans hereunder shall be suspended until such time as such
Lender may again make and maintain Eurodollar Loans (in which case the
provisions of Section 4.4 hereof shall be applicable).

         Section 4.4 Treatment of Affected Loans. If the obligation of any
Lender to make or Continue, or to Convert Base Rate Loans into, Eurodollar
Loans is suspended pursuant to Section 4.1 or 4.3 hereof, such Lender's
Eurodollar Loans shall be automatically Converted into Base Rate Loans on the
last day(s) of the then current Interest Period(s) for the Eurodollar Loans
(or, in the case of a Conversion required by Section 4.1(b) or 4.3 hereof, on
such earlier date as such Lender may specify to the Borrower with a copy to the
Administrative Agent) and, unless and until such Lender

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gives notice as provided below that the circumstances specified in Section 4.1
or 4.3 hereof which gave rise to such Conversion no longer exist:

         (a) to the extent that such Lender's Eurodollar Loans have been so
Converted, all payments and prepayments of principal which would otherwise be
applied to such Lender's Eurodollar Loans shall be applied instead to its Base
Rate Loans; and

         (b) all Loans which would otherwise be made or Continued by such
Lender as Eurodollar Loans shall be made as or Converted into Base Rate Loans
and all Loans of such Lender which would otherwise be Converted into Eurodollar
Loans shall be Converted instead into (or shall remain as) Base Rate Loans.

If such Lender gives notice to the Borrower that the circumstances specified in
Section 4.1 or 4.3 hereof which gave rise to the Conversion of such Lender's
Eurodollar Loans pursuant to this Section 4.4 no longer exist (which such
Lender agrees to do promptly upon such circumstances ceasing to exist) at a
time when Eurodollar Loans are outstanding, such Lender's Base Rate Loans shall
be automatically Converted, on the first day(s) of the next succeeding Interest
Period(s) for such outstanding Eurodollar Loans, to the extent necessary so
that, after giving effect thereto, all Loans held by the Lenders holding
Eurodollar Loans and by such Lender are held pro rata (as to principal amounts,
Types and Interest Periods) in accordance with their respective Commitments.

         Section 4.5 Compensation. The Borrower shall pay to the Administrative
Agent for the account of each Lender, promptly upon the request of such Lender
through the Administrative Agent, such amount or amounts as shall be sufficient
(in the reasonable opinion of such Lender) to compensate it for any loss, cost
or expense incurred by it as a result of:

         (a) Any payment, prepayment or Conversion of a Eurodollar Loan for any
reason (including, without limitation, the acceleration of the outstanding
Loans pursuant to Section 11.2) on a date other than the last day of an
Interest Period for such Loan; or

         (b) Any failure by the Borrower for any reason (including, without
limitation, the failure of any conditions precedent specified in Article 6 to
be satisfied) to borrow, Convert or prepay a Eurodollar Loan on the date for
such borrowing, Conversion or prepayment specified in the relevant notice of
borrowing, prepayment or Conversion under this Agreement.

         Section 4.6 Capital Adequacy. If, after the Closing Date, any Lender
shall have determined that the adoption or implementation of any applicable
law, rule or regulation regarding capital adequacy (including, without
limitation, any law, rule or regulation implementing the Basle Accord), or any
change therein, or any change in the interpretation or administration thereof
by any central bank or other Governmental Authority charged with the
interpretation or administration thereof, or compliance by such Lender (or its
parent) with any guideline, request or directive regarding capital adequacy
(whether or not having the force of law) of any central bank or other
Governmental Authority (including, without limitation, any guideline or other
requirement implementing the Basle Accord), has or would have the effect of
reducing the rate of return on such Lender's (or its parent's) capital as a
consequence of its obligations hereunder or the transactions

CREDIT AGREEMENT - Page 50

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contemplated hereby to a level below that which such Lender (or its parent)
could have achieved but for such adoption, implementation, change or compliance
(taking into consideration such Lender's policies with respect to capital
adequacy) by an amount reasonably deemed by such Lender to be material, then
from time to time, within ten Business Days after demand by such Lender (with a
copy to the Administrative Agent), the Borrower shall pay to such Lender such
additional amount or amounts as will compensate such Lender (or its parent) for
such reduction. A certificate of such Lender claiming compensation under this
Section 4.6 and setting forth the additional amount or amounts to be paid to it
hereunder shall be conclusive absent manifest error, provided that the
determination thereof is made on a reasonable basis. In determining such amount
or amounts, such Lender may use any reasonable averaging and attribution
methods. Notwithstanding anything to the contrary contained herein, the
Borrower shall not be required to make any payment of additional amounts to any
Lender pursuant to this Section 4.6 with respect to additional amounts relating
to any period of time which is more than 180 days prior to such Lender's
request for such additional amounts, provided that the foregoing provisions of
this sentence shall not apply to additional amounts attributable to any
Regulatory Change which takes effect retroactively.

         Section 4.7 Additional Interest on Eurodollar Loans. Without
duplication of Section 2.4 or amounts directly included in the definition of
the term "Adjusted Eurodollar Rate", the Borrower shall pay, directly to each
Lender from time to time, additional interest on the unpaid principal amount of
each Eurodollar Loan held by such Lender, from the date of the making of such
Eurodollar Loan until such principal amount is paid in full, at an interest
rate per annum determined by such Lender in good faith equal to the positive
remainder (if any) of (a) the Adjusted Eurodollar Rate applicable to such
Eurodollar Loan minus (b) the Eurodollar Rate applicable to such Eurodollar
Loan. Each payment of additional interest pursuant to this Section 4.7 shall be
payable by the Borrower on each date upon which interest is payable on such
Eurodollar Loan pursuant to Section 2.4(b); provided, however, that the
Borrower shall not be obligated to make any such payment of additional interest
until the first Business Day after the date when the Borrower has been informed
(i) that such Lender is subject to a Reserve Requirement and (ii) of the amount
of such Reserve Requirement (after which time the Borrower shall be obligated
to make all such payments of additional interest, including, without
limitation, such payment of additional interest that otherwise would have been
payable by the Borrower on or prior to such time had the Borrower been earlier
informed).

         Section 4.8 Replacement of Lenders. If at any time a Lender, other
than Nortel Networks, becomes a Gross Up Lender, the Borrower shall have the
right to replace such Lender with another Person; provided that (a) such other
Person shall be an Eligible Assignee and such other Person shall execute an
Assignment and Acceptance, (b) neither the Administrative Agent nor any Lender
shall have any obligation to the Borrower to find such other Person, (c) in the
event of a replacement of a Gross Up Lender, in order for the Borrower to be
entitled to replace such Lender, such replacement must take place no later than
180 days after the date the Gross Up Lender shall notify the Borrower and the
Administrative Agent of its desire to be paid any amounts pursuant to Section
3.5, 4.1 or 4.6, and (d) if the Borrower replaces one Gross Up Lender, it must
replace all Gross Up Lenders or replace all Gross Up Lenders on a pro rata
basis. Each Lender, other than Nortel Networks, agrees to its replacement at
the option of the Borrower pursuant to this Section 4.8 and in accordance with
Section 13.8; provided that the successor Lender shall purchase without

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recourse such Lender's interest in the Obligations of the Borrower to such
Lender for cash in an aggregate amount equal to the aggregate unpaid principal
thereof, all unpaid interest accrued thereon, all unpaid commitment fees
accrued for the account of such Lender, any breakage costs incurred by the
selling Lender because of the prepayment of any Eurodollar Loans, all other
fees (if any) applicable thereto and all other amounts (including any amounts
under this Article 4) then owing to such Lender hereunder or under any other
Loan Document and the Loan Parties shall execute a release addressed to such
Lender releasing such Lender from all claims arising in connection with the
Loan Documents.

                                   ARTICLE 5

                                    Security

         Section 5.1 Collateral. To secure the full and complete payment and
performance of the Obligations, the Borrower, Holdings and the Operating
Subsidiaries will (as applicable), and will cause each of the Loan Parties (as
applicable) to, grant to the Administrative Agent for the benefit of the
Administrative Agent and the Lenders a perfected, first priority Lien on all of
its right, title and interest in and to the Collateral, whether now owned or
hereafter acquired, pursuant to the Security Documents, including, without
limitation, the following:

         (a) all Capital Stock of the Borrower and the Subsidiaries of Holdings
and the Borrower owned by Holdings, the Borrower or any Subsidiary of Holdings
or the Borrower, other than Capital Stock of Unrestricted Subsidiaries of
Holdings;

         (b) all of the Property (as such Property is more specifically
described in the Security Documents), including tangible and intangible
property and real and personal property, of Holdings and the Borrower and each
Subsidiary of Holdings or the Borrower, other than Property of the Unrestricted
Subsidiaries of Holdings, including, without limitation, the following:
Investments (including certificates of deposit); accounts; inventory
(including, without limitation, work in process); equipment; deposit accounts
(including cash collateral accounts); brokerage accounts; instruments;
Operating Assets; the Sprint Agreements; contract rights (including, without
limitation, all contracts relating to the construction or operation of the
Service Area Network, including rights of way, easements, leases and all
related contracts, and all consents and waivers necessary or appropriate from
all parties to such contracts, including, without limitation, all consents and
waivers necessary or appropriate to permit the collateral assignment of or
security interest granted in such contracts); customer deposits in connection
with purchase orders; general intangibles; real Property and interests therein
(if and to the extent required pursuant to Section 5.4); instruments; chattel
paper; Permits; Intellectual Property; and intercompany Debt (including,
without limitation, Debt of the Borrower or any of its Subsidiaries owed to or
held by Holdings); provided, however, that Holdings shall not be required to
grant to the Administrative Agent a security interest in (i) any identifiable
cash proceeds of the issuance of the Holdings Public Offering or any
identifiable cash proceeds of the issuance of the Holdings Senior Notes or (ii)
any dividends, distributions or other amounts received by Holdings from its
Unrestricted Subsidiaries, in each case (i.e., as to each of clause (i) and
clause (ii) preceding) if and to the extent (but only if and to the extent)
that such proceeds (A) are not, and are not required to be, contributed or
otherwise paid or transferred to the

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Borrower or any Subsidiary of the Borrower and (B) are held in a segregated
deposit, securities or similar account of Holdings and are not commingled with
other cash, securities or properties of Holdings; and

         (c) all cash and non-cash proceeds and products of any of the
foregoing.

         Section 5.2 Guaranties. (a) Holdings and each of the Operating
Subsidiaries will Guarantee the payment and performance of the Obligations
pursuant to the Guaranties, and (b) the Borrower, Holdings and the Operating
Subsidiaries will cause (i) Holdings, (ii) each of the Subsidiaries of Holdings
(whether owned as of the Closing Date or thereafter organized or created),
other than Unrestricted Subsidiaries of Holdings, and (iii) each of the
Subsidiaries of the Borrower (whether owned as of the Closing Date or
thereafter organized or created) to Guarantee the payment and performance of
the Obligations pursuant to the Guaranties.

         Section 5.3 New Subsidiaries; Additional Capital Stock.
Contemporaneously with the creation or acquisition of any Subsidiary of
Holdings or the Borrower after the Closing Date other than an Unrestricted
Subsidiary of Holdings, the Borrower, Holdings and the Operating Subsidiaries
shall (as applicable):

         (a) grant or cause to be granted to the Administrative Agent, for the
benefit of itself and the Lenders, a perfected, first priority security
interest in all Capital Stock of such Subsidiary owned by Holdings or the
Borrower or any Subsidiary of Holdings or the Borrower (to the extent such
Capital Stock was not previously pledged to the Administrative Agent);

         (b) cause each such Subsidiary to Guarantee the payment and
performance of the Obligations by executing and delivering to the
Administrative Agent a Guaranty or a joinder therein acceptable to the
Administrative Agent; and

         (c) cause each such Subsidiary to execute and deliver to the
Administrative Agent a Security Agreement and such other Security Documents, in
form and substance acceptable to the Administrative Agent, as the
Administrative Agent may request to grant the Administrative Agent, for the
benefit of itself and the Lenders, a perfected, first priority Lien on all
Property of such Subsidiary.

Contemporaneously with the issuance of any additional Capital Stock of the
Borrower or any Subsidiary of Holdings or the Borrower after the Closing Date,
other than Capital Stock of an Unrestricted Subsidiary of Holdings, the
Borrower, Holdings and the Operating Subsidiaries shall, or shall cause
Holdings or the appropriate Subsidiary of Holdings or the Borrower to (as
applicable), grant or cause to be granted to the Administrative Agent, for the
benefit of the Administrative Agent and the Lenders, a perfected, first
priority security interest in all Capital Stock or other ownership interests in
the Borrower or any Subsidiary of Holdings or the Borrower, other than Capital
Stock of an Unrestricted Subsidiary of Holdings, owned by the Borrower or
Holdings or any such Subsidiary of Holdings or the Borrower (to the extent such
Capital Stock or other ownership interests are already not so pledged to the
Administrative Agent). Each of the Borrower, Holdings and the Operating
Subsidiaries covenants that none of the Capital Stock to be pledged in
accordance with

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this Section 5.3 shall be subject to any transfer restriction, shareholders'
agreement or other restriction except for such restrictions under applicable
securities laws, such restrictions existing as of the Closing Date which have
been disclosed to the Administrative Agent in the Security Documents and such
restrictions, if any, as may be reasonably acceptable to the Administrative
Agent. In connection with and in addition to the foregoing, each of the Loan
Parties shall, and shall cause each other appropriate Person (as applicable)
to, execute and/or deliver such further agreements, documents and instruments
(including, without limitation, stock certificates, stock powers and financing
statements) as the Administrative Agent may reasonably request in order for it
to obtain and maintain the perfected, first priority Liens to be granted in
accordance with this Section 5.3.

         Section 5.4 Mortgaged Properties; Landlord Subordinations or Waivers.
The Borrower, Holdings and the Operating Subsidiaries shall, and shall cause
each of the other Loan Parties to, on the Closing Date (with respect to any fee
real Property owned on such date) or contemporaneously with the acquisition of
any fee real Property (with respect to any fee real Property acquired after the
Closing Date), execute, acknowledge and deliver to the Administrative Agent a
Mortgage or an amendment or modification to an existing Mortgage covering all
fee real Property owned on the Closing Date or acquired by the Borrower or any
such Loan Party subsequent to the Closing Date, together with evidence
satisfactory to the Administrative Agent and its counsel that the Mortgage
creates a valid, first priority Lien on the fee estate, in favor of the
Administrative Agent for the benefit of the Administrative Agent and the
Lenders, a mortgagee policy of title insurance insuring the Administrative
Agent's first priority Lien status created by each such Mortgage, a current
survey certified to the Administrative Agent and the Lenders, an appraisal
complying with all applicable regulatory requirements, and an environmental
survey acceptable to the Administrative Agent, all of which shall be in form
and substance reasonably satisfactory to the Administrative Agent; provided,
however, that, with respect to any particular parcel of real Property having a
fair market value (inclusive of fixtures) of $250,000 or less, a mortgagee
policy of title insurance and a current survey shall not be required to be
provided if the aggregate fair market value (inclusive of fixtures) of all real
Property as to which the same have not been provided does not exceed
$1,000,000; provided, further, however, that a mortgagee policy of title
insurance shall be required to be provided with respect to each real Property
as to which an owner's policy of title insurance has been or is being obtained
and a current survey shall be required to be provided if available. In
addition, if reasonably requested by the Administrative Agent, the Borrower,
Holdings and the Operating Subsidiaries shall, and shall cause each of the
other Loan Parties with an interest in such Property to, provide the
Administrative Agent with a current environmental assessment of such Property
in form and substance reasonably satisfactory to the Administrative Agent. With
respect to each lease of real Property as to which the Borrower or any other
Loan Party is lessee, the Borrower, Holdings and the Operating Subsidiaries
will, and will cause each of the other Loan Parties to, obtain subordinations
or waivers of landlord's Liens from each lessor and other agreements from such
lessor and its lenders necessary or appropriate to ensure Administrative
Agent's perfected, first priority Lien on the Collateral or Property affected
thereby, the Administrative Agent's access to such Collateral or Property and
the right of the Administrative Agent, the Lenders or their designee to succeed
to the rights of the Borrower or such other Loan Party that is the lessee under
such lease, in each case in form and substance reasonably satisfactory to the
Administrative Agent.

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         Section 5.5 Setoff. If an Event of Default shall have occurred and be
continuing, each Lender is hereby authorized at any time and from time to time,
without notice to the Borrower or any other Loan Party (any such notice being
hereby expressly waived by the Borrower and the other Loan Parties), to set off
and apply any and all deposits (general or special, time or demand, provisional
or final excluding any trust accounts) at any time held and other indebtedness
at any time owing by such Lender to or for the credit or the account of the
Borrower or any Guarantor against any and all of the Obligations of the
Borrower or such Guarantor now or hereafter existing under this Agreement, such
Lender's Note or any other Loan Document, irrespective of whether or not the
Administrative Agent or such Lender shall have made any demand under this
Agreement, such Lender's Note or any such other Loan Document and although such
Obligations may be unmatured. Each Lender agrees promptly to notify the
Borrower (with a copy to the Administrative Agent) after any such setoff and
application, provided that the failure to give such notice shall not affect the
validity of such setoff and application. The rights and remedies of each Lender
hereunder are in addition to other rights and remedies (including, without
limitation, other rights of setoff) which such Lender may have.

         Section 5.6 Further Assurances. In addition to the foregoing, the
Borrower, Holdings and the Operating Subsidiaries will, and will cause each of
the other Loan Parties (as applicable) to, execute and/or deliver such further
agreements, documents and instruments (including, without limitation, Security
Documents and financing statements) as the Administrative Agent may reasonably
request from time to time in order for it to obtain and maintain valid,
perfected first priority Liens required to be granted to secure the payment and
performance of the Obligations in accordance with this Article 5.

                                   ARTICLE 6

                              Conditions Precedent

         Section 6.1 Initial Extension of Credit. The obligation of each Lender
to make its initial Loan under this Agreement is subject to completion of
Lenders' due diligence review of each of the Loan Parties and the receipt by
the Administrative Agent, on or before the Closing Date, of all of the
following in form and substance satisfactory to the Administrative Agent and,
in the case of actions to be taken, the taking of the following required
actions and evidence that such actions have been taken to the satisfaction of
the Administrative Agent:

         (a) Resolutions. Resolutions of the Board of Directors or equivalent
governing body (as applicable) certified by the Secretary or an Assistant
Secretary (or equivalent officer or representative) of each Loan Party which
authorize the execution, delivery and performance by such Loan Party of the
Loan Documents to which it is or is to be a party;

         (b) Incumbency Certificate. A certificate of incumbency certified by
the Secretary or an Assistant Secretary (or equivalent officer or
representative) of each Loan Party certifying as to the name of each officer or
other representative of such Loan Party (i) who is authorized to sign the Loan
Documents to which it is or is to be a party (including any certificates
contemplated therein), together with specimen signatures of each such officer
or other representative, and (ii) who will, until

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replaced by other officers or representatives duly authorized for that purpose,
act as its representative for the purposes of signing documents and giving
notices and other communications in connection with the Loan Documents and the
transactions contemplated thereby;

         (c) Certificate of Incorporation, Etc. The certificate of
incorporation, articles of incorporation, certificate of formation, certificate
of organization, partnership agreement or other analogous constitutional
documents of each Loan Party certified by the Secretary of State or other
applicable Governmental Authority of the state of incorporation, formation or
organization of such entity and dated as of a Current Date;

         (d) Bylaws, Etc. The bylaws, partnership agreement, operating
agreement, regulations or other analogous constitutional documents of each Loan
Party certified by its Secretary or an Assistant Secretary (or equivalent
officer or representative);

         (e) Governmental Certificates. Certificates of appropriate officials
as to the existence and good standing of each Loan Party in its jurisdiction of
incorporation, formation or organization and in all jurisdictions in which such
Loan Party is qualified or is required to qualify to do business as a foreign
entity, each such certificate to be dated as of a Current Date;

         (f) Notes. The Notes duly completed and executed by the Borrower (one
payable to the order of each Lender with respect to each of its Commitments);

         (g) Mortgages. As required by Section 5.4, each of the Loan Parties
shall execute Mortgages in favor of the Administrative Agent for the benefit of
the Lenders covering all real property owned by such Loan Party, and with
respect to each tract of real property owned by such Loan Party, except as may
not be required pursuant to Section 5.4, shall provide to the Administrative
Agent a mortgagee policy of title insurance insuring the Administrative Agent's
first priority Lien status created by each such Mortgage, a current survey
certified to the Administrative Agent and the Lenders, an appraisal complying
with all applicable regulatory requirements and an environmental survey
acceptable to the Administrative Agent;

         (h) Security Agreements and Other Security Documents. Security
Agreements and other Security Documents executed by each of the Loan Parties
pertaining to the Collateral owned by such Loan Party or in which such Loan
Party has rights sufficient to create a Lien (one such Security Agreement
executed by each such Loan Party) together with all related financing
statements and other filings, consents to collateral assignments from all
parties to all Material Contracts included as part of the Collateral in form
and substance acceptable to the Administrative Agent, delivery of all pledged
Capital Stock and instruments constituting Collateral, together with
appropriate stock or unit powers and endorsements thereto and, with respect to
each existing lease of real Property by any Loan Party, waivers of landlord's
Liens from each lessor and other agreements from such lessor and its lenders
necessary or appropriate to ensure Administrative Agent's perfected, first
priority Lien on the Collateral or Property affected thereby, the
Administrative Agent's access to such Collateral or Property and the right of
the Administrative Agent, the Lenders or their designee to succeed to the
rights of such Loan Party that is the lessee under the lease, in each case in
form and substance reasonably satisfactory to the Administrative Agent; and all
Liens in favor of the Administrative

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Agent securing the payment or performance of the Obligations shall have been
created and perfected with respect to all Collateral and shall constitute
valid, perfected first priority Liens (subject only to Permitted Liens which
are expressly permitted to have equal or greater priority in accordance with
this Agreement);

         (i) Insurance Certificates and Policies. Certificates evidencing all
insurance policies required by this Agreement and the other Loan Documents and,
if requested by the Administrative Agent, copies of all such insurance
policies;

         (j) Lien Searches. Lien searches in the name of each Loan Party (and
in all names under which any of them has done business within the last five
years) in each jurisdiction where such Loan Party maintains an office or has
Property, showing no financing statements or other Lien instruments of record
affecting the Collateral except for Permitted Liens;

         (k) Supply Agreement. Amendment No. 4 to the Supply Agreement shall
have been executed and delivered by all parties thereto and shall, subject to
the terms and conditions thereof, obligate the Borrower and the Operating
Subsidiaries to purchase at least $167,000,000 worth of Nortel Networks Goods
and Services, and the Administrative Agent shall have received a photocopy of
such amendment the Supply Agreement as so executed and delivered, certified by
a Responsible Officer of the Borrower as being a true and correct copy of such
document as of the Closing Date;

