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                                                                    EXHIBIT 10.3



                                OPTION AGREEMENT

         OPTION AGREEMENT, dated as of March 17, 2000 (this "Agreement"), by and
among Metrocall, Inc., a Delaware corporation ("Company"), and HMTF Bridge MC I,
LLC, a Delaware limited liability company ("HMTF Bridge" or a "Holder"), HM 4-EQ
Metrocall Coinvestors, LLC, a Delaware limited liability company, HM 4-SBS
Metrocall Coinvestors, LLC, a Delaware limited liability company, HM PG-IV
Metrocall, LLC, a Delaware limited liability company, HM4 Metrocall Qualified
Fund, LLC, a Delaware limited liability company, and HM4 Metrocall Private Fund,
LLC, a Delaware limited liability company (each individually a "Holder" and
collectively, together with HMTF Bridge, "Holders").

         WHEREAS, the Company and HMTF Bridge entered into a Common Stock
Purchase Agreement dated February 2, 2000 (the "Purchase Agreement"), pursuant
to which the Company agreed to sell and HMTF Bridge agreed to purchase shares of
common stock, $0.01 par value per share ("Common Stock"), of the Company;

         WHEREAS, HMTF Bridge and HM 4-EQ Metrocall Coinvestors, LLC, a Delaware
limited liability company, HM 4-SBS Metrocall Coinvestors, LLC, a Delaware
limited liability company, HM PG-IV Metrocall, LLC, a Delaware limited liability
company, HM4 Metrocall Qualified Fund, LLC, a Delaware limited liability
company, and HM4 Metrocall Private Fund, LLC, a Delaware limited liability
company entered into that certain Assignment of Rights Under Common Stock
Purchase Agreement dated February 17, 2000, pursuant to which HMTF Bridge
assigned a total of 50% of its interest under the Purchase Agreement, the
interests of each Holder with respect to this Agreement are set forth on Exhibit
A;

         WHEREAS, the Company desires, upon the terms and subject to the
conditions set forth herein, to grant Holders the right to acquire additional
shares of Common Stock.

         NOW, THEREFORE, in consideration of the foregoing and the agreements
set forth below, the parties hereto agree as follows:

         1. Option I.

                  (a) Grant of Option. Company hereby grants to Holders an
irrevocable option ("Option I") to purchase, in the manner set forth below, an
aggregate of 8,333,333 shares of Common Stock (the "Option I Shares"), at an
exercise price per share of Three Dollars ($3.00) (the "Option I Exercise
Price"), subject to adjustment in accordance with Section 9. Each Holder's
interest in the Option I Shares is set forth opposite such Holder's name on
Exhibit A hereto.

                  (b) Term of Option. Option I may be exercised by the Holders
in whole but not in part, at any time or from time to time after the date hereof
and on or before 5:00 pm, Eastern time, on March 17, 2001 (the "Option I
Expiration Date"). Except as provided in


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Section 2, Option I will terminate and be null and void if the Option I Exercise
Notice (as defined herein) is not delivered on or prior to the Option I
Expiration Date.

                  (c) Exercise Procedures.

                           (i)      In the event Holders wish to exercise Option
                                    I, Holders shall send a written notice to
                                    that effect to Company ("Option I Exercise
                                    Notice"). Such notice shall be irrevocable,
                                    subject to the satisfaction of the
                                    conditions set forth in Section 4.

                           (ii)     Closing of the purchase of Common Stock
                                    pursuant to Option I (the "Option I
                                    Closing") shall occur at a place, on a date,
                                    and at a time designated by Holders in the
                                    Option I Exercise Notice which date shall be
                                    at least three Business Days after the date
                                    of the Option I Exercise Notice.

                           (iii)    At the Option I Closing, the Company shall
                                    deliver certificates representing the Option
                                    I Shares to Holders or their assignees
                                    against payment of the Option I Exercise
                                    Price in cash by wire transfer of
                                    immediately available funds to a bank
                                    account designated by the Company.

         2. Option II.

                  (a) Grant of Option. Company hereby grants to Holders an
irrevocable option ("Option II", together with Option I, the "Options") to
purchase, in the manner set forth below, (i) an aggregate of 12,500,000 shares
of Common Stock at an exercise price per share of Four Dollars ($4.00) plus
(ii), if Holders have not exercised Option I, 8,333,333 shares of Common Stock
at an exercise price per share of Three Dollars ($3.00), in each case subject to
adjustment in accordance with Section 9. (The shares subject to Option II shall
be referred to as the "Option II Shares.") Each Holder's interest in Option II
Shares is set forth opposite such Holder's name on Exhibit A hereto.

                  (b) Term and Conditions of Option. Option II may be exercised
in whole or in part, only in connection with the issuance of new equity for cash
to finance a business combination or acquisition (by means of merger,
consolidation, exchange, or acquisition of assets, or otherwise) involving the
Company or any subsidiary thereof and an aggregate transactional consideration
to the other entity or its equity and debt holders or to the Company and its
equity and debt holders having a fair value (as determined in good faith by the
Board of Directors of the Company) of at least $50,000,000 (a "Qualified
Transaction"). Except as otherwise provided in Sections 2(c)(i) and 2(d), Option
II shall only be exercisable as to Transaction Notices delivered by the Company
on or prior to 5:00 pm, Eastern time, on March 17, 2002 (the "Termination
Date").

                  (c) Exercise Procedures.

                           (i)      If, at any time prior to the Termination
                                    Date, the Company proposes to enter into one
                                    or more Qualified Transactions, it shall



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                                    in each case promptly notify the Holders in
                                    writing of the material terms of the
                                    Qualified Transaction (a "Transaction
                                    Notice"). Holders shall have 20 Business
                                    Days from the date of a Transaction Notice
                                    ("Option II Exercise Period") to notify the
                                    Company in writing ("Option II Election
                                    Notice") whether or not it intends to
                                    exercise Option II in connection with the
                                    proposed Qualified Transaction. Except as
                                    provided for in the immediately following
                                    sentence, if the Holders notify the Company
                                    in the Option II Election Notice that they
                                    do not intend to exercise Option II in
                                    connection with the proposed Qualified
                                    Transaction, or does not deliver an Option
                                    II Election Notice within the Option II
                                    Exercise Period, then Option II shall
                                    terminate and become null and void upon the
                                    consummation of such Qualified Transaction.
                                    If after the delivery of a Transaction
                                    Notice there is any change in the material
                                    terms of the Qualified Transaction, the
                                    Company shall deliver a new Transaction
                                    Notice specifying such change and a new
                                    Option II Exercise Period shall commence and
                                    during such new Option II Election Period,
                                    Holders shall have the right to either (x)
                                    withdraw any prior Option II Election Notice
                                    or (y) elect to exercise Option II by means
                                    of a new Option II Election Notice. Any
                                    portion of Option II that (1) remains
                                    unexercised in the case of a partial
                                    exercise as provided above or (2) represents
                                    shares of Common Stock as to which an
                                    affirmative Option II Election Notice has
                                    been given but as to which the related
                                    Qualified Transaction has been abandoned,
                                    terminated or otherwise withdrawn, shall in
                                    each case remain in full force and effect
                                    herein.

