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                                                                  EXECUTION COPY


                          REGISTRATION RIGHTS AGREEMENT


            REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of
November 18, 2003, by and between Metrocall Holdings, Inc., a Delaware
corporation, with headquarters located at 6677 Richmond Highway, Alexandria,
Virginia 22306 (the "COMPANY"), and WebLink Wireless I, L.P., a Texas limited
partnership, with headquarters located at 3333 Lee Parkway, Suite 100, Dallas,
Texas 75219 (the "HOLDER").

            WHEREAS:

            A. The Common Stock of the Company, $.01 par value per share (the
"COMMON STOCK") is registered pursuant to Section 12(g) of the Securities Act of
1933, as amended (the "1933 ACT");

            B. Pursuant to the Asset Purchase Agreement by and among the
Company, Metrocall, Inc. a Delaware corporation ("Metrocall"), the Holder, and
WebLink Wireless, Inc., a Delaware corporation ("WebLink Wireless"), dated of
even date herewith (the "ASSET PURCHASE AGREEMENT"), the Company has agreed,
upon the terms and subject to the conditions of the Asset Purchase Agreement, to
issue and sell to the Holder 500,000 shares of the Common Stock (the "NEW COMMON
SHARES") and a warrant (the "INITIAL WARRANT") to purchase 25,000 shares of
Common Stock;

            C. Pursuant to the Asset Purchase Agreement and the Management and
Spectrum Lease Agreement, by and among the Company, Metrocall, PageMart II
Holdings LLC and PageMart PCS Holdings LLC ("Licensees"), each a Delaware
limited liability company, the Holder, dated of even date herewith (the
"MANAGEMENT AGREEMENT"), the Company has agreed to issue and sell to the Holder
an additional warrant (the "LICENSE WARRANT", and together with the Initial
Warrant, the "WARRANTS") to purchase 100,000 shares of Common Stock (the
aggregate 125,000 shares of Common Stock issuable pursuant to the Warrants are
hereinafter referred to as the "WARRANT SHARES", and the New Common Shares and
the Warrant Shares together are hereinafter referred to as the "Shares");

            D. To induce the Holder to execute and deliver the Asset Purchase
Agreement, the Company has agreed to provide certain registration rights for the
New Common Shares and the Warrant Shares under the 1933 Act, and the rules and
regulations thereunder, and applicable state securities laws;

            NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and the
Holder hereby agree as follows:

      1.    DEFINITIONS.

            As used in this Agreement, the following terms shall have the
following meanings:
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            a. "INVESTOR" means the Holder and any transferee of the New Common
Shares or Warrant Shares held by the Holder thereof to whom the Holder assigns
its rights under this Agreement and who agrees to become bound by the provisions
of this Agreement in accordance with Section 9.

            b. "PERSON" means a corporation, a limited liability company, an
association, a partnership, an organization, a business, an individual, an
entity, a governmental or political subdivision thereof or a governmental
agency.

            c. "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing one or more Registration
Statements in compliance with the 1933 Act and pursuant to Rule 415 under the
1933 Act or any successor rule providing for offering securities on a continuous
basis ("RULE 415"), and the declaration or ordering of effectiveness of such
Registration Statement(s) by the United States Securities and Exchange
Commission (the "SEC").

            d. "REGISTRABLE SECURITIES" means (i) the New Common Shares, (ii)
the Warrant Shares issued or issuable upon exercise of the Warrants, and (iii)
any shares of capital stock issued or issuable, from time to time, with respect
to the New Common Shares, the Warrant Shares or the Warrants as a result of any
reclassification, share combination, share subdivision, stock split, share
dividend, merger, consolidation or similar transaction or event or otherwise as
a distribution on, in exchange for or with respect to any of the foregoing, in
each case held at the relevant time by an Investor.

            e. "REGISTRATION STATEMENT" means a registration statement of the
Company filed under the 1933 Act.

      Capitalized terms used herein and not otherwise defined herein shall have
the respective meanings set forth in the Asset Purchase Agreement.

