Document:

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                                                                    EXHIBIT 10.1

                                    AGREEMENT

        This Agreement is dated August 9, 2001 by and among Nextel
Communications, Inc., a Delaware corporation ("COMPANY"), Digital Radio, L.L.C.,
a Washington limited liability company ("INVESTOR") and Craig O. McCaw
("INDIVIDUAL").

                                   BACKGROUND

        A.    The parties to this Agreement are also parties to the Securities
Purchase Agreement, dated as of April 4, 1995, (the "SECURITIES PURCHASE
AGREEMENT") pursuant to which Investor acquired Class A Convertible Redeemable
Preferred Stock of the Company ("CLASS A PREFERRED") and shares of Class B
Convertible Preferred Stock of the Company ("CLASS B PREFERRED").

        B.    Under the Securities Purchase Agreement, under the Restated
Certificate of Incorporation of the Company (the "CERTIFICATE") and under the
Bylaws of the Company (the "BYLAWS"), Investor has rights to representation on
the "Operations Committee," a committee of the Board of the Company. Under
certain circumstances, defined in the Securities Purchase Agreement and the
Certificate, there may be certain consequences if the Board acts to abrogate
the power of the Operations Committee or overrule an Operations Committee
decision.

        C.    Investor recently made distributions of Company stock to members
of Investor, which could, under certain circumstances, change the rights and
remedies of the parties under the Securities and Purchase Agreement and the
Certificate. The parties desire to adjust their relationships as set forth in
this Agreement.

                                    AGREEMENT

        NOW THEREFORE, in consideration of the mutual covenants of this
Agreement, the parties agree:

        1.    Investor represents and warrants that the holdings of the Investor
Group (as defined in the Securities Purchase Agreement) of the Company's Common
Stock (including, Class A Preferred and Class B Preferred on an as converted
basis) are 53,103,794 shares.

        2.    Section 3.3 of the Securities Purchase Agreement is amended to
delete the introductory paragraph of subsection (c) and clauses (i) through (iv)
and to replace them with the following; the remainder of the Section 3.3
(including, clauses (v), (vi), and (vii) of subsection (c)) remain unchanged.

              (c) The lump-sum payment described in Section 3.3(b) shall not
        occur in connection with a Trigger Event if (x) the Board, by the vote
        of a majority of the non-Investor Directors who are Independent (as
        defined in Section 3.2), votes to overrule a decision taken by the
        Operations Committee or to take action contrary to the recommendation of
        the Operations Committee; or (y) the Trigger Event occurs by the lessor
        of (1) the Required Vote or (2) the vote of a majority of all the
        members of the Board then in office after:

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                        (i)     a Cause event applicable to Individual or any
                                member of the Investor Group other than an event
                                that would permit removal of an Investor
                                Director (other than Individual) under Section
                                3.8;

                        (ii)    advance approval of the Trigger Event by the
                                vote of a majority of the members of the
                                Operations Committee;

                        (iii)   [Reserved];

                        (iv)    at any time after July 28, 2005, the failure of
                                the Investor Group's holdings of Common Stock
                                (including, Class A Preferred and Class B
                                Preferred on an as converted basis) to be at
                                least 66-2/3% of Investor's Common Stock
                                Holdings;

        3. The definition of "Common Stock Holdings" in Section 10.1 of the
Securities Purchase Agreement is hereby amended to read in its entirety, as
follows:

              "COMMON STOCK HOLDINGS" means a number of shares (from whatever
        source) equal to the following number of shares: (A) the Initial Common
        Shares plus (B) the Common Stock issued or issuable as a result of the
        conversion of the Class A Preferred Shares (and any Class C Preferred
        Shares into which Class A Preferred Shares have been converted) and/or
        the Class B Preferred Shares plus (C) all Common Stock acquired pursuant
        to exercise of the Options by Investor or its assignees, in each case
        subject to any adjustments to reflect changes in the Company's capital
        structure.

        4. The parties confirm that Section 3.6 of the Securities Purchase
Agreement is superseded by the express terms of the Class A Preferred and that,
in the event of any inconsistency, the terms of the Class A Preferred control.
The parties confirm that Section 3.7 of the Securities Purchase Agreement is
superseded by the express terms of the Class B Preferred and that, in the event
of any inconsistency, the terms of the Class B Preferred control.

        5. Until July 28, 2005, or until the earlier of the termination of the
Operations Committee or the occurrence of an event constituting Cause (as
defined by Section 3.3(e)(i) of the Securities Purchase Agreement) with respect
to Individual, Individual agrees to serve as a member of the Board of the
Company as one of the Investor Directors and as a member of the Operations
Committee and Investor agrees to designate Individual as one of the Investor
Directors pursuant to Section 3.1 and as a member of the Operations Committee
pursuant to Section 3.2.

