Document:

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                                                                   EXHIBIT 10.44

                       SUBSCRIBER UNIT PURCHASE AGREEMENT
                            FOR NEXTEL DEL PERU, S.A.

            This Agreement is entered into between Motorola, Inc., by and
through its iDEN Subscriber Group, having a place of business at 8000 West
Sunrise Boulevard; Ft. Lauderdale, Florida 33322 (hereinafter "Seller" or
"MOTOROLA") and Nextel del Peru, S.A., a company formed under the laws of Peru,
with a place of business at Calle Chinchon 1018, Piso 7, Lima 27 Peru
(hereinafter, together with any wholly-owned subsidiary previously accepted by
the Seller, collectively known as "Buyer").

            This agreement applies only for sales of Motorola iDEN subscriber
products for distribution outside of the United States. Buyer agrees to purchase
and Seller agrees to sell selected Motorola iDEN subscriber products
manufactured in Seller's facilities in Plantation, Florida, U.S.A., (hereinafter
"Products") during a term beginning on the date of the last signature hereto
("Effective Date"), and ending April 30, 2000 ("Initial Term"), under the terms
and conditions set forth in this Agreement. Buyer may purchase products
manufactured at Seller's other facilities under terms and conditions acceptable
to both parties at the time such purchases are desired.

PURCHASE ORDERS. All orders by Buyer shall be only upon the terms and conditions
of this Agreement. The only effect of any terms and conditions in Buyer's orders
or elsewhere shall be to request the time and number of units to be delivered,
subject to Seller's acceptance, but they shall not change, alter or add to the
terms and conditions of this Agreement in any other way. Except as provided
below, Seller's invoice shall also not change the terms and conditions of this
Agreement. Cancellation charges which shall include all costs incurred or
committed for may apply for any cancelled order. Seller shall use its reasonable
best efforts, including shipment to other Nextel properties, to mitigate any
costs incurred as a result of the Buyer's cancellation of an order within the
non-cancelable period. Purchase orders are non-cancelable fifteen (15) days or
less before requested ship date.

PRICING. Contract prices for Products require firm and prosecutable orders
thirty (30) days prior to requested ship date. Prices applicable to Products
sold pursuant to this Agreement ("Prices") are those negotiated from time to
time by Nextel Communications, Inc. and Motorola, Inc. In order for Prices to be
applicable, the purchase orders submitted to Seller must reference this
Agreement.

PAYMENT TERMS AND CONDITIONS. Seller will invoice Buyer for the Products on or
about the date of shipment thereof. Payment of each invoiced amount is due
within 30 days of the date of the invoice; [*]. The Buyer may prepay any
invoice, in part or in full, without penalty or premium at any time.

                                        1

     * Confidential portions omitted and filed separately with the Commission
pursuant to an application for confidential treatment pursuant to Rule 24b-2
under the Securities and Exchange Act of 1934, as amended.
<PAGE>   2
[*]

[*]

FORECASTS. During the term of this Agreement, Buyer shall provide Seller, [*] a
continuous usage forecast for [*] to assist Seller in maintaining an orderly
production flow for the purpose of Buyer's delivery requirements. Buyer shall
state in the [*] Forecast the Product model numbers and projected purchase
volume by units for [*]. The [*] Forecast does not constitute a commitment by
the Buyer; however, Buyer's failure to provide such information may be
considered cause by Seller for excusable delivery delay.

DELIVERY AND TITLE. All deliveries are FCA Seller's plant, Plantation, Florida
USA. Each such delivery will be separately invoiced. DELIVERY DATES ARE BEST
ESTIMATES ONLY. Title to the Products will pass to Buyer at the Seller's plant,
Plantation, Florida.

FORCE MAJEURE. Neither party shall be liable for any delay or failure to perform
due to any cause beyond its reasonable control. Causes include, but are not
limited to strikes, acts of God, acts of the other party, interruptions of
transportation or inability to obtain necessary labor, materials or facilities,
or default of any supplier, or delays in regulatory authorization or license
grant. The delivery schedule shall be considered extended by a period of time
equal to the time lost because of any excusable delay. In the event either party
is unable to wholly or partially perform for a period greater than forty-five
(45) days because of any cause beyond its reasonable control, either party may
terminate any delayed order without any liability.

LICENSE DISCLAIMER. Nothing contained herein shall be deemed to grant either
directly or by implication, estoppel, or otherwise, any license under any
patents, copyrights, trademarks or trade secrets of SELLER.