      2.    REGISTRATION.

            a. Mandatory Registration. Subject to Section 2(b), the Company
shall use its best efforts to prepare and file with the SEC as soon as
practicable, but in no event, subject to Section 2(b), more than 30 days, after
the Initial Closing Date a Registration Statement or Registration Statements (as
is necessary) on Form S-2 (or, if such form is unavailable for such a
registration, on Form S-1 or such other form as is available for such a
registration), covering the resale of all of the Registrable Securities or the
distribution of Registrable Securities to creditors and equityholders of the
Holder or WebLink Wireless, which Registration Statement(s) shall state that, in
accordance with Rule 416 promulgated under the 1933 Act, such Registration
Statement(s) also covers such indeterminate number of additional shares of
Common Stock as may become issuable upon exercise of the Warrants to prevent
dilution resulting from stock splits, stock dividends or similar transactions.
The Company shall use its best efforts to cause any such Registration
Statement(s) to become effective 120 days following the date hereof.

            b. Postponement. (i) The Company shall be entitled to postpone
filing of the Registration Statement pursuant to Section 2(a) and/or to require
the Investor to discontinue the disposition of its securities covered by such
Registration Statement(s), as applicable, during any


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Blackout Period (as defined below) (x) if the Board of Directors of the Company
determines in good faith that effecting such a registration or continuing such
disposition at such time would have a material adverse effect upon a proposed
sale of all (or substantially all) of the assets of the Company or a merger,
reorganization, recapitalization or similar current transaction materially
affecting the capital structure or equity ownership of the Company, or (y) if
the Company is in possession of material information which the Board of
Directors of the Company determines in good faith after consultation with
outside counsel is not in the best interests of the Company to disclose in a
registration statement at such time; provided, however, that the Company may
only delay filing of the Registration Statement pursuant to this Section 2(b)
only for a reasonable period of time not to exceed 90 days in any 12 month
period and may require the Investor to discontinue the disposition of its
securities covered by such Registration Statement pursuant to this Section 2(b)
only for a reasonable period of time not to exceed a total of 135 days in any 12
month period (or, in each case, such earlier time as such transaction is
consummated or no longer proposed or the material information has been made
public) (the "BLACKOUT PERIOD"). Notwithstanding anything herein to the
contrary, the Company may not delay filing of a Registration Statement or
require an Investor to discontinue the disposition of its securities more than
two times in any twelve month period. The Company shall promptly notify the
Investor in writing (a "BLACKOUT NOTICE") of any decision to postpone the filing
of the Registration Statement or to discontinue sales of Registrable Securities
covered by such Registration Statement pursuant to this Section 2(b) and, upon
the written request of an Investor, the Company shall provide such Investor with
a general statement in writing of the reason for such postponement, an
approximation of the anticipated delay and an undertaking by the Company to use
its reasonable best efforts to promptly notify the Investor as soon as the
Registration Statement may be filed or sales of Registrable Securities covered
by such Registration Statement may resume. In making any such determination to
initiate or terminate a Blackout Period, the Company shall not be required to
consult with or obtain the consent of any Investor, and any such determination
shall be the Company's sole responsibility. Each Investor shall treat all
notices or statements received from the Company pursuant to this Section 2(b) in
the strictest confidence and shall comply with the securities laws on account of
receipt or possession thereof and shall not disseminate such information.

            (ii) The Company represents and warrants that, except for the
transactions contemplated by the Asset Purchase Agreement, on the date hereof
and based upon the criteria set forth in this Agreement, the Company could not
issue a Blackout Notice to an Investor declaring that a Blackout Period is in
effect.

            c. Eligibility for Form S-2. The Company represents, warrants and
covenants that it meets the requirements for the use of Form S-2 for
registration of the sale by the Holder and any other Investor of the Registrable
Securities on and after the filing of the Registration Statement pursuant to
Section 2(a) of this Agreement and the Company has filed and shall file all
reports required to be filed by the Company with the SEC in a timely manner so
as to obtain and maintain such eligibility for the use of Form S-2. In the event
that Form S-2 is not available for sale by the Investors of the Registrable
Securities, then (i) the Company shall register the sale of the Registrable
Securities on Form S-1 or another appropriate form as soon as practicable, but
in any event, subject to Section 2(b), within 30 days of the date hereof, and
(ii) the Company shall undertake to register the Registrable Securities on Form
S-2 as soon as such form is available, provided that the Company shall maintain
the effectiveness of the Registration


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Statement then in effect until such time as a Registration Statement on Form S-2
covering the Registrable Securities has been declared effective by the SEC.

            d. Most Favored Nation Clause. Notwithstanding anything to the
contrary in this Agreement, the Company hereby covenants that the terms and
conditions applicable to the length and frequency of Blackout Periods shall be
at least as favorable as those offered by the Company to any other Person, and
this Agreement shall be amended as may be necessary to effect such covenant.

