Document:

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                                                                Exhibit 10(x)(1)

                                FIRST AMENDMENT
                                       TO
                             OGLEBAY NORTON COMPANY
                           CAPITAL ACCUMULATION PLAN

          WHEREAS, the Oglebay Norton Company Capital Accumulation Plan was
established effective as of January 1, 2000; and

          WHEREAS, it is desired to amend the Plan for the purpose of modifying
provisions relating to deferral elections and for other purposes;

          NOW, THEREFORE, the Plan is hereby amended, effective as of January 1,
2001, in the respects hereinafter set forth.

          1.  Section 3.01(b) of the Plan is amended and restated to provide as
follows:

          b)  Acknowledgment of Eligibility and Election to Participate.  Each
              ---------------------------------------------------------
              eligible employee shall acknowledge his or her eligibility to
              participate in the Plan at such time and in such form as the
              Committee may require or permit. An eligible employee may elect to
              become a Participant with respect to a Plan Year and subsequent
              Plan Years by filing a properly completed Agreement with the
              Committee no later than December 1st ( or such other date not
              later than December 31st as the Committee may permit) of the
              calendar year preceding such initial Plan Year. An eligible
              employee shall become a Participant with respect to a Plan Year
              and subsequent Plan Years upon acceptance of his or her Agreement
              by the Committee. An Agreement, once accepted by the Committee,
              shall be irrevocable with respect to any Plan Year after such Plan
              Year has begun, but may be revoked or modified by December 1st (or
              other such other date not later than December 31st as the
              Committee may permit) of the calendar year preceding the Plan Year
              in which the Participant desires a new Agreement to take effect or
              desires to revoke his Agreement.

          2.  Section 3.02 of the Plan is amended and restated to provide as
follows:
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          3.02  Deferral of Salary, Bonus, and/or LTIP Payment.  A Participant
                ----------------------------------------------
                may elect to defer between zero percent (0%) and fifty percent
                (50%) of his or her Salary in ten percent (10%) increments
                during a Plan Year. In addition, a Participant may elect to
                defer between zero percent (0%) and one hundred percent (100%)
                of his or her Bonus payable during a Plan Year in ten percent
                (10%) increments. In addition, a Participant may elect to defer
                between zero percent (0%) and one hundred percent (100%) of his
                or her LTIP Payment payable during a Plan Year in ten percent
                (10%) increments. At the time of election, a Participant may
                elect to defer a different percentage of his or her Salary,
                Bonus, and/or LTIP Payment for each Plan Year and may also elect
                not to defer any portion of his or her Salary, Bonus, and/or
                LTIP Payment in a Plan Year.

                A Participant may make an annual election for an upcoming Plan
                Year no more than once per Plan Year, and by December 1st (or
                other such other date not later than December 31st as the
                Committee may permit) of the year preceding the Plan Year for
                which the election is being made. If no such election is made by
                the Participant, the prior Plan Year's election will continue to
                be effective for the next Plan Year. Except as provided in
                Sections 4.04, 4.07 and 4.10, any election made by a Participant
                shall be irrevocable with respect to Salary, Bonus, and LTIP
                Payment applicable to the Plan Year. A Participant who does not
                file an Agreement for a Plan Year may file an Agreement for any
                subsequent Plan Year for which he or she is eligible to
                participate in the Plan.

          3.    Section 4.03 of the Plan is amended and restated to provide as
follows:

          4.03  Distribution on Termination of Service.  Upon the Termination of
                --------------------------------------
                Service of a Participant prior to his or her Retirement Date for
                reasons other than death or Disability, distribution of the
                Participant's Deferred Compensation Account shall be made as
                soon as practicable and in any event within ninety (90) days
                after such Termination of Service, in a single lump-sum,
                notwithstanding the provisions of Section 4.05. Upon a
                Termination of Service prior to his or her Retirement Date or
                death or Disability, the Participant shall immediately cease to
                be eligible for any other benefit provided under this Plan.
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          4.    Section 8.05 of the Plan is amended and restated to provide as
follows:

          8.05  Protective Provisions. In order to facilitate the payment of
                ---------------------
                benefits hereunder, each employee designated eligible to
                participate in the Plan, shall cooperate with the Company by
                furnishing any and all information requested by the Company,
                including taking such actions as may be reasonably requested by
                the Company. If an employee refuses to cooperate, he or she
                shall not become a Participant in the Plan and the Company shall
                have no further obligation to him or her under the Plan. In the
                event a Participant has a balance in his or her Deferred
                Compensation Account, the Participant or his or her Beneficiary
                shall receive a benefit equal to his or her Deferred
                Compensation Account determined pursuant to Section 3.08 and
                paid in accordance with Section 4.03.