                           (ii)     Simultaneously with its delivery of the
                                    Transaction Notice to the Holders and
                                    continually throughout the Option Exercise
                                    Period, the Company shall promptly provide
                                    the Holders with all material information
                                    relating to the Qualified Transaction and
                                    the parties thereto, including financial and
                                    operating data, business plans and
                                    projections and any other material
                                    information that the Holders may reasonably
                                    request.

                           (iii)    If the Holders notify the Company in the
                                    Option II Election Notice that they do
                                    intend to exercise Option II in connection
                                    with the proposed Qualified Transaction,
                                    then upon execution by the Company of a
                                    binding agreement for the proposed Qualified
                                    Transaction, the Holders shall be deemed to
                                    have irrevocably exercised Option II,
                                    subject to the satisfaction of the
                                    conditions set forth in Section 4 and the
                                    provisions of Section 2(c)(i).

                           (iv)     Closing of the purchase of Common Stock
                                    pursuant to Option II (the "Option II
                                    Closing") shall occur contemporaneously with
                                    the consummation of the Qualified
                                    Transaction at a place and at a time that
                                    shall be mutually agreed to by the parties
                                    hereto. The Option



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                                    II Closing shall be subject to the
                                    fulfillment of all conditions to the
                                    Company's obligations to consummate the
                                    Qualified Transaction, unless the Holders
                                    shall have consented to the Company's waiver
                                    of any such condition.

                           (v)      At the Option II Closing, the Company shall
                                    deliver certificates representing the Option
                                    II Shares to the Holders or their assignees
                                    against payment of the applicable Exercise
                                    Price in cash by wire transfer of
                                    immediately available funds to a bank
                                    account designated by the Company.

                           (vi)     In connection with any proposed Qualified
                                    Transaction as to which a Transaction Notice
                                    and an affirmative Option II Election Notice
                                    has been given, the Company shall use
                                    reasonable efforts to accommodate Holders'
                                    reasonable requests with respect to the
                                    timing, form, and structure of such
                                    Qualified Transaction and the related Option
                                    II Closing in order to achieve Holders'
                                    desired tax, corporate and securities law
                                    treatment; provided, that no action shall be
                                    required hereunder that in the good faith
                                    judgment of the Company would adversely
                                    affect such Qualified Transaction in any
                                    material respect.

                  (d) Extension of Termination Date. If on the Termination Date,
the Company is then engaged in active discussions with a party regarding a
potential Qualified Transaction, then the Termination Date shall be extended
until the earlier date of (i) the termination of such discussions without any
Qualified Transaction being proposed or (ii) the Company delivering a
Transaction Notice.

         3. Covenants.

                  (a) If applicable, the parties will file as soon as
practicable all filings that are required under the Hart-Scott-Rodino Antitrust
Improvements Act of 1976 ("HSR Act") relating to the issuance of the Option I
Shares or the Option II Shares, respond as soon as practicable to all inquiries
received from the Federal Trade Commission or the Antitrust Division of the
Department of Justice for additional information or documentation, respond as
soon as practicable to all inquiries received from any other government agency
in connection with antitrust matters, and seek early termination of any waiting
period under the HSR Act.

                  (b) The Company shall use its best efforts to obtain all
consents, approvals, orders or authorizations of, or registrations, declarations
or filings with, any federal administrative agency or commission or other
federal governmental authority or instrumentality, if any, required in
connection with the issuance of the Option I Shares or Option II Shares, as the
case may be, hereunder.

                  (c) The Company will file with the Nasdaq Small Cap Market a
Notification Form for Listing of Additional Shares for an amount of shares of
Common Stock equal to at least the amount of the Option I Shares and the Option
II Shares and will use its reasonable best



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efforts to ensure that the Option I Shares and Option II Shares are encompassed
within its listing on the Nasdaq Small Cap Market or such other exchange or
market as the shares of Common Stock may subsequently be listed.

                  (d) If necessary to effectuate the transactions contemplated
by this Agreement, Company shall prepare, file and prosecute any required
applications for the consents of the Federal Communications Commission ("FCC")
to the transactions contemplated herein (the "FCC Consents") and in connection
therewith request special temporary authorizations to permit the Closing to
occur prior to obtaining the FCC Consents.

         4. Conditions to Closing.

                  (a) The obligation of Company to issue the Option I Shares or
Option II Shares, as applicable, to Holders hereunder is subject to the
conditions that

                           (i) all waiting periods, if any, under the HSR Act
applicable to the issuance of the Option I Shares or Option II Shares hereunder
shall have expired or been terminated and all consents, approvals, orders or
authorizations of, or registrations, declarations or filings with, any federal
administrative agency or commission or other federal governmental authority or
instrumentality, if any, required in connection with the issuance of the Option
I Shares or Option II Shares hereunder shall have been obtained or made, as the
case may be;

                           (ii) No preliminary or permanent injunction or other
order shall have been issued by any federal or state court of competent
jurisdiction in the United States or by any U.S. federal or state governmental
or regulatory body, and no statute, rule, regulation or executive order shall
have been promulgated or enacted by any U.S. federal or state governmental
authority which restrains, enjoins or otherwise prohibits in any material
respects the issuance of the Option I Shares or the Option II Shares, as the
case may be.

                           (iii) The representations and warranties of the
Holders contained in this Agreement (A) shall have been true and correct when
made and (B) in the case of representations and warranties that are qualified as
to materiality or material adverse effect, true and correct and (B) in all other
cases, true and correct in all material respects, in the case of clauses (A) and
(B), as of the Option I Closing date or the Option II Closing date, as the case
may be, with the same force and effect as though made on and as of such
applicable closing date.

                           (iv) If required, the parties shall have obtained all
necessary FCC Consents in a form and substance typical of consents customarily
issued in transactions of this nature; provided however, that if no petitions to
deny the applications for the FCC Consents have been filed with the FCC, and the
time period for doing so has passed, then this condition shall be satisfied if
the Company has obtained special temporary authorizations to permit the Closing
to occur prior to obtaining the FCC Consents.