         (l) Holdings Public Offering and Holdings Senior Notes Issuance. The
Holdings Public Offering shall have been completed and the Holdings Senior
Notes shall have been issued and, in connection therewith, not less than
$210,000,000 of the net cash proceeds thereof shall have been received by
Holdings and contributed by Holdings as equity to the capital of the Borrower,
all to the reasonable satisfaction of the Administrative Agent, and, as a
result thereof and as a result of any other contributions to the equity capital
of Holdings and the Borrower prior to the Closing Date, the total contributed
equity capital of the Borrower as of the Closing Date shall not be less than
$250,000,000;

         (m) Payment of Interest, Fees and Expenses. The Borrower shall have
paid in full to the Administrative Agent (i) all interest accrued and unpaid
with respect to the Original Loans, (ii) all fees accrued and unpaid with
respect to the Original Credit Agreement and/or any commitment thereunder,
(iii) all fees due on or before the Closing Date as specified in this Agreement
or in the Administrative Agent's Letter and (iv) all fees, costs and expenses
of or incurred by the Administrative Agent and/or its counsel to the extent
billed on or before the Closing Date and payable pursuant to the Original
Credit Agreement or this Agreement;

         (n) Compliance with Laws. As of the Closing Date, the Borrower and the
other Loan Parties shall have complied in all material respects with all
Governmental Requirements necessary to consummate the transactions contemplated
by this Agreement and the other Loan Documents;

         (o) No Prohibitions. No Governmental Requirement shall prohibit the
consummation of the transactions contemplated by this Agreement or any other
Loan Document, and no order, judgment or decree of any Governmental Authority
or arbitrator shall, and no litigation or other

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proceeding shall be pending or, to the any Loan Party's knowledge, threatened
which would, enjoin, prohibit, restrain or otherwise adversely affect in any
material manner the consummation of the transactions contemplated by this
Agreement and the other Loan Documents or otherwise have a Material Adverse
Effect;

         (p) Financial Statements. Copies of each of the financial statements
referred to in Section 7.2;

         (q) Opinions of Counsel. Favorable legal opinions of counsel for the
Loan Parties, in form and substance and issued by law firms satisfactory to the
Administrative Agent, with respect to the Loan Parties and with respect to the
Loan Documents, and a favorable legal opinion of regulatory counsel to the Loan
Parties in form and substance satisfactory to the Administrative Agent;

         (r) Legal Matters and Loan Documents. All matters of a legal nature
relating to the Loan Parties and the Loan Documents shall be reasonably
satisfactory to the Administrative Agent and its counsel, and the
Administrative Agent shall have received all such other agreements, documents
and instruments, each in form and substance and executed and delivered by all
parties, as the Administrative Agent may have reasonably requested to receive;

         (s) Business Plan. A copy of the Business Plan in form and substance
satisfactory to the Administrative Agent;

         (t) Material Contracts. A true and correct and fully-executed copy of
each of the Material Contracts in existence as of the Closing Date, including,
without limitation, the Sprint Agreements and the Consents and Agreements (each
of which must be in existence as of the Closing Date) in form and substance
satisfactory to the Administrative Agent;

         (u) Permits. Copies of all PCS Licenses and all other material Permits
affecting each Loan Party or necessary in connection with the construction or
operation of the Service Area Network or in connection with its businesses or
any of the Properties owned or leased by it or its businesses to be conducted
and Properties to be owned or leased as contemplated by the Sprint Agreements
and the Business Plan, and evidence satisfactory to the Administrative Agent
that each Loan Party is able to conduct its businesses conducted and to be
conducted as contemplated by the Sprint Agreements and the Business Plan with
the use of such PCS Licenses and Permits in full force and effect; and the
Administrative Agent shall be satisfied that (i) the Borrower and the Operating
Subsidiaries have the exclusive, unrestricted right to use each of such PCS
Licenses and Permits, as applicable, pursuant to license agreements or other
agreements, documents or instruments in form and substance reasonably
satisfactory to the Administrative Agent and (ii) each of Sprint PCS, the
Borrower and the Operating Subsidiaries has complied with all initial and
on-going conditions of the issuance and use of all such PCS Licenses and
Permits and all other terms and provisions thereof; without limiting the
generality of the foregoing, the Administrative Agent shall have received (A)
copies of all Permits evidencing that the Borrower and the Operating
Subsidiaries hold all Permits necessary to construct and operate the Service
Area Network, other than the PCS Licenses for the Service Area held by Sprint
PCS under which the Borrower and the Operating Subsidiaries

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will operate pursuant to the Sprint Agreements, and (B) evidence satisfactory
to the Administrative Agent that (1) Sprint PCS holds all PCS Licenses for the
Service Area, (2) the Borrower and the Operating Subsidiaries hold all
necessary or appropriate Permits from any state public utility commission, (3)
all such PCS Licenses and Permits referred to in clauses (1) and (2) preceding
have been duly issued by the FCC and the appropriate state public utility
commission, respectively, and (4) the Borrower and the Operating Subsidiaries,
and the Administrative Agent as the collateral assignee from the Borrower and
the Operating Subsidiaries, have the exclusive, unrestricted right to use all
such PCS Licenses and Permits referred to in clauses (1) and (2) preceding
pursuant to the Sprint Agreements and such other agreements as have been
approved by the Administrative Agent;

         (v) Waivers and Consents. To the extent not referred to in clause (h)
preceding, copies of all material waivers and consents necessary for the
execution, delivery and performance by each Loan Party of the Loan Documents to
which it is a party, including, without limitation, any waivers and consents in
connection with the Supply Agreement as the Administrative Agent may require
and the grant of a security interest in each Material Contract of each Loan
Party, which waivers and consents shall be certified by a Responsible Officer
of the Borrower (or other applicable Loan Party) as true and correct copies of
such consents as of the Closing Date;

         (w) Regulatory Approvals. Evidence satisfactory to the Administrative
Agent that all filings, consents or approvals with or of Governmental
Authorities necessary to consummate the transactions contemplated by the Loan
Documents have been made and obtained, as applicable;

         (x) No Material Adverse Change. As of the Closing Date, (i) no
material adverse change shall have occurred with respect to the financial
condition, results of operations, businesses, operations, capitalization,
indebtedness, liabilities, obligations, profitability or prospects or
Properties or of the general affairs or management of the Borrower and its
Subsidiaries, taken as a whole, or of the Borrower, in each case since
September 30, 1999, (ii) no disruption or adverse change in the capital markets
generally or in the market for loan syndications in particular shall have
occurred since September 30, 1999, which disruption or adverse change is deemed
material in the judgment of the Administrative Agent, and (iii) the
Administrative Agent shall be satisfied that the financial performance of the
Borrower and its Subsidiaries and of the Borrower to the Closing Date is not
materially different from the financial projections for such Person(s) through
the Closing Date that were previously submitted to the Administrative Agent;

         (y) Form U-1. If requested by the Administrative Agent, a Form U-1
relating to any margin stock which directly or indirectly secures the
Obligations or any part thereof;

         (z) Management and Management Agreements. The Borrower shall have
hired and retained as employees an experienced telecom management team
reasonably satisfactory to the Administrative Agent and the Required Lender,
which management team shall include, at a minimum, a chief executive officer,
chief financial officer, chief operating officer and chief technology officer,
each of whom shall have entered into an employment agreement with the Borrower
providing for an employment term of not less than two years and appropriate
non- competition and non-disclosure agreements, each of which employment
agreements shall be in form and substance reasonably satisfactory to the
Administrative Agent;

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         (aa) Solvency Certificate. A certificate from Holdings and the
Borrower certifying that each of the Loan Parties is Solvent, together with
contribution agreements between and among each of the Loan Parties other than
the Borrower as the Administrative Agent may reasonably require; and

         (bb) Reorganization Transactions. Each of the Reorganization
Transactions shall have been consummated in accordance with the terms and
provisions of the agreements and documents governing such transactions, and
true and correct copies of such agreements and documents shall have been
delivered to the Administrative Agent.

The Borrower shall deliver, or cause to be delivered, to the Administrative
Agent sufficient counterparts of each agreement, document or instrument to be
received by the Administrative Agent under this Section 6. 1 to permit the
Administrative Agent to distribute a copy of the same to each of the Lenders.
After the request of the Borrower, the Administrative Agent shall inform the
Borrower in writing as to the status of satisfaction of the conditions
precedent set forth in this Section 6.1.

         Section 6.2 All Extensions of Credit. The obligation of each Lender to
make any Loan (including the initial Loan) under this Agreement is subject to
the continued satisfaction of each of the conditions precedent set forth in
Section 6.1 and each of the following additional conditions precedent:

         (a) No Default or Material Adverse Effect. No Default or Material
Adverse Effect shall have occurred and be continuing, or would result from such
Loan;

         (b) Representations and Warranties. All of the representations and
warranties of the Loan Parties contained in this Agreement and in the other
Loan Documents shall be true and correct on and as of the date of such Loan
with the same force and effect as if such representations and warranties had
been made on and as of such date unless they relate solely to an earlier date;

         (c) Ratio of Total Debt to Contributed Capital. After giving effect to
the requested Loan, the ratio of Total Debt of the Borrower and its
Consolidated Subsidiaries to Contributed Capital of the Borrower is less than
or equal to 1.50 to 1.00;

         (d) Permitted Third-Party Expenses Borrowing Base. After giving effect
to the requested Loan, the aggregate amount of proceeds of the Loans (including
the Original Loans) used to pay Permitted Third-Party Expenses shall not exceed
the Permitted Third-Party Expenses Borrowing Base;

         (e) Use of Proceeds. The Borrower shall have certified to the
Administrative Agent that all proceeds of the Loans then being made by the
Lenders are, concurrently with the making of such Loans, being used by the
Borrower for the purposes specified in Section 2.10, and the Borrower shall
have delivered to the Administrative Agent such further evidence thereof (if
any) as the Administrative Agent may reasonably request;

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         (f) Third-Party Expenses Borrowing Base Report. The Administrative
Agent shall have received a current Permitted Third-Party Expenses Borrowing
Base Report dated as of the date of the Notice of Borrowing;

         (g) Supply Agreement. The Supply Agreement shall not have been
terminated by the Borrower or any other Loan Party and shall remain in full
force and effect;

         (h) Full Disclosure. Neither the Borrower nor any other Loan Party has
failed to disclose to the Administrative Agent or any Lender any material fact
with respect to the Service Area Network or their respective financial
conditions (including any contingent liabilities) or results of operations, or
has failed to disclose any information the absence of which makes any
information previously disclosed to the Administrative Agent or any Lender
materially misleading; and

         (i) Additional Documentation. The Administrative Agent shall have
received such additional approvals, agreements, documents and instruments as
the Administrative Agent may reasonably request.

Each notice of borrowing by the Borrower hereunder shall constitute a
representation and warranty by the Borrower that the conditions precedent set
forth in this Section 6.2 have been satisfied (both as of the date of such
notice and, unless the Borrower otherwise notifies the Administrative Agent
prior to the date of such borrowing, as of the date of such borrowing).

         Section 6.3 Closing Certificates. The Borrower shall, concurrently
with the Closing Date (with respect to the conditions precedent set forth in
Section 6.1), and concurrently with the date of the making of each other Loan,
execute and deliver to the Administrative Agent a certificate in form and
substance satisfactory to the Administrative Agent certifying as to the
satisfaction of each of the conditions precedent set forth in this Article 6
which are required to be satisfied on or before such date (without regard to
whether such matters are, in fact, satisfactory to the Administrative Agent to
the extent that such satisfaction is required hereunder).

                                   ARTICLE 7

                         Representations and Warranties

         Each of the Borrower, Holdings and each Operating Subsidiary hereby
represents and warrants to the Administrative Agent and the Lenders that the
following statements are and, after giving effect to the funding of the initial
Loans on the Closing Date and continuing thereafter as long as the Obligations
or any part thereof are outstanding or any Lender has any Commitment hereunder,
will be true, correct and complete:

         Section 7.1 Existence, etc. Each of the Loan Parties (a) is a
corporation, partnership, limited liability company or other entity (as
described in the Loan Documents) duly organized, validly existing and (if and
to the extent that the concept of good standing is applicable to the type of
entity in question) in good standing under the laws of the jurisdiction of its
incorporation, formation or organization, (b) has all requisite power and
authority to own its Properties and carry

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on its business as now conducted, and (c) is qualified to do business in all
jurisdictions in which the nature of its business makes such qualification
necessary and where failure to so qualify would have a Material Adverse Effect.
Each of the Loan Parties has the power and authority and legal right to
execute, deliver and perform its obligations under the Loan Documents and the
Sprint Agreements to which it is or may become a party.

         Section 7.2 Financial Statements.

         (a) The Borrower has delivered to the Administrative Agent and the
Lenders (i) an unaudited balance sheet of Holdings and its Consolidated
Subsidiaries (including, without limitation, the Borrower), together with
consolidated schedules, as of and for the nine-month period ended September 30,
1999, and (ii) an unaudited pro forma balance sheet of Holdings and its
Consolidated Subsidiaries (including, without limitation, the Borrower),
together with consolidating schedules, dated as of January 31, 2000, which
gives effect to the initial Loans made on the Closing Date and the other
transactions that have occurred on or before the Closing Date (including,
without limitation, the Reorganization Transactions, the Holdings Public
Offering, the issuance of the Holdings Senior Notes, if applicable, and the
capital contributions to Holdings and the Borrower). Such financial statements,
as well as all other financial statements to be delivered to the Administrative
Agent in accordance with this Agreement, are or will be when delivered (as
applicable) true and correct, have been or will be (as applicable) prepared in
accordance with GAAP and fairly and accurately present or will fairly and
accurately present (as applicable), on a consolidated and consolidating basis
(as applicable), the financial condition of Holdings and its Consolidated
Subsidiaries (including without limitation, the Borrower) as of such dates and
the results of operations for the respective periods indicated therein. There
has not been, as of the Closing Date, any material adverse change in the
financial condition, results of operations, businesses, operations or
Properties of Holdings and its Subsidiaries, taken as a whole, the Borrower and
its Subsidiaries, taken as a whole, or of the Borrower on an individual basis,
since September 30, 1999 or December 31, 1999.

         (b) The Business Plan (including, without limitation, the financial
projections contained therein) represents, as of the Closing Date, the good
faith estimate of the Borrower and its senior management concerning the
probable financial condition and performance of the Borrower and its
Subsidiaries for the time period covered thereunder based upon the assumptions
believed to be reasonable at the time made.

         Section 7.3 Corporate Action; No Breach. The execution, delivery and
performance by each of the Loan Parties of the Loan Documents and the Sprint
Agreements to which it is or may become a party and compliance with the terms
and provisions hereof and thereof have been duly authorized by all requisite
entity action and do not and will not (a) violate or conflict with, or result
in a breach of, or require any consent under (i) the certificate of
incorporation, articles of incorporation, certificate of formation, certificate
of organization, partnership agreement, regulations, bylaws or other
constitutional documents of such Loan Party, (ii) any Governmental Requirement
(including, without limitation, the Communications Act, any rule or regulation
of the FCC or any rule or regulation of any state public utility commission) or
any order, writ, injunction or decree of any Governmental Authority or
arbitrator, or (iii) any material agreement, document or instrument

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to which any Loan Party is a party or by which any Loan Party or any of its
Property is bound or subject, or (b) constitute a default under any such
material agreement, document or instrument, or result in the creation or
imposition of any Lien (except a Lien in favor of the Administrative Agent for
and on behalf of the Lenders under the Security Documents as provided in
Article 5) upon any of the revenues or Property of any Loan Party.

         Section 7.4 Operation of Business; Licenses. Each of the Loan Parties
(a) possesses all material Permits, franchises, licenses and authorizations
necessary or appropriate to conduct its businesses substantially as now
conducted and as to be conducted as contemplated by the Business Plan, and (b)
has complied with all initial and on-going conditions to the issuance and use
of all such Permits, franchises, licenses and authorizations, except where
failure to comply could not reasonably be expected to have a Material Adverse
Effect. None of the Loan Parties is in violation of any such material Permits,
franchises, licenses or authorizations which could be expected to result in any
termination or cessation thereof. All of the PCS Licenses and all of the
Permits of the Loan Parties issued by any state public utility commission, and
all other material Permits, franchises, licenses and authorizations required by
any Governmental Requirement (including, without limitation, the Communications
Act, any rule or regulation of the FCC or any rule or regulation of any state
public utility commission) or issued by any Governmental Authority as of the
Closing Date, are summarized by category or type, as relevant to the operation
of the Loan Parties on Schedule 7.4 as to each Loan Party separately. Sprint
PCS holds all PCS Licenses, and the Borrower and the Operating Subsidiaries
hold all Permits of any state public utility commission, necessary to operate a
PCS system in each of the BTAs set forth on Schedule 1.1(c). Such PCS Licenses
and Permits are as set forth on Schedule 7.4, have been duly issued by the FCC
and the appropriate state public utility commission (as applicable) and are in
full force and effect, and all provisions of such PCS Licenses and Permits have
been complied with in all material respects. No PCS License or Permit for any
BTA set forth on Schedule 1.1(c) is subject to any pending or, to the knowledge
of any Loan Party, threatened revocation or termination proceeding or action.

         Section 7.5 Intellectual Property. The Intellectual Property owned or
used by each of the Loan Parties in the operation of their respective
businesses are set forth on Schedule 7.5. Each of the Loan Parties owns or
possesses (or will be licensed or have the full right to use) all Intellectual
Property which is necessary or appropriate for the operation of their
respective businesses as presently conducted and as proposed to be conducted,
without any known conflict with the rights of others. The consummation of the
transactions contemplated by this Agreement and the other Loan Documents will
not materially alter or impair, individually or in the aggregate, any of such
rights of the Loan Parties. No product or service of any of the Loan Parties
infringes upon any Intellectual Property of any other Person, and no claim or
litigation is pending or, to the knowledge of any Loan Party, threatened
against any Loan Party contesting its right to sell or otherwise use any
product or material or service which could reasonably be expected to have a
Material Adverse Effect. There is no violation by any Loan Party of any right
of any such other Person with respect to any material Intellectual Property
owned or used by any such other Person.

         Section 7.6 Litigation and Judgments. Each material action, suit,
investigation or proceeding before or by any Governmental Authority or
arbitrator pending or, to the knowledge of any Loan Party, threatened against
or affecting any Loan Party, or that relates to any of the Loan

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Documents as of the Closing Date, is disclosed on Schedule 7.6. None of such
actions, suits, investigations or proceedings could, if adversely determined,
reasonably be expected to have a Material Adverse Effect. Except as may be
disclosed on Schedule 7.6, as of the Closing Date, there are no outstanding
judgments against any Loan Party. No Loan Party has received any opinion or
memorandum or legal advice in writing from legal counsel to the effect that it
is exposed to any liability or disadvantage that could reasonably be expected
to have a Material Adverse Effect.

         Section 7.7 Rights in Properties; Liens. Except as disclosed on
Schedule 7.7, none of the Loan Parties owns any right, title or interest in any
real Property. Each of the Borrower and its Subsidiaries has good and
marketable title to or, with respect to leasehold interests, valid leasehold
interests in all of its material Properties and assets, real and personal,
including the material Properties, assets and leasehold interests reflected in
the financial statements described in Section 7.2(a), except where failure to
have good and marketable title or valid leasehold interests could not
reasonably be expected to have a Material Adverse Effect, and none of the
Properties or leasehold interests of any of the Loan Parties is subject to any
Lien, except Permitted Liens. The Borrower or an Operating Subsidiary of the
Borrower owns all existing Operating Assets. No Loan Party has granted or
voluntarily allowed or permitted to exist any Lien to or in favor of any Person
(other than the Administrative Agent for and on behalf of the Lenders as
security for the Obligations) which attaches or relates to any of the
Collateral and the Liens on the Collateral in favor of the Administrative Agent
are perfected, first priority Liens subject only to Permitted Liens which are
expressly permitted to be equal or prior to the Liens of the Administrative
Agent in the definition of the term "Permitted Liens".

         Section 7.8 Enforceability. The Loan Documents have been duly and
validly executed and delivered by each of the Loan Parties that is a party
thereto, and such Loan Documents constitute the legal, valid and binding
obligations of such Persons, enforceable against each such Person in accordance
with their respective terms, except as limited by bankruptcy, insolvency or
other laws of general application relating to the enforcement of creditors'
rights and general principles of equity.

         Section 7.9 Approvals. No authorization, approval or consent of, and
no filing or registration with or notice to, any Governmental Authority
(including the FCC) or other Person is or will be necessary for the execution,
delivery or performance by any Loan Party of any of the Loan Documents or any
of the Sprint Agreements to which it is or will be a party or for the validity
or enforceability thereof, except for such consents, approvals and filings as
have been validly obtained or made and are in full force and effect. The
consummation of the transactions contemplated by the Loan Documents and the
Sprint Agreements does not require the consent or approval of any other Person,
except such consents and approvals (a) as have been validly obtained and are in
full force and effect or (b) as to which the failure to obtain is not,
individually or in the aggregate, material. None of the Loan Parties has failed
to obtain any material consent, approval, license, Permit, franchise or other
authorization of any Governmental Authority (including the FCC) necessary for
the ownership or use of any of its Properties, conduct of its business and
performance of the Business Plan.

         Section 7.10 Debt. As of the Closing Date, none of the Loan Parties
has any Debt other than (a) the Obligations, and (b) the Debt disclosed on
Schedule 7.10 hereto.

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         Section 7.11 Taxes. Each of the Loan Parties has filed (a) all tax
returns (federal, state and local) and reports required to be filed, including,
without limitation, all income, franchise, employment, Property and sales tax
returns, and (b) all other material tax returns and reports required to be
filed except where failure to file could not reasonably be expected to have a
Material Adverse Effect, and has paid all federal and other material taxes
(shown on such returns or reports to be due and payable), assessments, fees and
other governmental charges levied or imposed upon it or its Properties, income
or assets otherwise due and payable before they become delinquent, except those
which are being contested in good faith by appropriate proceedings and for
which adequate reserves have been provided in accordance with GAAP and no
notice of Lien has been filed or recorded. There is no proposed tax assessment
against any Loan Party which could, if the assessment were made, reasonably be
expected to have a Material Adverse Effect.

         Section 7.12 Margin Securities. None of the Loan Parties is engaged
principally, or as one of its important activities, in the business of
extending credit for the purpose of purchasing or carrying margin stock (within
the meaning of Regulations T, U or X of the Board of Governors of the Federal
Reserve System), and no part of the proceeds of any Loan will be used to
purchase or carry any margin stock or to extend credit to others for the
purpose of purchasing or carrying margin stock.