                            *          *          *

          EXECUTED this ________ day of January, 2001.

                                        OGLEBAY NORTON COMPANY

                                        By: Ronald J. Compiseno
                                           --------------------------
                                        Title: Vice President, Human Resources<PAGE>   1
                                                                   EXHIBIT 10.48
                                    AGREEMENT

               This Agreement (this "AGREEMENT") is made this 7th day of
March, 2001, by and between Nextel Communications, Inc. ("PARENT") and Nextel
International, Inc. (the "COMPANY").

                                    RECITALS

               1. The Company is an indirect subsidiary of Parent.

               2. The Company intends to register shares of its Class A Common
Stock, par value $0.001 ("CLASS A COMMON STOCK"), for offer and sale to the
public (that sale, but not the overallotment option, the "IPO").

               3. Parent is willing to contribute capital, through a wholly
owned subsidiary of Parent, to the Company and to receive, among other things,
the Class B Common Stock, par value $0.001, of the Company (the "CLASS B COMMON
STOCK") in connection with the consummation of the IPO.

               4. In consideration for Parent's contribution of capital, the
Company has agreed to grant to Parent the right (which Parent may exercise
through or assign to one or more Affiliates of Parent as designated by Parent
from time to time in accordance with Section 4(c)) to maintain its ownership
interest in the Company as more fully described below.

                                    AGREEMENT

               The parties to this Agreement agree as follows:

        1.      ANTI-DILUTIVE RIGHTS. (a) From and after the Effective Date
(defined in Section 4(k)) until such time as all of the Class B Common Stock
owned by Parent has been converted into Class A Common Stock and Parent ceases
to own any Class B Common Stock, in the event of any proposed public or private
issuances (each a "PROPOSED ISSUANCE") of shares of (i) Class A Common Stock,
(ii) Class B Common Stock or (iii) any other capital stock of the Company or any
other security convertible into or exercisable or exchangeable (with or without
the payment of additional consideration) for Class A Common Stock, Class B
Common Stock or other capital stock of the Company (excluding issuances of
shares of Class A Common Stock upon conversion of Class B Common Stock) (any
such security a "DERIVATIVE SECURITY") (the securities of the Company referred
to in clauses (i), (ii) and (iii) being referred to herein as "CAPITAL STOCK"),
the Company shall send written notice thereof to Parent not less than forty-five
(45) days prior to such Proposed Issuance, which notice must set forth all
material terms of the Proposed Issuance including, without limitation, the
manner of sale, the per share sale price (the "SALE PRICE") and the amount and
type of any other consideration to be received by the Company.

        (b)     Parent will have the right, by sending irrevocable written
notice thereof to the Company within thirty (30) days after receipt of the
Company's notice, to purchase up to such

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number of shares of Capital Stock or Derivative Securities, subject to Section
3(b), as is necessary to maintain its Voting Power Ownership Percentage or its
Fully Diluted Ownership Percentage (whichever is greater) as they existed
immediately prior to such Proposed Issuance.

        (c)     Prices to Parent will be:

                (1)     If the Proposed Issuance is Capital Stock solely for
                        cash, then the Sale Price;

                (2)     If the Proposed Issuance is Capital Stock and is not for
                        cash, then at the average of the closing sales prices of
                        a share of Class A Common Stock as reported on the
                        Nasdaq National Market for the ten (10) trading day
                        period beginning on and including the eleventh Business
                        Day immediately preceding the Closing (defined in
                        Section 3(a)) and ending on and including the Business
                        Day immediately preceding the Closing as reported in The
                        Wall Street Journal (the "AVERAGE PRICE").

                (3)     If the Proposed Issuance involves only a Derivative
                        Security and the Derivative Security is bought solely
                        for cash, then the Sale Price;

                (4)     If the Proposed Issuance involves only Capital Stock
                        acquired upon exercise, exchange or conversion of a
                        Derivative Security, then the Average Price;

                (5)     If the Proposed Issuance involves a combination of
                        Capital Stock or other securities and Derivative
                        Securities (such combination a "UNIT") and such Unit is
                        sold solely for cash, then the Sale Price; and

                (6)     If the Proposed Issuance involves a Derivative Security
                        and/or a security that is either not Capital Stock or is
                        Capital Stock other than Class A Common Stock or Class B
                        Common Stock, and the sale thereof is not solely for
                        cash, then the cash price determined by the agreement of
                        the Company and Parent; and

                (7)     To the extent Parent has elected to acquire Derivative
                        Securities, any acquisition of shares of Capital Stock
                        upon exercise, exchange or conversion of such Derivative
                        Securities shall be pursuant to the terms thereof.