                  (b) The obligations of Holders to purchase the Option I Shares
or Option II Shares, as applicable, from the Company hereunder is subject to the
conditions that:

                           (i) all waiting periods, if any, under the HSR Act
applicable to the issuance of the Option I Shares or the Option II Shares
hereunder shall have expired or been



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terminated and all consents, approvals, orders or authorizations of, or
registrations, declarations or filings with, any federal administrative agency
or commission or other federal governmental authority or instrumentality, if
any, required in connection with the issuance of the Option I Shares or Option
II Shares hereunder shall have been obtained or made, as the case may be;

                           (ii) No preliminary or permanent injunction or other
order shall have been issued by any federal or state court of competent
jurisdiction in the United States or by any U.S. federal or state governmental
or regulatory body, and no statute, rule, regulation or executive order shall
have been promulgated or enacted by any U.S. federal or state governmental
authority which restrains, enjoins or otherwise prohibits in any material
respects the issuance of the Option I Shares or the Option II Shares, as the
case may be.

                           (iii) The representations and warranties of the
Company contained in this Agreement (A) shall have been true and correct when
made and (B) in the case of representations and warranties that are qualified as
to materiality or material adverse effect, true and correct and (B) in all other
cases, true and correct in all material respects, in the case of clauses (A) and
(B), as of the Option I Closing date or the Option II Closing date, as the case
may be, with the same force and effect as though made on and as of such
applicable closing date.

                           (iv) If required, the parties shall have obtained all
necessary FCC Consents in a form and substance typical of consents customarily
issued in transactions of this nature; provided however, that if no petitions to
deny the applications for the FCC Consents have been filed with the FCC, and the
time period for doing so has passed, then this condition shall be satisfied if
the Company has obtained special temporary authorizations to permit the Closing
to occur prior to obtaining the FCC Consents.

         5. Expenses. At any Closing, Company will pay all expenses that may be
payable in connection with the preparation, issuance and delivery of stock
certificates under this Agreement.

         6. Representations and Warranties of Company. The Company represents
and warrants to Holders as of the date hereof and as of the Option I Closing or
Option II Closing (unless another date or period of time is specifically stated
herein for a representation or warranty), as the case may be, as follows:

                  (a) The Company is a corporation duly organized, validly
existing and in good standing under the laws of the State of Delaware. The
Company has all requisite corporate power and authority to own and operate its
business as it currently is being conducted and to own and lease the properties
and assets owned or leased by it. The Company is licensed or qualified to do
business as a foreign corporation and is in good standing in each jurisdiction
in which the properties owned, leased or operated by it or the nature of its
business makes such qualification or licensing necessary, other than in such
jurisdictions where the failure to be so qualified or licensed has not had and
could not reasonably be expected to have a material adverse effect. The Company
has all requisite corporate power and authority to enter into this Agreement and
perform its obligations hereunder, and has taken all action necessary to
authorize the execution, delivery and performance by it of this Agreement. No
other corporate or stockholders



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proceeding on the part of the Company is necessary for such authorization,
execution, delivery and performance.

                  (b) Company has taken all necessary corporate action to
authorize and reserve for issuance and to permit it to issue, upon exercise of
the Options, and at all times from the date hereof through the expiration of the
Options will have reserved, 20,833,333 authorized and unissued shares of Common
Stock, such amount being subject to adjustment as provided in Section 9, (and
the Company will take all necessary corporate action to authorize and reserve
for issuance all additional shares of Common Stock or other securities that may
be issued pursuant to Section 9 upon exercise), all of which, upon their
issuance and delivery in accordance with the terms of this Agreement, will be
validly issued, fully paid, and non-assessable.

                  (c) Upon delivery of the Option I Shares or Option II Shares
to Holders upon the exercise of the applicable Option, the Option I Shares or
Option II Shares, as the case may be, shall be fully paid and non-assessable and
shall be acquired by Holders free and clear of all claims, liens, charges,
encumbrances and security agreements of any nature whatsoever (including without
limitation preemptive rights).

                  (d) Neither the execution and delivery of this Agreement, the
consummation by Company of the transactions contemplated hereby, nor the
compliance by Company with any of the provisions hereof will (i) conflict with,
or result in a breach of, any provision of its Certificate of Incorporation or
By-laws, (ii) require any permit, authorization, consent or approval of, or
filing with, or notification to (except for permits, authorizations, consents,
approvals, filings or notifications under the Securities Exchange Act of 1934 as
amended (the "Exchange Act"), the Securities Act of 1933, as amended (the
"Securities Act"), the HSR Act, the Communications Act of 1934, as amended (the
"Communications Act"), or state public utility or public service laws (if any))
any Governmental Authority (as defined in the Purchase Agreement), (iii)
conflict with, or result in a violation or breach of, or constitute (with or
without due notice or lapse of time or both) a default (or give rise to any
right of termination, cancellation or acceleration or loss of any material right
or benefit) under any of the terms, conditions or provisions of any Company
Third Party Contracts (as defined in the Purchase Agreement), (iv) require any
consent, authorization, waiver or approval of any person other than a
Governmental Authority, or (vi) violate any order, writ, injunction, decree or
law applicable to Company, excluding from the foregoing clauses (ii)-(vi) such
violations, breaches or defaults which would not, individually or in the
aggregate, have a material adverse effect on Company and its subsidiaries, taken
as a whole, or prevent Company from consummating the transactions contemplated
hereby.

                  (e) None of Company, any of its affiliates or anyone acting on
its or their behalf, has issued, sold, or offered any security of Company to any
person under circumstances that would cause the issuance and sale of Option I
Shares or Option II Shares, as contemplated by this Agreement, to be subject to
the registration requirements of the Securities Act as in effect on the date
hereof, and, assuming the representations and warranties of Holders contained in
Section 7(c) are true and correct, the issuance, sale and delivery of the Option
I Shares or Option II Shares hereunder would be exempt from the registration and
prospectus delivery requirements of the Securities Act, as in effect on the date
hereof (and Company shall not take any action



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which would cause the issuance, sale and delivery of the Option I Shares or
Option II Shares not to be exempt from such requirements).

         7. Representations and Warranties of Holders. Each Holder represents
and warrants to Company as follows:

                  (a) Each Holder is a limited liability company duly organized,
validly existing under the laws of the State of Delaware and has all requisite
power and authority to execute and deliver this Agreement and to consummate the
transactions contemplated hereby. Each Holder has duly and validly executed this
Agreement and, assuming the due authorization, execution and delivery hereof by
the Company, this Agreement constitutes a legal, valid and binding obligation of
Holders, enforceable against Holders in accordance with its terms, except that
(i) such enforcement may be subject to applicable bankruptcy, insolvency,
reorganization, moratorium or other similar laws, now or hereafter in effect,
affecting creditors' rights generally and (ii) the remedy of specific
performance and injunctive and other forms of equitable relief may be subject to
equitable defenses and to the discretion of the court before which any
proceeding therefor may be brought.