      3.    RELATED OBLIGATIONS.

            At such time as the Company is obligated to file a Registration
Statement with the SEC pursuant to Section 2(a), the Company will use its best
efforts to effect the registration of the Registrable Securities in accordance
with the intended method of disposition thereof and, pursuant thereto, the
Company shall have the following obligations:

            a. The Company shall prepare and file with the SEC such amendments
and supplements to the Registration Statement(s) and the prospectus(es) used in
connection therewith and take all such other actions as may be necessary to keep
the Registration Statement(s) current and effective pursuant to Rule 415 at all
times until the earlier of (i) the date on which the Investors may immediately
sell all of the Registrable Securities without volume limitation restrictions
pursuant to Rule 144(k) of the 1933 Act or (ii) the date on which (A) the
Investors shall have sold all the Registrable Securities, and no more
Registrable Securities are issuable pursuant to the Warrants, and (B) none of
the Warrants are outstanding (the "REGISTRATION PERIOD"). The Registration
Statement(s) (including any amendments or supplements thereto and prospectuses
contained therein) shall not contain any untrue statement of a material fact or
omit to state a material fact required to be stated therein, or necessary to
make the statements therein, in light of the circumstances in which they were
made, not misleading.

            b. The Company shall furnish promptly to each Investor whose
Registrable Securities are included in the Registration Statement(s) and its
legal counsel without charge such number of copies of the Registration
Statement(s) and prospectus(es), preliminary prospectus(es) in conformity with
the requirements of the 1933 Act and such other documents as such Investor may
reasonably request in order to facilitate the disposition of the Registrable
Securities owned by such Investor. The Company will use its reasonable best
efforts to respond to any and all comments received from the SEC, with a view
towards causing any Registration Statement or any amendment thereto to be
declared effective by the SEC as soon as practicable and shall promptly file an
acceleration request as soon as practicable following the resolution or
clearance of all SEC comments or, if applicable, following notification by the
SEC that the Registration Statement or any amendment thereto will not be subject
to review.

            c. The Company shall use its best efforts to promptly take such
action as may be necessary to qualify, or obtain, an exemption for the
Registrable Securities under such of the state securities laws of United States
jurisdictions as shall be necessary to qualify, or obtain an exemption for, the
sale of the Registrable Securities in states specified in writing by the
Investor; provided, however, that the Company shall not be required in
connection therewith or as a condition thereto to (x) qualify to do business in
any jurisdiction where it would not


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otherwise be required to qualify but for this Section 3(c), (y) subject itself
to general taxation in any such jurisdiction, or (z) file a general consent to
service of process in any such jurisdiction. The Company shall promptly notify
each Investor who holds Registrable Securities of the receipt by the Company of
any notification with respect to the suspension of the registration or
qualification of any of the Registrable Securities for sale under the securities
or "blue sky" laws of any jurisdiction in the United States or its receipt of
actual notice of the initiation or threatening of any proceeding for such
purpose.

            d. As promptly as practicable after becoming aware of such event,
the Company shall notify each Investor in writing of the happening of any event
as a result of which the prospectus included in a Registration Statement, as
then in effect, includes an untrue statement of a material fact or omission to
state a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading, and promptly prepare a supplement or amendment to the
Registration Statement to correct such untrue statement or omission, and deliver
ten (10) copies of such supplement or amendment to each Investor (or such other
number of copies as such Investor may reasonably request). The Company shall
also promptly notify each Investor in writing (i) when a prospectus or any
prospectus supplement or post-effective amendment has been filed, and when a
Registration Statement or any post-effective amendment has become effective
(notification of such effectiveness shall be delivered to each Investor promptly
by facsimile and by overnight mail), (ii) of any request by the SEC for
amendments or supplements to a Registration Statement or related prospectus or
related information, and (iii) of the Company's reasonable determination that a
post-effective amendment to a Registration Statement would be appropriate.

            e. The Company shall use its reasonable best efforts to prevent the
issuance of any stop order or other suspension of effectiveness of a
Registration Statement, or the suspension of the qualification of any of the
Registrable Securities for sale in any jurisdiction and, if such an order or
suspension is issued, to promptly obtain the withdrawal of such order or
suspension and to notify each Investor who holds Registrable Securities being
sold (and, in the event of an underwritten offering, the managing underwriters)
of the issuance of such order and the resolution thereof or its receipt of
actual notice of the initiation or threat of any proceeding for such purpose.