        2.      OPTION. (a) From and after the Effective Date until Parent fails
to exercise its right under Section 2(b) and so long as a result of such failure
is that Parent loses its ability to consolidate the Company with Parent under
Section 1504 of the Code, prior to an Option Event (as defined in Section 4(a)
below) that (i) would result in Parent owning less than 82% of the voting power
or value of the Company (the "PERCENTAGE THRESHOLD") as determined pursuant to
the principles established under Section 1504 of the Internal Revenue Code of
1986, as amended from time to time, or any successor provision, and the rules
and regulations promulgated thereunder (the "CODE"), or (ii) could be reasonably
interpreted by the Internal Revenue Service to decrease Parent's ownership
percentage of the Company below the percentage or percentages

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required to satisfy the consolidation tests of Section 1504 of the Code (the
"TAX THRESHOLD"), the Company shall send written notice thereof to Parent not
less than forty-five (45) days prior to such Option Event.

        (b)     Parent will have the right, by sending irrevocable written
notice thereof to the Company within thirty (30) days after receipt of the
Company's notice, to purchase such securities as are set forth in Section 3(b)
up to that number of such securities as is necessary to maintain the Percentage
Threshold or satisfy the Tax Threshold, as the case may be.

        (c)     Prices to Parent will be as set forth in Section 1(c) or Section
2(f).

        (d)     Subject to the limitations and exclusions set forth in the next
sentence, the Company shall indemnify Parent and its Affiliates (other than the
Company and its subsidiaries) (collectively, the "INDEMNIFIED PARTIES") against,
and hold each Indemnified Party harmless from, any damage, claim, loss, cost,
liability or expense, including interest, penalties and reasonable attorneys'
fees (collectively, the "DAMAGES") incident to, arising out of, in connection
with or related to, whether directly or indirectly, a breach by the Company of
this Section 2, including, without limitation, any federal or state tax
liability. Notwithstanding the foregoing, (i) to the extent Parent's loss of its
ability to consolidate the Company with Parent under Section 1504 of the Code
can be restored by the Company's issuance, and Parent's purchase, of additional
shares of Capital Stock, and the Company offers to issue, but Parent fails to
purchase, such additional shares, then the Company will not be liable under this
Section 2(d) to the extent Damages result from the loss of such ability to
consolidate in the tax year or years for which tax consolidation status would
have been restored if the Company had purchased such shares, and (ii) if a
majority of the Parent Affiliate Directors vote in favor of a Proposed Issuance,
the Company will not be liable for any Damages resulting from such Proposed
Issuance under this Section 2(d).

        (e)     If a Proposed Issuance is governed by both Section 1 and Section
2, then Parent will have the right to purchase such number of shares as is
necessary to maintain its Voting Power Ownership Percentage, its Fully Diluted
Ownership Percentage, the Tax Threshold or the Percentage Threshold, whichever
is greatest.

        (f)     The Company and Parent will negotiate in good faith to reach
agreement prior to consummation of the IPO on procedures and mechanisms to be
implemented to provide Parent with a periodic opportunity to exercise its rights
to acquire additional shares of Capital Stock in anticipation of future issuance
of Capital Stock in Option Events that could reasonably be expected to occur
during the relevant future period. Any shares of Capital Stock acquired by
Parent as anticipated by this Section 2(f) shall be acquired at the Average
Price.

        3.      CLOSINGS. (a) A closing for the purchase of Capital Stock
pursuant to Section 1 or Section 2 (the "CLOSING") will occur, subject to the
receipt of any necessary Authorizations, on the later of (i) the date on which
such public or private issuance occurs, as the case may be, or (ii) such later
date as may be agreed to by Parent and the Company, at a time and place
specified by Parent in a notice provided to the Company at least ten (10) days
prior to the Closing. In connection with the Closing, the Company and Parent
shall provide such customary closing certificates and opinions as Parent and the
Company, as appropriate, reasonably request.