                  (b) Neither the execution and delivery of this Agreement, the
consummation by each Holder of the transactions contemplated hereby, nor the
compliance by Holder with any of the provisions hereof will (i) conflict with,
or result in a breach of, any provision of its organizational documents, (ii)
require any permit, authorization, consent or approval of, or filing with, or
notification to (except for permits, authorizations, consents, approvals or
filings under the Exchange Act, the Securities Act, the HSR Act, the
Communications Act, or state public utility or public service laws (if any))
with, or notification to, any Governmental Authority, (iii) conflict with, or
result in a violation or breach of, or constitute (with or without due notice or
lapse of time or both) a default (or give rise to any right of termination,
cancellation or acceleration) under any of the terms, conditions or provisions
of any material document, material agreement, or other material instrument to
which any Holder is a party or by which any Holder is bound, (iv) require any
consent, authorization, waiver or approval of any person other than a
Governmental Authority, or (vi) violate any order, writ, injunction, decree or
law applicable to Holders, excluding from the foregoing clauses (ii)-(vi) such
violations, breaches or defaults which would not, individually or in the
aggregate, have a material adverse effect on Holders and its subsidiaries, taken
as a whole, or prevent Holders from consummating the transactions contemplated
hereby.

                  (c) Any Common Stock acquired pursuant to this Agreement will
be acquired for Holder's own account (or for accounts over which it exercises
investment authority), for investment purposes only, and will not be acquired
with a view to the public distribution thereof in violation of any applicable
provision of the Securities Act.

         8. No Impairment. The Company shall not by any action including,
without limitation, amending its certificate of incorporation or through any
reorganization, transfer of assets, consolidation, merger, dissolution, issue or
sale of securities or any other voluntary action, avoid or seek to avoid the
observance or performance of any of the terms of the Options, but will at all
times in good faith assist in the carrying out of all such terms and in the
taking of all such actions as may be necessary or appropriate to protect the
rights of the Holders against impairment.



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Without limiting the generality of the foregoing, the Company will (a) not,
directly or indirectly, increase the par value of any shares of Common Stock
receivable upon the exercise of the Options above the amount payable therefor
upon such exercise immediately prior to such increase in par value, (b) take all
such action as may be necessary or appropriate in order that the Company may
validly and legally issue fully paid and nonassessable shares of Common Stock
upon the exercise of this the Options, and (c) use its commercially reasonable
best efforts to obtain all such authorizations, exemptions or consents from any
public regulatory body having jurisdiction thereof as may be necessary to enable
the Company to perform its obligations under the Options.

         9. Adjustments Generally. The Exercise Price and the number of shares
of Common Stock (or other securities or property) issuable upon exercise of each
of the Options shall be subject to adjustment from time to time upon the
occurrence of certain events, as provided in this Section 9.

                  (a) Common Stock Reorganization. If the Company shall after
the date hereof subdivide its outstanding shares of Common Stock into a greater
number of shares or consolidate its outstanding shares of Common Stock into a
smaller number of shares (any such event being called a "Common Stock
Reorganization"), then (i) the Exercise Price shall be adjusted, effective
immediately after the record date at which the holders of shares of Common Stock
are determined for purposes of such Common Stock Reorganization, to a price
determined by multiplying the Exercise Price in effect immediately prior to such
record date by a fraction, the numerator of which shall be the number of shares
of Common Stock outstanding on such record date before giving effect to such
Common Stock Reorganization and the denominator of which shall be the number of
shares of Common Stock outstanding after giving effect to such Common Stock
Reorganization, and (ii) the number of shares of Common Stock subject to
purchase upon exercise of each of the Options respectively shall be adjusted,
effective at such time, to a number determined by multiplying the number of
shares of Common Stock subject to purchase immediately before such Common Stock
Reorganization by a fraction, the numerator of which shall be the number of
shares outstanding after giving effect to such Common Stock Reorganization and
the denominator of which shall be the number of shares of Common Stock
outstanding immediately before such Common Stock Reorganization.

                  (b) Common Stock Distribution.

                           (i) Subject to the last sentence of this paragraph,
if the Company shall after the date hereof issue or otherwise sell or distribute
any shares of Common Stock, otherwise than pursuant to a Common Stock
Reorganization (any such event, including any event described in paragraphs (ii)
and (iii) below, being herein called a "Common Stock Distribution"), if such
Common Stock Distribution shall be for a consideration per share less than the
Fair Market Value per share of outstanding Common Stock of the Company on the
date of such Common Stock Distribution, or on the first date of the announcement
of such Common Stock Distribution (whichever is less), then, effective upon such
Common Stock Distribution, the number of shares of Common Stock purchasable upon
exercise of each of the Options respectively shall be adjusted by multiplying
the number of shares of Common Stock subject to purchase upon exercise of each
of the Options by a fraction, the numerator of which shall be the total number
of shares of Common Stock outstanding (and issuable upon exercise or conversion
of outstanding



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options, warrants and convertible securities) immediately prior to such Common
Stock Distribution plus the number of shares of Common Stock issued (or deemed
to be issued pursuant to paragraphs (ii) and (iii) below) in such Common Stock
Distribution and the denominator of which shall be an amount equal to the sum of
(A) the number of shares of Common Stock outstanding (and issuable upon exercise
or conversion of outstanding options, warrants and convertible securities)
immediately prior to such Common Stock Distribution, plus (B) the number of
shares of Common Stock which the aggregate consideration, if any, received by
the Company (determined as provided below) for such Common Stock Distribution
would buy at the Fair Market Value thereof, as of the date immediately prior to
such Common Stock Distribution or as of the date immediately prior to the date
of announcement of such Common Stock Distribution (whichever is less). In the
event of any such adjustment, the exercise price for each of the Options shall
be adjusted to a number determined by dividing the exercise price immediately
prior to such Common Stock Distribution by the fraction used for purposes of the
aforementioned adjustment. The provisions of this paragraph (i), including by
operation of paragraph (ii) or (iii) below, shall not operate to increase the
Exercise Price or to reduce the number of shares of Common Stock subject to
purchase upon exercise of each of the Options.

