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                                  EXHIBIT 10.1

                    MODIFICATION AND REAFFIRMATION AGREEMENT


         THIS MODIFICATION AND REAFFIRMATION AGREEMENT (this "Modification
Agreement") is made and entered into as of the 12th day of March, 1998, by and
between PAGEMART WIRELESS, INC., a Delaware corporation and successor in
interest by merger to PAGEMART, INC.("Maker"), and GLENAYRE ELECTRONICS, INC., a
Colorado corporation ("Glenayre").

Statement of Purpose

         Maker and Glenayre have previously entered into a Promissory Note and
Security Agreement dated as of March 21, 1997 (the "Note"), providing for the
extension of certain purchase money financing by Glenayre to Maker in the
maximum principal amount of up to $30,000,000. Except as otherwise provided
herein, all capitalized terms used but not otherwise defined herein shall have
the meanings assigned thereto in the Note.

         The Note has previously been supplemented by various Schedules in
accordance with the terms of the Note and, as of the date hereof, pursuant to
the terms of the Note and the Schedules, Maker owes Glenayre an amount equal to
$20,766,396.40 (the "Existing Glenayre Indebtedness"), of which $20,686,371.80
is unpaid principal and $80,024.60 is accrued but unpaid interest.

         Maker now desires, in accordance with the terms of Section 1.2 of the
Note, to prepay in full the Existing Glenayre Indebtedness but, in connection
therewith has requested certain modifications and amendments to the Note,
including, without limitation, the right to obtain additional purchase money
financing from Glenayre in an aggregate amount not to exceed the Commitment
during the period from September 1, 1998 through and including December 31, 2000
pursuant to the terms of the Note, and Glenayre has agreed to such modifications
in accordance with the terms hereof, subject to the terms and conditions
contained herein.

         In furtherance of the foregoing, Maker and Glenayre have agreed to
modify and amend the terms of the Note, all as more particularly described
herein.

         NOW, THEREFORE, for and in consideration of the premises, the mutual
agreements and covenants hereinafter set forth and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Maker and Glenayre hereby agree as follows:

         1. EFFECT OF MODIFICATION AGREEMENT. This Modification Agreement shall
modify and amend the Note as set forth or provided for herein. Except as
expressly modified hereby or by those other documents, agreements and
instruments referred to herein, the Note and the other documents executed or
delivered in connection herewith or therewith, including without limitation each
representation, warranty and covenant contained herein or therein, shall be and
remain in full force and effect.

         2. PURPOSE OF MODIFICATION. The purpose of this modification is to (i)
provide for the right for Maker to obtain, after payment in full of the Existing
Glenayre Indebtedness and compliance by Maker with each of the terms and
conditions of the Note and this Modification Agreement, additional purchase
money financing from Glenayre in an aggregate amount not to exceed the
Commitment during the period from September 1, 1998 through and including
December 31, 2000, and (ii) make certain additional changes to the Agreement, as
set forth herein and subject to the terms hereof.

         3. AMENDMENTS TO NOTE. In furtherance of the foregoing, the Note is
hereby amended as follows:


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         (a) The term "Maturity Date" contained in Section 9 of the Note is
hereby deleted in its entirety and the following definition is inserted in lieu
thereof:

         " 'Maturity Date' means, with respect to advances reflected on each
Schedule, that date which is five (5) years from the date of such Schedule,
provided that all Schedules commence no later than December 31, 2000."

         (b) The term "Note" contained in Section 9 of the Note is hereby
deleted in its entirety and the following definition is inserted in lieu
thereof:

         " 'Note' means the Promissory Note and Security Agreement dated as of
March 21, 1997 made by Maker to the order of Glenayre, as amended by this
Modification Agreement and as it may be further modified, amended, restated or
supplemented from time to time."

         (c) The term "Schedule" contained in Section 9 of the Note is hereby
deleted in its entirety and the following definition is inserted in lieu
thereof:

         " 'Schedule' means documentation evidencing (i) purchases by Maker from
Glenayre during the period from September 1, 1998 through and including December
31, 2000 and (ii) the Interest Rate, payments and amortization of principal
amount applicable for such purchases."

         (d) The following new definition shall be added to Section 9 of the
Note in the appropriate alphabetical order:

         " 'Modification Agreement' means the Modification and Reaffirmation
Agreement dated as of March 12, 1998 between Maker and Glenayre."

         (e) The Schedules executed prior to the date of the Modification
Agreement shall be of no further force or effect.

         (f) The amount in Section 6.11 (a) is modified from $500,000 to
$5,000,000.