TAXES. Except for the amount, if any, of specific taxes stated in the Agreement,
Prices are exclusive of any amount for Federal, State and/or Local excise,
sales, use, property, retailer's, occupation or any other assessment in the
nature of taxes however designated, on the Products and/or services provided
under this Agreement. If any such excluded tax, exclusive however, of any taxes
measured by Seller's net income or taxes based on Seller's gross receipts or
based on Seller's franchise, is determined to be applicable to this transaction
or to the extent Seller is required to pay or bear the burden thereof, one
hundred percent (100%) thereof shall be added to the Prices and paid by Buyer.
Personal property taxes assessed on the Products after the date title transfers
under this paragraph, shall be the responsibility of Buyer. In the event Buyer
claims exemption from sales, use or other such taxes under this Agreement, Buyer
shall hold Seller harmless of any subsequent assessments levied by a proper
taxing authority for such taxes, including interest, penalties, and late
charges.

Upon Seller's request, Buyer shall produce sufficient evidence within thirty
(30) days of such request to prove that Buyer has fulfilled its obligation
relating to all taxes, duties, and fees. If any such taxes, duties, or fees are
determined to be applicable to this transaction and notwithstanding Buyer's
responsibility, Seller is required to pay or bear the burden thereof, then
Prices shall be increased by the amount of such taxes and any interest or
penalty, and Buyer shall pay to Seller the full amount of any such increase no
later than thirty (30) days after receipt of an invoice.

Customs clearance, or related costs pertaining to import of the Products are the
responsibility of Buyer. No such costs have been included in Seller's Prices.

                                        2

     * Confidential portions omitted and filed separately with the Commission
pursuant to an application for confidential treatment pursuant to Rule 24b-2
under the Securities and Exchange Act of 1934, as amended.

<PAGE>   3

TECHNICAL ASSISTANCE. Seller's warranty shall not be enlarged, and no obligation
or liability shall arise out of Seller's rendering of technical advice,
facilities or service in connection with Buyer's purchase of the Products
furnished.

LIMITATION OF LIABILITY. SELLER'S TOTAL LIABILITY, WHETHER FOR BREACH OF
CONTRACT, WARRANTY, NEGLIGENCE, STRICT LIABILITY IN TORT OR OTHERWISE, IS
LIMITED TO THE PRICE OF THE PARTICULAR PRODUCTS SOLD HEREUNDER WITH RESPECT TO
WHICH LOSSES OR DAMAGES ARE CLAIMED. BUYER'S SOLE REMEDY IS TO REQUEST SELLER AT
SELLER'S OPTION TO EITHER REFUND THE PURCHASE PRICE, REPAIR OR REPLACE PRODUCT
(S) THAT ARE NOT AS WARRANTED. IN NO EVENT WILL SELLER BE LIABLE FOR ANY LOSS OF
USE, LOSS OF TIME, INCONVENIENCE, COMMERCIAL LOSS, LOST PROFITS OR SAVINGS OR
OTHER INCIDENTAL OR CONSEQUENTIAL DAMAGES TO THE FULL EXTENT SUCH MAY BE
DISCLAIMED BY LAW.

LOGOS AND TRADEMARKS. In order that Seller may protect its trademarks, trade
names, corporate slogans, corporate logo, goodwill and product designations,
Buyer, without the express written consent of Seller, shall have no right to use
any such marks, names, slogans or designations of Seller in the sales, lease or
advertising of any products or on any product container, component part,
business forms, sales, advertising and promotional materials or other business
supplies or material, whether in writing, orally or otherwise. Buyer agrees to
provide Motorola with advertising material containing any Motorola marks for
approval before such marks are used. Motorola agrees to review Buyer's
advertising material in a reasonable time and to not unreasonably withhold
approval thereof. To minimize the impact of this review on the Buyer, Motorola
will provide Buyer with guidelines on the use of Motorola logos. Compliance with
these guidelines shall serve to relieve Buyer from having to submit
advertisements for prior approval.

PARTY RELATIONSHIP. This Agreement does not create any agency, joint venture or
partnership between Buyer and Seller. Buyer shall not impose or create any
obligation or responsibility, express or implied, or make any promises,
representations or warranties on behalf of Seller, other than as expressly
provided herein.

WAIVER. The failure of either party to insist in any one or more instances, upon
the performance of any of the terms or conditions herein or to exercise any
right hereunder shall not be construed as a waiver or relinquishment of the
future performance of any such terms or conditions or the future exercise of
such right but the obligation of the other party with respect to such future
performance shall continue in full force and effect.

DEFAULT. In the event that either party shall be in breach or default of any of
the terms or conditions of this Agreement and such breach or default shall
continue for a period of thirty (30) days after the giving of written notice by
the non-defaulting party, then subject to the other terms and conditions of this
Agreement, the non-defaulting party, in addition to other rights and remedies it
may have in law or equity, shall have the right to immediately cancel this
Agreement without any charge or liability whatsoever.