            f. The Company shall hold in confidence and not make any disclosure
of information concerning an Investor provided to the Company unless (i)
disclosure of such information is necessary to comply with federal or state
securities laws, (ii) the disclosure of such information is necessary to avoid
or correct a misstatement or omission in any Registration Statement, (iii) the
release of such information is ordered pursuant to a subpoena or other final,
non-appealable order from a court or governmental body of competent
jurisdiction, or (iv) such information has been made generally available to the
public other than by disclosure in violation of this or any other agreement. The
Company agrees that it shall, upon learning that disclosure of such information
concerning an Investor is sought in or by a court or governmental body of
competent jurisdiction or through other means, give prompt written notice to
such Investor and allow such Investor, at the Investor's expense, to undertake
appropriate action to prevent disclosure of, or to obtain a protective order
for, such information.


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            g. Notwithstanding anything to the contrary set forth herein or in
any other agreement to which the parties hereto are parties or by which they are
bound, the obligations of confidentiality contained herein and therein, as they
relate to the transactions contemplated by the Asset Purchase Agreement, shall
not apply to the tax structure or tax treatment of the transactions contemplated
by the Asset Purchase Agreement, and each party hereto (and any employee,
representative, or agent of any party hereto) may disclose to any and all
persons, without limitation of any kind, the tax structure and tax treatment of
the transactions contemplated by the Asset Purchase Agreement and all materials
of any kind (including opinions or other tax analysis) that are provided to such
party relating to such tax treatment and tax structure; provided, however, that
such disclosure shall not include the name (or other identifying information not
relevant to the tax structure or tax treatment) of any person and shall not
include information for which nondisclosure is reasonably necessary in order to
comply with applicable securities laws.

            h. The Company shall use its best efforts to cause all the
Registrable Securities covered by a Registration Statement to be listed or
quoted where securities of the same class or series issued by the Company are
then listed or quoted, as applicable, if the listing of such Registrable
Securities is then permitted under the rules of such exchange or quotation
system. The Company shall pay all fees and expenses in connection with
satisfying its obligation under this Section 3(h).

            i. The Company shall cooperate with the Investors who hold
Registrable Securities being offered to facilitate the timely preparation and
delivery of certificates (not bearing any restrictive legend) representing the
Registrable Securities to be offered pursuant to a Registration Statement and
enable such certificates to be in such denominations or amounts, as the case may
be, as the Investors may reasonably request and registered in such names as the
Investors may request.

            j. The Company shall take all other reasonable actions necessary to
expedite and facilitate disposition by the Investors of Registrable Securities
pursuant to a Registration Statement.

            k. The Company shall use its best efforts to cause the Registrable
Securities covered by the applicable Registration Statement to be registered
with or approved by such other governmental agencies or authorities as may be
necessary to consummate the disposition of such Registrable Securities.

            l. The Company shall otherwise use its reasonable best efforts to
comply with all applicable rules and regulations of the SEC in connection with
any registration hereunder.

      4.    OBLIGATIONS OF THE INVESTORS.

            a. At least ten (10) days prior to the first anticipated filing date
of the Registration Statement, the Company shall notify each Investor in writing
of the information the Company requires from each such Investor if such Investor
elects to have any of such Investor's Registrable Securities included in the
Registration Statement. It shall be a condition precedent to


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the obligations of the Company to complete the registration pursuant to this
Agreement with respect to the Registrable Securities of a particular Investor
that such Investor shall furnish to the Company such information as may be
requested in writing by the Company regarding itself, the Registrable Securities
held by it and the intended method of disposition of the Registrable Securities
held by it as shall be reasonably required to effect the registration of such
Registrable Securities and shall execute such documents in connection with such
registration as the Company may reasonably request.

            b. The Investor agrees that it will not effect any disposition of
the Registrable Securities that would constitute a sale within the meaning of
the 1933 Act except as contemplated in the Registration Statement referred to in
Section 2 or in accordance with the 1933 Act, and that it will promptly notify
the Company of any changes in the information set forth in the Registration
Statement regarding the Investor or its plan of distribution.

            c. Each Investor, by such Investor's acceptance of the Registrable
Securities, agrees to cooperate with the Company as reasonably requested by the
Company in connection with the preparation and filing of the Registration
Statement(s) hereunder unless such Investor has notified the Company in writing
of such Investor's election to exclude all of such Investor's Registrable
Securities from the Registration Statement.

            d. Each Investor agrees that, upon receipt of any notice from the
Company of the happening of any event of the kind described in Section 3(e) or
the first sentence of 3(d), such Investor will immediately discontinue
disposition of Registrable Securities pursuant to the Registration Statement(s)
covering such Registrable Securities until such Investor's receipt of the copies
of the supplemented or amended prospectus contemplated by Section 3(e) or the
first sentence of 3(d).

