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                                                                     EXHIBIT 4.4



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                                METROCALL, INC.
                                    COMPANY



                                      AND


                       IBJ SCHRODER BANK & TRUST COMPANY
                                    TRUSTEE


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                              SECOND SUPPLEMENTAL
                                   INDENTURE



                         DATED AS OF NOVEMBER 15, 1996


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                   11 7/8% SENIOR SUBORDINATED NOTES DUE 2005
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                         SECOND SUPPLEMENTAL INDENTURE


         This Second Supplemental Indenture ("Second Supplemental Indenture")
is dated and is effective as of  November 15, 1996, and is by and between
METROCALL, INC., a Delaware corporation (the "Company," which term includes any
successor company permitted under the Indenture as modified by the First
Supplemental Indenture dated November 14, 1996), and IBJ SCHRODER BANK & TRUST
COMPANY, a New York banking corporation, as trustee (the "Trustee").

                              W I T N E S S E T H:

         WHEREAS, A+ Network, Inc. (the "Predecessor"), formerly a Tennessee
corporation,  has heretofore entered into an Indenture dated as of October 24,
1995 (as modified by the First Supplemental Indenture dated November 14, 1996,
the "Indenture"), with the Trustee, pursuant to which  the Predecessor  issued
$125,000,000 aggregate principal amount of its 11 7/8% Senior Subordinated
Notes Due 2005 (the "Securities");

         WHEREAS, the Predecessor, pursuant to an Agreement and Plan of Merger
dated as of May 16, 1996, as amended (the "Merger Agreement"), has merged with
and into the Company;

         WHEREAS, in accordance with the Merger Agreement, the Company has
succeeded to all right, title and interest of certain property of the
Predecessor and assumed the Predecessor's debts, liabilities, duties and
obligations, including the Predecessor's obligations under the Indenture;

         WHEREAS, under Section 801 of the Indenture, the Predecessor shall not
merge into any other corporation unless (among other things) the corporation
into which the Predecessor is merged shall be a corporation validly existing
under the laws of the United States of America, any state thereof or the
District of Columbia, and shall expressly assume, by a supplemental indenture
executed and delivered to the Trustee, in form satisfactory to the Trustee, the
Predecessor's obligation for the due and punctual payment of the principal
(premium, if any, on) and interest on all the Securities and the performance
and observance of every covenant of the Indenture on the part of the
Predecessor to be performed or observed;

         WHEREAS, the Company and the Trustee are authorized pursuant to
Section 901 of the Indenture to execute this Second Supplemental Indenture
without the consent of the Holders of the Securities in order to evidence the
merger of the Predecessor with and into the Company and the assumption by the
Company of the covenants of the Predecessor in the Indenture and in the
Securities;

         WHEREAS, all the requirements of law and the by-laws and Certificate
of Incorporation of the Company have been fully complied with and all other
acts and things necessary to make this Second Supplemental Indenture a valid,
binding and legal instrument for the uses and purposes





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herein set forth have been done and performed, including the authorization of
the execution and delivery of the Second Supplemental Indenture by the Board of
Directors of the Company;

         NOW, THEREFORE, in consideration of the premises herein contained, and
for other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the Company and the Trustee have joined in the
execution and delivery of this Second Supplemental Indenture.

                                  ARTICLE ONE
                    INCORPORATION OF INDENTURE; DEFINITIONS

     1.1         Incorporation of Indenture.  This Second Supplemental
Indenture constitutes a supplement  to the Indenture, and the Indenture and
this Second Supplemental Indenture shall be read together and shall have effect
so far as practicable as though all of the provisions thereof and hereof  are
contained in one instrument.

     1.2         Definitions.

     (a)         The defined term "Company" as used in the Indenture shall mean
Metrocall, Inc. instead of "A+ Network, Inc."

     (b)         All capitalized terms used herein and not otherwise defined
herein shall have the respective meanings assigned to such terms in the
Indenture.

                                  ARTICLE TWO
                    ASSUMPTION OF COVENANTS; EFFECTIVE TIME

     2.1         Assumptions of Obligations.  The Company expressly and
unconditionally assumes the due and punctual payment of the principal of (and
premium, if any) and interest on all the Securities and the performance and
observance of every covenant of the Indenture on the part of the Predecessor to
be performed or observed.  The Company shall succeed to, and be substituted
for, and may exercise every right and power of, the Predecessor under the
Indenture with the same effect as if the Company had been named therein, and
the Predecessor is hereby relieved of all such obligations.

     2.2         Effective Time.  This Second Supplemental Indenture is
executed by the Company and the Trustee pursuant to the provisions of Section
901 of the Indenture and shall take effect immediately upon its execution by
the Company and the Trustee and its delivery to the Trustee by the Company.



                                 ARTICLE THREE
                                 MISCELLANEOUS





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     4.1         Full Force and Effect.  The Indenture, as supplemented by this
Second Supplemental Indenture, remains in full force and effect and is hereby
ratified and confirmed as the valid and binding obligation of the parties
hereto.  Except as expressly modified herein, all terms, provisions and
conditions of the Indenture will remain unchanged and are and shall remain in
full force and effect for the full term thereof, and this Second  Supplemental
Indenture shall be interpreted with the Indenture as one and the same
instrument.

     4.2         Multiple Counterparts.  This Second Supplemental Indenture may
be executed in multiple counterparts, each of which shall be deemed an
original, but all of which taken together shall constitute one and the same
instrument.

     4.3         Headings for Convenience Only.  The headings of the Sections
of this Second Supplemental Indenture are used for convenience of  reference
only and shall not be deemed to affect the meaning or construction of any of
the provisions hereof.

     4.4         Governing Law.  This Second Supplemental Indenture shall be
governed by, and construed in accordance with, the laws of the State of New
York.

     4.5         Successors and Assigns.  All covenants and agreements in this
Second Supplemental Indenture by the Company shall bind its successors and
assigns, whether so expressed or not.

     4.6         Trustee Not Responsible for Recitals, etc.  The recitals
contained herein shall be taken as the statements of the Company, and the
Trustee assumes no responsibility whatsoever for their correctness nor for the
validity or sufficiency of this Second Supplemental Indenture or for the due
execution hereof by the Company.

     4.7         Certain Duties and Responsibilities of the Trustee.  In
entering into this  Second Supplemental Indenture, the Trustee accepts the
modifications of the Indenture effected by this Second Supplemental Indenture
and agrees to execute the trusts created by the Indenture as hereby modified,
but only upon the terms and conditions set forth in the Indenture. The Trustee
shall be entitled to the benefit of every provision of the Indenture relating
to the conduct or affecting the liability of or affording protection to the
Trustee, whether or not elsewhere herein so provided.

                         (SIGNATURES ON FOLLOWING PAGE)





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     IN WITNESS WHEREOF, the parties hereto have caused this Second
Supplemental Indenture to be executed and delivered effective as of the date
first mentioned hereinabove.


                                           METROCALL, INC.


                                           By:
                                                ----------------------------
                                           Name:
                                                  --------------------------
                                           Title:
                                                   -------------------------


                                           IBJ SCHRODER BANK & TRUST COMPANY,
                                           as Trustee


                                           By:
                                                ----------------------------
                                                   Name:
                                                   Title:






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