DISPUTE RESOLUTION. The parties agree that any claims or disputes will be
submitted to non-binding mediation prior to initiation of any formal legal
process. Costs of mediation will be shared equally.

WARRANTY. The warranty document supplied with the Product at the time of
shipping shall govern the warranty coverage provided under this Agreement.

GENERAL. This Agreement constitutes the entire and final expression of agreement
between the parties pertaining to the subject matter hereof and supersedes all
other communications, oral or written, between the parties. No alterations or
modifications of this Agreement shall be binding upon either Buyer or Seller
unless made in writing and signed by an authorized representative of each. If
any term or condition of this

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Agreement shall to any extent be held by a court or other tribunal to be
invalid, void or unenforceable, then that term or condition shall be inoperative
and void insofar as it is in conflict with law, but the remaining rights and
obligations of the parties shall be construed and enforced as if this Agreement
did not contain the particular term or condition held to be invalid, void or
unenforceable. Buyer shall make no assignment of this Agreement or of any right
granted herewith without the prior written consent of SELLER. Any assignment of
this Agreement is null and void. The laws of the State of Illinois of the United
States shall govern this Agreement.

            Unless this Agreement is superseded by a new agreement, or otherwise
terminated pursuant to the terms contained herein, this Agreement will continue
in effect beyond its Initial Term until terminated by either party upon thirty
(30) days prior written notice.

            IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed by their duly authorized representatives effective as of the 23 day of
July, 1999.

       SELLER:                                         BUYER:

       MOTOROLA, INC.                                  NEXTEL DEL PERU, S.A.

By:    /s/ Mark Shockley                            By: /s/ W.R. Hinchcliff
       -------------------------------------           ------------------------
       Signature                                       Signature

Printed Name: MARK SHOCKLEY                        Printed Name: W.R. Hinchcliff
                                                                ----------------

Title: Vice President & General Manager            Title: President
       iDEN International Markets Division               ----------------------
       iDEN Subscriber Group

Date: July 23, 1999                                Date: July 23, 1999
     ---------------------------------------            -----------------------

                                        4<PAGE>   1
                                                                   EXHIBIT 10.45

                                 THIRD AMENDMENT
                                       TO
                          EQUIPMENT FINANCING AGREEMENT

       This Third Amendment (the "Third Amendment") to Equipment Financing
Agreement is entered into by and between MCCAW INTERNATIONAL (BRAZIL), LTD., a
corporation organized under the laws of the State of Virginia, with its
principal office at 2001 Edmund Halley Drive, Reston, Virginia, 20191 U.S.A.
(the "Company") and MOTOROLA CREDIT CORPORATION, a corporation duly organized
under the laws of the State of Delaware, U.S.A., with its principal office at
1303 East Algonquin Road, Schaumburg, Illinois 60196-1065, U.S.A. (the
"Creditor").

                              W I T N E S S E T H:

       WHEREAS, the Company has heretofore entered into an Equipment Financing
Agreement, dated as of October 31, 1997 with the Creditor (as heretofore
amended, modified or supplemented, the "Financing Agreement"; capitalized terms
used herein and not otherwise defined herein having the meanings assigned
thereto in the Financing Agreement);

       WHEREAS, the Company has requested that the Creditor agree to certain
amendments to the Financing Agreement; and

       WHEREAS, subject to the terms and conditions set forth herein, the
Creditor is willing to undertake certain amendments to the Financing Agreement.

       NOW, THEREFORE, in consideration of the premises, and intending to be
legally bound hereby, the Company and the Creditor hereby agree as follows:

       SECTION 1. AMENDMENTS.

       Upon the satisfaction by the Company of the conditions precedent set
forth in Section 2 below, and in reliance on the warranties of the Company set
forth in Section 3 below, the Financing Agreement is hereby amended as follows:

       1.1    There is hereby added to the Schedules to the Financing Agreement
              (a) a Schedule 1.01(c) ("Target Subscribers") and (b) Schedule
              1.01(d) ("Adjusted Paid-in Capital Schedule") in the forms
              attached.

       1.2    The following term is hereby added to Section 1.01 of the
              Financing Agreement in its appropriate alphabetical order:

                                       -1-

<PAGE>   2

              " "Adjusted Consolidated Fixed Charges" means, as to any Person
              and for any period, without duplication, the difference of (a) the
              sum of the following: (i) the total interest expense for such
              Person and its Subsidiaries on a consolidated basis for such
              period (including, without limitation, all interest expense on
              Capital Lease Obligations), (ii) the scheduled principal amount of
              all amortization payments on all Indebtedness for borrowed money
              of such Person and its Subsidiaries on a consolidated basis for
              such period, other than payments in respect of Permitted
              Indebtedness of the type described in clause (b) of the definition
              thereof for such period which arise from handset purchases and
              which are owed to a Motorola Entity, (iii) all payments made under
              capitalized leases (except for any such payments covered by clause
              (i) of this definition), and (iv) all payments made under Hedge
              Agreements, minus (b) all payments received under Hedge
              Agreements."