      5.    EXPENSES OF REGISTRATION.

            All reasonable expenses incurred by the Company in connection with
registrations, filings or qualifications pursuant to Sections 2 and 3,
including, without limitation, all registration, listing and qualifications
fees, printers and accounting fees, and fees and disbursements of counsel for
the Company shall be paid by the Company. Each Investor shall be responsible for
paying the underwriting commissions or brokerage fees, if any, and taxes of any
kind (including, without limitation, transfer taxes) applicable to any
disposition, sale or transfer of such Investor's Registrable Securities and any
fees and expenses of counsel or other advisors to the Investor.

      6.    INDEMNIFICATION.

            In the event any Registrable Securities are included in a
Registration Statement under this Agreement:

            a. The Company indemnifies and holds harmless each Investor who
holds such Registrable Securities, the directors, officers, partners, employees,
agents and each Person, if any, who controls any Investor within the meaning of
the 1933 Act or the Securities Exchange Act of 1934, as amended (the "1934
ACT"), (each, an "INDEMNIFIED PERSON"), against any losses, claims, damages,
liabilities, or expenses (collectively, "CLAIMS"), incurred in investigating,


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preparing or defending any action, claim, suit, inquiry, proceeding,
investigation or appeal taken from the foregoing by or before any court or
governmental, administrative or other regulatory agency, body or the SEC,
whether pending or threatened, whether or not an indemnified party is or may be
a party thereto ("INDEMNIFIED DAMAGES"), to which any of them may become subject
insofar as such Claims arise out of or are based upon: (i) any untrue statement
or alleged untrue statement of a material fact in a Registration Statement or
any post-effective amendment thereto or in any filing made in connection with
the qualification of the offering under the securities or other "blue sky" laws
of any jurisdiction in which Registrable Securities are offered, or the omission
or alleged omission to state a material fact required to be stated therein or
necessary to make the statements therein, in light of the circumstances under
which the statements therein were made, not misleading, (ii) any untrue
statement or alleged untrue statement of a material fact contained in any
preliminary prospectus if used prior to the effective date of such Registration
Statement, or contained in the final prospectus (as amended or supplemented, if
the Company files any amendment thereof or supplement thereto with the SEC) or
the omission or alleged omission to state therein any material fact necessary to
make the statements made therein, in light of the circumstances under which the
statements therein were made, not misleading, or (iii) any violation or alleged
violation by the Company of the 1933 Act, the 1934 Act, any other law,
including, without limitation, any state securities law, or any rule or
regulation thereunder relating to the offer or sale of the Registrable
Securities pursuant to a Registration Statement (the matters in the foregoing
clauses (i) through (iii) being, collectively, "VIOLATIONS"). Subject to the
restrictions set forth in Section 6(d) with respect to the number of legal
counsel, the Company shall reimburse each Indemnified Person as such expenses
are incurred and are due and payable, for any legal fees or other reasonable
expenses incurred by them in connection with investigating or defending any such
Claim. Notwithstanding anything to the contrary contained herein, the
indemnification agreement contained in this Section 6(a): (i) shall not apply to
a Claim arising out of or based upon a Violation which occurs in reliance upon
and in conformity with information furnished to the Company by any Indemnified
Person expressly for use in connection with the preparation of the Registration
Statement or any such amendment thereof or supplement thereto; (ii) with respect
to any preliminary prospectus, shall not inure to the benefit of any such person
from whom the person asserting any such Claim purchased the Registrable
Securities that are the subject thereof (or to the benefit of any person
controlling such person) if the untrue statement or omission of material fact
contained in the preliminary prospectus was corrected in the prospectus, as then
amended or supplemented, if such prospectus was timely made available by the
Company pursuant to Section 3(d), and the Indemnified Person was promptly
advised in writing not to use the incorrect prospectus prior to the use giving
rise to a Violation and such Indemnified Person, notwithstanding such advice,
used it; and (iii) shall not apply to amounts paid in settlement of any Claim if
such settlement is effected without the prior written consent of the Company,
which consent shall not be unreasonably withheld. Such indemnity shall remain in
full force and effect regardless of any investigation made by or on behalf of
the Indemnified Person and shall survive the transfer of the Registrable
Securities by the Investors pursuant to Section 9.