                           (ii) If the Company shall after the date hereof
issue, sell, distribute or otherwise grant in any manner (whether directly or by
assumption in a merger or otherwise) any rights to subscribe for or to purchase,
or any warrants or options for the purchase of, Common Stock or any stock or
securities convertible into or exchangeable for Common Stock (such rights,
warrants or options being herein called "Warrants" and such convertible or
exchangeable stock or securities being herein called "Convertible Securities"),
whether or not such Warrants or the rights to convert or exchange any such
Convertible Securities are immediately exercisable, and the price per share for
which Common Stock is issuable upon the exercise of such Warrants or upon
conversion or exchange of such Convertible Securities (determined by dividing
(x) the aggregate amount, if any, received or receivable by the Company as
consideration for the granting of such Warrants, plus the minimum aggregate
amount of additional consideration payable to the Company upon the exercise of
all such Warrants, plus, in the case of Warrants to acquire Convertible
Securities the minimum aggregate amount of additional consideration, if any,
payable upon the issuance or sale of such Convertible Securities and upon the
conversion or exchange thereof, by (y) the total maximum number of shares of
Common Stock issuable upon the exercise of such Warrants or upon the conversion
or exchange of all such Convertible Securities issuable upon the exercise of
such Warrants) shall be less than the Fair Market value per share of outstanding
Common Stock of the Company on the date of granting such Warrants or on the
first date of announcement thereof (whichever is less), then for purposes of
paragraph (i) above the total maximum number of shares of Common Stock issuable
upon the exercise of such Warrants or upon conversion or exchange of the total
maximum amount of such Convertible Securities issuable upon the exercise of such
Warrants shall be deemed to have been issued as of the date of granting of such
Warrants and thereafter shall be deemed to be outstanding and the Company shall
be deemed to have received as consideration such price per share, determined as
provided above, therefor. Except as otherwise provided in paragraph (iv) below,
no additional adjustment to the number of shares of Common Stock purchasable
upon the exercise either of the Options or of the Exercise Price shall be made
upon the actual exercise of such Warrants or upon conversion or exchange of such
Convertible Securities.



                                       10
<PAGE>   11

                           (iii) If the Company shall after the date hereof
issue, sell or otherwise distribute or grant (whether directly or by assumption
in a merger or otherwise) any Convertible Securities, whether or not the rights
to exchange or convert thereunder are immediately exercisable, and the price per
share for which Common Stock is issuable upon such conversion or exchange
(determined by dividing (x) the aggregate amount received or receivable by the
Company as consideration for the issue, sale or distribution of such Convertible
Securities, plus the minimum aggregate amount of additional consideration, if
any, payable to the Company upon the conversion or exchange thereof, by (y) the
total maximum number of shares of Common Stock issuable upon the conversion or
exchange of all such Convertible Securities) shall be less than the Fair Market
Value per share of outstanding Common Stock of the Company on the date of such
issue, sale or distribution or on the first date of announcement thereof
(whichever is less), then, for purposes of paragraph (i) above, the total
maximum number of shares of Common Stock issuable upon conversion or exchange of
all such Convertible Securities shall be deemed to have been issued as of the
date of the issue, sale or distribution of such Convertible Securities and
thereafter shall be deemed to be outstanding and the Company shall be deemed to
have received as consideration such price per share, determined as provided
above, therefor. Except as otherwise provided in paragraph (iv) below, no
additional adjustment to the number of shares of Common Stock purchasable upon
exercise of either of the Options or of the Exercise Price shall be made upon
the actual conversion or exchange of such Convertible Securities.

                           (iv) If the purchase price provided for in any
Warrant referred to in paragraph (ii) above, the additional consideration, if
any, payable upon the conversion or exchange of any Convertible Securities
referred to in paragraph (ii) or (iii) above, or the rate at which any
Convertible Securities referred to in paragraph (ii) or (iii) above are
convertible into or exchangeable for Common Stock shall change at any time
(other than under or by reason of provisions designed to protect against, and
having the effect of protecting against, dilution upon an event which results in
a related adjustment pursuant to this Section 9), then the number of shares of
Common Stock purchasable upon exercise each of the Options and the Exercise
Price then in effect shall forthwith be readjusted (effective only with respect
to any exercise of each of the Options after such readjustment) to the number of
shares of Common Stock purchasable upon exercise of each of the Options and the
Exercise Price which would then be in effect had the adjustment made upon the
issue, sale, distribution or grant of such Warrants or Convertible Securities
been made based upon such changed purchase price, additional consideration or
conversion rate, as the case may be; provided, however, that such readjustment
shall give effect to such change only with respect to such Warrants and
Convertible Securities as then remain outstanding. If, at any time after any
adjustment of the number of shares of Common Stock purchasable upon exercise of
each of the Options or the Exercise Price shall have been made pursuant to this
Section 9 on the basis of the issuance of any Warrants or Convertible Securities
or after any new adjustments to the number of shares of Common Stock purchasable
upon exercise of each of the Option or the Exercise Price shall have been made
pursuant to this Section 9, the right of conversion, exercise or exchange in
such Convertible Securities shall expire or terminate, and the right of
conversion, exercise or exchange in respect of a portion of such Warrants or
Convertible Securities shall not have been exercised, such previous adjustment
shall be rescinded and annulled. Thereupon, a recomputation shall be made of the
effect of such Warrants or Convertible Securities on the basis of treating the
number of shares of Common Stock, if any, theretofore actually issued or
issuable pursuant to the previous exercise of such



                                       11
<PAGE>   12

right of conversion, exercise or exchange as having been issued on the date or
dates of such conversion, exercise or exchange and for the consideration
actually received and receivable therefor, and treating any such Warrants or
Convertible Securities which then remain outstanding as having been granted or
issued immediately after the time of any such issuance for the consideration per
share for which shares of Common Stock are issuable under such Warrants or
Convertible Securities; and, if and to the extent called for by the foregoing
provisions of this Section 9, on the basis aforesaid, a new adjustment of the
number of shares of Common Stock purchasable upon exercise of each of the
Options and the Exercise Price shall be made, which new adjustment shall
supersede (effective only with respect to any exercise of each of the Options
after such readjustment) the previous adjustment so rescinded and annulled.

                           (v) If the Company shall after the date hereof pay a
dividend or make any other distribution upon any capital stock of the Company
payable in Common Stock, Warrants or Convertible Securities, then, for purposes
of paragraph (i) above, such Common Stock, Warrants or Convertible Securities,
as the case may be, shall be deemed to have been issued or sold without
consideration.