       1.3    The following term is hereby added to Section 1.01 of the
              Financing Agreement in its appropriate alphabetical order:

              " "Adjusted Paid-in Capital" means, as of any date, (a) the
              paid-in capital of the Company (including for this purpose the
              principal amount of any outstanding Permitted Indebtedness
              incurred by the Company of the type described under clause (l) of
              the definition thereof) reflected on the most recent financial
              statements delivered pursuant to Section 8.2 or 8.3 (whichever is
              later) plus (b) any increases in paid-in capital (including for
              this purpose the principal amount of any outstanding Permitted
              Indebtedness incurred by the Company and of the type described
              under clause (l) of the definition thereof) since the end of the
              reporting period relating to such financial statements minus (c)
              any decreases in paid-in capital (including any repayments,
              whether or not permitted hereunder, of any principal or interest
              with respect to Permitted Indebtedness of the type described under
              clause (l) of the definition thereof) since the end of the
              reporting period relating to such financial statements. "

       1.4    The following term is hereby added to Section 1.01 of the
              Financing Agreement in its appropriate alphabetical order:

              " "Quarterly Paid-in Capital Contribution" shall mean, for any
              quarter, the net increase in cumulative Adjusted Paid-in Capital
              from the beginning of such quarter to the end of such quarter, as
              determined in accordance with the calculation of "Ending
              Cumulative Paid In Capital - Actual" as set forth on Schedule
              1.01(c) hereto."

       1.5    The following term is hereby added to Section 1.01 of the
              Financing Agreement in its appropriate alphabetical order:

                                       -2-

<PAGE>   3

              " "Target Subscribers" means, as of any quarter end date, the
              "Target Subscribers" set forth opposite such quarter end date on
              Schedule 1.01(d) hereto."

       1.6    The definition of the term "Fixed Charge Coverage Ratio" set forth
              in Section 1.01 of the Financing Agreement is hereby amended and
              restated as follows:

              " "Fixed Charge Coverage Ratio" means, as at any date, the ratio
              (for the then ending or most recently ended fiscal quarter of the
              Company) of (a) (i) EBITDA for such quarter plus (ii) the
              Quarterly Paid-in Capital Contribution for such quarter (plus the
              decrease (or minus the increase) in the value added tax credit
              account during such quarter) to (b) Adjusted Consolidated Fixed
              Charges for such quarter."

       1.7    The definition of the term "Permitted Indebtedness" set forth in
              Section 1.01 of the Financing Agreement is hereby amended and
              restated as follows:

              " "Permitted Indebtedness" means, collectively, (a) the
              Obligations, (b) trade accounts payable and other similar
              Indebtedness of the Company and the Foreign Affiliates incurred in
              the ordinary course of business (including, without limitation,
              handsets or mobile units purchased in the ordinary course of
              business) which are not due later than 120 days after invoice (or,
              in the case of trade accounts payable owed to a Motorola Entity,
              on payment and other terms as agreed to from time to time between
              the relevant obligor(s) and the Motorola Entity); provided that in
              addition to the foregoing, there shall be permitted to be
              outstanding at any one time trade accounts payable and other
              similar Indebtedness of the Company and the Foreign Affiliates
              incurred in the ordinary course of business which are due later
              than 120 days after invoice but no later than 180 days after
              invoice (not to exceed the difference between $10,000,000 and the
              amount of "Permitted Indebtedness" under and as defined in the
              MEFA above $10,000,000 that has been utilized under clause (b) of
              the definition thereof), (c) obligations under long-term real
              property leases of the Company and the Foreign Affiliates in
              respect of the cell sites, switch sites, retail space and office
              space incurred in the ordinary course of business, (d) short-term
              lease obligations of the Company and the Foreign Affiliates in an
              amount per annum not exceeding $250,000 in the aggregate, (e)
              Indebtedness of the Company and the Foreign Affiliates to be used
              for working capital purposes and not exceeding $7,000,000 in the
              aggregate which may be secured by the Collateral on a pari passu
              basis on terms and conditions reasonably satisfactory to the
              Creditor, (f) Indebtedness of the Company and the Foreign
              Affiliates not exceeding $50,000,000 in the aggregate which may be