            b. In connection with any Registration Statement in which an
Investor is participating, each such Investor agrees to jointly and severally
indemnify, hold harmless and defend, to the same extent and in the same manner
as is set forth in Section 6(a), the Company, each of its directors, each of its
officers who signs the Registration Statement, each Person, if any, who controls
the Company within the meaning of the 1933 Act or the 1934 Act (such


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Person together with any other Indemnified Person, collectively an "INDEMNIFIED
PARTY"), against any Claim or Indemnified Damages to which any of them may
become subject, under the 1933 Act, the 1934 Act or otherwise, insofar as such
Claim or Indemnified Damages arise out of or are based upon any Violation, in
each case to the extent, and only to the extent, that such Violation occurs in
reliance upon and in conformity with information furnished to the Company by
such Investor expressly for use in connection with such Registration Statement;
and, subject to Section 6(d), such Investor will reimburse any legal or other
expenses reasonably incurred by them in connection with investigating or
defending any such Claim; provided, however, that the indemnity agreement
contained in this Section 6(b) and the agreement with respect to contribution
contained in Section 7 shall not apply to amounts paid in settlement of any
Claim if such settlement is effected without the prior written consent of such
Investor, which consent shall not be unreasonably withheld; provided, further,
however, that the Investor shall be liable under this Section 6(b) for only that
amount of a Claim or Indemnified Damages as does not exceed the net proceeds to
such Investor as a result of the sale of Registrable Securities pursuant to such
Registration Statement. Such indemnity shall remain in full force and effect
regardless of any investigation made by or on behalf of such Indemnified Party
and shall survive the transfer of the Registrable Securities by the Investors
pursuant to Section 9. Notwithstanding anything to the contrary contained
herein, the indemnification agreement contained in this Section 6(b) with
respect to any preliminary prospectus shall not inure to the benefit of any
Indemnified Party if the untrue statement or omission of material fact contained
in the preliminary prospectus was corrected on a timely basis in the prospectus,
as then amended or supplemented.

            c. The Company shall be entitled to receive indemnities from
underwriters, selling brokers, dealer managers and similar securities industry
professionals participating in any distribution, to the same extent as provided
above, with respect to information such persons so furnished expressly for
inclusion in the Registration Statement.

            d. Promptly after receipt by an Indemnified Person or Indemnified
Party under this Section 6 of notice of the commencement of any action or
proceeding (including any governmental action or proceeding) involving a Claim,
such Indemnified Person or Indemnified Party shall, if a Claim in respect
thereof is to be made against any indemnifying party under this Section 6,
deliver to the indemnifying party a written notice of the commencement thereof,
and the indemnifying party shall have the right (at its expense) to participate
in, and, to the extent the indemnifying party so desires, jointly with any other
indemnifying party similarly noticed, to assume control of the defense thereof
with counsel mutually satisfactory to the indemnifying party and the Indemnified
Person or the Indemnified Party, as the case may be; provided, however, that
such indemnifying party shall diligently pursue such defense and that an
Indemnified Person or Indemnified Party shall have the right to retain its own
counsel with the fees and expenses to be paid by the indemnifying party, if, in
the reasonable opinion of counsel retained by the Indemnified Person or
Indemnified Party, as the case may be, the representation by such counsel of the
Indemnified Person or Indemnified Party and the indemnifying party would be
inappropriate due to actual or reasonably anticipated differing interests
between such Indemnified Person or Indemnified Party and any other party
represented by such counsel in such proceeding. The Company shall pay reasonable
fees for only one separate legal counsel for the Investors, and such legal
counsel shall be selected by the Investors holding a majority in interest of the
Registrable Securities included in the Registration Statement to which the Claim