                           (vi) If any shares of Common Stock, Warrants or
Convertible Securities shall be issued, sold or distributed for cash, the
consideration received therefor shall be deemed to be the amount received by the
Company therefor, after deduction therefrom of any expenses incurred and any
underwriting commissions or concessions paid or allowed by the Company in
connection therewith. If any shares of Common Stock, Warrants or Convertible
Securities shall be issued, sold or distributed for property or assets other
than cash, then the amount of such property and assets shall be deemed to be the
Fair Market Value of such property and assets after deduction of any expenses
incurred or allowed by the Company in connection therewith. If any shares of
Common Stock, Warrants or Convertible Securities shall be issued in connection
with any merger in which the Company is the surviving corporation, the amount of
consideration therefor shall be deemed to be the Fair Market Value of such
portion of the assets and business of the nonsurviving corporation as shall be
attributable to such Common Stock, Warrants or Convertible Securities, as the
case may be.

                           (vii) If the Company shall take a record of the
holders of the Common Stock for the purpose of entitling them to receive a
dividend or other distribution payable in Common Stock, Warrants or Convertible
Securities or to subscribe for or purchase Common Stock, Warrants or Convertible
Securities, then such record date shall be deemed to be the date of the issue,
sale, distribution or grant of the shares of Common Stock deemed to have been
issued or sold upon the declaration of such dividend or the making of such other
distribution or the date of the granting of such right of subscription or
purchase, as the case may be.

                           (viii) For purposes of determining whether any
adjustment is required pursuant to this Section 9, any security of the Company
having rights substantially equivalent to the Common Stock as to dividends or
upon liquidation, dissolution or winding up of the Company shall be treated as
if such security were Common Stock.

                  (c) Dividends. If the Company shall after the date hereof
issue or distribute to all or substantially all holders of shares of Common
Stock evidences of indebtedness, any other securities of the Company or any
cash, property or other assets, and if such issuance or



                                       12
<PAGE>   13

distribution does not constitute a Common Stock Reorganization or a Common Stock
Distribution (any such nonexcluded event being herein called a "Dividend"), then
(i) the number of shares of Common Stock subject to purchase upon exercise of
each of the Options shall be increased (but not decreased), effective
immediately after the record date at which the holders of shares of Common Stock
are determined for purposes of such Dividend, to a number determined by
multiplying the number of shares of Common Stock subject to purchase immediately
before such Dividend by a fraction, the numerator of which shall be the Fair
Market Value per share of outstanding Common Stock on such record date and the
denominator of which shall be the Fair Market Value per share of outstanding
Common Stock of the Company on such record date less the then Fair Market Value
of the evidences of indebtedness, securities, cash, or property or other assets
issued or distributed in such Dividend with respect to one share of Common
Stock, and (ii) the Exercise Price shall be decreased (but not increased) to a
price determined by multiplying the Exercise Price then in effect by a fraction,
the numerator of which shall be the number of shares of Common Stock subject to
purchase upon exercise of the applicable Option immediately before such Dividend
and the denominator of which shall be the number of shares of Common Stock
subject to purchase upon exercise of the applicable Option immediately after
such Dividend. If after the date hereof the Company repurchases shares of Common
Stock for a per share consideration which exceeds the Fair Market Value (as
calculated immediately prior to such repurchase), then the number of shares of
Common Stock purchasable upon exercise of the applicable Option and the Exercise
Price shall be adjusted in accordance with the foregoing provisions, as if, in
lieu of such repurchases, the Company had (x) distributed a Dividend having a
Fair Market Value equal to the Fair Market Value of all property and cash
expended in the repurchases, and (y) effected a reverse split of the Common
Stock in the proportion required to reduce the number of shares of Common Stock
outstanding from (1) the number of such shares outstanding immediately before
such first repurchase to (2) the number of such shares outstanding immediately
following all the repurchases.

                  (d) Capital Reorganization. If after the date hereof there
shall be any consolidation or merger to which the Company is a party, other than
a consolidation or a merger in which the Company is the continuing corporation
and which does not result in any reclassification of, or change (other than a
Common Stock Reorganization or a change in par value), in, outstanding shares of
Common Stock, or any sale or conveyance of the property of the Company as an
entirety or substantially as an entirety (any such event being called a "Capital
Reorganization"), then, effective upon the effective date of such Capital
Reorganization, the Holders shall have the right to purchase, upon exercise of
each of the Options, the kind and amount of shares of stock and other securities
and property (including cash) which the Holders would have owned or have been
entitled to receive after such Capital Reorganization if each of the Options had
been exercised immediately prior to such Capital Reorganization.

                  (e) Certain Other Events. If any event occurs after the date
hereof as to which the foregoing provisions of this Section 9 are not strictly
applicable or, if strictly applicable, would not, in the good faith judgment of
the Board of Directors of the Company, fairly protect the rights of the Holders
in accordance with the essential intent and principles of this Agreement, then
such Board shall make such adjustments in the application of such provisions, in
accordance with such essential intent and principles, as shall be reasonably
necessary, in the good faith opinion of such Board, to protect such purchase
rights as aforesaid, but in no event shall any such adjustment have the effect
of increasing the Exercise Price or decreasing the number of



                                       13
<PAGE>   14

shares of Common Stock subject to purchase upon exercise of each of the Options,
or otherwise adversely affect the rights of the Holders hereunder.

                  (f) Adjustment Rules.

                           (i) Any adjustments pursuant to this Section 9 shall
be made successively whenever an event referred to herein shall occur.

                           (ii) If the Company shall set a record date to
determine the holders of shares of Common Stock for purposes of a Common Stock
Reorganization, Common Stock Distribution, Dividend or Capital Reorganization,
and shall legally abandon such action prior to effecting such action, then no
adjustment shall be made pursuant to this Section 9 in respect of such action.

                           (iii) No adjustment in the amount of the Exercise
Price shall be made hereunder unless such adjustment increases or decreases such
amount or price by one cent or more, but any such lesser adjustment shall be
carried forward and shall be made at the time and together with the next
subsequent adjustment which together with any adjustments so carried forward
shall serve to adjust such Exercise Price by one cent or more.

                           (iv) No adjustment in the Exercise Price shall be
made hereunder if such adjustment would reduce the exercise price to an amount
below par value of the Common Stock, which par value shall initially be $.01 per
share of Common Stock.

                           (v) In computing adjustments under this Section 9 or
the number of shares that may be purchased upon exercise of either of the
Options, fractional interests in Common Stock shall be taken into account to the
nearest 1/10th of a share, and adjustments in the Exercise Price shall be made
to the nearest $.01.