         Section 7.13 ERISA. None of the Loan Parties or any ERISA Affiliate
maintains or contributes to, or has any obligation under, any Pension Plan
other than the Pension Plans identified on Schedule 7.13. Each Plan of the Loan
Parties is in compliance in all material respects with all applicable
provisions of ERISA and the Code. Neither a Reportable Event nor a Prohibited
Transaction has occurred within the last 60 months with respect to any Plan
that could reasonably be expected have a Material Adverse Effect. No notice of
intent to terminate a Pension Plan has been filed, nor has any Pension Plan
been terminated. No circumstances exist which constitute grounds entitling the
PBGC to institute proceedings to terminate, or appoint a trustee to administer,
a Pension Plan, nor has the PBGC instituted any such proceedings. Neither any
Loan Party nor any ERISA Affiliate has completely or partially withdrawn from a
Multiemployer Plan. Each of the Loan Parties and each ERISA Affiliate have met
their minimum funding requirements under ERISA and the Code or with respect to
all of their Pension Plans subject to such requirements, and, as of the Closing
Date except as specified on Schedule 7.13, the present value of all vested
benefits under each funded Plan (exclusive of any Multiemployer Plan) does not
and will not exceed the fair market value of all such Plan assets allocable to
such benefits, as determined on the most recent valuation date of such Plan and
in accordance with ERISA. Neither any Loan Party nor any ERISA Affiliate has
incurred any liability to the PBGC under ERISA. No litigation is pending or, to
any Loan Party's knowledge, threatened concerning or involving any Plan that
could reasonably be expected to have a Material Adverse Effect. There are no
unfunded or unreserved liabilities (on either a going- concern basis or a
wind-up basis) relating to any Plan that could, individually or in the
aggregate, have a Material Adverse Effect if the Borrower were required to fund
or reserve such liability in full. As of the Closing Date, no funding waivers
have been or will have been requested or granted under Section 412 of the Code
with respect to any Plan. No unfunded or unreserved liability for benefits
under any Plan or Plans (exclusive of any Multiemployer Plans) exceeds
$500,000, with respect to any such Plan, or $1,000,000 with respect to all such
Plans, in the aggregate as of the Closing Date, on either a going-concern basis
or a wind-up basis.

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         Section 7.14 Disclosure. No written statement, information, report,
representation or warranty made by any Loan Party in any Loan Document or
furnished to the Administrative Agent or any Lender by or on behalf of any Loan
Party in connection with the Loan Documents or any transaction contemplated
hereby or thereby contains any untrue statement of a material fact or omits to
state any material fact necessary to make the statements herein or therein, in
light of the circumstances in which made, not misleading. There is no fact
known to any Loan Party which has had a Material Adverse Effect, and there is
no fact known to any Loan Party which might in the future have a Material
Adverse Effect except as may have been disclosed in writing to the
Administrative Agent.

         Section 7.15 Loan Parties; Capitalization. The Borrower is a
Wholly-Owned Subsidiary of Holdings and all issued and outstanding Capital
Stock of the Borrower is owned, beneficially and of record, by Holdings. Except
for the issued and outstanding Capital Stock of Alamosa Texas which is owned,
beneficially and of record, by Alamosa Texas GP as of the Closing Date (as
specified in Schedule 7.15), Alamosa Texas is a Wholly-Owned Subsidiary of the
Borrower and all issued and outstanding Capital Stock of Alamosa Texas is
owned, beneficially and of record, by the Borrower. Except for the issued and
outstanding Capital Stock of Alamosa Wisconsin which is owned, beneficially and
of record, by Alamosa Wisconsin GP and certain Wisconsin telephone companies as
of the Closing Date (as specified in Schedule 7.15), Alamosa Wisconsin is a
Wholly- Owned Subsidiary of the Borrower and all issued and outstanding Capital
Stock of Alamosa Wisconsin is owned, beneficially and of record, by the
Borrower. Each of Alamosa Texas GP and Alamosa Wisconsin GP is a Wholly-Owned
Subsidiary of the Borrower and all issued and outstanding Capital Stock of each
of Alamosa Texas GP and Alamosa Wisconsin GP is owned, beneficially and of
record, by the Borrower. Schedule 7.15 attached hereto contains, as of the
Closing Date, complete and accurate information regarding (a) the identities of
each of the Subsidiaries of Holdings and the Borrower, (b) the number of issued
and outstanding shares (or other units) of each class of Capital Stock issued
by each of the Loan Parties and the identities of, and number and percentage of
each of such shares (or other units) held by, (i) with respect to the Capital
Stock of Holdings, the Former Members and (ii) with respect to the Capital
Stock of each of the other Loan Parties, the owner(s) (both of record and
beneficially) of such Capital Stock, and (c) the jurisdiction of incorporation
or other organization of each of the Loan Parties.

         Section 7.16 Compliance with Laws. None of the Loan Parties is in
violation of any Governmental Requirement (including, without limitation, the
Communications Act, any rule or regulation of the FCC or any rule or regulation
of any state public utility commission), except for instances of non-compliance
that could not, individually or in the aggregate, reasonably be expected to
have a Material Adverse Effect.

         Section 7.17 Investment Company Act. None of the Loan Parties is an
"investment company" within the meaning of the Investment Company Act of 1940,
as amended.

         Section 7.18 Public Utility Holding Company Act. None of the Loan
Parties is a "holding company" or a "subsidiary company" of a "holding company"
or an "affiliate" of a "holding company" or a "public utility" within the
meaning of the Public Utility Holding Company Act of 1935, as amended.

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Section 7.19 Environmental Matters.

         (a) Except for instances of noncompliance with or exceptions to any of
the following representations and warranties that could not have, individually
or in the aggregate, a Material Adverse Effect:

                  (i) Each of the Loan Parties and all of their respective
         Properties and operations are in full compliance with all
         Environmental Laws. No Loan Party is aware of, and no Loan Party has
         received written notice of, any past, present or future conditions,
         events, activities, practices or incidents which may interfere with or
         prevent the compliance or continued compliance by the Loan Parties
         with all Environmental Laws;

                  (ii) Each of the Loan Parties has obtained all Permits that
         are required under applicable Environmental Laws, and all such Permits
         are in good standing and all such Persons are in compliance with all
         of the terms and conditions thereof;

                  (iii) No Hazardous Materials exist on, about or within or
         have been (to the knowledge of any Loan Party) or are being used,
         generated, stored, transported, disposed of on or Released from any of
         the Properties of any of the Loan Parties except in compliance with
         applicable Environmental Laws. The use which each of the Loan Parties
         make and intend to make of its Properties will not result in the use,
         generation, storage, transportation, accumulation, disposal or Release
         of any Hazardous Material on, in or from any of their currently owned
         Properties except in compliance with applicable Environmental Laws;

                  (iv) There are no conditions or circumstances associated with
         the currently owned or leased Properties or operations of any of the
         Loan Parties that could reasonably be expected to give rise to any
         Environmental Liabilities or claims resulting in any Environmental
         Liabilities;

                  (v) None of the Loan Parties and none of its currently or
         previously owned or leased Properties or operations is subject to any
         outstanding or, to the knowledge of any Loan Party, threatened order
         from or agreement with any Governmental Authority or other Person or
         subject to any judicial or administrative proceeding with respect to
         (A) any failure to comply with Environmental Laws, (B) any Remedial
         Action, or (C) any Environmental Liabilities;

                  (vi) None of the Loan Parties is subject to, or has received
         written notice of any claim from any Person alleging that it is or
         will be subject to, any Environmental Liabilities;

                  (vii) None of the Properties of any of the Loan Parties is a
         treatment facility (except for the recycling of Hazardous Materials
         generated on-site and the treatment of liquid wastes subject to the
         Clean Water Act or other applicable Environmental Law for temporary
         storage of Hazardous Materials generated on-site prior to their
         disposal off-site) or disposal facility requiring a permit under the
         Resource Conservation and Recovery Act, 42 U.S.C. ss.

CREDIT AGREEMENT - Page 67

<PAGE>   75

         6901 et seq., regulations thereunder or any comparable provision of
         state law. Each of the Loan Parties is in compliance with all
         applicable financial responsibility requirements of all Environmental
         Laws; and

                  (viii) None of the Loan Parties has failed to file any notice
         required under applicable Environmental Law reporting a Release.

         (b) No Lien arising under any Environmental Law that could have,
individually or in the aggregate, a Material Adverse Effect has attached to any
Property or revenues of any of the Loan Parties.

         Section 7.20 Year 2000 Compliance. The Borrower has (a) initiated a
review and assessment of all areas within the businesses and operations
(including those affected by suppliers and vendors) of the Loan Parties that
could reasonably be expected to be relevant to whether the Loan Parties are
Year 2000 Compliant, (b) developed a plan and timeline for ensuring that the
Loan Parties are Year 2000 Compliant on a timely basis, and (c) to date,
implemented that plan in accordance with that timetable. Based upon the
foregoing, the Borrower believes that each of the Loan Parties is Year 2000
Compliant as of the Closing Date except to the extent as may be described in
Schedule 8.15 and except for instances of noncompliance that could not,
individually or in the aggregate, reasonably be expected to have a Material
Adverse Effect.

         Section 7.21 Labor Disputes and Acts of God. Neither the business nor
the Properties of any of the Loan Parties are affected by any fire, explosion,
accident, strike, lockout or other labor dispute, drought, storm, hail,
earthquake, embargo, act of God or of the public enemy or other casualty
(whether or not covered by insurance) that is having or could reasonably be
expected to have a Material Adverse Effect.

         Section 7.22 Material Contracts. Attached hereto as Schedule 7.22 is a
complete list, as of the Closing Date, of all Material Contracts of each of the
Loan Parties, other than the Loan Documents, which list sets forth each of the
parties to each of the Material Contracts. All of the Material Contracts are in
full force and effect and none of the Loan Parties is in default under any
Material Contract and, to the knowledge of the Loan Parties after due inquiry,
no other Person that is a party thereto is in default under any of the Material
Contracts. Each of the Loan Parties is in compliance with the terms and
provisions of the Sprint Agreements. None of the Material Contracts prohibits
the transactions contemplated under the Loan Documents. Except as may be
provided on Schedule 7.22, (a) each of the Material Contracts has been
transferred or assigned to, or is currently in the name of, a Loan Party and
(b) subject to the provisions of the Sprint Agreements, as the same may be
modified or superseded by the Consents and Agreements, each of the Material
Contracts is assignable to the Administrative Agent as collateral and is
assignable by the Administrative Agent to a transferee if an Event of Default
were to occur. The Borrower has delivered to the Administrative Agent a
complete and current copy of each Material Contract of any Loan Party (other
than purchase orders entered into in the ordinary course of business) existing
on the Closing Date.

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         Section 7.23 Bank Accounts. As of the Closing Date, Schedule 7.23 sets
forth the account numbers and location of all bank accounts (including lock box
and special deposit accounts) of each of the Loan Parties.

         Section 7.24 Outstanding Securities. As of the Closing Date, all
outstanding securities (as defined in the Securities Act of 1933, as amended,
or any successor thereto, and the rules and regulations of the Securities and
Exchange Commission thereunder) of the Loan Parties have been offered, issued,
sold and delivered in compliance with all applicable Governmental Requirements.

         Section 7.25 Solvency. Each of the Loan Parties, as a separate entity,
is Solvent, both before and after giving effect to the Loans.

         Section 7.26 Employee Matters. Except as set forth on Schedule 7.26,
as of the Closing Date (a) none of the Loan Parties nor any of their employees
is subject to any collective bargaining agreement, and (b) no petition for
certification or union election is pending with respect to the employees of any
Loan Party, and no union or collective bargaining unit has sought such
certification or recognition with respect to the employees of any Loan Party.
There are no strikes, slowdowns, work stoppages or controversies pending or, to
the best knowledge of the Loan Parties after due inquiry, threatened against,
any of the Loan Parties or their respective employees which could have, either
individually or in the aggregate, a Material Adverse Effect. Except as set
forth on Schedule 7.26, as of the Closing Date, none of the Loan Parties is
subject to an employment contract.

         Section 7.27 Insurance. Schedule 7.27 sets forth a complete and
accurate description of all policies of insurance that will be in effect as of
the Closing Date for the Loan Parties and their Properties. To the extent such
policies have not been replaced, no notice of cancellation has been received
for such policies and each of the Loan Parties which is the owner or holder of
each such policy is in compliance with all of the terms and conditions of such
policy.

         Section 7.28 Common Enterprise. Holdings and its Subsidiaries
(including, without limitation, the Borrower) are members of an affiliated
group with each other such Person and are collectively engaged in a common
enterprise with one another. Each of the Loan Parties expects to derive
substantial benefit (and may reasonably be expected to derive substantial
benefit), directly and indirectly, from the Loans contemplated by this
Agreement, both in its separate capacity and as a member of an affiliated and
integrated group.

         Section 7.29 Reorganization Transactions. Each of the Reorganization
Transactions has been, on or before the Closing Date, consummated in accordance
with the terms and provisions of the agreements and documents governing such
transactions, and true and correct copies of such agreements and documents have
been delivered to the Administrative Agent.

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<PAGE>   77

                                   ARTICLE 8

                             Affirmative Covenants

         Each of the Borrower, Holdings and each Operating Subsidiary hereby
covenants and agrees that, as long as the Obligations or any part thereof are
outstanding or any Lender has any Commitment hereunder, it will perform and
observe, or cause to be performed and observed, the following covenants :

         Section 8.1 Reporting Requirements. The Loan Parties will furnish (or
will cause to be furnished) to the Administrative Agent and each Lender:

         (a) Annual Financial Statements. As soon as available, and in any
event within 90 days after the end of each fiscal year of Holdings, beginning
with the fiscal year ended December 31, 1999, either a copy of the form 10-K
(including all financial statements contained therein) filed by Holdings as of
the end of and for such fiscal year then ended, together with audited
consolidating schedules for each of Holdings and its Consolidated Subsidiaries
(including, without limitation, the Borrower) with respect to the financial
statements contained therein, or a copy of the annual audit report (including
the consolidated balance sheet) of Holdings and its Consolidated Subsidiaries
(including, without limitation, the Borrower) as of the end of such year and
the related audited consolidated statements of income or operations,
shareholders' equity and cash flows for such fiscal year, together with audited
consolidating schedules for Holdings and its Consolidated Subsidiaries,
(including, without limitation, the Borrower) with respect to each of such
financial statements, in each case setting forth in comparative form the
figures for the previous fiscal year, and accompanied by the opinion of
independent certified public accountants of recognized standing reasonably
acceptable to the Administrative Agent, which opinion shall state that such
consolidated financial statements present fairly the financial position and
results of operations for the periods indicated in conformity with GAAP applied
on a basis consistent with prior years and which opinion shall not be qualified
or limited because of a restricted or limited examination by such accountant of
any material portion of such Person's records;

         (b) Quarterly Financial Statements. As soon as available, and in any
event within 45 days after the end of each of the quarters of each fiscal year
of Holdings, beginning with the fiscal quarter ending December 31, 1999, either
a copy of the form 10-Q (including all financial statements contained therein)
filed by Holdings as of the end of and for such fiscal quarter then ended,
together with consolidating schedules for each of Holdings and its Consolidated
Subsidiaries (including, without limitation, the Borrower) with respect to each
of the financial statements contained therein, or a copy of the unaudited
consolidated balance sheet of Holdings and its Consolidated Subsidiaries
(including, without limitation, the Borrower) as of the end of such quarter and
the related consolidated statements of income or operations, shareholders'
equity and cash flows and quarterly operating budgets (or such other
information comparable to operating budgets as Holdings or the Borrower
prepares for its own internal purposes) for the period commencing on the first
day and ending on the last day of such quarter, together with unaudited
consolidating schedules for Holdings and its Consolidated Subsidiaries
(including, without limitation, the Borrower) with respect to each of such
financial statements, in each case setting forth in comparative form the
information or figures

CREDIT AGREEMENT - Page 70

<PAGE>   78

for the corresponding period of the preceding fiscal year, and certified by an
appropriate Responsible Officer of Holdings as fairly presenting, in accordance
with GAAP, the financial position and the results of operations of Holdings and
its Consolidated Subsidiaries (including, without limitation, the Borrower)
(except for year-end adjustments and financial statement footnotes required by
GAAP);

         (c) Compliance Certificate. Concurrently with the delivery of each of
the financial statements referred to in Sections 8.1(a) and 8.1(b), a
Compliance Certificate of a Responsible Officer of the Borrower substantially
in the form of Exhibit D hereto, appropriately completed, stating that, to the
best of such officer's knowledge, no Default has occurred and is continuing or,
if a Default has occurred and is continuing, stating the nature thereof and the
action that has been taken and is proposed to be taken with respect thereto;

         (d) Notice of Actions, Suits or Proceedings. Promptly after the
commencement thereof, notice of all actions, suits and proceedings before any
Governmental Authority (including the FCC) or arbitrator affecting any Loan
Party, any Sprint Agreement or any PCS License or material Permit, which, if
determined adversely to any Loan Party, Sprint Spectrum or Sprint PCS, could
reasonably be expected to have a Material Adverse Effect;

         (e) Notice of Default, etc.. As soon as possible and in any event
immediately upon any Loan Party's knowledge of the occurrence of any Default, a
written notice setting forth the details of such Default and the action that
any Loan Party has taken and, if and to the extent known, proposes to take with
respect thereto;

         (f) ERISA Plan Reports. Promptly after the filing or receipt thereof,
copies of all reports, including annual reports, and notices which any Loan
Party or any of its respective ERISA Affiliates files with or receives from the
PBGC or the U.S. Department of Labor under ERISA with respect to a Pension Plan
or for which any Loan Party has any potential liability; and as soon as
possible and in any event within five days after any Loan Party knows or has
reason to know that any such Pension Plan is insolvent, or that any Reportable
Event or Prohibited Transaction has occurred with respect to any Plan or
Multiemployer Plan, or that the PBGC, or any Loan Party or any of its
respective ERISA Affiliates has instituted or will institute proceedings under
ERISA to terminate or withdraw from or reorganize any Pension Plan, a
certificate of a Responsible Officer of the Borrower setting forth the details
as to such insolvency, withdrawal, Reportable Event, Prohibited Transaction or
termination and the action that any Loan Party has taken and proposes to take
with respect thereto;

         (g) Proxy Statements, Etc. As soon as available, one copy of each (if
any) financial statement, report, notice or proxy statement sent by any Loan
Party to its stockholders or other security holders generally, one copy of each
(if any) regular, periodic or special report (including, without limitation,
reports on forms 10-K, 10-Q and 8-K), registration statement or prospectus
filed by any Loan Party with any securities exchange or the Securities and
Exchange Commission or any successor agency and one copy of each press release
or other statement made by any Loan Party to the public containing material
developments relating to its business, operations or prospects;

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<PAGE>   79

         (h) Insurance. Within 60 days prior to the end of each fiscal year of
the Borrower, a report in form and substance reasonably satisfactory to the
Administrative Agent summarizing all material insurance coverage maintained by
the Loan Parties as of the date of such report and all material insurance
coverage planned to be maintained by such Persons in the subsequent fiscal
year;

         (i) Plan Information. From time to time, as reasonably requested by
the Administrative Agent or any Lender, such books, records and other documents
relating to any Pension Plan as the Administrative Agent or any Lender shall
specify; prior to any termination, partial termination or merger of a Pension
Plan covering employees of any Loan Party or any of its ERISA Affiliates, or a
transfer of assets of a Pension Plan covering employees of any Loan Party or
any of its ERISA Affiliates, written notification thereof; promptly upon any
Loan Party's receipt thereof, a copy of any determination letter or advisory
opinion regarding any Pension Plan received from any Governmental Authority and
any amendment or modification thereto as may be necessary as a condition to
obtaining a favorable determination letter or advisory opinion; and promptly
upon the occurrence thereof, written notification of any action requested by
any Governmental Authority to be taken as a condition to any such determination
letter or advisory opinion;

         (j) Business Plan, etc. Not later than 15 days prior to the end of
each year, an update of the Business Plan in reasonable detail generally
consistent with the form and substance of the Business Plan provided to the
Administrative Agent on or before the Closing Date, which update shall reflect
the corresponding information for the prior year;

         (k) Permitted Third-Party Expenses Borrowing Base Reports. As soon as
available and in any event within 45 days after the end of each fiscal quarter,
and, in any event concurrently with the making of each Loan hereunder and from
time to time upon the request of the Administrative Agent after the occurrence
of a Default, a Permitted Third-Party Expenses Borrowing Base Report duly
completed; provided, however, no Permitted Third-Party Expenses Borrowing Base
Report shall be required to be delivered with respect to the Permitted
Third-Party Expenses Borrowing Base at any time after six months after the
termination of the later to occur of the Tranche B Commitment Termination Date
or the Tranche C Commitment Termination Date;

         (l) Management Letters. Promptly upon each receipt thereof by any Loan
Party, a copy of any management letter or other written report submitted to
such Person by independent certified public accountants with respect to the
business, condition (financial or otherwise), operations, prospects or
Properties of any such Person;

         (m) Reports to Other Creditors. Promptly after the furnishing thereof,
a copy of any financial or other material statement or report furnished by any
Loan Party to any other party pursuant to the terms of any indenture, loan,
stock purchase or credit or similar agreement and not otherwise required to be
furnished to the Administrative Agent and the Lenders pursuant to any other
clause of this Section 8.1;

         (n) Notice of Material Adverse Effect. Within three Business Days
after any Loan Party becomes aware thereof, written notice of any matter that
could reasonably be expected to have a Material Adverse Effect;

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<PAGE>   80

         (o) Environmental Assessments and Notices. Promptly after the receipt
thereof, a copy of each environmental assessment (including any analysis
relating thereto) prepared with respect to any Property of any Loan Party and
each notice sent by any Governmental Authority relating to any failure or
alleged failure to comply with any Environmental Law or any liability with
respect thereto;

         (p) Notices Under Sprint Agreements. Promptly after the receipt by any
Loan Party and promptly after the delivery by any Loan Party, a copy of each
written notice delivered under any Sprint Agreement which notice (i) relates to
an "Event of Termination" as defined in any Sprint Management Agreement, (ii)
relates to the FCC or a PCS License or is delivered in connection with Section
2.2 (Compliance with Regulatory Rules) or Section 16 of any Sprint Management
Agreement (Regulatory Compliance), (iii) relates to a dispute resolution
proceeding under Section 16 of any Sprint Management Agreement (Dispute
Resolution), (iv) relates to performance or status of completion of the
Build-out Plan, or (v) otherwise relates to matter under the Sprint Agreements
which could give rise to Material Adverse Effect;

         (q) Quarterly Performance Statistics. As soon as available and in any
event within 45 days after the end of each fiscal quarter, a summary of (i) the
number of cell sites constructed during such fiscal quarter, (ii) the total
number of Wireless Subscribers as of the end of such fiscal quarter, (iii) the
number of Wireless Subscribers acquired and terminated during such fiscal
quarter, (iv) the average monthly charges billed to Wireless Subscribers during
such fiscal quarter, (v) the average number of minutes used by Wireless
Subscribers per month during such fiscal quarter and (vi) such other
performance statistics as the Administrative Agent or any Lender may from time
to time reasonably request;

         (r) Operating Subsidiary Equity. As soon as available and in any event
within 45 days after the end of each fiscal quarter, a report identifying the
aggregate amount of all Loan proceeds contributed as equity capital to each
Operating Subsidiary or invested in, advanced to or otherwise used by each
Operating Subsidiary.