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relates. The Indemnified Party or Indemnified Person shall cooperate fully with
the indemnifying party in connection with any negotiation or defense of any such
action or claim by the indemnifying party and shall furnish to the indemnifying
party all information reasonably available to the Indemnified Party or
Indemnified Person which relates to such action or claim. The indemnifying party
shall keep the Indemnified Party or Indemnified Person fully apprised at all
times as to the status of the defense or any settlement negotiations with
respect thereto. No indemnifying party shall be liable for any settlement of any
action, claim or proceeding effected without its written consent, provided,
however, that the indemnifying party shall not unreasonably withhold, delay or
condition its consent. No indemnifying party shall, without the consent of the
Indemnified Party or Indemnified Person, consent to entry of any judgment or
enter into any settlement or other compromise unless such judgment, settlement
or compromise includes as an unconditional term thereof the giving by the
claimant or plaintiff to such Indemnified Party or Indemnified Person of a
release from all liability in respect to such claim or litigation, does not
materially and adversely impair the ability of such Indemnified Party or
Indemnified Person to conduct its business, and does not contain any admission
of wrongdoing on the part of any such Indemnified Party or Indemnified Person.
Following indemnification as provided for hereunder, the indemnifying party
shall be subrogated to all rights of the Indemnified Party or Indemnified Person
with respect to all third parties, firms or corporations relating to the matter
for which indemnification has been made. The failure to deliver written notice
to the indemnifying party within a reasonable time of the commencement of any
such action shall not relieve such indemnifying party of any liability to the
Indemnified Person or Indemnified Party under this Section 6, except to the
extent that the indemnifying party is prejudiced in its ability to defend such
action.

            e. The indemnification required by this Section 6 shall be made by
periodic payments of the amount thereof during the course of the investigation
or defense, as and when bills are received or Indemnified Damages are incurred.

            f. The indemnity agreements contained herein shall be in addition to
(i) any cause of action or similar right of the Indemnified Party or Indemnified
Person against the indemnifying party or others, and (ii) any liabilities the
indemnifying party may be subject to pursuant to the law.

      7.    CONTRIBUTION.

            To the extent any indemnification by an indemnifying party is
prohibited or limited by law, the indemnifying party agrees to make the maximum
contribution with respect to any amounts for which it would otherwise be liable
under Section 6 to the fullest extent permitted by law; provided, however, that:
(i) no contribution shall be made under circumstances where the maker would not
have been liable for indemnification under the fault standards set forth in
Section 6; (ii) no seller of Registrable Securities guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the 1933 Act) shall be
entitled to contribution from any seller of Registrable Securities who was not
guilty of fraudulent misrepresentation; and (iii) contribution by any seller of
Registrable Securities shall be limited in amount to the net amount of proceeds
received by such seller from the sale of such Registrable Securities.


                                       10
<PAGE>
      8.    REPORTS UNDER THE 1934 ACT.

      With a view to making available to the Investors the benefits of Rule 144
promulgated under the 1933 Act or any other similar rule or regulation of the
SEC that may at any time permit the Investors to sell securities of the Company
to the public without registration ("RULE 144"), the Company agrees to:

            a. make and keep public information available, as those terms are
understood and defined in Rule 144;

            b. file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements and the filing of such reports
and other documents is required for the applicable provisions of Rule 144; and

            c. furnish to each Investor so long as such Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144, the
1933 Act and the 1934 Act, (ii) a copy of the most recent annual or quarterly
report of the Company and such other reports and documents so filed by the
Company, and (iii) such other information as may be reasonably requested to
permit the Investors to sell such securities pursuant to Rule 144 without
registration.

      9.    ASSIGNMENT OF REGISTRATION RIGHTS.

      The rights to have the Company register Registrable Securities pursuant to
this Agreement shall be assignable by the Holder to an Investor (a "Transferee")
who receives no fewer than 125,000 Shares of the Registrable Securities and if:
(i) the Holder agrees in writing with the Transferee to transfer or assign such
rights, and a copy of such agreement is promptly furnished to the Company after
such transfer or assignment; (ii) the Company is, promptly after such transfer
or assignment, furnished with written notice of (a) the name and address of such
Transferee, and (b) the securities with respect to which such registration
rights are being transferred or assigned and the amount being transferred or
assigned; (iii) immediately following such transfer or assignment the further
disposition of such securities by the Transferee is restricted under the 1933
Act and applicable state securities laws; (iv) at or before the time the Company
receives the written notice contemplated by clause (ii) of this sentence the
Transferee agrees in writing with the Company to be bound by all of the
provisions contained herein; (v) such Transferee shall be an "accredited
investor" as that term is defined in Rule 501 of Regulation D promulgated under
the 1933 Act; and (vi) in the event the assignment occurs subsequent to the date
of effectiveness of the Registration Statement required to be filed pursuant to
Section 2(a), the Transferee agrees to pay all reasonable expenses of amending
or supplementing such Registration Statement to reflect such assignment.