                                       -3-

<PAGE>   4

              secured by the Collateral on a pari passu basis on terms and
              conditions reasonably satisfactory to the Creditor, (g)
              Indebtedness of Nextel S.A. to Motorola do Brasil relating to
              loans made by Motorola do Brasil as the minority shareholder in
              Nextel S.A. pursuant to subsection 5.2(e) of the Nextel S.A.
              Shareholders Agreement, (h) Indebtedness of the Company to Nextel
              International incurred in order to fund prepayment obligations as
              described in subsection 2.05(e) hereof, (i) Indebtedness of the
              Company to Motorola Credit Corporation, a Delaware corporation,
              under the Bridge Line, (j) handset purchase financing from a
              financial institution in an amount not to exceed $60,000,000 in
              the aggregate, (k) Indebtedness under Hedge Agreements; provided
              that such Hedge Agreements (I) are designed solely to protect the
              Company against fluctuations in foreign currency exchange rates or
              interest rates and (II) do not increase the Indebtedness of the
              obligor outstanding at any time other than as a result of
              fluctuations in foreign currency exchange rates or interest rates
              or by reason of fees, indemnities and compensation payable
              thereunder, and (l) unsecured subordinated indebtedness of the
              Company owing to Nextel International, having no principal
              payments, cash interest payments or fee payments permitted or
              scheduled prior to the repayment in full of the Obligations and in
              amounts and on other terms (including, without limitation, payment
              and remedies subordination terms) acceptable to the Creditor."

       1.8    The definition of the term "Subscriber" set forth in Section 1.01
              of the Financing Agreement is hereby amended and restated as
              follows:

              " "Subscriber" means, as at any date, the aggregate number of
              units employing iDEN based digital enhanced specialized mobile
              radio technology, subscribing to, and paying for, communications
              services provided by the Company or the Foreign Affiliates in
              connection with the System, excluding any such unit to the extent
              the accounts receivable generated by operation of such unit are
              more than ninety (90) days past due as of such date."

       1.9    The last sentence of clause (b) of Section 8.02 of the Financing
              Agreement is hereby amended and restated in its entirety as
              follows:

              "(b) The foregoing financial statements shall be accompanied by a
              certificate of the Company's or Nextel International's principal
              financial officer setting forth in reasonable detail each of the
              calculations required to establish compliance with the financial
              covenants set forth in Section 8.17 hereto, which certificate
              shall include a representation that each such calculation
              (including, without limitation, any such calculations made
              pursuant to any Schedule to this Agreement) (i) has been made in
              accordance with GAAP, (ii) is consistent with all relevant
              definitions set

                                       -4-

<PAGE>   5

              forth in this Agreement, and (iii) is consistent with the
              Company's preparation of the Approved Business Plan."

       1.10   The last sentence of clause (b) of Section 8.03 of the Financing
              Agreement is hereby amended and restated in its entirety as
              follows:

              "(b) The foregoing financial statements shall be accompanied by a
              certificate of the Company's or Nextel International's principal
              financial officer setting forth in reasonable detail each of the
              calculations required to establish compliance with the financial
              covenants set forth in Section 8.17 hereto, which certificate
              shall include a representation that each such calculation
              (including, without limitation, any such calculations made
              pursuant to any Schedule to this Agreement) (i) has been made in
              accordance with GAAP, (ii) is consistent with all relevant
              definitions set forth in this Agreement, and (iii) is consistent
              with the Company's preparation of the Approved Business Plan."

       1.11   Section 8.17 of the Financing Agreement is hereby amended and
              restated in its entirety as follows:

              " Section 8.17. Financial Covenants. The Company and its
       Subsidiaries shall have or maintain, on a consolidated basis, at all
       times:

              (a) a Fixed Charge Coverage Ratio (measured at the end of each
       fiscal quarter) of not less than 1.00 : 1.00 at the end of each fiscal
       quarter of the Company;

              (b) EBITDA, at the end of each fiscal quarter period then ended
       (measured at the end of each fiscal quarter), of not less than the
       respective amounts set forth opposite each such date:

                             Date                           EBITDA

                           March 31, 2000               $(21,500,000)
                            June 30, 2000               $(16,400,000)
                       September 30, 2000               $(19,300,000)
                        December 31, 2000               $(22,300,000)
                           March 31, 2001               $(11,800,000)
                            June 30, 2001                $(9,900,000)
                       September 30, 2001                $(6,300,000)
                        December 31, 2001                    $100,000
                           March 31, 2002                  $3,800,000
                            June 30, 2002                  $7,900,000
                       September 30, 2002                 $10,600,000

                                       -5-
<PAGE>   6

                        December 31, 2002                 $12,000,000
                           March 31, 2003                 $14,600,000
                            June 30, 2003                 $22,700,000
                       September 30, 2003                 $24,000,000
                        December 31, 2003                 $27,500,000