         (s) Accounts Receivable and Payable. As soon as available and in any
event within 45 days after the end of each fiscal quarter, an aged trial
balance of all then-existing Receivables and all then existing accounts payable
of each Loan Party, provided, however, that, with respect to Receivables of the
Borrower or an Operating Subsidiary collected by Sprint PCS, the Borrower may
promptly deliver to the Administrative Agent a copy of the information relating
thereto delivered by Sprint PCS to the Borrower or such Operating Subsidiary
and such delivery shall satisfy the requirements of this clause (s) relating to
such Receivables;

         (t) Accountant's Letter. On or before the Closing Date, a letter from
Holdings and the Borrower authorizing their independent public accountants to
communicate with the Administrative Agent and the Lenders and acknowledging
reliance with the Administrative Agent and the Lenders on past, present and
future financial statements; and

         (u) General Information. Promptly, such other business, financial,
corporate affairs and other similar information concerning any Loan Party
and/or any Collateral as the Administrative Agent or any Lender may from time
to time reasonably request.

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         Section 8.2 Maintenance of Existence; Conduct of Business. Each of the
Loan Parties will preserve and maintain its entity existence and all of its
leases, privileges, licenses, Permits, franchises, qualifications, Intellectual
Property, intangible Property and rights that are necessary or appropriate in
the ordinary course of its business, except to the extent that failure to
preserve or maintain the same could not reasonably be expected to have a
Material Adverse Effect. Without limiting the generality of the foregoing, each
of the Borrower and its Operating Subsidiaries (a) has entered into, or will
timely enter into, such long-distance carrier and interconnection agreements
(or agreements with third parties, such as the Sprint Agreements, which provide
such long-distance carrier and interconnection rights indirectly) as are, at
any time of determination, then necessary to the conduct of its business in
accordance with the Business Plan and (b) will conduct its business generally
in accordance with the Business Plan, in each case except to the extent that
the failure to do so could not reasonably be expected to cause a Material
Adverse Effect. Each of the Loan Parties will conduct its business in an
orderly and efficient manner in accordance with good business practices and the
Business Plan.

         Section 8.3 Maintenance of Properties and Permits. Each of the Loan
Parties will maintain, keep and preserve all of its Properties and Permits
necessary in the proper conduct of its businesses in good repair, working order
and condition (ordinary wear and tear excepted) and make all necessary repairs,
renewals and replacements and improvements thereof.

         Section 8.4 Taxes and Claims. Each of the Loan Parties will pay or
discharge before becoming delinquent (a) all taxes, levies, assessments and
governmental charges imposed on it or its income or profits or any of its
Property and (b) all lawful claims for labor, material and supplies, which, if
unpaid, might become a Lien upon any of its Property; provided, however, that
none of the Loan Parties shall be required to pay or discharge any tax, levy,
assessment or governmental charge, or claim for labor, material or supplies,
whose amount, applicability or validity is being contested in good faith by
appropriate proceedings being diligently pursued and for which adequate
reserves have been established under GAAP.

         Section 8.5        Insurance.

         (a) Each of the Loan Parties will keep insured by financially sound
and reputable insurers all Property of a character usually insured by
responsible entities engaged in the same or a similar business similarly
situated against loss or damage of the kinds and in the amounts customarily
insured against by such corporations or entities and carry such other insurance
as is usually carried by such corporations or entities, provided that in any
event each of the Loan Parties (if and to the extent that it has Properties
that are capable of being covered by the following insurance) will maintain:

                  (i) Property Insurance. Insurance against loss or damage
         covering substantially all of the tangible real and personal Property
         (including, without limitation, the Service Area Network and related
         equipment) and improvements of such Person by reason of any Peril (as
         defined below) in such amounts (subject to any deductibles as shall be
         satisfactory to the Administrative Agent) as shall be reasonable and
         customary and sufficient to avoid the insured named therein from
         becoming a co-insurer of any loss under such policy, but in any

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         event in such amounts as are reasonably available as determined by the
         Borrower's independent insurance broker reasonably acceptable to the
         Administrative Agent.

                  (ii) Automobile Liability Insurance for Bodily Injury and
         Property Damage. Insurance in respect of all vehicles (whether owned,
         hired or rented by such Person) at any time located at, or used in
         connection with, its Properties or operations against liabilities for
         bodily injury and Property damage in such amounts as are then
         customary for vehicles used in connection with similar Properties and
         businesses, but in any event to the extent required by applicable law.

                  (iii) Comprehensive General Liability Insurance. Insurance
         against claims for bodily injury, death or Property damage occurring
         on, in or about the Property (and adjoining streets, sidewalks and
         waterways) of such Person, in such amounts as are then customary for
         Property similar in use in the jurisdictions where such Properties are
         located.

                  (iv) Worker's Compensation Insurance. Worker's compensation
         insurance (including employers' liability insurance) to the extent
         required by applicable law, which may be self-insurance to the extent
         permitted by applicable law.

Without limiting the generality of the foregoing, the Borrower and its
Subsidiaries shall purchase and maintain in effect all-risk, property and
casualty insurance (including casualty insurance covering earthquake and flood
damage) covering all tangible, real and personal Property (including, without
limitation, the Service Area Network and Nortel Networks Equipment and related
equipment) and liability insurance covering the operations of the Borrower and
its Subsidiaries, in each case in such amounts (not to exceed the greater of
original cost or fair market value) and as otherwise reasonably acceptable to
the Administrative Agent and the Required Lenders. Such insurance shall be
written by financially responsible companies selected by the Borrower and
having an A.M. Best Rating of "A-" or better and being in a financial size
category of "VI" or larger, or by other companies reasonably acceptable to the
Administrative Agent. Each policy referred to in this Section 8.5 shall name
the Administrative Agent (for the benefit of itself and the other Lenders) as
loss payee (with respect to casualty insurance policies) and additional insured
(with respect to liability insurance policies) and shall provide that it will
not be canceled, amended or reduced except after not less than 30 days' prior
written notice to the Administrative Agent and shall also provide that the
interests of the Administrative Agent and the Lenders shall not be invalidated
or reduced by any act, omission or negligence of the Borrower or any of its
Subsidiaries. The Borrower will advise the Administrative Agent promptly of any
policy cancellation, reduction or amendment. For purposes hereof, the term
"Peril" shall mean, collectively, fire, lightning, flood, windstorm, hail,
explosion, riot and civil commotion, vandalism and malicious mischief, damage
from aircraft, vehicles and smoke and other perils covered by the "all-risk"
endorsement then in use in the jurisdictions where the Properties of the Loan
Parties are located.

         (b) Each of the Loan Parties will cause each Insurance Recovery (other
than any portion of an Insurance Recovery payable to a landlord to repair or
replace Property leased by the Borrower or any of its Subsidiaries) payable by
any insurance company to be deposited promptly with the Administrative Agent as
security for the Obligations if a Default has then occurred and is continuing,

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and will promptly pay all Insurance Recoveries to the Administrative Agent for
application against the Obligations if and to the extent required in accordance
with Section 2.7(a).

         (c) If a Default shall have occurred and be continuing, each of the
Loan Parties will cause all proceeds of insurance paid on account of the loss
of or damage to any Property of any Loan Party and all awards of compensation
for any Property of any Loan Party taken by condemnation or eminent domain to
be promptly paid directly to the Administrative Agent to be applied against or
held as security for the Obligations, at the election of the Administrative
Agent and the Required Lenders.

         Section 8.6 Inspection Rights. Each of the Loan Parties will permit
representatives and agents of the Administrative Agent and each Lender, during
normal business hours and upon reasonable notice to the Borrower, to examine,
copy and make extracts from its books and records, to visit and inspect its
Properties and to discuss its business, operations and financial condition with
its officers and independent certified public accountants. Each of the Loan
Parties will authorize its accountants in writing (with a copy to the
Administrative Agent) to comply with this Section 8.6. The Administrative Agent
or its representatives may, at any time and from time to time at the Borrower's
expense, conduct field exams to verify the Permitted Third-Party Expenses
Borrowing Base and for such other purposes as the Administrative Agent may
reasonably request, provided, however, that such exams shall be at the
Borrower's expense only if a Default has then occurred and is continuing.
Without limiting the generality of the foregoing, the Administrative Agent may
retain outside auditors to evaluate and monitor Permitted Third-Party Expenses
Borrowing Base Reports, inventory valuations and other matters relevant to the
determination of the Permitted Third-Party Expenses Borrowing Base, all at the
expense of Borrower after the occurrence and during the continuance of a
Default.

         Section 8.7 Keeping Books and Records. Each of the Loan Parties will
maintain appropriate books of record and account in accordance with GAAP
consistently applied in which true, full and correct entries will be made of
all their respective dealings and business affairs. If any changes in
accounting principles from those used in the preparation of the financial
statements referenced in Section 8.1 are hereafter required or permitted by
GAAP and are adopted by the Borrower with the concurrence of its independent
certified public accountants and such changes in GAAP result in a change in the
method of calculation or the interpretation of any of the covenants, standards
or terms contained in this Agreement, the Loan Parties and the Required Lenders
agree to amend any such affected terms and provisions so as to reflect such
changes in GAAP with the result that the criteria for evaluating the financial
condition or performance of the Loan Parties shall be the same after such
changes in GAAP as if such changes in GAAP had not been made.

         Section 8.8 Compliance with Laws. Each of the Loan Parties will comply
with all Governmental Requirements applicable to the operation of its business
(including, without limitation, the Communications Act, any rule or regulation
of the FCC or any rule or regulation of any state public utility commission),
except for instances of noncompliance that could not reasonably be expected to
have, individually or in the aggregate, a Material Adverse Effect.

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         Section 8.9 Compliance with Agreements. Each of the Loan Parties will
comply with all agreements, documents and instruments binding on it or
affecting its Properties or business, including, without limitation, all
Material Contracts, except for instances of noncompliance that could not
reasonably be expected to have, individually or in the aggregate, a Material
Adverse Effect.

         Section 8.10 Further Assurances. Each of the Loan Parties will execute
and deliver such further agreements, documents and instruments (including,
without limitation, financing statements and amendments to financing statements
specifying each item of the Collateral and the serial number therefor) and take
such further action as may be reasonably requested by the Administrative Agent
to carry out the provisions and purposes of this Agreement and the other Loan
Documents, to evidence the Obligations and to create, preserve, maintain and
perfect the Liens of the Administrative Agent for the benefit of itself and the
Lenders in and to the Collateral and the required priority of such Liens. Each
of the Loan Parties will make available to the Administrative Agent appropriate
personnel reasonably necessary to discuss the Business Plan and any updates
thereto and other information to be provided to the Administrative Agent in
accordance with Section 8.1.

         Section 8.11 ERISA. Each of the Loan Parties will, and will cause each
of their respective ERISA Affiliates to, comply with all minimum funding
requirements and all other material requirements of ERISA so as not to give
rise to any material liability thereunder.

         Section 8.12 Interest Rate Protection. The Borrower will, commencing
on or before the thirtieth (30th) day after the Closing Date, maintain in full
force and effect through the Maturity Date one or more Interest Rate Protection
Agreements reasonably satisfactory to the Administrative Agent with one or more
of the Lenders or Affiliates of the Lenders or with other counterparties
reasonably acceptable to the Administrative Agent, which Lenders or Affiliates
or other counterparties shall in each case be rated in one of the two of the
highest rating categories of Standard & Poors Corporation or Moody's Investors
Services, Inc. and otherwise reasonably acceptable to the Administrative Agent,
that enable the Borrower, for a period of the lesser of three years or six
months after the Maturity Date, to fix or place a limit upon a rate of interest
with respect to not less than an aggregate notational amount (not less than
zero) equal to fifty percent (50%) of the aggregate principal amount of the
Total Debt that does not have a fixed interest rate.

         Section 8.13 Sprint Agreements. Each of the Loan Parties will comply
with all provisions of each Sprint Agreement except to the extent that such
noncompliance may have been waived or cured within the applicable grace period
(if any) set forth in such Sprint Agreement.

         Section 8.14 Non-Consolidation. Each of the Loan Parties will: (a)
maintain entity records and books of account separate from those of any other
entity which is an Affiliate of such Loan Party; (b) not commingle its funds or
assets with those of any other entity which is an Affiliate of such Loan Party;
and (c) provide that its board of directors or other analogous governing body
will hold all appropriate meetings to authorize and approve such Person's
entity actions, which meetings will be separate from those of other Loan
Parties.

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         Section 8.15 Year 2000 Compliance. Except as may be set forth in
Schedule 8.15 and except for instances of noncompliance that the Borrower
believes could not, individually or in the aggregate, reasonably be expected to
cause a Material Adverse Effect, each of the Loan Parties will take
commercially reasonable efforts to determine that all of the material computer
software, computer hardware (whether general or special purpose), and other
similar or related items of automated, computerized or software systems that
are used or relied upon by any Loan Party in the conduct of its business is and
will continue to be Year 2000 Compliant and, without limiting the generality of
the foregoing, will not malfunction, will not cease to function, will not
generate incorrect data and will not produce incorrect results when processing,
providing or receiving (a) date- related data into and between the twentieth
and twenty-first centuries and (b) date-related data in connection with any
valid date in the twentieth and twenty-first centuries. Each of the Loan
Parties will promptly notify the Administrative Agent in the event it discovers
or determines that any computer application (including those of its suppliers
and vendors) that is material to any Loan Party's business and operations will
not be Year 2000 Compliant on a timely basis.

         Section 8.16 Trade Accounts Payable. Each of the Loan Parties will pay
all trade accounts payable before the same become more than 90 days past due,
except (a) trade accounts payable contested in good faith or (b) trade accounts
payable in an aggregate amount not to exceed $100,000 at any time outstanding
and with respect to which no proceeding to enforce collection has been
commenced or, to the knowledge of such Loan Party, threatened.

         Section 8.17 Delivery of Certain Amendments and Material Contracts.
Each of the Loan Parties will promptly deliver to the Administrative Agent any
amendment, modification, or supplement to (a) the certificate of incorporation,
articles of incorporation, certificate of formation, certificate of
organization, partnership agreement, regulations, bylaws or other
constitutional documents of any Loan Party, (b) the Sprint Agreements, or (c)
any other Material Contract to which it is a party or any Permit which it
possesses; provided, however, that any such amendment, modification or
supplement to be subject to the provisions of Section 9.15 hereof. With respect
to each Material Contract (other than purchase orders entered into in the
ordinary course of business) of any Loan Party entered into after the Closing
Date, the Borrower will deliver to the Administrative Agent a complete and
current copy of such Material Contract in a reasonably prompt fashion after the
creation thereof.

         Section 8.18 Ownership of Operating Assets. The Borrower or an
Operating Subsidiary of the Borrower will have, at all times, good legal title
of all the Operating Assets subject to no Lien other than Permitted Liens.

         Section 8.19 Observation Rights. Until such time as the earlier to
occur of (a) Nortel Networks no longer holds any Loans or Commitments hereunder
or (b) the Debt Service Coverage Ratio of the Borrower or its Consolidated
Subsidiaries has equaled or exceeded 1.00 to 1.00 (if calculated prior to the
Amortization Commencement Date, determined on a pro forma basis as if the
Amortization Commencement Date had occurred four fiscal quarters prior to such
date of calculation) for a period of four consecutive fiscal quarters, the
Borrower and/or Holdings shall give Nortel Networks notice of each meeting of
the Board of Directors of Holdings and each meeting of any committee of the
Board of Directors of Holdings not less than ten Business Days prior to the

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dates of any such meetings and allow a Person designated by Nortel Networks to
serve as an observer (the "Observer") who may attend all such meetings of the
Board of Directors of Holdings and any committee of the Board of Directors of
Holdings. The Observer will not be a director, nor entitled to vote on any
matter submitted to the Board of Directors of Holdings (or any committee of
such board), and will have no rights, duties, liabilities or obligations of a
director. The Observer may be excused at the request of a majority of the
directors present at any such meetings for discussions involving sensitive
information regarding competitors of Nortel Networks or Nortel Networks itself.
The Observer may share any information gained from presence at such meetings
with the employees, officers, directors, attorneys and advisors of Nortel
Networks who have a need to know such information in the performance of their
duties (collectively, the "Representatives"), but such information shall
otherwise be kept confidential by Nortel Networks and its Representatives to
the same extent that financial information with regard to Holdings is required
to be kept confidential in accordance with the terms of this Agreement.

         Section 8.20 Contributions to the Equity Capital of the Borrower. In
the event of the issuance of any Holdings Senior Notes, Holdings shall, and the
Borrower shall cause Holdings to, substantially concurrently with the issuance
of the Holdings Senior Notes, contribute at least $75,000,000 of the Net
Proceeds of the issuance of the Holdings Senior Notes to the Borrower as
additional equity capital in a manner reasonably satisfactory to the
Administrative Agent.

                                   ARTICLE 9

                               Negative Covenants

         Each of the Borrower, Holdings and each Operating Subsidiary hereby
covenants and agrees that, as long as the Obligations or any part thereof are
outstanding or any Lender has any Commitment hereunder, it will perform and
observe, or cause to be performed and observed, the following covenants:

         Section 9.1 Debt. The Borrower and the Operating Subsidiaries will
not, and will not permit any Subsidiary of the Borrower to, incur, create,
assume or permit to exist any Debt, except:

         (a) Debt to the Lenders pursuant to the Loan Documents;

         (b) intercompany Debt between or among the Borrower and any of its
Operating Subsidiaries or Wholly-Owned Subsidiaries incurred in the ordinary
course of business (including, without limitation, Debt owed by the Operating
Subsidiaries or Wholly-Owned Subsidiaries of the Borrower to the Borrower in
connection with loans of proceeds of the Loans made by the Borrower to such
Subsidiaries, the proceeds of which loans are used for the purposes permitted
by Section 2.10), subject to the following requirements: any and all of the
Debt permitted pursuant to this Section 9.1(b) shall be unsecured, shall be
evidenced by instruments satisfactory to the Administrative Agent which will be
pledged to the Administrative Agent for the benefit of the Administrative Agent
and the Lenders and, if payable by the Borrower, shall be subordinated to the
Obligations pursuant to a subordination agreement in form and substance
satisfactory to the Administrative Agent, provided, however, that temporary
advances made from time to time in the

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ordinary course of business not to exceed $100,000 in aggregate principal
amount at any time owing by any Operating Subsidiary or Wholly-Owned Subsidiary
of the Borrower to the Borrower shall not be required to be so evidenced,
pledged or subordinated;

         (c) unsecured Debt under the Interest Rate Protection Agreements
required to be maintained by Section 8.12, provided, however, that Debt
thereunder may be secured if such Debt constitutes a part of the Obligations;

         (d) (i) existing Debt in the principal amounts and as otherwise
described on Schedule 7.10 hereto and renewals, extensions or refinancings of
such Debt which do not increase the outstanding principal amount of such Debt,
which do not shorten the maturity of any principal of such Debt and the terms
and provisions of which are not materially more onerous than the terms and
conditions of such Debt on the Closing Date, (ii) purchase money Debt
(including Capital Lease Obligations) secured by purchase money Liens, which
Debt and Liens are permitted under and meet all of the requirements of clause
(g) of the definition of Permitted Liens contained in Section 1.1, and (iii)
additional unsecured Debt; provided, however, that the aggregate principal
amount of the Debt referred to in this Section 9.1(d) shall not exceed
$15,000,000 in aggregate amount at any time outstanding;

         (e) liabilities of the Borrower in respect of unfunded vested benefits
under any Plan if and to the extent that the existence of such liabilities will
not constitute, cause or result in a Default; and

         (f) Debt of the Borrower and its Subsidiaries to the Trustee and the
Noteholders under (and evidenced and governed by) the Subordinated Guarantees;
provided, however, that such debt may not be initially incurred (and the
Holdings Senior Notes may not be issued) after August 1, 2000.

         Section 9.2 Limitation on Liens. None of the Loan Parties will (a)
incur, create, assume or permit to exist any Lien upon any of its Property or
revenues, whether now owned or hereafter acquired, except Permitted Liens or
(b) enter into any negative pledge or similar arrangement in favor of other
creditors, other than such negative pledge or similar arrangement (i) in favor
of the Administrative Agent and the Lenders under the Loan Documents, (ii)
approved by the Administrative Agent and the Required Lenders and contained in
the Holdings Senior Notes Indenture, (iii) relating to the Capital Stock of
Unrestricted Subsidiaries required by creditors of such Unrestricted
Subsidiaries in connection with Debt incurred by them, or (iv) if and to the
extent that such purchase money Debt and Capital Lease Obligations are
permitted hereunder, in favor of other creditors under purchase money Debt and
Capital Lease Obligations with respect to the assets financed or secured
thereby.

         Section 9.3 Mergers, Etc. None of the Loan Parties will (a) become a
party to a merger or consolidation, (b) wind-up, dissolve or liquidate itself,
or (c) purchase or acquire all or a material or substantial part of the
business or Properties of any Person (except for Investments permitted under
Section 9.5); provided, however, that any Subsidiary of the Borrower, other
than an Operating Subsidiary, may merge with and into the Borrower or an
Operating Subsidiary of the Borrower if the

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Borrower or an Operating Subsidiary of the Borrower is the surviving entity,
provided that no consideration is given by the surviving entity in such merger
other than the issuance of any Capital Stock of the surviving entity and such
Capital Stock is pledged to the Administrative Agent, on behalf of the
Administrative Agent and Lenders, as security for the Obligations pursuant to
Section 9.6. The surviving entity in any such merger shall ratify the Security
Documents and other obligations of the non-surviving entity under the Loan
Documents.

         Section 9.4 Restricted Payments. The Borrower and the Operating
Subsidiaries will not, and will not permit any Subsidiary of the Borrower to,
make any Restricted Payments, except:

         (a) Subsidiaries of the Borrower may make Restricted Payments to the
Borrower, and Subsidiaries of the Borrower may pay pro rata dividends or (in
the case of entities other than corporations) equivalent distributions to the
holders of their Capital Stock on the basis of the respective ownership
interests of such holders in such Subsidiaries;

         (b) each of the Subsidiaries of the Borrower that are pass-through
entities for U.S. federal income tax purposes may pay dividends or (in the case
of entities other than corporations) equivalent distributions to the holders of
its Capital Stock in an aggregate amount not to exceed the U.S. federal income
tax liabilities of such holders that is directly attributable to their income
derived from such Subsidiary;

         (c) commencing on or after July 15, 2005 (but not prior thereto), if
and to the extent permitted by applicable law, the Borrower may declare and pay
dividends to Holdings during any fiscal year in an aggregate amount not to
exceed the accrued interest on the Holdings Senior Notes required to be paid in
cash in accordance with the Holdings Senior Notes Indenture and actually paid
in cash by Holdings, provided, however, that the entirety of the proceeds of
such dividends must be used, substantially concurrently with the payment of
such dividends by the Borrower, by Holdings to pay the same amount of accrued
interest on the Holdings Senior Notes required to be paid in accordance with
the Holdings Senior Notes Indenture, and actually paid, by Holdings in cash
(and no such dividends may be paid by the Borrower to Holdings more than 30
days prior to the applicable date upon which such accrued interest is required
to be paid and is actually paid by Holdings or in amounts exceeding the amounts
of such accrued interest required to be paid and actually paid by Holdings in
cash);

         (d) commencing on or after January 15, 2005 (but not prior thereto),
if and to the extent permitted by applicable law, the Borrower may declare and
pay dividends to Holdings during any fiscal year in an aggregate amount not to
exceed 50% of Excess Cash Flow for the fiscal year then most recently ended
(which annually-determined amounts may be accumulated over a multiple year
period before all or part of the accumulated amounts are paid to Holdings),
provided, however, that the entirety of the proceeds of such dividends must be
used, substantially concurrently with the payment of such dividends by the
Borrower, by Holdings to pay a redemption price of the same amount actually
paid by Holdings in cash in connection with an optional redemption of the
Holdings Senior Notes in accordance with Article III of the Holdings Senior
Notes Indenture (and no such dividends may be paid by the Borrower to Holdings
more than 30 days prior to the applicable date

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upon which such redemption payments are actually paid by Holdings or in amounts
exceeding the amounts of such redemption payments actually paid by Holdings in
cash); and

         (e) the Borrower and its Subsidiaries may make temporary loans or
advances to employees, officers and directors of the Loan Parties in the
ordinary course of business that do not exceed $200,000 in aggregate amount at
any time outstanding;

provided, however, that no Restricted Payments may be made pursuant to clause
(a), clause (b) or clause (c) preceding if a Default exists at the time of such
Restricted Payment or would result therefrom.