                           (vi) No adjustment shall be made under this Section
9, (A) upon the exercise of any warrants, options or convertible securities
(other than the Series C Preferred Stock) issued and outstanding on the date
hereof in accordance with the terms of such securities as of such date; (B) upon
the grant or exercise of any stock or options which may hereafter be granted or
exercised under any employee or director benefit plan of the Company now
existing or to be implemented in the future, so long as the issuance of such
stock or options is approved by a majority of the non-employee members of the
Board of Directors of the Company or a majority of the members of a committee of
non-employee directors established for the purpose; (C) upon the issuance of the
Common Stock or Options in accordance with terms of the Purchase Agreement; (D)
upon the exercise of the Options; (E) the issuance of up to 13,250,000 shares of
Common Stock (or common-stock equivalent preferred stock that is convertible
into common stock) in connection with the exchange or conversion of the Series C
Preferred Stock; (F) the issuance contemporaneously with the closing under the
Purchase Agreement of up to an amount of shares of Common Stock equal to the
product of (1) two multiplied by (2) the number of shares of Common Stock
purchased by Holders pursuant to the Purchase Agreement, at a purchase price of
$2.19 per share; or (g) the issuance of the shares of Common Stock purchased by
Holders pursuant to the Purchase Agreement.



                                       14
<PAGE>   15

                  (g) Proceedings Prior to Any Action Requiring Adjustment. As a
condition precedent to the taking of any action which would require an
adjustment pursuant to this Section 9, the Company shall take any action which
may be necessary, including obtaining regulatory approvals or exemptions, in
order that the Company may thereafter validly and legally issue as fully paid
and nonassessable all shares of Common Stock which the Holders is entitled to
receive upon exercise of the Options.

                  (h) Notice of Adjustment. Not less than 10 nor more than 30
days prior to the record date or effective date, as the case may be, of any
action which requires or might require an adjustment or readjustment pursuant to
this Section 9, the Company shall give notice to the Holders of such event,
describing such event in reasonable detail and specifying the record date or
effective date, as the case may be, and, if determinable, the required
adjustment and the computation thereof. If the required adjustment is not
determinable at the time of such notice, the Company shall give notice to the
Holders of such adjustment and computation promptly after such adjustment
becomes determinable.

         10. Contest Rights. Upon each determination of Fair Market Value
hereunder (other than a determination relating solely to setting the value of
fractional shares), the Company shall promptly give notice thereof to the
Holders, setting forth in reasonable detail the calculation of such Fair Market
Value and the method and basis of determination thereof, as the case may be. If
the Holders shall disagree with such determination and shall, by notice to the
Company given within 15 days after the Company's notice of such determination,
elect to dispute such determination, such dispute shall be resolved in
accordance with the Appraisal Procedure.

         11. Legends.

         Upon issuance to Holders of any Option I Shares or Option II Shares
upon purchase thereof pursuant to this Agreement, such Option I Shares or Option
II Share shall be endorsed with a restrictive legend which shall read
substantially as follows:

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
                  ANY STATE SECURITIES OR BLUE SKY LAWS, AND MAY BE REOFFERED,
                  SOLD, OR TRANSFERRED ONLY IF SO REGISTERED OR IF AN EXEMPTION
                  FROM SUCH REGISTRATION IS AVAILABLE."

         12. Definitions.

         The following terms, as used in this Agreement, have the following
respective meanings:

         "Appraisal Procedure" means a procedure whereby two independent
appraisers, one chosen by the Company and one by the Holders, shall mutually
agree upon the determinations then the subject of appraisal. Each party shall
deliver a notice to the other appointing its appraiser within 15 days after the
Appraisal Procedure is invoked. If within 30 days after appointment of the two
appraisers they are unable to agree upon the amount in question, a third
independent appraiser shall be chosen within 10 days thereafter by the mutual
consent of such first two appraisers or, if such first two appraisers fail to
agree upon the appointment of a third



                                       15
<PAGE>   16


appraiser, such appointment shall be made by the American Arbitration
Association, or any organization successor thereto, from a panel of arbitrators
having experience in the appraisal of the subject matter to be appraised. The
decision of the third appraiser so appointed and chosen shall be given within 30
days after the selection of such third appraiser. The determination of the
appraisers or appraiser appointed hereunder shall be binding and conclusive on
the Company and the Holders. The costs of conducting any Appraisal Procedure
shall be borne by the Holders; provided however, the fees and expenses of the
Company of the Holders, of the appraisers appointed hereunder and of the
Appraisal Procedure shall be borne by the Company if such Appraisal Procedure
shall result in a determination that is disparate by 2% or more to the benefit
of Holders from the Company's initial determination.

         "Business Day" shall mean (a) if any class of Common Stock is listed or
admitted to trading on a national securities exchange, a day on which the
principal national securities exchange on which such class of Common Stock is
listed or admitted to trading is open for business or (b) if no class of Common
Stock is so listed or admitted to trading, a day on which any New York Stock
Exchange member firm is open for business.

         "Closing Price" with respect to any security on any day means (a) if
such security is listed or admitted for trading on a national securities
exchange, the reported last sales price regular way or, if no such reported sale
occurs on such day, the average of the closing bid and asked prices regular way
on such day, in each case as reported in the principal consolidated transaction
reporting system with respect to securities listed on the principal national
securities exchange on which such class of security is listed or admitted to
trading, or (b) if such security is not listed or admitted to trading on any
national securities exchange, the last quoted sales price, or, if not so quoted,
the average of the high bid and low asked prices in the over-the-counter market
on such day as reported by NASDAQ or any comparable system then in use or, if
not so reported, as reported by any New York Stock Exchange member firm
reasonably selected by the Company for such purpose.

         "Exercise Price" means respectively as to each of the Options, the
exercise price respectively specified herein for each of the Options as such
exercise price may be adjusted from time to time as provided herein.

         "Fair Market Value" means the fair market value of the business or
property in question, as determined in good faith by the Board of Directors of
the Company, provided, however, that the Fair Market Value of any security for
which a Closing Price is available shall be the Market Price of such security.

         "Market Price", with respect to any security on any day means the
average of the daily Closing-Prices of a share or unit of such security for the
10 consecutive Business Days ending on the most recent Business Day for which a
Closing Price is available; provided, however, that in the event that, in the
case of Common Stock, the Market Price is determined during a period following
the announcement by the Company of (A) a dividend or distribution of Common
Stock, or (B) any subdivision, combination or reclassification of Common Stock
and prior to the expiration of 10 Business Days after the ex-dividend date for
such dividend or distribution, or the record date for such subdivision,
combination or reclassification, then, and in each such case, the



                                       16
<PAGE>   17

Market Price shall be appropriately adjusted to reflect the current market price
per share equivalent of Common Stock.

         "NASDAQ" means The National Association of Securities Dealers, Inc.
Automated Quotation System.

         13. No Rights or Liabilities as Stockholders. Nothing contained in this
Agreement shall be construed as conferring upon the Holders hereof any rights as
a stockholders of the Company or as imposing any liabilities on such Holders to
purchase any securities or as a stockholders of the Company, whether such
liabilities are asserted by the Company or by creditors or stockholders of the
Company or otherwise.