              (c) a ratio of Indebtedness to EBITDA as at the end of each
       quarterly period then ended of not greater than the ratios set forth
       opposite each such date:

                                Date                    Indebtedness to
                                                            EBITDA

                           March 31, 2002                 41.1 : 1.00
                            June 30, 2002                 17.3 : 1.00
                       September 30, 2002                 12.8 : 1.00
                        December 31, 2002                  9.8 : 1.00
                           March 31, 2003                  8.1 : 1.00
                            June 30, 2003                  4.3 : 1.00
                       September 30, 2003                  4.1 : 1.00
                        December 31, 2003                  2.9 : 1.00

              (d) minimum Recurring Revenues, as at the end of each quarterly
       period then ended, of not less than the respective amounts set forth
       opposite each such date:

            Date                                      Recurring Revenues

       March 31, 2000                                      $8,700,000
       June 30, 2000                                       $9,700,000
       September 30, 2000                                 $13,000,000
       December 31, 2000                                  $16,900,000
       March 31, 2001                                     $22,300,000
       June 30, 2001                                      $27,700,000
       September 30, 2001                                 $30,900,000
       December 31, 2001                                  $35,000,000
       March 31, 2002                                     $39,700,000
       June 30, 2002                                      $43,500,000
       September 30, 2002                                 $48,500,000
       December 31, 2002                                  $53,500,000
       March 31, 2003                                     $59,200,000
       June 30, 2003                                      $63,800,000
       September 30, 2003                                 $67,600,000

                                       -6-

<PAGE>   7

       December 31, 2003                                  $71,800,000

              (e) a minimum number of Subscribers, as at the end of each
       quarterly period then ended, of not less than the number of Subscribers
       set forth opposite each such date:

                               Date                         Subscribers

                           March 31, 2000                     115,000
                            June 30, 2000                     129,000
                       September 30, 2000                     154,000
                        December 31, 2000                     190,000
                           March 31, 2001                     226,000
                            June 30, 2001                     253,000
                       September 30, 2001                     280,000
                        December 31, 2001                     311,000
                           March 31, 2002                     345,000
                            June 30, 2002                     370,000
                       September 30, 2002                     398,000
                        December 31, 2002                     431,000
                           March 31, 2003                     468,000
                            June 30, 2003                     489,000
                       September 30, 2003                     513,000
                        December 31, 2003                     538,000

              (f) a minimum amount of Adjusted Paid-In Capital at all times for
       each calendar quarter in an amount equal to the actual cash requirements
       for such calendar quarter as provided in the Adjusted Paid-In Capital
       Schedule (in the form of Schedule 1.01(c) attached hereto) provided by
       the Company as part of the compliance package delivered with the
       financial statements required under Sections 8.2 and 8.3. As set forth in
       the Adjusted Paid-In Capital Schedule (Schedule 1.01(c)), a deficiency in
       Adjusted Paid-In Capital for any calendar quarter must be contributed
       into the Company within fifteen (15) days from the end of the applicable
       reporting period.

       Notwithstanding anything herein to the contrary (including, without
       limitation, the provisions of Section 11.1 hereof), (i) a breach of
       Section 8.17(d) hereof shall not constitute an Event of Default hereunder
       unless the Company is in breach of such Section 8.17(d) as of two (2)
       consecutive quarter end dates and (ii) a breach of Section 8.17(b) or
       Section 8.17(c) hereof as of any quarter end date shall not constitute an
       Event of Default hereunder unless the aggregate Subscribers as of the end
       of such quarter were less than the "Target Subscribers" set forth
       opposite the quarter end dates set forth in Schedule 1.01(d). "

                                       -7-

<PAGE>   8

       1.12 The parties agree and acknowledge that the address for notices for
the Company shall, until changed pursuant to Section 12.07 of the Financing
Agreement, be Nextel International, Inc., 10700 Parkridge Blvd., Suite 600,
Reston, Virginia 20191, Attention: Chief Financial Officer (Telecopy:
703-390-5111), with copies to (a) Nextel International, Inc., 2001 Edmund Halley
Drive, Reston, VA 20191, Attention: Legal Department (Telecopy: 703-433-4035)
and (b) Nextel S.A., Ave. Maria Coelho Aguiar-215, Bloco D - 7o Andar, 5808-900
Sao Paulo, SP, 5808-901 Brasil, Attention: Legal Department (Telecopy: 55 11
3748 1215).

       SECTION 2. CONDITIONS.

       (a) As a condition precedent to the effectiveness of the Third Amendment,
the Company shall have delivered to the Creditor the Third Amendment, duly
executed and delivered and appropriately dated and in form and substance
satisfactory to the Creditor, and such other documents as the Creditor may
reasonably request.