         Section 9.5 Investments. None of the Loan Parties will make or permit
to remain outstanding any advance, loan, extension of credit or capital
contribution to or investment in any Person, or purchase or own any stock,
bonds, notes, debentures or other securities of any Person, or be or become a
joint venturer with or partner of any Person (all such transactions being
herein called "Investments"), except:

         (a) Investments in obligations or securities received in settlement of
debts (created in the ordinary course of business) owing to a Loan Party;

         (b) existing Investments identified on Schedule 9.5 hereto;

         (c) Investments in securities issued or guaranteed by the U.S. or any
agency thereof with maturities of one year or less from the date of
acquisition;

         (d) Investments in certificates of deposit and Eurodollar time
deposits with maturities of six months or less from the date of acquisition,
bankers' acceptances with maturities not exceeding six months and overnight
bank deposits, in each case with any Lender or with any domestic commercial
bank having capital and surplus in excess of $500,000,000;

         (e) Investments in repurchase obligations with a term of not more than
seven days for securities of the types described in clause (c) preceding with
any Lender or with any domestic commercial bank having capital and surplus in
excess of $500,000,000;

         (f) Investments in commercial paper of a domestic issuer rated A-1 or
better or P-1 or better by Standard & Poor's Corporation or Moody's Investors
Services, Inc., respectively, maturing not more than 270 days from the date of
acquisition;

         (g) (i) Investments (other than intercompany Debt referred to in
clause (h) below) by Holdings in its Subsidiaries and by the Borrower in its
Subsidiaries, in each case existing on the Closing Date or required to occur in
accordance with this Agreement, (ii) Investments made by Holdings in the
Borrower, including, without limitation, contributions to the equity capital of
the Borrower required to be made by Holdings pursuant to this Agreement, (iii)
Investments by Holdings in its Unrestricted Subsidiaries, and (iv) additional
Investments by the Borrower in its Subsidiaries

CREDIT AGREEMENT - Page 82

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made after the Closing Date in an aggregate amount not to exceed $1,000,000
with respect to all Subsidiaries other than the Operating Subsidiaries;

         (h) intercompany Debt permitted pursuant to Section 9.1(b);

         (i) Interest Rate Protection Agreements permitted by Section 9.1; or

         (j) temporary loans or advances to employees, officers and directors
of the Loan Parties in the ordinary course of business that do not exceed
$200,000 at any time outstanding in aggregate amount;

provided, however, that no Investments may be made by any Loan Party pursuant
to subclause (iii) or (iv) of clause (g) or clause (h) preceding if a Default
exists at the time of such Investment or would result therefrom. Furthermore,
Holdings and the Borrower agree that Holdings will not own, directly or
indirectly, any Subsidiary of Holdings other than (i) the Borrower and the
Subsidiaries of the Borrower and (ii) Unrestricted Subsidiaries of Holdings.

         Section 9.6 Limitation on Issuance of Capital Stock. The Borrower and
the Operating Subsidiaries will not, and will not permit any Subsidiary of the
Borrower to, at any time issue, sell, assign or otherwise dispose of (a) any of
its Capital Stock, (b) any securities exchangeable for or convertible into or
carrying any rights to acquire any of its Capital Stock, or (c) any option,
warrant or other right to acquire any of its Capital Stock, in each case to any
Person other than Holdings (with respect to the Capital Stock of the Borrower)
or the Borrower (with respect to Capital Stock of the Subsidiaries of the
Borrower). All such Capital Stock, securities, options, warrants and other
rights issued, sold, assigned or otherwise disposed of shall be, and shall
continue to be, subject to a perfected, first priority Lien in favor of the
Administrative Agent as security for the payment and performance of the
Obligations.

         Section 9.7 Transactions with Affiliates. None of the Loan Parties
will enter into any transaction, including, without limitation, the purchase,
sale or exchange of Property or the rendering of any service, with any
Affiliate of the Borrower or other Loan Party except in the ordinary course of
and pursuant to the reasonable requirements of the Borrower's or such other
Loan Party's (as applicable) business and upon fair and reasonable terms no
less favorable to the Borrower or such other Loan Party (as applicable) than
would be obtained in a comparable arms-length transaction with a Person not an
Affiliate of the Borrower or such other Loan Party (as applicable); provided,
however, that transactions between or among the Borrower and its Affiliates may
be on terms more favorable to the Borrower than would be obtained in a
comparable arms-length transaction with a Person not an Affiliate of the
Borrower. In addition to the foregoing, no transactions between or among (a)
Affiliates of the Borrower and (b) the Borrower and its Subsidiaries relating
to the purchases of equipment from any such Affiliate or the provision of
services by any such Affiliate for the Service Area Network shall be permitted
unless the same are purchased or provided at the cost to such Affiliate.

         Section 9.8 Disposition of Property. The Borrower and the Operating
Subsidiaries will not, and will not permit any Subsidiary of the Borrower to,
sell, lease, assign, transfer or otherwise

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dispose of any of its Property (including, without limitation, the Nortel
Networks Goods and Services and the Operating Assets) except that the following
are permitted if (but only if) no Event of Default has occurred and is
continuing:

         (a) dispositions of Inventory (other than equipment) in the ordinary
course of business, and expenditures of money (including, without limitation,
money held in deposit accounts) (i) made in the ordinary course of business or
(ii) for the purpose of making Restricted Payments expressly permitted in
accordance with this Agreement or Investments expressly permitted in accordance
with this Agreement;

         (b) Asset Dispositions of Property, other than accounts and
Receivables, by made in the ordinary course of business if each of the
following conditions has been satisfied: (i)(A) the Net Proceeds from any
single Asset Disposition or series of related Asset Dispositions in any
calendar year do not exceed $500,000 and (B) the Loan Party disposing of such
Property receives fair consideration for such assets (unless the transfers of
such Property and the beneficiary of such bargain Asset Disposition is the
Borrower) and (ii) no Default exists at the time of or will result from such
Asset Disposition;

         (c) Asset Dispositions of Property by the Borrower to any Operating
Subsidiary of the Borrower or by any Operating Subsidiary of the Borrower to
the Borrower or another Operating Subsidiary of the Borrower, in each case if
each of the following conditions has been satisfied: (i) the assets sold,
disposed of or otherwise transferred to such Operating Subsidiary or the
Borrower shall continue to be subject to a perfected, first priority Lien
(except for Permitted Liens, if any, which are expressly permitted by the Loan
Documents to have priority over the Liens in favor of the Administrative Agent)
in favor of the Administrative Agent and the Lenders, and (ii) no Default
exists at the time of or will result from such Asset Disposition; and

         (d) dispositions of Property no longer used or useful in the ordinary
course of business, including, without limitation, dispositions of equipment
being exchanged or replaced with comparable or better equipment;

provided, however, that, except to the limited extent expressly permitted in
clauses (b) and (d) of this Section 9.8, the Borrower and its Operating
Subsidiaries may not sell, lease, assign, transfer or otherwise dispose of the
Service Area Network (including, without limitation, the Nortel Networks
Equipment and the Nortel Networks Software) or the "Operating Assets" as such
term is defined or used in any Sprint Management Agreement pursuant to the
Sprint Agreements or otherwise unless the Obligations are paid in full and all
Commitments have terminated or expired.

         Section 9.9 Sale and Leaseback. None of the Loan Parties will enter
into any arrangement with any Person pursuant to which it leases from such
Person real or personal Property that has been or is to be sold or transferred,
directly or indirectly, by it to such Person; provided, however, that the
Borrower and its Operating Subsidiaries may enter into such sale/leaseback
transactions with respect to towers pursuant to which the aggregate amount of
rent payable during any calendar year does not exceed $3,000,000 if the
agreements evidencing and governing such

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transactions have been approved by the Administrative Agent, which approval
shall not be unreasonably conditioned, withheld or delayed.

         Section 9.10 Lines of Business. None of the Borrower or any of its
Subsidiaries will (a) engage in any line or lines of business activity other
than the construction and operation of the Service Area Network, the
performance of the Sprint Agreements and the conduct of related
telecommunications businesses described in and contemplated by the Business
Plan or (b) build-out any area other than the Service Area or engage in
operations outside the Service Area, in each case as contemplated by the
Business Plan; provided, however, that, for all purposes of this Section 9.10,
the term "Service Area," as such term is used in the definition of the term
"Service Area Network" and as such term is used in clause (b) preceding, shall
exclude all New Areas. Holdings and the Borrower agree that Holdings will not
(i) engage in any business other than the ownership of the Capital Stock of the
Borrower and the Unrestricted Subsidiaries and matters incidental thereto,
including the raising of capital, or (ii) own any material Properties or assets
other than the Capital Stock of the Borrower and the Unrestricted Subsidiaries.
The Borrower, the Operating Subsidiaries and Holdings agree that (A) Alamosa
Texas shall, at all times, own all of the "Operating Assets" as such term is
defined in the Sprint Management Agreement (Alamosa Texas) and (B) Alamosa
Wisconsin shall, at all times, own all of the "Operating Assets" as such term
is defined in the Sprint Management Agreement (Alamosa Wisconsin).

         Section 9.11 Environmental Protection. None of the Loan Parties will
(a) use (or permit any tenant to use) any of its Properties for the handling,
processing, storage, transportation or disposal of any Hazardous Material
except in compliance with applicable Environmental Laws, (b) generate any
Hazardous Material except in compliance with applicable Environmental Laws, (c)
conduct any activity that is likely to cause a Release or threatened Release of
any Hazardous Material in violation of any Environmental Law, or (d) otherwise
conduct any activity or use any of its Properties in any manner, that violates
or is likely to violate any Environmental Law or create any Environmental
Liabilities for which any Loan Party would be responsible, except for
circumstances or events described in clauses (a) through (d) preceding that
could not, individually or in the aggregate, reasonably be expected to have a
Material Adverse Effect.

         Section 9.12 Intercompany Transactions. Except as may be expressly
permitted or required by the Loan Documents and except as may be contained in
the Holdings Senior Notes Indenture as approved by the Administrative Agent and
the Required Lenders, none of the Loan Parties will create or otherwise cause
or permit to exist or become effective any consensual encumbrance or
restriction of any kind on the ability of any Subsidiary of Holdings or the
Borrower to (a) pay dividends or make any other distribution to Holdings or the
Borrower or any of their Subsidiaries in respect of such Subsidiary's Capital
Stock or with respect to any other interest or participation in, or measured
by, its profits, (b) pay any indebtedness owed to Holdings or the Borrower or
any of their Subsidiaries, (c) make any loan or advance to Holdings or the
Borrower or any of their Subsidiaries, or (d) sell, lease or transfer any of
its Property to Holdings or the Borrower or any of their Subsidiaries.

         Section 9.13 Management Fees. None of the Loan Parties will pay any
management fees (other than the Sprint PCS Fees permitted to be paid in
accordance with Section 9.17).

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         Section 9.14 Supply Agreement. None of the Loan Parties will terminate
the Supply Agreement prior to the later to occur of the Amortization
Commencement Date or the satisfaction in full of the Borrower's purchase
commitments under the Supply Agreement.

         Section 9.15 Modification of Certain Agreements. None of the Loan
Parties will consent to or implement any termination, amendment, modification,
supplement or waiver of (a) the certificate of incorporation, articles of
incorporation, certificate of formation, certificate of organization,
partnership agreement, regulations, bylaws or other constitutional documents of
any Loan Party, (b) the Sprint Agreements, (c) the Business Plan, (d) the
Holdings Senior Notes Indenture or the other Holdings Senior Notes Documents,
or (e) any other Material Contract to which it is a party or any Permit which
it possesses; provided, however, that the Loan Parties may amend or modify (i)
the documents referred to in clause (a) and clause (d) preceding if and to the
extent that such amendment or modification is not substantive or material and
could not reasonably be expected to be adverse to the Administrative Agent or
the Lenders, provided, however, that none of such documents referred to in
clause (a) preceding may be amended or modified as they relate to, in any way,
any capital contribution to Holdings or the Borrower or any obligation or
agreement relating thereto and (ii) the Sprint Agreements and the Material
Contracts referred to in clauses (b) and (e) preceding, respectively, if and to
the extent that such amendment or modification could not reasonably be expected
to be materially adverse to any Loan Party or the Administrative Agent or any
of the Lenders.

         Section 9.16 ERISA. None of the Loan Parties will:

         (a) allow, or take (or permit any ERISA Affiliate to take) any action
which would cause, any unfunded or unreserved liability for benefits under any
Plan (exclusive of any Multiemployer Plan) to exist or to be created that
exceeds $200,000 with respect to any such Plan or $500,000 with respect to all
such Plans in the aggregate on either a going concern or a wind-up basis; or

         (b) with respect to any Multiemployer Plan, allow, or take (or permit
any ERISA Affiliate to take) any action which would cause, any unfunded or
unreserved liability for benefits under any Multiemployer Plan to exist or to
be created, either individually as to any such Plan or in the aggregate as to
all such Plans, that could, upon any partial or complete withdrawal from or
termination of any such Multiemployer Plan or Plans, have a Material Adverse
Effect.

         Section 9.17 Sprint PCS Fees. None of the Loan Parties will make any
prepayment of any Sprint PCS Fees prior to the regularly scheduled due date for
the payment of such fees.

         Section 9.18 No Prepayment of Debt, Etc. None of the Loan Parties will
make any optional prepayment or distribution on account of, or voluntarily
purchase, acquire, redeem or retire, any Debt prior to 30 days before its
originally stated maturity (or its stated maturity as of the Closing Date in
the case of Debt outstanding on the Closing Date), or in the case of interest,
its stated due date, or directly or indirectly become obligated to do any of
the foregoing by amending the terms thereof or otherwise, except for:

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         (a) prepayments of the Loans or other Obligations pursuant to or as
permitted by the Loan Documents;

         (b) prepayments of intercompany Debt referred to in clause (b) of
Section 9.1 if the obligor with respect to such Debt is a Subsidiary of the
Borrower and if the payee of such Debt is the Borrower or a parent entity of
such obligor;

         (c) prepayments of the Debt referred to in clauses (ii) and (iii) of
clause (d) of Section 9.1;

         (d) prepayments made with the proceeds of new Debt incurred for the
purpose of refinancing the Debt being prepaid, provided that (i) no portion of
such new Debt matures or is required to be prepaid, purchased or otherwise
retired earlier than the corresponding portion of the Debt being prepaid
(including as a result of any prepayment or redemption upon the occurrence of a
condition), (ii) such new Debt (A) is subordinated to the Obligations to at
least the same extent as the Debt being refinanced if such Debt is subordinated
debt or (B) is permitted in accordance with this Agreement, and (iii) no
Default then exists or would result from such prepayment or refinancing;

         (e) prepayments of trade payables incurred in the ordinary course of
any Loan Party's business (other than Sprint PCS Fees) and not overdue by more
than 120 days;

         (f) commencing on or after February 15, 2005 (but not prior thereto),
optional redemptions of the Holdings Senior Notes by Holdings in accordance
with Article III of the Holdings Senior Notes Indenture, other than optional
redemptions with the proceeds of public equity offerings by Holdings referred
to in clause (g) succeeding; and

         (g) commencing on or after February 15, 2003 (but not prior thereto),
optional redemptions of the Holdings Senior Notes by Holdings with the proceeds
of public equity offerings by Holdings, other than the Holdings Public
Offering, in accordance with Article III of the Holdings Senior Notes
Indenture.

In addition, none of the Loan Parties will prepay any rent or other obligations
under any operating lease or any other Material Contract prior to 90 days
before the originally stated due date therefor (or the due date therefor as of
the Closing Date in the case of operating leases or Material Contracts in
existence on the Closing Date).

                                   ARTICLE 10

                              Financial Covenants

         Section 10.1 Total Debt to Total Capitalization.

         (a) Borrower. The Borrower and the Operating Subsidiaries will not
permit the ratio of (i) the Total Debt of the Borrower and its Consolidated
Subsidiaries (exclusive of the Debt to the Trustee and the Noteholders under,
and evidenced and governed by, the Subordinated Guarantees)

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outstanding at the end of any of the calendar quarters set forth on Schedule
10.1 to (ii) the Total Capitalization of the Borrower on such date, to exceed
the ratio set forth opposite such date on such Schedule.

         (b) Holdings. The Loan Parties will not permit the ratio of (i) the
Total Debt of Holdings and its Consolidated Subsidiaries outstanding at the end
of any calendar quarter to (ii) the Total Capitalization of Holdings on such
date, to exceed (A) 0.75 to 1.00 at all times during which the Senior Debt of
Holdings and its Consolidated Subsidiaries is equal to or greater than 40% of
the Total Capitalization of Holdings and its Consolidated Subsidiaries and (B)
0.80 to 1.00 at all times during which the Senior Debt of Holdings and its
Consolidated Subsidiaries is less than 40% of the Total Capitalization of
Holdings and its Consolidated Subsidiaries.

         Section 10.2 Total Debt to Annualized EBITDA. The Borrower and the
Operating Subsidiaries will not permit the ratio of (a) the Total Debt of the
Borrower and its Consolidated Subsidiaries (exclusive of the Debt to the
Trustee and the Noteholders under, and evidenced and governed by, the
Subordinated Guarantees) outstanding at the end of any of the calendar quarters
set forth on Schedule 10.2 to (b) Annualized EBITDA for the calendar quarter
ending on such date, to exceed the ratio set forth opposite such date on such
Schedule.

         Section 10.3 Annualized EBITDA. The Borrower and the Operating
Subsidiaries will not permit Annualized EBITDA at the end of any of the
calendar quarters set forth on Schedule 10.3 to be less than the amount set
forth opposite such date on such Schedule.

         Section 10.4 Fixed Charge Coverage. The Borrower and the Operating
Subsidiaries will not permit the ratio of (a) EBITDA for any of the calendar
quarters ending on any of the dates set forth on Schedule 10.4 plus cash
balances and Availability on such date to (b) Consolidated Fixed Charges for
the immediately succeeding calendar quarter, to be less than the ratio set
forth opposite such date on such Schedule.

         Section 10.5 Capital Expenditures. The Borrower and the Operating
Subsidiaries will not permit cumulative Capital Expenditures for the period
beginning on January 1, 1999 and ending on any of the dates set forth on
Schedule 10.5 to exceed the amount set forth opposite such date on such
Schedule.

         Section 10.6 Quarterly Minimum Revenue Levels. The Borrower and the
Operating Subsidiaries will not permit Gross Revenues for any calendar quarter
ending on any of the dates set forth on Schedule 10.6 to be less than the
amount set forth opposite such date on such Schedule.

         Section 10.7 Wireless Subscribers. The Borrower and the Operating
Subsidiaries will not permit Wireless Subscribers at the end of any calendar
quarter ending on any of the dates set forth in Schedule 10.7 to be less than
the amount set forth opposite such date on such Schedule.

         Section 10.8 Operating Leases. The Borrower and the Operating
Subsidiaries will not, and will not permit its Subsidiaries to, enter into or
become party to Operating Leases, other than tower leases and transport
facility leases, that in the aggregate provide for payments during any calendar

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year in excess of $3,000,000. The Borrower and the Operating Subsidiaries will
not, and will not permit its Subsidiaries to, enter into or become party to
Operating Leases which are tower leases that in the aggregate provide for
payments during any calendar year in excess of $13,000,000.

                                   ARTICLE 11

                                    Default

         Section 11.1 Events of Default. Each of the following shall be deemed
an "Event of Default":

         (a) (i) The Borrower shall fail to pay, repay or prepay when due, any
amount of principal or interest owing to the Administrative Agent or any Lender
pursuant to this Agreement or any other Loan Document, or (ii) the Borrower
shall fail to pay, within two Business Days after the due date thereof, any
fee, expense or other amount or other Obligation owing to the Administrative
Agent or any Lender pursuant to this Agreement or any other Loan Document.

         (b) Any representation or warranty made or deemed made by or on behalf
of any Loan Party in any Loan Document or in any certificate, report, notice or
financial statement furnished at any time in connection with this Agreement or
any other Loan Document shall be false, misleading or erroneous in any material
respect when made or deemed to have been made.

         (c) Any Loan Party shall fail to perform, observe or comply with any
covenant, agreement or term contained in Section 5.1, 8.1(e), 8.2, Article 9 or
Article 10; any Loan Party shall fail to perform, observe or comply with any
covenant, agreement or term contained in Article 5 or Section 8.1, 8.3, 8.5,
8.6, 8.7, 8.8, 8.9, 8.10, 8.13, 8.14 and 8.19, and such failure is not remedied
or waived within ten days after such failure commenced; or any Loan Party shall
fail to perform, observe or comply with any other covenant, agreement or term
contained in this Agreement or any other Loan Document (other than covenants to
pay the Obligations) and such failure is not remedied or waived within the
earlier to occur of 30 days after such failure commenced or, if a different
grace period is expressly made applicable in such other Loan Documents, such
applicable grace period.

         (d) Any Loan Party or any Sprint PCS signatory to any Sprint
Management Agreement ceases to be Solvent or shall admit in writing its
inability to, or be generally unable to, pay its debts as such debts become
due.

         (e) Any Loan Party or any Sprint PCS signatory to any Sprint
Management Agreement shall (i) apply for or consent to the appointment of, or
the taking of possession by, a receiver, custodian, trustee, liquidator or
administrator of itself or of all or a substantial part of its Property, (ii)
admit in writing its inability to, or be generally unable to, pay its debts as
such debts become due, subject to any applicable grace periods, (iii) make a
general assignment for the benefit of its creditors, (iv) commence a voluntary
case under the United States Bankruptcy Code (as now or hereafter in effect,
the "Bankruptcy Code"), (v) file a petition or take any other action seeking to
take advantage of any other law providing for the relief of debtors, the
marshaling of assets or relating to bankruptcy, insolvency, reorganization,
liquidation, dissolution, arrangement or winding up, or

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composition or readjustment of debts, (vi) fail to controvert in a timely or
appropriate manner, or acquiesce in writing to, any petition filed against it
in an involuntary case under the Bankruptcy Code or other applicable
Governmental Requirement, (vii) dissolve, or (viii) take any entity action for
the purpose of effecting any of the foregoing.