         (g) The following phrase is added to Section 7.3 (b) after "dated May
22, 1995" and before";":

         "as amended, restated, refinanced or replaced from time to time; "

         (h) The following Subsidiaries are added to Schedule_7.3(c):

         PageMart de Colombia, Ltd.
         PageMart de Venezuela, C.A.
         PageMart California, Inc.
         PageMart Virginia, Inc.

         (i) Maker shall not be entitled to obtain any financing from Glenayre
except during the period from September 1, 1998 through and including December
31, 2000, and then only in accordance with, and as permitted under, the terms of
the Note.

         4. REAFFIRMATION OF REPRESENTATIONS AND WARRANTIES, ETC. Except as
modified herein, the Note remains in full force and effect, and Maker hereby
expressly represents and warrants that all covenants, representations and
warranties specified in the Note, as amended and modified by this Modification
Agreement, are true and correct as of this date.

         5. NO DEFENSES. Maker hereby acknowledges and affirms that it has no
defenses, legal or equitable, to the validity and enforceability of the Note,
or, except as otherwise expressly set forth herein with


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respect to the Schedules executed prior to the date hereof, any other document
or instrument executed or delivered in connection therewith.

         6. CONDITIONS PRECEDENT. Glenayre's obligations hereunder are subject
to the following conditions precedent, all of which must be satisfied prior to
the execution and delivery hereof by Glenayre:

         (a) Modification Documents. This Modification Agreement, shall be duly
executed and delivered and in form and substance satisfactory to Glenayre.

         (b) Status and Authority of Borrower and Guarantors. Maker shall, if
requested by Glenayre, furnish or cause to be furnished to Glenayre a certified
document in form and substance satisfactory to Glenayre (collectively, the
"Certificate and Resolution") evidencing the power and authority of Maker to
execute and deliver this Modification Agreement and to perform the terms and
provisions of the Note, as amended and modified by this Modification Agreement.

         (c) Payoff of Existing Glenayre Indebtedness. Maker shall have caused
the Existing Glenayre Indebtedness to be paid in full to Glenayre, in accordance
with Glenayre's instructions, in immediately available funds in Charlotte, North
Carolina.

         7. REPRESENTATIONS AND WARRANTIES. Maker hereby further represents and
warrants to Glenayre as follows:

         (a) Power and Authority; Enforceability. Maker has the power and
authority to execute and deliver this Modification Agreement and to perform the
terms and conditions of the Note, as amended and modified by this Modification
Agreement. The execution and delivery of this Modification Agreement by Maker
and the performance of the Note, as amended and modified by this Modification
Agreement, do not and will not violate any law, rule or regulation, or
constitute a breach of the articles, bylaws or corporate resolutions of Maker or
any agreement to which Maker is a party or by which its assets are bound. The
Note, as amended and modified by this Modification Agreement, constitutes the
legal, valid and binding obligation of Maker enforceable in accordance with its
terms.

         (b) No Default or Event of Default. There is no Default or Event of
Default under the Note, as amended and modified by this Modification Agreement,
and Maker is not in default in the performance, observance or fulfillment of any
of the obligations, covenants or conditions contained in any other document or
instrument executed or delivered in connection herewith or therewith.

         (c) Representations. The representations and warranties of Maker to
Glenayre contained herein, in the Note as modified by this Modification
Agreement, and in any other document, agreement or instrument executed or
delivered by Maker in connection therewith are true and not misleading in all
material respects, except as otherwise disclosed in writing to Glenayre and
approved by Glenayre prior to the date hereof.

         8. RELEASE OF SECURITY INTERESTS. Glenayre hereby releases the
Collateral existing on the date of this Modification Agreement from all security
interests, liens and encumbrances, and all rights in such Collateral revert to
Maker. Glenayre shall promptly execute and deliver to Maker such UCC-3 forms and
such other release or termination documents as may be required to evidence this
release in the public records where evidence of such security interests, liens
or encumbrances have been filed.



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         IN WITNESS WHEREOF, Maker and Glenayre have caused this Modification
Agreement to be duly executed and delivered under seal by their duly authorized
officers, all as of the day and year first above written.

[CORPORATE SEAL]                             PAGEMART WIRELESS, INC.,
                                             a Delaware corporation

ATTEST:

By: /s/ Frederick G. Anderson                By: /s/ Clay Myers
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Name: Frederick G. Anderson                  Name: G. Clay Myers
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Title: V.P., General Counsel & Secretary     Title: V.P. Finance & CFO
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[CORPORATE SEAL]                             GLENAYRE ELECTRONICS, INC.,

ATTEST:


By: /s/ Billy G. Layton                      By: /s/ Mary T. Velenta
   -------------------------------------        --------------------------------
Name: Billy G. Layton                        Name: Mary T. Velenta
     -----------------------------------          ------------------------------
Title: Assistant Secretary                   Title: V.P and Treasurer
      ----------------------------------           -----------------------------