       (b) As a condition subsequent to the Third Amendment, the Company and the
Creditor shall have entered into an amended and restated Financing Agreement on
mutually acceptable terms no later than thirty (30) days from the date hereof.

       SECTION 3. REPRESENTATIONS AND WARRANTIES.

       To induce the Creditor to enter into the Third Amendment, the Company
hereby represents and warrants to the Creditor as of the date hereof that:

       (a) The representations and warranties contained in the Financing
       Agreement and the other Credit Documents are true and correct in all
       material respects on and as of November 30, 1999, except for
       representations and warranties that speak as of a particular date, in
       which case such representations and warranties are true as of such date;

       (b) With respect to the Company, there has been no Material Adverse
       Effect since November 30, 1999;

       (c) The consolidated audited balance sheets of the Company and its
       Subsidiaries and consolidated statements of operations, changes in
       stockholders' equity and cash flows of the Company and its Subsidiaries
       each as of December 31, 1998, and all other information and data
       heretofore furnished by the Company, or any agent of the Company on
       behalf of the Company to the Creditor, including, the quarterly (each as
       at March 31, 1999, June 30, 1999 and September 30, 1999) consolidated
       balance sheets and consolidated statements of operations, changes in
       stockholders' equity and cash flows, have been prepared in accordance
       with GAAP and fairly present the condition and

                                       -8-

<PAGE>   9

       results of operations of the Company and its Subsidiaries as of such
       dates or for such periods;

       (d) Each Credit Party has made all material required contributions under
       the Plans for all periods through and including September 30, 1999, or
       adequate accruals therefor have been provided for in the financial
       statements referenced in paragraph (b) above;

       (e) The actuarial value of vested benefits required to be funded by each
       Credit Party, or with respect to which such Credit Party is liable, under
       the Plans, determined using the actuarial methods and assumptions used by
       the relevant Plan's actuary as of the last valuation date for which an
       actuarial valuation was completed to determine such Plan's funded status,
       did not as of the last valuation date as of which an actuarial valuation
       has been completed, which in the case of any individual Plan was not
       earlier than January 1, 1999, exceed the actuarial value of the assets of
       the Plans allocable to such vested and non-vested benefits by a material
       amount; and

       (f) After giving effect to the Third Amendment, no Default or Event of
       Default has occurred and is continuing.

       SECTION 4. GENERAL.

       4.1 Reservation of Rights. The Company acknowledges and agrees that the
       execution and delivery of the Third Amendment shall not be deemed (i) to
       create a course of dealing or otherwise obligate the Creditor to forbear
       or execute similar amendments under the same or similar circumstances in
       the future, or (ii) as a waiver by the Creditor of any covenant,
       condition, term or provision of the Financing Agreement or any of the
       other Credit Documents, and the failure of the Creditor to require strict
       performance by the Company or any other Credit Party of any provision
       thereof shall not waive, affect or diminish any right of the Creditor to
       thereafter demand strict compliance therewith. The Creditor hereby
       reserves all rights granted under the Financing Agreement, the other
       Credit Documents and the Third Amendment.

       4.2 Full Force and Effect. As hereby modified, the Financing Agreement
       and each of the other Credit Documents shall remain in full force and
       effect and each is hereby ratified, approved and confirmed in all
       respects.

       4.3 Affirmation. The Company hereby affirms its obligations under Section
       4 of the Financing Agreement and agrees to pay on demand all reasonable
       costs and expenses of the Creditor in connection with the preparation,
       execution and delivery of the Third Amendment and all instruments and
       documents delivered in connection herewith.

                                       -9-

<PAGE>   10

       4.4 Successors and Assigns. The Third Amendment shall be binding upon and
       shall inure to the benefit of the Company, the Creditor and the
       respective successors and assigns of the Company and the Creditor.

       4.5 Counterparts. The Third Amendment may be executed in any number of
       counterparts and by the different parties on separate counterparts, and
       each such counterpart shall be deemed to be an original, but all such
       counterparts shall together constitute but one and the same Third
       Amendment.

                                    * * * * *

                                      -10-

<PAGE>   11

            IN WITNESS WHEREOF, the Company and the Creditor have executed this
Third Amendment as of the 24th day of March, 2000.

                                         COMPANY:

                                         MCCAW INTERNATIONAL (BRAZIL), LTD.