         (f) A proceeding or case shall be commenced, without the application
or consent of any Loan Party or any Sprint PCS signatory to any Sprint
Management Agreement, in any court of competent jurisdiction, seeking (i) the
liquidation, reorganization, dissolution, arrangement, winding up, or
composition or readjustment of its debts, (ii) the appointment of a trustee,
receiver, custodian, examiner, liquidator, administrator or the like of it or
of all or any substantial part of its Property, or (iii) similar relief in
respect of it, under any law providing for the relief of debtors or relating to
bankruptcy, insolvency, reorganization, liquidation, dissolution, arrangement
or winding up, or composition or readjustment of debts, and such proceeding or
case shall continue undismissed, or an order, judgment or decree approving or
ordering any of the foregoing shall be entered and continue unstayed and in
effect, for a period of 60 or more days; or an order for relief shall be
entered in an involuntary case under the Bankruptcy Code against any Loan Party
and shall continue unstayed and in effect for any period of 60 consecutive
days.

         (g) Any Loan Party shall fail to discharge within a period of 30 days
after the commencement thereof any attachment, sequestration, forfeiture or
similar proceeding or proceedings involving an aggregate amount in excess of
$500,000 against any of its Properties.

         (h) A final judgment or judgments for the payment of money in excess
of $500,000 in the aggregate shall be rendered by a court or courts against any
Loan Party on claims not covered by insurance and the same shall not be
discharged, bonded or a stay of execution thereof shall not be procured, within
30 days from the date of entry thereof and such Loan Party shall not, within
said period of 30 days, or such longer period during which execution of the
same shall have been stayed, appeal therefrom and cause the execution thereof
to be stayed during such appeal.

         (i) Any Loan Party shall fail to pay when due any principal of or
interest on any Debt of such Loan Party (other than the Obligations) having
(either individually or in the aggregate) a principal amount of at least
$500,000 or the maturity of any such Debt shall have been accelerated, or any
such Debt shall have been required to be prepaid prior to the stated maturity
thereof, or any event shall have occurred (and shall not have been waived or
otherwise cured) that permits (or, with the giving of notice or lapse of time
or both, would permit) any holder or holders of such Debt or any Person acting
on behalf of such holder or holders to accelerate the maturity thereof or
require any such prepayment.

         (j) This Agreement or any other Loan Document shall cease to be in
full force and effect or shall be declared null and void, or the validity or
enforceability thereof shall be successfully contested or challenged by any
Loan Party and the effect thereof shall be materially adverse to the
Administrative Agent and/or the Lenders; or any Lien created or purported to be
created by the Loan Documents shall for any reason cease to be or fail to be a
valid, first priority perfected Lien upon any of the Collateral purported to be
covered thereby.

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<PAGE>   98

         (k) Any of the following events shall occur or exist with respect to
any Loan Party or any ERISA Affiliate: (i) any Prohibited Transaction involving
any Plan; (ii) any Reportable Event with respect to any Pension Plan; (iii) the
filing under Section 4041 of ERISA of a notice of intent to terminate any
Pension Plan or the termination of any Pension Plan; (iv) any event or
circumstance that could reasonably be expected to constitute grounds entitling
the PBGC to institute proceedings under Section 4042 of ERISA for the
termination of, or for the appointment of a trustee to administer, any Pension
Plan, or the institution by the PBGC of any such proceedings; (v) any
"accumulated funding deficiency" (as defined in Section 302 of ERISA or Section
412 of the Code), whether or not waived, shall exist with respect to any
Pension Plan; or (vi) complete or partial withdrawal under Section 4201 or 4204
of ERISA from a Multiemployer Plan or the reorganization, insolvency or
termination of any Pension Plan; and in each case above, such event or
condition, together with all other events or conditions, if any, have subjected
or could in the reasonable opinion of Required Lenders subject any Loan Party
or any ERISA Affiliate to any tax, penalty or other liability to a Plan, a
Multiemployer Plan, the PBGC or otherwise (or any combination thereof) which in
the aggregate exceed or could reasonably be expected to exceed $500,000.

         (l) The occurrence of any breach or default by the Borrower or any
other Loan Party under the Supply Agreement (after giving effect to any grace
or cure period specified therein) which breach or default entitles Nortel
Networks to exercise a right or remedy under or in connection with the Supply
Agreement.

         (m) The termination of any Sprint Agreement, or the occurrence of (i)
any "Event of Termination" as defined in any Sprint Agreement, or (ii) any
breach or default under any Consent and Agreement (other than a breach or
default by the Administrative Agent) which breach or default entitles the
Administrative Agent to exercise a right or remedy under or in connection with
such Consent and Agreement.

         (n) Any termination, revocation or non-renewal by the FCC of one or
more of the PCS Licenses or by Sprint PCS of any right of any Loan Party to use
any PCS Licenses, or any termination, revocation or non-renewal by any state
public utility commission of any other material Permit of any Loan Party.

         (o) The occurrence of any Material Adverse Effect.

         (p) The occurrence of any Change in Control.

         (q) The breach by any Loan Party of, or the termination, invalidity or
unenforceability of, any Consent and Agreement.

         (r) Any sale, transfer or other disposition of the Service Area
Network or any material portion thereof.

         (s) If, at any time, the subordination provisions of any of the
Approved Subordinated Debt Documents shall be invalidated or shall otherwise
cease to be in full force and effect.

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         (t) If, at any time, any event or circumstance shall occur that gives
(i) any holder of any Approved Subordinated Debt the right to request or
require Holdings or the Borrower or any other Loan Party to redeem, purchase,
repurchase or prepay any Approved Subordinated Debt or (ii) any holder of any
of the Holdings Senior Notes the right to require Holdings to redeem, purchase,
repurchase or prepay any of the Holdings Senior Notes.

         (u) The occurrence of (i) a default under (including, without
limitation, a "Default" as such term is used or defined in) any Approved
Subordinated Debt Document, unless (A) such default has been waived, cured or
consented to in accordance with such documents, (B) such default is not a
payment default, (C) the maturity of the Debt affected thereby has not been
accelerated, (D) a blockage under such Approved Subordinated Debt Document has
not been invoked, and (E) such waiver or consent is not made in connection with
any amendment or modification of any such Approved Subordinated Debt Documents
or in connection with any payment to the holders of any Approved Subordinated
Debt, (ii) a payment default under (including, without limitation, a payment
"Default" as such term is used or defined in) any Approved Subordinated Debt
Document, (iii) an event of default under (including, without limitation, an
"Event of Default" as such term is used or defined in) any Approved
Subordinated Debt Document, or (iv) any acceleration of the maturity of any
Approved Subordinated Debt.

         (v) The occurrence of any Holdings Senior Notes Event of Default or
any "Change of Control" as such term is defined in the Holdings Senior Notes
Indenture.

         Section 11.2 Remedies. If any Event of Default shall occur and be
continuing, the Administrative Agent may and, if directed by the Required
Lenders, the Administrative Agent shall do any one or more of the following:

         (a) Acceleration. Declare all outstanding principal of and accrued and
unpaid interest on the Loans and all other amounts payable by the Borrower or
any other Loan Party under the Loan Documents immediately due and payable, and
the same shall thereupon become immediately due and payable, without notice,
demand, presentment, notice of dishonor, notice of acceleration, notice of
intent to accelerate, protest or other formalities of any kind, all of which
are hereby expressly waived by the Borrower and the other Loan Parties;

         (b) Termination of Commitments. Terminate each of the Commitments
without notice to the Borrower or any other Loan Party;

         (c) Judgment. Reduce any claim to judgment;

         (d) Foreclosure. Foreclose or otherwise enforce any Lien granted to
the Administrative Agent for the benefit of the Administrative Agent and the
Lenders to secure payment and performance of the Obligations in accordance with
the terms of the Loan Documents; or

         (e) Rights. Exercise any and all rights and remedies afforded by the
laws of the State of New York or any other jurisdiction, by any of the Loan
Documents, by equity or otherwise;

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provided, however, that upon the occurrence of an Event of Default under
Section 11.1(e) or Section 11.1(f), the Commitments of all of the Lenders shall
immediately and automatically terminate, and the outstanding principal of and
accrued and unpaid interest on the Loans and all other amounts payable by the
Borrower or any other Loan Party under the Loan Documents shall thereupon
become immediately and automatically due and payable, without notice, demand,
presentment, notice of dishonor, notice of acceleration, notice of intent to
accelerate, protest or other formalities of any kind, all of which are hereby
expressly waived by the Borrower and the other Loan Parties.

         Section 11.3 Performance by the Administrative Agent, etc.. If the
Borrower or any other Loan Party shall fail to perform any covenant or
agreement in accordance with the terms of the Loan Documents, the
Administrative Agent may perform or attempt to perform, or may cause any Lender
(with the consent of such Lender) to perform or attempt to perform, such
covenant or agreement on behalf of the Borrower or such other Loan Party (as
applicable). In such event, the Borrower shall, at the request of the
Administrative Agent, promptly pay any amount expended by the Administrative
Agent or the Lenders in connection with such performance or attempted
performance to the Administrative Agent at its Principal Office, together with
interest thereon at the applicable Default Rate from and including the date of
such expenditure to but excluding the date such expenditure is paid in full.
Notwithstanding the foregoing, it is expressly agreed that neither the
Administrative Agent nor any Lender shall have any liability or responsibility
for the performance of any obligation of the Borrower or any other Loan Party
or any other Person under this Agreement or any of the other Loan Documents.

                                   ARTICLE 12

                            The Administrative Agent

         Section 12.1 Appointment, Powers and Immunities. Each Lender hereby
irrevocably appoints and authorizes the Administrative Agent to act as its
agent hereunder and under the other Loan Documents with such powers as are
specifically delegated to the Administrative Agent by the terms of this
Agreement and the other Loan Documents, together with such other powers as are
reasonably incidental thereto. Neither the Administrative Agent nor any of its
Affiliates, officers, directors, employees, attorneys or agents shall be liable
for any action taken or omitted to be taken by any of them hereunder or
otherwise in connection with this Agreement or any of the other Loan Documents
except for its or their own gross negligence or willful misconduct. Without
limiting the generality of the preceding sentence, the Administrative Agent (a)
may treat the payee of any Note as the holder thereof until the Administrative
Agent receives written notice of the assignment or transfer thereof signed by
such payee and in form satisfactory to the Administrative Agent, (b) shall have
no duties or responsibilities except those expressly set forth in this
Agreement and the other Loan Documents, and shall not by reason of this
Agreement or any other Loan Document be a trustee or fiduciary for any Lender,
(c) shall not be required to initiate any litigation or collection proceedings
hereunder or under any other Loan Document except to the extent requested by
the Required Lenders, (d) shall not be responsible to the Lenders for any
recitals, statements, representations or warranties contained in this Agreement
or any other Loan Document, or any certificate or other document referred to or
provided for in, or received by any of them under, this

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Agreement or any other Loan Document, or for the value, validity,
effectiveness, enforceability or sufficiency of this Agreement or any other
Loan Document or any other document referred to or provided for herein or
therein or for any failure by any Person to perform any of its obligations
hereunder or thereunder, (e) may consult with legal counsel (including counsel
for any Loan Party), independent public accountants and other experts selected
by it and shall not be liable for any action taken or omitted to be taken in
good faith by it in accordance with the advice of such counsel, accountants or
experts, and (f) shall incur no liability under or in respect of any Loan
Document by acting upon any notice, consent, certificate or other instrument or
writing reasonably believed by it to be genuine and signed or sent by the
proper party or parties. As to any matters not expressly provided for by this
Agreement, the Administrative Agent shall in all cases be fully protected in
acting, or in refraining from acting, hereunder in accordance with instructions
signed by the Required Lenders, and such instructions of the Required Lenders
and any action taken or failure to act pursuant thereto shall be binding on all
of the Lenders; provided, however, that the Administrative Agent shall not be
required to take any action which exposes the Administrative Agent to liability
or which is contrary to this Agreement or any other Loan Document or applicable
law. The Administrative Agent shall not be deemed to have any fiduciary
relationship with any Lender or any Loan Party, and no implied covenants,
functions, responsibilities, duties, obligations or liabilities shall be read
into this Agreement or otherwise exist against the Administrative Agent.
Without limiting the generality of the foregoing, the use of the term "agent"
in this Agreement with respect to the Administrative Agent is not intended to
connote any fiduciary or other express or implied obligation arising under
agency doctrine of any applicable law; instead, such term is used merely as a
matter of market custom and is intended to create or reflect only an
administrative relationship among independent contracting parties.

         Section 12.2 Rights of Administrative Agent as a Lender. With respect
to its Commitments, the Loans made by it and the Note(s) issued to it, Nortel
Networks (and any successor acting as Administrative Agent) in its capacity as
a Lender hereunder shall have the same rights and powers hereunder as any other
Lender and may exercise the same as though it were not acting as the
Administrative Agent, and the term "Lender" or "Lenders" shall, unless the
context otherwise indicates, include the Administrative Agent in its individual
capacity. The Administrative Agent and its Affiliates may (without having to
account therefor to any Lender) accept deposits from, lend money to, act as
trustee under indentures of, provide merchant banking services to, own
securities of, and generally engage in any kind of banking, trust or other
business with, any Loan Party or any of its Affiliates and any other Person who
may do business with or own securities of any Loan Party or any of its
Affiliates, all as if it were not acting as the Administrative Agent and
without any duty to account therefor to the Lenders. Without limiting the
generality of the foregoing, it is contemplated that (a) Nortel Networks will
be the holder of the warrants issued by Holdings and (b) Nortel Networks and/or
an Affiliate of Nortel Networks may purchase equity securities of Holdings.

         Section 12.3 Defaults. The Administrative Agent shall not be deemed to
have knowledge or notice of the occurrence of a Default (other than the
non-payment of principal of or interest on the Loans or of commitment fees)
unless the Administrative Agent has received notice from a Lender or the
Borrower specifying such Default and stating that such notice is a "notice of
default". In the event that the Administrative Agent receives such a notice of
the occurrence of a Default, the Administrative Agent shall give prompt notice
thereof to the Lenders (and shall give each Lender

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prompt notice of each such non-payment). The Administrative Agent shall
(subject to Section 12.1) take such action with respect to such Default as
shall be directed by the Required Lenders, provided that unless and until the
Administrative Agent shall have received such directions, the Administrative
Agent may (but shall not be obligated to) take such action, or refrain from
taking such action, with respect to such Default as it shall seem advisable and
in the best interest of the Lenders.

         SECTION 12.4 INDEMNIFICATION. EACH LENDER HEREBY AGREES TO INDEMNIFY
THE ADMINISTRATIVE AGENT FROM AND HOLD THE ADMINISTRATIVE AGENT HARMLESS
AGAINST (TO THE EXTENT NOT REIMBURSED UNDER SECTIONS 13.1 AND 13.2, BUT WITHOUT
LIMITING THE OBLIGATIONS OF THE BORROWER UNDER SECTIONS 13.1 AND 13.2), RATABLY
IN ACCORDANCE WITH ITS PRO RATA SHARE (CALCULATED ON THE BASIS OF ITS
COMMITMENT PERCENTAGE OF THE AGGREGATE COMMITMENTS), ANY AND ALL LIABILITIES
(INCLUDING, WITHOUT LIMITATION, ENVIRONMENTAL LIABILITIES), OBLIGATIONS,
LOSSES, DAMAGES, PENALTIES, ACTIONS, JUDGMENTS, DEFICIENCIES, SUITS, COSTS,
EXPENSES (INCLUDING ATTORNEYS' FEES) AND DISBURSEMENTS OF ANY KIND OR NATURE
WHATSOEVER WHICH MAY BE IMPOSED ON, INCURRED BY OR ASSERTED AGAINST THE
ADMINISTRATIVE AGENT IN ANY WAY RELATING TO OR ARISING OUT OF ANY OF THE LOAN
DOCUMENTS OR ANY ACTION TAKEN OR OMITTED TO BE TAKEN BY THE ADMINISTRATIVE
AGENT UNDER OR IN RESPECT OF ANY OF THE LOAN DOCUMENTS; PROVIDED, THAT NO
LENDER SHALL BE LIABLE FOR ANY PORTION OF THE FOREGOING TO THE EXTENT CAUSED BY
THE ADMINISTRATIVE AGENT'S GROSS NEGLIGENCE OR WILLFUL MISCONDUCT. WITHOUT
LIMITATION OF THE FOREGOING, IT IS THE EXPRESS INTENTION OF THE LENDERS THAT
THE ADMINISTRATIVE AGENT SHALL BE INDEMNIFIED HEREUNDER FROM AND HELD HARMLESS
AGAINST ALL OF SUCH LIABILITIES (INCLUDING, WITHOUT LIMITATION, ENVIRONMENTAL
LIABILITIES), OBLIGATIONS, LOSSES, DAMAGES, PENALTIES, ACTIONS, JUDGMENTS,
DEFICIENCIES, SUITS, COSTS, EXPENSES (INCLUDING ATTORNEYS' FEES) AND
DISBURSEMENTS OF ANY KIND OR NATURE DIRECTLY OR INDIRECTLY ARISING OUT OF OR
RESULTING FROM THE SOLE OR CONTRIBUTORY NEGLIGENCE OF THE ADMINISTRATIVE AGENT
(EXCEPT TO THE EXTENT THE SAME ARE CAUSED BY THE ADMINISTRATIVE AGENT'S GROSS
NEGLIGENCE OR WILLFUL MISCONDUCT). WITHOUT LIMITING ANY OTHER PROVISION OF THIS
SECTION 12.4, EACH LENDER AGREES TO REIMBURSE THE ADMINISTRATIVE AGENT PROMPTLY
UPON DEMAND FOR ITS PRO RATA SHARE (CALCULATED ON THE BASIS OF ITS COMMITMENT
PERCENTAGE OF THE AGGREGATE COMMITMENTS) OF ANY AND ALL OUT-OF-POCKET EXPENSES
(INCLUDING ATTORNEYS' FEES) INCURRED BY THE ADMINISTRATIVE AGENT IN CONNECTION
WITH THE PREPARATION, EXECUTION, DELIVERY, ADMINISTRATION, MODIFICATION,
AMENDMENT OR ENFORCEMENT (WHETHER THROUGH NEGOTIATIONS, LEGAL PROCEEDINGS OR
OTHERWISE) OF, OR LEGAL ADVICE IN RESPECT OF RIGHTS OR RESPONSIBILITIES UNDER,
THE

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LOAN DOCUMENTS, TO THE EXTENT THAT THE ADMINISTRATIVE AGENT IS NOT PROMPTLY
REIMBURSED FOR SUCH EXPENSES BY THE BORROWER.

         Section 12.5 Independent Credit Decisions. Each Lender agrees that it
has independently and without reliance on the Administrative Agent or any other
Lender, and based on such documents and information as it has deemed
appropriate, made its own credit analysis of the Borrower and the other Loan
Parties and its own decision to enter into this Agreement and that it will,
independently and without reliance upon the Administrative Agent or any other
Lender, and based upon such documents and information as it shall deem
appropriate at the time, continue to make its own analysis and decisions in
taking or not taking action under this Agreement or any of the other Loan
Documents. The Administrative Agent shall not be required to keep itself
informed as to the performance or observance by any Loan Party of this
Agreement or any other Loan Document or to inspect the Properties or books of
any Loan Party (or any other Person). Except for notices, reports and other
documents and information expressly required to be furnished to the Lenders by
the Administrative Agent hereunder or under the other Loan Documents, the
Administrative Agent shall not have any duty or responsibility to provide any
Lender with any credit or other financial information concerning the affairs,
financial condition or business of any Loan Party which may come into the
possession of the Administrative Agent or any of its Affiliates.

         Section 12.6 Several Commitments. The Commitments and other
obligations of the Lenders under this Agreement are several. The default by any
Lender in making a Loan in accordance with any of its Commitments shall not
relieve the other Lenders of their obligations under this Agreement. In the
event of any default by any Lender in making any Loan, each nondefaulting
Lender shall be obligated to make its Loan but shall not be obligated to
advance the amount which the defaulting Lender was required to advance
hereunder. In no event shall any Lender be required to advance an amount or
amounts with respect to any of the Loans which would in the aggregate exceed
such Lender's Commitment with respect to such Loans. No Lender shall be
responsible for any act or omission of any other Lender.

         Section 12.7 Successor Administrative Agent. Subject to the
appointment and acceptance of a successor Administrative Agent as provided
below, the Administrative Agent may resign at any time by giving notice thereof
to the Lenders and the Borrower. Upon any such resignation, the Required
Lenders will have the right to appoint another Lender as a successor
Administrative Agent. If no successor Administrative Agent shall have been so
appointed by the Required Lenders and shall have accepted such appointment
within 30 days after the retiring Administrative Agent's giving of notice of
resignation, then the retiring Administrative Agent may, on behalf of the
Lenders, appoint a successor Administrative Agent, which shall be a commercial
bank organized under the laws of the U.S. or any state thereof or of a foreign
country if acting through its U.S. branch and having combined capital and
surplus of at least $100,000,000. Upon the acceptance of its appointment as
successor Administrative Agent, such successor Administrative Agent shall
thereupon succeed to and become vested with all rights, powers, privileges,
immunities and duties of the resigning Administrative Agent, and the resigning
Administrative Agent shall be discharged from its duties and obligations under
this Agreement and the other Loan Documents. After any Administrative Agent's
resignation as Administrative Agent, the provisions of this Article 12 shall
continue in effect for its benefit in respect of any actions taken or omitted
to be taken by it while it was the

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Administrative Agent. Each Administrative Agent (including each successor
Administrative Agent) agrees that, so long as it is acting as Administrative
Agent under this Agreement, it shall be a Lender under this Agreement.

                                   ARTICLE 13

                                 Miscellaneous

         Section 13.1 Expenses. The Borrower hereby agrees, on demand, to pay
or reimburse the Administrative Agent and each of the Lenders for paying: (a)
all reasonable out-of-pocket costs and expenses of the Administrative Agent
accrued in connection with the drafting, preparation, negotiation, execution
and/or delivery of this Agreement and the other Loan Documents, and any and all
waivers, amendments, modifications, renewals, extensions and supplements of or
to the Loan Documents, and the syndication of the Commitments and the Loans,
including, without limitation, the reasonable fees and expenses of legal
counsel (including all local counsel) for the Administrative Agent, (b) all
out-of-pocket costs and expenses of the Administrative Agent and the Lenders in
connection with any Default, the exercise of any right or remedy and the
enforcement of this Agreement or any other Loan Document or any term or
provision hereof or thereof, including, without limitation, the fees and
expenses of all legal counsel for the Administrative Agent and/or any Lender,
(c) all transfer, stamp, documentary or other similar taxes, assessments or
charges levied by any Governmental Authority in respect of this Agreement or
any of the other Loan Documents, (d) all costs, expenses, assessments and other
charges incurred in connection with any filing, registration, recording or
perfection of any Lien contemplated by this Agreement or any other Loan
Document, and (e) all reasonable out-of-pocket costs and expenses incurred by
the Administrative Agent in connection with due diligence, computer services,
copying, appraisals, environmental audits, collateral audits, field exams,
insurance, consultants and search reports. Notwithstanding the foregoing
provisions of this Section 13.1, the legal fees and related expenses of counsel
to the Administrative Agent shall be subject to the limitations therefor
specified in the Administrative Agent's Letter.