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        (b)     Where the securities being issued in any Proposed Issuance or
Option Event are either (A) Class A Common Stock, (B) Class B Common Stock, or
(C) Derivative Securities that are convertible into, or exercisable, or
exchangeable for (directly or indirectly ) Class A Common Stock and/or Class B
Common Stock, then Parent has the right, at its sole option, to maintain its
Voting Power Ownership Percentage, Fully Diluted Ownership Percentage, Tax
Threshold or Percentage Threshold, as the case may be, by purchasing one of the
following: (i) the Capital Stock being offered in a Proposed Issuance or Option
Event, as the case may be, (ii) Class B Common Stock, or (iii) if such Proposed
Issuance or Option Event, as the case may be, involves Derivative Securities
that are convertible into or exercisable or exchangeable for (directly or
indirectly) Class A Common Stock, substantially identical Derivative Securities
that instead shall be convertible into or exchangeable or exercisable for Class
B Common Stock.

        4.      MISCELLANEOUS.

        (a)     Definitions:

               "AFFILIATE" means, (i) as to any Person, another Person that
directly or indirectly through one or more intermediaries, Controls, or is
Controlled by, or is under common Control with, such Person and (ii) is
permitted to be included in a consolidated federal income tax return filed by
such Person (or by a group including such Person) pursuant to Section 1504 of
the Code, but excluding the Company and its subsidiaries. For the purposes of
this definition, "Control" when used with respect to any Person, means the
possession, directly or indirectly, of the power to direct or cause the
direction of the management and policies of such Person, whether through the
ownership of voting securities, by contract or otherwise; the terms
"Controlling" and "Controlled" have meanings correlative to the foregoing.

               "AUTHORIZATION" means any consent, approval or authorization of,
expiration or termination of any waiting period requirement of, or filing,
registration, qualification, declaration or designation with or by, any
Governmental Authority.

               "BUSINESS DAY" means any day on which there is trading on the
Nasdaq National Market.

               "FULLY DILUTED OWNERSHIP PERCENTAGE" means, as of the time of
determination thereof, the percentage ownership calculated by dividing (i) the
sum of (A) all shares of Capital Stock beneficially owned by Parent and its
Affiliates (other than the Company and its subsidiaries), howsoever and whenever
acquired by them, and (B) the total number of shares of Capital Stock
purchasable under any option (other than under Section 2 of this Agreement) held
by Parent or any of its Affiliates (other than the Company and its subsidiaries)
that has not expired by its terms, by (iii) the sum of (A) subsection (i) above
and (B) the Company's Fully Diluted Shares excluding those Fully Diluted Shares
included in subsection (i) of this definition above.

               "FULLY DILUTED SHARES" means the number of shares of Capital
Stock outstanding assuming the conversion of all securities convertible into
Class A Common Stock or other equity security of the Company, the exercise of
all options, warrants and rights to acquire Class A Common Stock or other equity
security of the Company, whether or not vested, and regardless of

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whether the exercise price of any option is above or below the then market price
and all restricted stock of the Company, in each case previously issued by the
Company and not terminated, cancelled or held in treasury by the Company,
whether or not treated as outstanding by the Company.

               "GOVERNMENTAL AUTHORITY" means any governmental or political
subdivision or department thereof, any governmental or regulatory body,
commission, board, bureau, agency or instrumentality, or any court or arbitrator
or alternative dispute resolution body, in each case whether domestic or
foreign, federal, state or local.

               "OPTION EVENT" means (i) a Proposed Issuance, (ii) the conversion
of convertible debt or convertible securities into Capital Stock, (iii) the
exercise of warrants or options to purchase Capital Stock, or (iv) any other
right granted by the Company or exercised by a Person to acquire Capital Stock.

               "PARENT AFFILIATE DIRECTOR" means a director of the Company who
is also a director, officer, employee or Affiliate (determined solely with
reference to clause (i) of the defined term "Affiliate") of Parent (other than
the Company and its subsidiaries).

               "PERSON" means an individual, partnership, corporation, limited
liability company, business trust, joint stock company, trust, unincorporated
association, joint venture, Governmental Authority or other entity of whatever
nature or a group, including without limitation, any pension, profit sharing or
other benefit plan or trust.

               "VOTING POWER OWNERSHIP PERCENTAGE" means the percentage
ownership calculated by dividing (i) the aggregate number of votes in the
election of Directors to which all shares of Voting Securities owned by Parent
and its Affiliates (other than the Company and its subsidiaries) are entitled,
howsoever and whenever acquired, by (ii) the aggregate number of votes in the
election of Directors to which all issued and outstanding Voting Securities are
entitled. For these purposes, Voting Securities issuable upon exercise or
conversion of options, warrants or other securities or rights will not be
included.