      10.   AMENDMENT OF REGISTRATION RIGHTS.

      Provisions of this Agreement may be amended and the observance thereof may
be waived (either generally or in a particular instance and either retroactively
or prospectively), only with the written consent of the Company and Investors
who hold fifty-one percent (51%) of the


                                       11
<PAGE>
Registrable Securities. Any amendment or waiver effected in accordance with this
Section 10 shall be binding upon each Investor and the Company.

      11.   MISCELLANEOUS.

            a. A person or entity is deemed to be a holder of Registrable
Securities whenever such person or entity owns of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more persons or entities with respect to the same
Registrable Securities, the Company shall act upon the basis of instructions,
notice or election received from the registered owner of such Registrable
Securities.

            b. Any notices consents, waivers or other communications required or
permitted to be given under the terms of this Agreement must be in writing and
will be deemed to have been delivered: (i) upon receipt, when delivered
personally; (ii) upon receipt, when sent by facsimile, provided a copy is mailed
by U.S. certified mail, return receipt requested; (iii) three (3) days after
being sent by U.S. certified mail, return receipt requested; or (iv) one (1) day
after deposit with a nationally recognized overnight delivery service, in each
case properly addressed to the party to receive the same. The addresses and
facsimile numbers for such communications shall be:

            if to the Company:

                    Metrocall Holdings, Inc.
                    6677 Richmond Highway
                    Alexandria, Virginia 22306
                    Telephone:  (703) 660-6677
                    Facsimile:  (703) 768-9625
                    Attention:  President

            with a copy to:

                    Schulte Roth & Zabel LLP
                    919 Third Avenue
                    New York, New York 10022
                    Telephone:  (212) 756-2431
                    Facsimile:  (212)-593-5955



                                       12
<PAGE>
            Attention:  Andre Weiss, Esq.

            if to the Holder:

                    WebLink Wireless I, LP
                    3333 Lee Parkway, Suite 100
                    Dallas, Texas 75219
                    Telephone:  (214) 765-4000
                    Facsimile:  (214) 765-4902
                    Attention:  President

            with a copy to:

                    Weil, Gotshal & Manges LLP
                    767 Fifth Avenue
                    New York, New York 10153
                    Telephone:  (212) 310-8000
                    Facsimile:  (212)-310-8007
                    Attention:  Andrea A. Bernstein, Esq.

      Each party shall provide five (5) days prior notice to the other party of
any change in address, phone number or facsimile number.

            c. Failure of any party to exercise any right or remedy under this
Agreement or otherwise, or delay by a party in exercising such right or remedy,
shall not operate as a waiver thereof.

            d. This Agreement shall be governed by and interpreted in accordance
with the laws of the State of New York. If any provision of this Agreement shall
be invalid or unenforceable in any jurisdiction, such invalidity or
unenforceability shall not affect the validity or enforceability of the
remainder of this Agreement in that jurisdiction or the validity or
enforceability of any provision of this Agreement in any other jurisdiction.

            e. This Agreement, the Warrants, the Management Agreement and the
Asset Purchase Agreement (including all schedules and exhibits thereto)
constitute the entire agreement among the parties hereto with respect to the
subject matter hereof and thereof. There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein and
therein. The aforementioned documents supersede all prior agreements and
understandings among the parties hereto with respect to the subject matter
hereof and thereof.

            f. Subject to the requirements of Section 9, this Agreement shall
inure to the benefit of and be binding upon the permitted successors and assigns
of each of the parties hereto.

            g. The headings in this Agreement are for convenience of reference
only and shall not limit or otherwise affect the meaning hereof.


                                       13
<PAGE>
            h. This Agreement may be executed in two or more identical
counterparts, each of which shall be deemed an original but all of which shall
constitute one and the same agreement. This Agreement, once executed by a party,
may be delivered to the other party hereto by facsimile transmission of a copy
of this Agreement bearing the signature of the party so delivering this
Agreement.

            i. Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK.]

                                       14
<PAGE>
      IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be duly executed as of day and year first above written.


COMPANY:

METROCALL HOLDINGS, INC.


By:  /s/ Vincent D. Kelly
     ---------------------------
     Name:  Vincent D. Kelly
            --------------------
     Title  President and CEO
            --------------------


WEBLINK WIRELESS I, L.P.

By: WEBLINK WIRELESS, INC., its general partner


By:  /s/ N. Ross Buckenham
     ---------------------------
     Name:  N. Ross Buckenham
            --------------------
     Title  President and CEO
            --------------------