         SECTION 13.2 INDEMNIFICATION. EACH OF THE LOAN PARTIES HEREBY JOINTLY
AND SEVERALLY AGREES TO INDEMNIFY THE ADMINISTRATIVE AGENT AND EACH LENDER AND
EACH AFFILIATE THEREOF AND THEIR RESPECTIVE OFFICERS, DIRECTORS, EMPLOYEES,
ATTORNEYS AND AGENTS FROM, AND HOLD EACH OF THEM HARMLESS AGAINST, ANY AND ALL
LOSSES, LIABILITIES (INCLUDING, WITHOUT LIMITATION, ENVIRONMENTAL LIABILITIES),
CLAIMS, DAMAGES, PENALTIES, JUDGMENTS, DISBURSEMENTS, COSTS AND EXPENSES
(INCLUDING REASONABLE ATTORNEYS' AND CONSULTANTS' FEES) TO WHICH ANY OF THEM
MAY BECOME SUBJECT WHICH DIRECTLY OR INDIRECTLY ARISE FROM OR RELATE TO (A) THE
NEGOTIATION, EXECUTION, DELIVERY, PERFORMANCE, ADMINISTRATION OR ENFORCEMENT OF
ANY OF THE LOAN DOCUMENTS, INCLUDING, WITHOUT LIMITATION, THE EXERCISE OF ANY
FORECLOSURE RIGHT OR OTHER RIGHT OR REMEDY WHETHER OR NOT SUCH EXERCISE IS IN
COMPLIANCE WITH LAWS AFFECTING OTHER PERSONS OR RESULTS IN DAMAGES PAYABLE TO
OTHER PERSONS, (B)

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ANY OF THE TRANSACTIONS CONTEMPLATED BY THE LOAN DOCUMENTS, (C) ANY BREACH BY
ANY LOAN PARTY OF ANY MATERIAL REPRESENTATION, WARRANTY, COVENANT OR OTHER
AGREEMENT CONTAINED IN ANY OF THE LOAN DOCUMENTS, (D) THE USE OR PROPOSED USE
OF ANY LOAN, (E) THE PRESENCE, RELEASE, THREATENED RELEASE, DISPOSAL, REMOVAL
OR CLEANUP OF ANY HAZARDOUS MATERIAL LOCATED ON, ABOUT, WITHIN OR AFFECTING ANY
OF THE PROPERTIES OF ANY LOAN PARTY OR ANY OF THEIR AFFILIATES, EXCEPT TO THE
EXTENT THAT THE LOSS, DAMAGE OR CLAIM IS THE DIRECT RESULT OF GROSS NEGLIGENCE
OR WILLFUL MISCONDUCT OF THE PERSON TO BE INDEMNIFIED, OR (F) ANY
INVESTIGATION, LITIGATION OR OTHER PROCEEDING, INCLUDING, WITHOUT LIMITATION,
ANY THREATENED INVESTIGATION, LITIGATION OR OTHER PROCEEDING RELATING TO ANY OF
THE FOREGOING; BUT EXCLUDING ANY OF THE FOREGOING TO THE EXTENT CAUSED BY THE
GROSS NEGLIGENCE OR WILLFUL MISCONDUCT OF THE PERSON TO BE INDEMNIFIED. WITHOUT
LIMITING ANY PROVISION OF THIS AGREEMENT OR OF ANY OTHER LOAN DOCUMENT, IT IS
THE EXPRESS INTENTION OF THE PARTIES HERETO THAT EACH PERSON TO BE INDEMNIFIED
UNDER THIS SECTION 13.2 SHALL BE INDEMNIFIED FROM AND HELD HARMLESS AGAINST ANY
AND ALL LOSSES, LIABILITIES (INCLUDING, WITHOUT LIMITATION, ENVIRONMENTAL
LIABILITIES), CLAIMS, DAMAGES, PENALTIES, JUDGMENTS, DISBURSEMENTS, COSTS AND
EXPENSES (INCLUDING REASONABLE ATTORNEYS' FEES) ARISING OUT OF OR RESULTING
FROM THE SOLE OR CONTRIBUTORY NEGLIGENCE OF SUCH PERSON. WITHOUT PREJUDICE TO
THE SURVIVAL OF ANY OTHER TERM OR PROVISION OF THIS AGREEMENT, THE OBLIGATIONS
OF THE LOAN PARTIES UNDER THIS SECTION 13.2 SHALL SURVIVE THE REPAYMENT OF THE
LOANS AND OTHER OBLIGATIONS AND TERMINATION OF THE COMMITMENTS.

         Section 13.3 Limitation of Liability. None of the Administrative
Agent, any Lender or any Affiliate, officer, director, employee, attorney or
agent thereof shall be liable for any error of judgment or act done in good
faith, or be otherwise liable or responsible under any circumstances whatsoever
(including such Person's negligence), except for such Person's gross negligence
or willful misconduct. None of the Administrative Agent, any Lender or any
Affiliate, officer, director, employee, attorney or agent thereof shall have
any liability with respect to, and each of the Borrower and the other Loan
Parties hereby waives, releases and agrees not to sue any of them upon, any
claim for any special, indirect, incidental or consequential damages suffered
or incurred by any Loan Party or any of its Affiliates in connection with,
arising out of or in any way related to this Agreement or any of the other Loan
Documents, or any of the transactions contemplated by this Agreement or any of
the other Loan Documents. Each of the Loan Parties hereby waives, releases and
agrees not to sue the Administrative Agent or any Lender or any of their
respective Affiliates, officers, directors, employees, attorneys or agents for
exemplary or punitive damages in respect of any claim in connection with,
arising out of or in any way related to this Agreement or any of the other Loan
Documents, or any of the transactions contemplated by this Agreement or any of
the other Loan Documents.

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         Section 13.4 No Duty. All attorneys, accountants, appraisers and other
professional Persons and consultants retained by the Administrative Agent and
the Lenders shall have the right to act exclusively in the interest of the
Administrative Agent and the Lenders and shall have no duty of disclosure, duty
of loyalty, duty of care or other duty or obligation of any type or nature
whatsoever to any Loan Party or any of its Affiliates or any other Person.

         Section 13.5 No Fiduciary Relationship. The relationship between each
Loan Party and each Lender is solely that of debtor and creditor, and neither
the Administrative Agent nor any Lender has any fiduciary or other special
relationship with any Loan Party or any of its Affiliates, and no term or
condition of any of the Loan Documents shall be construed so as to deem the
relationship between any Loan Party and any Lender, or such Affiliate and any
Lender, to be other than that of debtor and creditor. No joint venture or
partnership is created by this Agreement among the Lenders or among any Loan
Party or any of its Affiliates and the Lenders.

         Section 13.6 Equitable Relief. Each of the Loan Parties recognizes
that, in the event it fails to pay, perform, observe or discharge any or all of
the Obligations, any remedy at law may prove to be inadequate relief to the
Administrative Agent and the Lenders. Each of the Loan Parties therefore agrees
that the Administrative Agent and the Lenders, if the Administrative Agent or
the Lenders so request, shall be entitled to temporary and permanent injunctive
relief in any such case without the necessity of proving actual damages.

         Section 13.7 No Waiver; Cumulative Remedies. No failure on the part of
the Administrative Agent or any Lender to exercise and no delay in exercising,
and no course of dealing with respect to, any right, power or privilege under
this Agreement or any other Loan Document shall operate as a waiver thereof,
nor shall any single or partial exercise of any right, power or privilege under
this Agreement or any other Loan Document preclude any other or further
exercise thereof or the exercise of any other right, power or privilege. The
rights and remedies provided for in this Agreement and the other Loan Documents
are cumulative and not exclusive of any rights and remedies provided by law.

         Section 13.8 Successors and Assigns.

         (a) This Agreement shall be binding upon and inure to the benefit of
the parties hereto and their respective successors and assigns. Neither the
Borrower nor any other Loan Party may assign or transfer any of its rights or
obligations under this Agreement or any other Loan Document without the prior
written consent of the Administrative Agent and the Lenders. Any Lender may
sell participations in all or a portion of its rights and obligations under
this Agreement and the other Loan Documents (including, without limitation, all
or a portion of its Commitments and the Loans owing to it); provided, however,
that (i) such Lender's obligations under this Agreement and the other Loan
Documents (including, without limitation, its Commitments) shall remain
unchanged, (ii) such Lender shall remain solely responsible to the Borrower for
the performance of such obligations, (iii) such Lender shall remain the holder
of its Notes for all purposes of this Agreement, (iv) the Borrower shall
continue to deal solely and directly with such Lender in connection with such
Lender's rights and obligations under this Agreement and the other Loan
Documents, and (v) the Lenders shall not grant any participation under which
the participant shall have the right to approve

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(or under which the consent of the participant must be obtained prior to the
Lenders' being able to approve) any amendment or waiver of this Agreement or
the other Loan Documents, except to the extent that such amendment or waiver
(A) increases any Commitment, (B) reduces the interest rate or the amount of
principal or fees applicable to the Loans or Commitments in which such
participant is participating, (C) extends any Maturity Date, (D) releases any
of the Collateral (except as provided for herein or in any other Loan Document)
or any guaranty of the Obligations, or (E) releases any Loan Party from its
monetary Obligations under any of the Loan Documents.

         (b) The Loan Parties and each of the Lenders agree that any Lender
(the "Assigning Lender") may at any time assign to one or more Eligible
Assignees all or any part of its rights and/or obligations under this Agreement
and the other Loan Documents (including, without limitation, its Commitments
and/or Loans) (each an "Assignee"); provided, however, that (i) each such
assignment may be of a varying percentage of the Assigning Lender's rights
and/or obligations under this Agreement and the other Loan Documents and may
relate to some but not all of such rights and/or obligations, (ii) except in
the case of (A) an assignment of all of a Lender's rights and obligations under
this Agreement and the other Loan Documents or (B) an assignment by a Lender to
an Affiliate of such Lender, to another Lender or to an Approved Fund, the
amount of the Commitment(s) and/or Loans of the Assigning Lender being assigned
pursuant to each assignment (determined as of the date of the Assignment and
Acceptance with respect to such assignment) shall in no event be less than
$5,000,000 calculated based upon the aggregate amount of the Commitment(s)
and/or Loans assigned and (iii) the parties to each such assignment shall
execute and deliver to the Administrative Agent for its acceptance and
recording in the Register (as defined below), an Assignment and Acceptance,
together with the Note subject to such assignment, and a processing and
recordation fee of $3,500. Upon such execution, delivery, acceptance and
recording, from and after the effective date specified in each Assignment and
Acceptance, which effective date shall be at least five Business Days after the
execution thereof or such other date as may be approved by the Administrative
Agent, (1) the Assignee thereunder shall be a party hereto as a "Lender" and,
to the extent that rights and obligations hereunder have been assigned to it
pursuant to such Assignment and Acceptance, have the rights and obligations of
a Lender hereunder and under the other Loan Documents, and (2) the Assigning
Lender thereunder shall, to the extent that rights and obligations hereunder
have been assigned by it pursuant to such Assignment and Acceptance, relinquish
its rights and be released from its obligations under this Agreement and the
other Loan Documents (and, in the case of an Assignment and Acceptance covering
all or the remaining portion of a Lender's rights and obligations under the
Loan Documents, such Lender shall cease to be a party thereto, provided that
such Lender's rights under Article 4, Section 13.1 and Section 13.2 accrued
through the date of assignment shall continue). Holdings and the Borrower will
provide full and prompt assistance to each Lender as it may reasonably request
from time to time in connection with such Lender's efforts to assign its
Commitments and/or Loans or sell any participation interest therein. Such
assistance shall include, without limitation, making senior officers of
Holdings and the Borrower available for meetings with prospective Lenders and
participants and providing (in a timely manner) such assistance as may be
reasonably requested by such Lender and/or its advisors, including, without
limitation, providing information to and responding to inquiries from such
prospective Lenders and participants with respect to the businesses,
operations, business plan, financial condition and results of operations of the
Loan Parties.

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         (c) By executing and delivering an Assignment and Acceptance, the
Assigning Lender thereunder and the Assignee thereunder confirm to and agree
with each other and the other parties hereto as follows: (i) other than as
provided in such Assignment and Acceptance, such Assigning Lender makes no
representation or warranty and assumes no responsibility with respect to any
statements, warranties or representations made in or in connection with the
Loan Documents or the execution, legality, validity, enforceability,
genuineness, sufficiency or value of the Loan Documents or any other instrument
or document furnished pursuant thereto; (ii) such Assigning Lender makes no
representation or warranty and assumes no responsibility with respect to the
financial condition or results of operations of any Loan Party or any of its
Affiliates or the performance or observance by any Loan Party or any of its
Affiliates of its obligations under the Loan Documents; (iii) such Assignee
confirms that it has received a copy of the Loan Documents, together with
copies of the financial statements referred to in Section 7.2 and such other
documents and information as it has deemed appropriate to make its own credit
analysis and decision to enter into such Assignment and Acceptance; (iv) such
Assignee will, independently and without reliance upon the Administrative Agent
or such Assigning Lender and based on such documents and information as it
shall deem appropriate at the time, continue to make its own credit decisions
in taking or not taking action under this Agreement and the other Loan
Documents; (v) such Assignee confirms that it is an Eligible Assignee; (vi)
such Assignee appoints and authorizes the Administrative Agent to take such
action as agent on its behalf and exercise such powers under the Loan Documents
as are delegated to the Administrative Agent by the terms thereof, together
with such powers as are reasonably incidental thereto; and (vii) such Assignee
agrees that it will perform in accordance with their terms all of the
obligations which by the terms of the Loan Documents are required to be
performed by it as a Lender.

         (d) The Administrative Agent shall maintain at its Principal Office a
copy of each Assignment and Acceptance delivered to and accepted by it and a
register for the recordation of the names and addresses of the Lenders and the
Commitments of, and principal amount of the Loans owing to, each Lender from
time to time (the "Register"). The entries in the Register shall be conclusive
and binding for all purposes, absent manifest error, and the Loan Parties, the
Administrative Agent and the Lenders may treat each Person whose name is
recorded in the Register as a Lender hereunder for all purposes under the Loan
Documents. The Register shall be available for inspection by the Borrower or
any Lender at any reasonable time and from time to time upon reasonable prior
notice.

         (e) Upon its receipt of an Assignment and Acceptance executed by an
Assigning Lender and Assignee representing that it is an Eligible Assignee,
together with the Note(s) subject to such assignment, the Administrative Agent
shall, if such Assignment and Acceptance has been completed and is in
substantially the form of Exhibit A hereto, (i) accept such Assignment and
Acceptance, (ii) record the information contained therein in the Register, and
(iii) give prompt written notice thereof to the Borrower. Within five Business
Days after its receipt of such notice, the Borrower, at its expense, shall
execute and deliver to the Administrative Agent in exchange for each
surrendered Note evidencing the Loans assigned, a new Note evidencing such
Loans payable to the order of such Eligible Assignee in an amount equal to such
Loans assigned to it and, if the Assigning Lender has retained any Loans, a new
Note evidencing each such Loans payable to the order of the Assigning Lender in
the amount of such Loans retained by it (each such promissory note shall
constitute a

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"Note" for purposes of the Loan Documents). Such new Notes shall be dated the
effective date of such Assignment and Acceptance and shall otherwise be in
substantially the form of Exhibit B hereto.

         (f) Any Lender may, in connection with any assignment or participation
or proposed assignment or participation pursuant to this Section 13.8, disclose
to the Assignee or participant or proposed Assignee or participant any
information relating to any Loan Party or any of its Affiliates furnished to
such Lender by or on behalf of the any Loan Party or any of its Affiliates;
provided that each such actual or proposed Assignee or participant shall agree
to be bound by the provisions of Section 13.20.

         (g) Any Lender may assign and pledge any Note held by it to any
Federal Reserve Bank or the U.S. Treasury as collateral security pursuant to
Regulation A of the Board of Governors of the Federal Reserve System and any
operating circular issued by such Federal Reserve System and/or Federal Reserve
Bank; provided, however, that any payment made by the Borrower for the benefit
of such assigning and/or pledging Lender in accordance with the terms of the
Loan Documents shall satisfy the Borrower's obligations under the Loan
Documents in respect thereof to the extent of such payment. No such assignment
and/or pledge shall release the assigning and/or pledging Lender from its
obligations hereunder.

         (h) The Borrower shall maintain, or cause to be maintained, a register
(the "Registered Note Register") (which, at the request of the Borrower (which
request the Borrower makes by the execution of this Agreement) shall be kept by
the Administrative Agent on behalf of the Borrower at no extra charge to the
Borrower at the address to which notices to the Administrative Agent are to be
sent hereunder) on which it shall enter the name of the registered owner of
each of the Loans which is evidenced by a Registered Note. Notwithstanding
anything to the contrary contained in this Section 13.8, a Registered Note and
the Loans evidenced thereby may be assigned or otherwise transferred in whole
or in part only by registration of such assignment or transfer of such
Registered Note and the Loans evidenced thereby on the Registered Note Register
(and each Registered Note shall expressly so provide). Any assignment or
transfer of all or part of such Loans and the Registered Note evidencing the
same shall be registered on the Registered Note Register only upon surrender
for registration of assignment or transfer of the Registered Note evidencing
such Loans, duly endorsed by (or accompanied by a written instrument of
assignment or transfer duly executed by) the registered noteholder thereof, and
thereupon one or more new Registered Notes in the same aggregate principal
amount shall be issued to the designated assignee(s) or transferee(s). Prior to
the due presentment for registration of transfer of any Registered Note, the
Borrower and the Administrative Agent shall treat the Person in whose name such
Loans and the Registered Note(s) evidencing the same are registered as the
owner thereof for the purpose of receiving all payments thereon and for all
other purposes, notwithstanding any notice to the contrary. The Registered Note
Register shall be available for inspection by the Borrower and any Lender at
any reasonable time upon reasonable prior notice.

         (i) The Loan Parties will not become a party to any loan agreement,
credit agreement or similar agreement which restricts or prohibits the right or
ability of any lender which is a party thereto to become a Lender under this
Agreement.

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         (j) Holdings and the Borrower shall provide prompt assistance to the
Administrative Agent and the Lenders in connection with their respective
efforts in syndicating the Loans and Commitments. Such assistance shall include
making senior officers and other representatives of Holdings and the Borrower
and their Affiliates available for meetings with prospective Lenders and
providing, in a timely manner, such assistance as may be reasonably requested
by the Administrative Agent or its advisors, including, without limitation,
providing information to and responding to inquiries from prospective Lenders
with respect to the business, operations, Business Plan, results and other
matters relating to the business of Holdings, the Borrower and the other Loan
Parties.

         Section 13.9 Survival. All representations and warranties made or
deemed made in this Agreement or any other Loan Document or in any document,
statement or certificate furnished in connection with this Agreement shall
survive the execution and delivery of this Agreement and the other Loan
Documents and the making of the Loans, and no investigation by the
Administrative Agent or any Lender or any closing shall affect the
representations and warranties or the right of the Administrative Agent or any
Lender to rely upon them. Without prejudice to the survival of any other
obligation of any of the Loan Parties hereunder or under the other Loan
Documents, the obligations of the Borrower and the other Loan Parties under
Article 4 and Sections 13.1 and 13.2 shall survive repayment of the Loans and
the Reimbursement Obligations and the other Obligations.

         SECTION 13.10 ENTIRE AGREEMENT. THIS AGREEMENT, THE NOTES AND THE
OTHER LOAN DOCUMENTS REFERRED TO HEREIN EMBODY THE FINAL, ENTIRE AGREEMENT
AMONG THE PARTIES HERETO AND SUPERSEDE ANY AND ALL PRIOR COMMITMENTS, TERM
SHEETS, AGREEMENTS, REPRESENTATIONS AND UNDERSTANDINGS, WHETHER WRITTEN OR
ORAL, RELATING TO THE SUBJECT MATTER HEREOF AND MAY NOT BE CONTRADICTED OR
VARIED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OR
DISCUSSIONS OF THE PARTIES HERETO. THERE ARE NO UNWRITTEN ORAL AGREEMENTS
BETWEEN OR AMONG (A) ANY ONE OR MORE OF THE LOAN PARTIES AND (B) ANY ONE OR
MORE OF THE ADMINISTRATIVE AGENT AND/OR THE LENDERS.

         Section 13.11 Amendments. No amendment or waiver of any provision of
this Agreement, the Notes or any other Loan Document to which any Loan Party is
a party, nor any consent to any departure by any Loan Party therefrom, shall in
any event be effective unless the same shall be agreed or consented to by the
Required Lenders and such Loan Party in writing, and each such waiver or
consent shall be effective only in the specific instance and for the specific
purpose for which given; provided, however, that no amendment, waiver or
consent shall, unless in writing and signed by all of the Lenders and the
Borrower, do any of the following: (a) increase the Commitments of the Lenders
(or any Lender) or subject the Lenders to any additional obligations; (b)
reduce the principal of, or interest on, the Loans or any fees or other amounts
payable hereunder; (c) postpone any date fixed for any payment (including,
without limitation, any mandatory prepayment) of principal of, or interest on,
the Loans or any fees or other amounts payable hereunder; (d) change the
Commitment Percentages or the aggregate unpaid principal amount of the Loans or
the number or interests of the Lenders which shall be required for the Lenders
or any of them to take any action under this Agreement; (e) change any
provision contained in Section 3.2, 3.3

CREDIT AGREEMENT - Page 103

<PAGE>   111

or 5.1 or this Section 13.11 or modify the definition of "Required Lenders," or
"Permitted Third- Party Expenses Borrowing Base" contained in Section 1.1; or
(f) except as expressly authorized by this Agreement, release any Collateral
from any of the Liens created by the Security Documents; and provided further,
however, that no amendment, waiver or consent relating to Sections 12.1, 12.2,
12.3, 12.4 or 12.5 shall require the agreement of the Borrower or any other
Loan Party. Notwithstanding anything to the contrary contained in this Section
13.11, no amendment, waiver or consent shall be made with respect to (i)
Article 12 hereof without the prior written consent of the Administrative
Agent, (ii) the definitions of "Nortel Networks Equipment", "Nortel Networks
Goods and Services", "Nortel Networks Software", "Permitted Third-Party
Expenses", "Permitted Third-Party Expenses Borrowing Base", "Supply Agreement"
or Section 2.5, 2.9 or 2.10 hereof without the prior written consent of Nortel
Networks (whether or not Nortel Networks is then a Lender hereunder), or (iii)
any condition precedent set forth in Article 6 with respect to the making of
any Tranche A Loans, Tranche B Loans or Tranche C Loans without the prior
written consent of the Lenders that hold, at the time of such amendment, waiver
or consent, at least a majority (in Dollar amount) of the Tranche A
Commitments, Tranche B Commitments or Tranche C Commitments, respectively.