               "VOTING SECURITIES" means the Class A Common Stock, the Class B
Common Stock and all other classes of Capital Stock that are entitled to vote
generally in the election of Directors of the Company.

        (b)     Notices. Except as otherwise provided, all notices that are
permitted or required under this Agreement must be in writing and will be deemed
given (i) when delivered personally, (ii) if by fax, upon transmission with
confirmation of receipt by the receiving party's facsimile terminal, (iii) if
sent by documented overnight delivery service, on the date delivered or (iv) if
sent by mail, five (5) business days after being mailed by registered or
certified mail, return receipt postage prepaid, addressed as follows, or to such
other person or address as may be designated by notice to the other party:

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        If to the Parent, to:

        Nextel Communications, Inc.
        2001 Edmund Halley Drive
        Reston, VA   20191
        Attn:  General Counsel
        Phone:  (703) 433-4000
        Facsimile:  (703) 433-4036

        If to the Company, to:

        Nextel International, Inc.
        10700 Parkridge Boulevard, Suite 600
        Reston, VA   20191
        Attn:  General Counsel
        Phone:  (703) 390-5100
        Facsimile: (703)

        (c)     Assignment. This Agreement will be binding upon the parties
hereto and will inure to the benefit of the parties hereto and their legal
successors and permitted assigns. This Agreement and the transactions
contemplated hereby may not be assigned or otherwise transferred, in whole or in
part, by operation of law or otherwise, without the prior written consent of the
other party; provided, however, that Parent may assign this Agreement or any
right hereunder to one or more of its Affiliates (other than the Company and its
subsidiaries) that is or are part of Parent's consolidated group for federal
income tax purposes.

        (d)     Counterparts. This Agreement may be executed in two or more
counterparts, each of which when so executed and delivered, will be an original
instrument, but such counterparts together will constitute a single agreement.

        (e)     Governing Law. THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES HEREUNDER IS TO BE GOVERNED BY THE SUBSTANTIVE LAWS OF THE STATE OF
DELAWARE APPLICABLE TO CONTRACTS MADE AND TO BE PERFORMED THEREIN, WITHOUT
GIVING EFFECT TO THE CONFLICTS OF LAWS RULES THEREOF.

        (f)     Headings. The headings contained in this Agreement are for
reference purposes only and do not affect the meaning or interpretation of this
Agreement.

        (g)     Severability. Any provision of this Agreement which is invalid
or unenforceable will be ineffective to the extent of such invalidity or
unenforceability, provided that such invalidity or unenforceability does not
deny any party the material benefits of the transactions for which it has
bargained, such invalidity or unenforceability will not affect in any way the
remaining provisions hereof.

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        (h)     Modification and Amendment. This Agreement may not be modified
or amended except by written agreement specifically referring to this Agreement
and signed by the parties hereto.

        (i)     Waiver. No waiver of a breach or default hereunder will be
considered valid unless in writing and signed by the party giving such waiver,
and no such waiver will be deemed a waiver of any subsequent breach or default
of the same or similar nature.

        (j)     Further Assurances. The Company and Parent shall develop a
mutually agreeable procedure that permits on a quarterly basis (or as otherwise
agreed) the purchase of Capital Stock by Parent in anticipation of the exercise
of options to purchase Capital Stock by the holders thereof or other potential
issuances based on rights outstanding. If Parent purchases Capital Stock
pursuant to this procedure, Parent's right to make additional anticipated
purchases will cease until all options or other rights anticipated by such
purchase result in issuance of Capital Stock.

        (k)     Effective Date. This Agreement shall become effective upon the
closing of the sale under the underwriting agreement related to the IPO (the
"EFFECTIVE DATE").

               IN WITNESS WHEREOF, this Agreement has been duly executed and
delivered by the parties hereto on the day and year first written above.

                                NEXTEL COMMUNICATIONS, INC.
                                By: /s/ JOHN S. BRITTAIN, JR.
                                   --------------------------------
                                     Name:  John S. Brittain, Jr.
                                     Title:  Vice President and
                                              Chief Financial Officer

                                NEXTEL INTERNATIONAL, INC.
                                By: /s/ ROBERT J. GILKER
                                   -----------------------------------
                                     Name:  Robert J. Gilker
                                     Title:  Vice President and General
                                                  Counsel

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