                                         By: /s/ Byron Siliezar
                                            --------------------------------
                                         Name: Byron Siliezar
                                              ------------------------------
                                         Title: Vice President and Treasurer
                                               -----------------------------

                                         CREDITOR:

                                         MOTOROLA CREDIT CORPORATION

                                         By: /s/ Gary Tatje
                                            --------------------------------
                                         Name: Gary Tatje
                                              ------------------------------
                                         Title: Vice President
                                               -----------------------------

                                      -11-
<PAGE>   12
                               SCHEDULE 1.01(c)
                      "ADJUSTED PAID-IN CAPITAL SCHEDULE"

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------------------
        PERIOD:                                                  FIRST QUARTER ENDING
                                                                      3/31/2000
-----------------------------------------------------------------====================--------------------------------------

-----------------------------------------------------------------====================--------------------------------------

-----------------------------------------------------------------====================--------------------------------------
                                                                  CUMULATIVE TOTALS

-----------------------------------------------------------------====================--------------------------------------
<S>                                                                     <C>              <C>
BEGINNING CUMULATIVE ADJUSTED PAID IN                                               0      A
CAPITAL- ACTUAL
---------------------------------------------------------------------------------------------------------------------------
BEGINNING CUMULATIVE ADJUSTED PAID IN                                               0      B
CAPITAL- REQUIRED
---------------------------------------------------------------------------------------------------------------------------
ONE-TIME CREDIT FOR DECEMBER 1999 CAPITAL                                 $16,729,764      Q
CONTRIBUTION MCCAW BRAZIL
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
                                                                                               TOTAL CONSOLIDATED PAID-
                                                                                                IN CAPITAL REQUIREMENT
===========================================================================================================================
Quarterly EBITDA Loss/(Gain)
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
plus/(minus): Capital expenditures/(sale of
assets)
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
plus/(minus): Interest expense, scheduled debt
amortizations, withholding tax on interest
expense, (interest income):
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
plus/(minus): increases/(decreases) in accounts
receivable, inventory, other non-cash current
assets:
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
minus/(plus): increases/(decreases) in accounts
payable, accrued expenses and other current
liabilities (except short-term notes payable):
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
plus/(minus): increases/(decreases) in the
Company's value added tax credit account
during such quarter:
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
minus: increases in short-term and long-term
debt and notes payable (except shareholder
notes as per Permitted Indebtedness (l)):
---------------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------
plus: increases/(decreases) in investments or
other assets (including spectrum and/or other
acquisitions and not including changes in the
Company's value added tax credit account
during such quarter)
---------------------------------------------------------------------------------------------------------------------------
</TABLE>

                                      -12-

<PAGE>   13

<TABLE>
------------------------------------------------------------------------------------------------------------------------------
<S>                                                     <C>                      <C>     <C>
------------------------------------------------------------------------------------------------------------------------------
minus: minority partner capital contributions(1):
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
TOTAL QUARTERLY PAID-IN CAPITAL                                                     0     C
CONTRIBUTION REQUIREMENT
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
ACTUAL QUARTERLY PAID-IN CAPITAL                                                          D
CONTRIBUTION
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
CUMULATIVE ADJUSTED PAID IN CAPITAL-                                                      A + D = X
ACTUAL
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
CUMULATIVE ADJUSTED PAID IN CAPITAL-                                                      B + C = Y
REQUIRED
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
DEFICIENCY IN PAID-IN CAPITAL TO BE                                                       If Y > X,  then Y - X, if not 0: Z
CONTRIBUTED:
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
ENDING CUMULATIVE ADJUSTED PAID IN                      0
CAPITAL- ACTUAL                                                                                X + Z
------------------------------------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------------------------------------
ENDING CUMULATIVE ADJUSTED PAID IN                      0                                          y
CAPITAL- REQUIRED
------------------------------------------------------------------------------------------------------------------------------
* Deficiencies in Paid-in Capital must be contributed into the Company within 15 days from the end of the reporting period.
------------------------------------------------------------------------------------------------------------------------------
</TABLE>

Note:   All calculations in the foregoing chart shall be made in accordance
with GAAP (unless non-GAAP variations are specified) and the application of
GAAP by the Company shall be on a consistent basis.

----------------
(1) This item is applicable ONLY IF there has been one hundred percent (100%)
consolidation by the Company with the entity to which the capital contribution
has been made.

                                     -13-

<PAGE>   14

                               SCHEDULE 1.01(d)
                             "TARGET SUBSCRIBERS"

                                                    Target
            Date                                 Subscribers

        March 31, 2000                             143,559
        June 30, 2000                              171,135
        September 30, 2000                         210,987
        December 31, 2000                          251,624
        March 31, 2001                             280,864
        June 30, 2001                              311,575
        September 30, 2001                         345,661
        December 31, 2001                          383,031
        March 31, 2002                             411,292
        June 30, 2002                              442,130
        September 30, 2002                         479,418
        December 31, 2002                          520,497
        March 31, 2003                             543,421
        June 30, 2003                              569,974
        September 30, 2003                         598,256
        December 31, 2003                          628,283

                                      -14-

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00006-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00006-of-00352.parquet"}]]