         14. Specific Enforcement. The parties hereto agree that the remedy at
law for any breach of this Agreement may be inadequate, and that as between the
Company and the Holders, any party by whom this Agreement is enforceable shall
be entitled to specific performance in addition to any other appropriate relief
or remedy. Such party may, in its sole discretion, apply to a court of competent
jurisdiction for specific performance or injunctive or such other relief as such
court may deem just and proper in order to enforce this Agreement as between the
Company and the Holders, or prevent any violation hereof, and, to the extent
permitted by applicable law as between the Company and the Holders, each party
waives any objection to the imposition of such relief.

         15. Expenses. Except as otherwise provided herein, all costs and
expenses incurred in connection with this Agreement and the transactions
contemplated hereby shall be paid by the party incurring such expenses.

         16. Amendment. This Agreement may not be modified, amended, altered or
supplemented except upon the execution and delivery of a written agreement
executed by the parties hereto.

         17. Notices. All notices which are permitted or required under this
Agreement shall be in writing and shall be deemed given (a) when delivered
personally, (b) if by fax upon transmission with confirmation of receipt by the
receiving party's facsimile terminal, (c) if sent by documented overnight
delivery service on the date delivered or (d) if sent by mail, five (5) business
days after being mailed by registered or certified mail, postage prepaid,
addressed as follows, or to such other person as may be designated by notice to
the other party:

                  If to a Holder:

                           HMTF Bridge MC I, LLC
                           HM 4-EQ Metrocall Coinvestors, LLC
                           HM 4-SBS Metrocall Coinvestors, LLC
                           HM PG-IV Metrocall, LLC
                           HM4 Metrocall Qualified Fund, LLC
                           HM4 Metrocall Private Fund
                           c/o Hicks, Muse, Tate & Furst Incorporated
                           1325 Avenue of the Americas
                           25th Floor



                                       17
<PAGE>   18

                           New York, NY  10019
                           Attn:  Michael Levitt
                           Telephone:  (212) 424-1400
                           Fax:  (212) 424-1450


                  with a copy (which shall not constitute notice) to:

                           Vinson & Elkins L.L.P.
                           1325 Avenue of the Americas
                           17th Floor
                           New York, NY  10019
                           Attn:  Eric S. Shube
                           Telephone:  (917) 206-8005
                           Fax:  (917) 206-8100


                  If to the Company:

                           Metrocall, Inc.
                           6677 Richmond Highway
                           Alexandria, VA  22306
                           Attention:  Vincent D. Kelly, Chief Financial
                                Officer and Treasurer
                           Fax: (703) 768-9625

                  with copy (which shall not constitute notice) to:

                           Wilmer, Cutler & Pickering
                           2445 M Street, N.W.
                           Washington, D.C.  20037
                           Attention:  Thomas W. White
                           Fax:  (202) 663-6363

         18. Entire Agreement. This Agreement (together with the Purchase
Agreement and any other documents and instruments referred to herein)
constitutes the entire agreement and supersedes all other prior agreements and
understandings, both written and oral, between the parties, with respect to the
subject matter hereof.

         19. Successors and Assigns. This Agreement shall not be assigned, by
operation of law or otherwise, without the prior written consent of the other
party hereto, except that the Holders may assign its rights hereunder, in whole
or in part, to an affiliate. This Agreement will be binding upon, inure to the
benefit of and be enforceable by each party and such party's respective heirs,
beneficiaries, executors, representatives and permitted assigns.

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



                                       18
<PAGE>   19


         21. Governing Law. This Agreement shall be governed in all respects,
including validity, interpretation and effect, by the laws of the State of
Delaware (without giving effect to the provisions thereof relating to conflicts
of law).

         22. Capitalized Terms. Capitalized Terms used herein but not defined
shall have the meanings set forth in the Purchase Agreement.



                                           [Signature Page Follows]



                                       19
<PAGE>   20

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



                                             METROCALL, INC.


                                             By: /s/ Steven D. Jacoby
                                                --------------------------------
                                                Name:  Steven D. Jacoby
                                                Title: Executive Vice President



                                             HMTF BRIDGE MC I, LLC


                                             By: /s/ David W. Knickel
                                                --------------------------------
                                                Name:  David W. Knickel
                                                Title:    Vice President



                                             HM 4-EQ METROCALL COINVESTORS, LLC


                                             By: /s/ David W. Knickel
                                                --------------------------------
                                                Name:  David W. Knickel
                                                Title:    Vice President



                                             HM 4-SBS METROCALL COINVESTORS, LLC


                                             By: /s/ David W. Knickel
                                                --------------------------------
                                                Name:  David W. Knickel
                                                Title:    Vice President



                                             HM PG-IV METROCALL, LLC


                                             By: /s/ David W. Knickel
                                                --------------------------------
                                                Name:  David W. Knickel
                                                Title:    Vice President



                  Signature Page 1 of 2 of the Option Agreement

<PAGE>   21

                                             HM4 METROCALL QUALIFIED FUND, LLC


                                             By: /s/ David W. Knickel
                                                --------------------------------
                                                Name:  David W. Knickel
                                                Title:    Vice President


                                             HM4 METROCALL PRIVATE FUND, LLC


                                             By: /s/ David W. Knickel
                                                --------------------------------
                                                Name:  David W. Knickel
                                                Title:    Vice President



                  Signature Page 2 of 2 of the Option Agreement

<PAGE>   22

                                    EXHIBIT A

                                    Interests

<TABLE>
<CAPTION>

Holder                                      Percentage                Number of      Number of          Number of
------                                      ----------                Shares         Shares             Shares
                                                                      Pursuant       Pursuant           Pursuant
                                                                      To Option I    To Option II(1)    To Option II(2)
                                                                      -----------    ---------------    ---------------
<S>                                         <C>                      <C>              <C>               <C>
HMTF Bridge MC I, LLC                       50%                      4,166,666        6,250,000         10,416,666

HM4-EQ Metrocall Coinvestors, LLC           1.337099% of 50%            55,712           83,568            139,280

HM4-SBS Metrocall Coinvestors, LLC          2.179044 of 50%             90,794          136,191            226,984

HM PG-IV Metrocall, LLC                     4.844421% of 50%           201,851          302,777            504,628

HM4 Metrocall Qualified Fund, LLC           90.994792% of 50%        3,791,450        5,687,174          9,478,624

HM4 Metrocall Private Fund, LLC             .0644644% of 50%            26,860           40,290             67,150
</TABLE>


--------
(1) Assumes Option I has been previously exercised.

(2) Assumes Option I has not been previously exercised.


Exhibit A