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        IN WITNESS WHEREOF, the parties have executed or caused this Agreement
to be executed as of the date first above written.

                                    DIGITAL RADIO, L.L.C.

                                    By:
                                        ----------------------------------
                                        Name: /s/ C. JAMES JUDSON
                                             -----------------------------
                                        Title: Vice President
                                              ----------------------------

                                    NEXTEL COMMUNICATIONS, INC.

                                    By:
                                        ----------------------------------
                                        Name:  Timothy M. Donahue
                                               President & Chief Executive
                                               Officer

                                    --------------------------------------
                                    Craig O. McCaw

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                                                                    EXHIBIT 10.4

                        AGREEMENT TO DEFER BONUS PAYMENT

         This AGREEMENT TO DEFER BONUS PAYMENT (this "Agreement") is executed
this 27th day of July 2001, but with effect as of June 12, 2001, between TREMONT
CORPORATION, a Delaware corporation (the "Corporation"), and J. Landis Martin
("Executive").

         WHEREAS, on June 12, 2001, the Board of Directors of the Corporation
awarded Executive a special bonus of one million dollars ($1,000,000.00) in
recognition of his performance in connection with the settlement of certain
litigation with The Boeing Company, which settlement substantially contributed
to the success of the Corporation (the "Special Bonus"); and

         WHEREAS, payment of the Special Bonus will be deferred in accordance
with the terms set forth in Section 1 below; and

         NOW, THEREFORE, in consideration of the agreements set forth herein and
for other good and valuable consideration, the receipt and sufficiency of which
is hereby acknowledged, the parties hereto agree as follows:

         1. The Corporation will pay the Special Bonus to Executive in five (5)
equal annual installments on June 12 of each year commencing on June 12, 2002,
with all unpaid principal and interest due and payable on June 12, 2006 (the
"Maturity Date"); provided, however, if the payment of such amount at such time
would not be deductible to Maker for tax purposes under the provisions of
Section 162(m) of the Internal Revenue Code of 1986, as amended, or any
successor provision, the Corporation may defer such payment until the earliest
time at which the payment of such amount would be deductible by the Corporation.
The Corporation, acting through its Management Development & Compensation
Committee, may elect, in its sole discretion, to make payment of all or any
portion of the Special Bonus prior to the Maturity Date without penalty or
premium.

         2. The Corporation shall immediately make and deliver to Executive a
non-negotiable promissory note (the "Note") representing the full amount of the
Special Bonus with payment terms as provided in Section 1 above.

         3. All unpaid Special Bonus shall accrue interest beginning on June 12,
2001, as provided in the Note.

         4. The Corporation shall withhold, either from the Special Bonus (or
any portion thereof) in the year such amount is paid to Executive pursuant to
Section 1 hereof, or from any salary, bonus or other compensatory payment made
to Executive as the Corporation in its sole discretion may determine, such
amounts as are required by law to be withheld pursuant to the Code and any other
applicable withholding requirements.

         5. Any right of Executive or any of his designated beneficiaries to
receive payments from the Corporation under this Agreement or under the Note
shall be no greater than the right of any unsecured general creditor of the
Corporation.

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         6. The right of Executive or any other person to any payment under this
Agreement may not be assigned, transferred, pledged or encumbered except by will
or by the laws of descent and distribution.

         7. Nothing contained herein shall be construed as conferring upon
Executive the right to continue in the employ of the Corporation, whether as an
employee, executive officer, or in any other capacity.

         8. This Agreement shall be binding upon and inure to the benefit of the
Corporation, it successors and assigns, and Executive and his heirs, designated
beneficiaries, executors, administrators and legal representatives.

         9. This Agreement contains the entire agreement of and between the
parties with respect to the subject matter hereof, and supersedes any prior
understanding, agreements, or representations by or between the parties, written
or oral, which may have related to the subject matter hereof in any way. In the
event of any conflict between the terms and provisions of this Agreement and the
terms and provisions of any employment or severance agreement entered into by
the parties hereto, the terms and provisions of this Agreement shall govern.

         10. This Agreement shall be governed by the laws of the State of
Colorado without giving effect to any choice of law or conflict of law provision
or rule (whether of the State of Colorado or any other jurisdiction) that would
cause the application of the laws of any jurisdiction other than the State of
Colorado.

                                    * * * * *

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first written above.

                                          TREMONT CORPORATION

                                          By: /s/ Robert E. Musgraves
                                             -----------------------------------

                                          Its: Vice President
                                              ----------------------------------

                                          EXECUTIVE

                                          /s/ J. Landis Martin
                                          --------------------------------------
                                                     J. Landis Martin

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