         Section 13.12 Maximum Interest Rate.

         (a) No interest rate specified in this Agreement or any other Loan
Document shall at any time exceed the Maximum Rate. If at any time the interest
rate (the "Contract Rate") for any Obligation shall exceed the Maximum Rate,
thereby causing the interest accruing on such Obligation to be limited to the
Maximum Rate, then any subsequent reduction in the Contract Rate for such
Obligation shall not reduce the rate of interest on such Obligation below the
Maximum Rate until the aggregate amount of interest accrued on such Obligation
equals the aggregate amount of interest which would have accrued on such
Obligation if the Contract Rate for such Obligation had at all times been in
effect.

         (b) Notwithstanding anything to the contrary contained in this
Agreement or the other Loan Documents, none of the terms and provisions of this
Agreement or the other Loan Documents shall ever be construed to create a
contract or obligation to pay interest at a rate in excess of the Maximum Rate;
and neither the Administrative Agent nor any Lender shall ever charge, receive,
take, collect, reserve or apply, as interest on the Obligations, any amount in
excess of the Maximum Rate. The parties hereto agree that any interest, charge,
fee, expense or other obligation provided for in this Agreement or in the other
Loan Documents which constitutes interest under applicable law shall be, ipso
facto and under any and all circumstances, limited or reduced to an amount
equal to the lesser of (i) the amount of such interest, charge, fee, expense or
other obligation that would be payable in the absence of this Section 13.12(b)
or (ii) an amount, which when added to all other interest payable under this
Agreement and the other Loan Documents, equals the Maximum Rate. If,
notwithstanding the foregoing, the Administrative Agent or any Lender ever
contracts for, charges, receives, takes, collects, reserves or applies as
interest any amount in excess of the Maximum Rate, such amount which would be
deemed excessive interest shall be deemed a partial payment or prepayment of
principal of the Obligations and treated hereunder as such; and if the
Obligations, or applicable portions thereof, are paid in full, any remaining
excess shall promptly be paid to the Borrower. In determining whether the
interest paid or payable, under any specific

CREDIT AGREEMENT - Page 104

<PAGE>   112

contingency, exceeds the Maximum Rate, the Borrower and the other Loan Parties,
the Administrative Agent and the Lenders shall, to the maximum extent permitted
by applicable law, (i) characterize any nonprincipal payment as an expense, fee
or premium rather than as interest, (ii) exclude voluntary prepayments and the
effects thereof, and (iii) amortize, prorate, allocate and spread in equal or
unequal parts the total amount of interest throughout the entire contemplated
term of the Obligations, or applicable portions thereof, so that the interest
rate does not exceed the Maximum Rate at any time during the term of the
Obligations; provided that, if the unpaid principal balance is paid and
performed in full prior to the end of the full contemplated term thereof, and
if the interest received for the actual period of existence thereof exceeds the
Maximum Rate, the Administrative Agent and/or the Lenders, as appropriate,
shall refund to the Borrower the amount of such excess and, in such event, the
Administrative Agent and the Lenders shall not be subject to any penalties
provided by any laws for contracting for, charging, receiving, taking,
collecting, reserving or applying interest in excess of the Maximum Rate.

         Section 13.13 Notices. All notices and other communications provided
for in this Agreement and the other Loan Documents to which the Borrower,
Holdings or any Operating Subsidiary is a party shall be given or made by
telecopy or in writing and telecopied, mailed by certified mail return receipt
requested or delivered to the intended recipient at the "Address for Notices"
specified below its name on the signature pages hereof (or, with respect to a
Lender that becomes a party to this Agreement pursuant to an assignment made in
accordance with Section 13.8, in the Assignment and Acceptance executed by it);
or, as to any party, at such other address as shall be designated by such party
in a notice to each other party given in accordance with this Section 13.13.
Except as otherwise provided in this Agreement, all such communications shall
be deemed to have been duly given when transmitted by telecopy or personally
delivered or, in the case of a mailed notice, upon receipt, in each case given
or addressed as aforesaid; provided, however, that notices to the
Administrative Agent shall be deemed given when received by the Administrative
Agent.

         SECTION 13.14 GOVERNING LAW; SUBMISSION TO JURISDICTION; SERVICE OF
PROCESS. EXCEPT AS MAY BE EXPRESSLY STATED TO THE CONTRARY IN CERTAIN LOAN
DOCUMENTS, THIS AGREEMENT, THE NOTES AND THE OTHER LOAN DOCUMENTS SHALL BE
GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW
YORK (WITHOUT REGARD TO CONFLICTS OF LAWS PRINCIPLES) AND EACH OF THE PARTIES
HERETO CHOOSE THE LAWS OF THE STATE OF NEW YORK TO GOVERN THIS AGREEMENT
PURSUANT TO N.Y. GEN. OBLIG. LAW SECTION 5-1401 (CONSOL. 1995) AND APPLICABLE
LAWS OF THE U.S. EACH OF THE LOAN PARTIES HEREBY SUBMITS TO THE NON-EXCLUSIVE
JURISDICTION OF EACH OF (1) THE U.S. DISTRICT COURT FOR THE SOUTHERN DISTRICT
OF NEW YORK, (2) ANY NEW YORK STATE COURT SITTING IN NEW YORK, NEW YORK, (3)
THE U.S. DISTRICT COURT FOR THE NORTHERN DISTRICT OF TEXAS, AND (4) ANY TEXAS
STATE COURT SITTING IN DALLAS COUNTY, TEXAS, FOR THE PURPOSES OF ALL LEGAL
PROCEEDINGS ARISING OUT OF OR RELATING TO THIS AGREEMENT, ANY OTHER LOAN
DOCUMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY. EACH OF THE LOAN
PARTIES HEREBY IRREVOCABLY CONSENTS TO

CREDIT AGREEMENT - Page 105

<PAGE>   113

THE SERVICE OF ANY AND ALL PROCESS IN ANY SUCH ACTION OR PROCEEDING BY THE
MAILING OF COPIES OF SUCH PROCESS TO SUCH PERSON AT ITS ADDRESS FOR NOTICES SET
FORTH UNDERNEATH ITS SIGNATURE HERETO OR SET FORTH IN ANY OTHER LOAN DOCUMENT.
EACH OF THE LOAN PARTIES HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT
PERMITTED BY LAW, ANY OBJECTION WHICH IT MAY NOW OR HEREAFTER HAVE TO THE
LAYING OF THE VENUE OF ANY SUCH PROCEEDING BROUGHT IN SUCH A COURT AND ANY
CLAIM THAT ANY SUCH PROCEEDING BROUGHT IN SUCH A COURT HAS BEEN BROUGHT IN AN
INCONVENIENT FORUM.

         Section 13.15 Counterparts. This Agreement may be executed in one or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

         Section 13.16 Severability. Any provision of this Agreement held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Agreement and the effect thereof shall be
confined to the provision held to be invalid or illegal.

         Section 13.17 Headings. The headings, captions and arrangements used
in this Agreement are for convenience only and shall not affect the
interpretation of this Agreement.

         Section 13.18 Construction. Each of the Loan Parties, the
Administrative Agent and the Lenders acknowledges that it has had the benefit
of legal counsel of its own choice and has been afforded an opportunity to
review this Agreement and the other Loan Documents with its legal counsel and
that this Agreement and the other Loan Documents shall be construed as if
jointly drafted by the parties hereto and thereto.

         Section 13.19 Independence of Covenants. All covenants hereunder shall
be given independent effect so that if a particular action or condition is not
permitted by any of such covenants, the fact that it would be permitted by an
exception to, or be otherwise within the limitations of, another covenant shall
not avoid the occurrence of a Default if such action is taken or such condition
exists.

         Section 13.20 Confidentiality.

         (a) Lenders' Obligations. Each Lender agrees to exercise its best
efforts to keep any information delivered or made available by the Borrower to
it which is clearly indicated to be confidential information, confidential from
anyone other than Persons employed or retained by such Lender who are or are
expected to become engaged in evaluating, approving, structuring or
administering the Loans; provided, however, that nothing herein shall prevent
any Lender from disclosing such information (a) to any other Lender, (b) to any
Person if reasonably incidental to the administration of the Loans, (c) upon
the order of any court or administrative agency, (d) upon the request or demand
of any regulatory agency or authority having jurisdiction over such Lender, (e)
which has been publicly disclosed, (f) in connection with any litigation to
which the Administrative Agent, any Lender or their respective Affiliates may
be a party, (g) to the extent

CREDIT AGREEMENT - Page 106

<PAGE>   114

reasonably required in connection with the exercise of any right or remedy
under the Loan Documents, (h) to such Lender's legal counsel, independent
auditors and affiliates, and (i) to any actual or proposed participant or
Assignee of all or part of its rights hereunder, so long as such actual or
proposed participant or Assignee agrees to be bound by the provisions of this
Section 13.20; provided, further, however, that each Lender shall not disclose
any "Confidential Information" (as such term is defined in any Sprint
Management Agreement) except as permitted by Section 12.2 of any Sprint
Management Agreement (as amended) and as modified by Section 14 of any Consent
and Agreement.

         (b) Loan Parties' and Affiliates' Obligations. Each of the Loan
Parties will, and will cause its Affiliates to, keep the terms and provisions
of this Agreement and the other Loan Documents confidential from anyone other
than individuals employed or retained by the Loan Parties who are or are
expected to become engaged in financial matters or matters relating to
compliance with the Loan Documents, provided that nothing herein shall prevent
any such Person from disclosing such information (i) to any other Loan Party,
(ii) upon the order of any court or administrative agency, (iii) upon the
request or demand of any Governmental Authority having jurisdiction over any
Loan Party, (iv) which has been publicly disclosed, and (v) to a Loan Party's
legal counsel and independent auditors; provided, however, that the Borrower
and the other Loan Parties will deliver to the Administrative Agent written
notice of any intention or obligation of any Loan Party to deliver or provide a
copy of this Agreement or any other Loan Document or any term or provision
hereof or thereof to any Governmental Authority at least ten Business Days
prior to the initial date upon which any such delivery or provision occurs and
each of the Loan Parties shall use all reasonable efforts to redact or delete
from such copy or such term or provision such terms or provisions or language
relating to rates of interest, fees, financial covenants, availability and
other terms or provisions of a sensitive nature as may be requested by the
Administrative Agent to be so redacted or deleted before the same is so
delivered or provided. Without limiting the generality of the foregoing, each
of the Loan Parties agrees that it will not, and will not permit any of its
Affiliates to, without the prior written consent of the Administrative Agent,
issue or publish a press release, tombstone or other similar announcement or
publication relating to this Agreement or any other Loan Document or the
transactions contemplated hereby unless it is required to do so by the order of
any court or administrative agency or in accordance with applicable law.

         SECTION 13.21 WAIVER OF JURY TRIAL. TO THE FULLEST EXTENT PERMITTED BY
APPLICABLE LAW, EACH OF THE LOAN PARTIES, THE ADMINISTRATIVE AGENT AND THE
LENDERS HEREBY IRREVOCABLY AND EXPRESSLY WAIVES ALL RIGHT TO A TRIAL BY JURY IN
ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED UPON CONTRACT, TORT OR
OTHERWISE) ARISING OUT OF OR RELATING TO ANY OF THE LOAN DOCUMENTS OR THE
TRANSACTIONS CONTEMPLATED THEREBY OR THE ACTIONS OF ANY LOAN PARTY, THE
ADMINISTRATIVE AGENT OR ANY LENDER IN THE NEGOTIATION, ADMINISTRATION OR
ENFORCEMENT THEREOF.

         Section 13.22 Approvals and Consent. Except as may be expressly
provided to the contrary in this Agreement or in the other Loan Documents (as
applicable), in any instance under this Agreement of the other Loan Documents
where the approval, consent or exercise of judgment of the

CREDIT AGREEMENT - Page 107

<PAGE>   115

Administrative Agent or any Lender is requested or required, (a) the granting
or denial of such approval or consent and the exercise of such judgment shall
be within the sole discretion of the Administrative Agent or such Lender,
respectively, and the Administrative Agent and such Lender shall not, for any
reason or to any extent, be required to grant such approval or consent or to
exercise such judgment in any particular manner, regardless of the
reasonableness of the request or the action or judgment of the Administrative
Agent or such Lender, and (b) no approval or consent of the Administrative
Agent or any Lender shall in any event be effective unless the same shall be in
writing and the same shall be effective only in the specific instance and for
the specific purpose for which given.

         Section 13.23 Service of Process. Each of the Loan Parties irrevocably
consents to the service of process by the mailing thereof by the Administrative
Agent or the Required Lenders by registered or certified mail, postage prepaid,
to such Loan Party at its address listed on the signature pages hereof. Nothing
in this Section 13.23 shall affect the right of the Administrative Agent or the
Lenders to serve legal process in any other manner permitted by law or affect
the right of the Administrative Agent or any Lender to bring any action or
proceeding against such Loan Party or its Property in the court of any
jurisdiction.

         Section 13.24 Reaffirmation of Supply Agreement. Each of the Borrower,
the Operating Subsidiaries and Nortel Networks hereby reaffirms, ratifies and
confirms all of its indebtedness, liabilities and obligations under the Supply
Agreement as if the Supply Agreement were executed and delivered by the
Borrower, the Operating Subsidiaries and Nortel Networks as of the Closing
Date.

         Section 13.25 Amendment and Restatement of the Original Credit
Agreement. Effective as of the Closing Date, this Agreement shall constitute an
amendment and restatement of all, but not an extinguishment, discharge,
satisfaction or novation of any, indebtedness liabilities and/or obligations
(including, without limitation, the Obligations) of the Loan Parties under the
Original Credit Agreement.

         Section 13.26 Assignments of Original Loans. The Lenders hereby agree
among themselves (and the Borrower and each of the other Loan Parties hereby
consents to such agreement) that, immediately prior to but substantially
concurrently with the Closing Date, there shall be deemed to have occurred
assignments with respect to the outstanding Original Tranche A Loans, Original
Tranche B Loans and Original Tranche C Loans such that, after giving effect to
such assignments, the outstanding Tranche A Loans, Tranche B Loans and Tranche
C Loans is as stated in Section 2.1 and that, as of the Closing Date, each of
the Lenders is the holder of such Tranche A Loans, Tranche B Loans and Tranche
C Loans in an amount equal to the product of its Commitment Percentage of the
Tranche A Commitments, the Tranche B Commitments and the Tranche C Commitments,
respectively, multiplied by the principal amount of the Tranche A Loans,
Tranche B Loans and Tranche C Loans, respectively, outstanding as of the
Closing Date.

         Section 13.27 No Requirement of Assumption or Payment of Another
Person's Debt. Each of the Loan Parties acknowledges and agrees that neither
the Administrative Agent nor any Lender

CREDIT AGREEMENT - Page 108

<PAGE>   116

has required, as a condition to the Loans made or to be made under this
Agreement, that the Borrower or any other Loan Party assume or agree to pay any
Debt of another Person.

           [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK.]

CREDIT AGREEMENT - Page 109

<PAGE>   117

         IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as of the day and year first above written.

                               ALAMOSA PCS, INC.

                               By:     /S/ DAVID E. SHARBUTT
                                       ------------------------------
                               Name:   David E. Sharbutt
                               Title:  President

                               Address for Notices:
                               -------------------
                               200 West Ninth Street Plaza, Suite 102
                               Wilmington, Delaware  19801
                               Attention:        President
                               Telecopy No.:     (302) 658-0468
                               Telephone No.:    (302) 573-3899

CREDIT AGREEMENT - Page 110

<PAGE>   118

                                         ALAMOSA PCS HOLDINGS, INC.

                                         By:     /S/ DAVID E. SHARBUTT
                                                 ------------------------------
                                         Name:   David E. Sharbutt
                                         Title:  Chairman of the Board

                                         Address for Notices:
                                         -------------------
                                         4403 Brownfield Highway
                                         Lubbock, Texas  79407
                                         Attention:       Chairman of the Board
                                         Telecopy No.:    (806) 722-1120
                                         Telephone No.:   (806) 722-1111

CREDIT AGREEMENT - Page 111

<PAGE>   119

                                   TEXAS TELECOMMUNICATIONS, LP

                                   By:     Alamosa Delaware GP, LLC
                                   Title:  General Partner

                                           By: /S/ DAVID E. SHARBUTT
                                               ---------------------------
                                           Name:    David E. Sharbutt
                                           Title:   Manager and President

                                   Address for Notices:
                                   -------------------
                                   4403 Brownfield Highway
                                   Lubbock, Texas  79407
                                   Attention:         President
                                   Telecopy No.:      (806) 722-1120
                                   Telephone No.:     (806) 722-1111

CREDIT AGREEMENT - Page 112

<PAGE>   120

                            ALAMOSA WISCONSIN LIMITED PARTNERSHIP

                            By:     Alamosa Wisconsin GP, LLC
                            Title:  General Partner

                                    By:  /S/ DAVID E. SHARBUTT
                                         ---------------------------
                                    Name:    David E. Sharbutt
                                    Title:   Manager and President

                            Address for Notices:
                            -------------------
                            4403 Brownfield Highway
                            Lubbock, Texas  79407
                            Attention:      President
                            Telecopy No.:   (806) 722-1120
                            Telephone No.:  (806) 722-1111

CREDIT AGREEMENT - Page 113

<PAGE>   121

                         ADMINISTRATIVE AGENT:

                         NORTEL NETWORKS INC.,
                         as Administrative Agent

                         By:     /S/ ROBERT D. BEITER
                                 ---------------------------------------
                         Name:   Robert D. Beiter
                         Title:  Director, Customer Finance North America

                         Address for Notices:
                         -------------------
                         Nortel Networks Inc.
                         GMS 991 15 A40
                         2221 Lakeside Blvd.
                         Richardson, Texas 75082-4399
                         Attention: Robert D. Beiter
                                    Director, Customer Finance North America
                         Telecopy No.:      (972) 684-3679
                         Telephone No.:     (972) 685-1525

                         and

                         Nortel Networks Inc.
                         P.O. Box 833858
                         Richardson, Texas 75083-3858
                         Mail Stop 468/05/B40
                         2100 Lakeside Blvd.
                         Attention:     Kimberly Poe, Loan Administration
                         Telecopy No.:  (972) 685-3255
                         Telephone No.: (972) 684-7687

CREDIT AGREEMENT - Page 114

<PAGE>   122

                                           LENDERS:

                                           NORTEL NETWORKS INC.

Tranche A Commitment:   $167,000,000

Tranche B Commitment:   $  58,000,000      By:    /S/ ROBERT D. BEITER
                                                  --------------------------
                                           Name:  Robert D. Beiter
Tranche C Commitment:   $  25,000,000      Title: Director, Customer Finance
                        -------------             North America

                                           Address for Notices:
Total Commitments:      $ 250,000,000      Nortel Networks Inc.
                        =============      GMS 991 15 A40
                                           2221 Lakeside Blvd.
                                           Richardson, Texas 75082-4399
                                           Attention:   Robert D. Beiter
                                                        Director, Customer
                                                        Finance North  America
                                           Telecopy No.:     (972) 684-3679
                                           Telephone No.:    (972) 685-1525

                                           and

                                           Nortel Networks Inc.
                                           P.O. Box 833858
                                           Richardson, Texas 75083-3858
                                           Mail Stop 468/05/B40
                                           2100 Lakeside Blvd.
                                           Attention:  Kimberly Poe,
                                                       Loan Administration
                                           Telecopy No.:   (972) 685-3255
                                           Telephone No.:  (972) 684-7687

                                           Lending Office for Base Rate Loans:
                                           ----------------------------------
                                           Nortel Networks Inc.
                                           2221 Lakeside Blvd.
                                           Richardson, Texas 75082

                                           Lending Office for Eurodollar Loans:
                                           -----------------------------------
                                           Nortel Networks Inc.
                                           2221 Lakeside Blvd.
                                           Richardson, Texas 75082

CREDIT AGREEMENT - Page 115<PAGE>   1
                                                                   EXHIBIT 10.20

                                 AMENDMENT NO. 4
                                       TO
                        DMS-MTX CELLULAR SUPPLY AGREEMENT
                                     BETWEEN
                                 ALAMOSA PCS LLC
                                       AND
                              NORTEL NETWORKS INC.

        This Amendment No. 4 is made effective as of the 8th day of February,
2000, by and between Nortel Networks Inc. (successor in interest to Northern
Telecom Inc.) ("Seller") and Alamosa PCS LLC ("Buyer").

        WHEREAS, Buyer and Seller entered into a Supply Agreement dated December
21, 1998, as amended, for the sale and purchase of Seller's Equipment and
Services ("Agreement"); and

        WHEREAS, Buyer and Seller now wish to, among other things, amend the
Agreement to extend the Term and adjust Buyer's Volume Commitment; and

        NOW, THEREFORE, in consideration of the mutual covenants herein
contained, Buyer and Seller hereby agree to amend the Agreement as follows:

        1.  Amend Article 1 (Definitions), Section 1.46 by deleting the phrase
            "three years therefrom" and replacing it with "on July 1, 2002."

        2.  Amend Section 5.3 by deleting the reference to "eighty-two million
            dollars ($82,000,000) and replacing it with "one hundred sixty-seven
            million dollars ($167,000,000)."

        3.  Amend Section 5.4 by deleting the section in its entirety and
            replacing it with the following:

            "5.4  Until Buyer's total purchases under this Agreement exceed
                  eighty-two million dollars ($82,000,000) net Price in
                  Equipment and Services, such Equipment and Services purchased
                  and financed by Seller shall be subject to an additional three
                  percent (3%) financing premium ("Financing Premium") over the
                  Additional Affiliate pricing as set forth in Annex 1. For
                  subsequent purchases (i.e., purchases of Equipment and
                  Services in excess of eighty-two million dollars [$82,000,000]
                  net Price), such Financing Premium shall no longer apply."

        4.  Except as specifically modified herein, the Agreement in all other
            respects shall continue in full force and effect.

<PAGE>   2

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 4
to be executed by their representatives being thereunto duly authorized.

ALAMOSA PCS LLC                              NORTEL NETWORKS INC.

By:      /s/ DAVID SHARBUTT                  By:      /s/ ROBERT D. BEITER
   --------------------------------             --------------------------------
Name:    David Sharbutt
     ------------------------------          Name:    Robert D. Beiter
               (Type/Print)                       ------------------------------
                                                            (Type/Print)
Title:   Chief Executive Officer
      -----------------------------          Title:   Director, Customer Finance
Date:    February 8, 2000                          -----------------------------
     ------------------------------          Date:    February 8, 2000
                                                  ------------------------------

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