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                                                                     EXHIBIT 4.5



               AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

     This Amended and Restated Registration Rights Agreement dated as of March
31, 2000, is among Gabriel Communications, Inc., a Delaware corporation (the
"Company"), and all other parties that are signatory hereto or that have
executed an Instrument of Accession in the form of Exhibit A hereto.

                              W I T N E S S E T H:

     WHEREAS, pursuant to an Amended and Restated Stockholders' Agreement of
even date herewith among the parties hereto (as amended and in effect from time
to time, the "Stockholders' Agreement") and a Securities Purchase Agreement of
even date herewith among the Company and the Purchasers named therein providing
for the purchase and sale of Series B Convertible Preferred Stock of the Company
(as amended and in effect from time to time, the "Series B Purchase Agreement"),
the parties hereto have agreed to provide for the registration rights set forth
in this Agreement; and

     WHEREAS, certain parties to the Securities Purchase Agreement dated as of
November 18, 1998, as amended as of December 14, 1998, providing for the
purchase of shares of Series A Preferred Stock (as hereinafter defined) of the
Company, and certain other stockholders of the Company who are not also parties
to the Series B Purchase Agreement desire to amend and restate the Registration
Rights Agreement dated as of November 18, 1998;

     NOW, THEREFORE, the parties to this Agreement hereby agree as follows:

     1. Definitions. For all purposes of this Agreement, the following terms
shall have the meanings set forth below (capitalized terms used herein and not
otherwise defined herein shall have the meaning set forth in the Stockholders'
Agreement for such term):

     Commission means the Securities and Exchange Commission.

     Common Stock means (a) the Common Stock, $.01 par value per share, of the
Company and (b) any shares of any other class of capital stock of the Company
hereafter issued which is (i) not preferred in the Company's charter as to
dividends or assets over any class of stock of the Company, (ii) not subject to
redemption in the Company's charter, or (iii) issued to the holders of shares of
Common Stock upon any reclassification thereof.

     Demand Registration means any registration requested by the Stockholders
pursuant to Section 2(a)(i).

     indemnified party. As defined in Section 8(c).

     Instrument of Accession means an Instrument of Accession in the form of
Exhibit A hereto.




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     Person means an individual, partnership, corporation, association, trust,
joint venture, unincorporated organization, or any government, governmental
department or agency or political subdivision thereof.

     Piggyback Registration. As defined in Section 3(a)(i).

     Preferred Stock means (a) the Series A Preferred Stock, the Series A-1
Preferred Stock and the Series B Preferred Stock and (b) any shares of any other
class or series of preferred stock of the Company hereafter issued, including
any shares which are issued to the holders of shares of Preferred Stock upon any
reclassification thereof.

     Public Sale means any sale of Restricted Securities to the public pursuant
to a public offering registered under the Securities Act or to the public
through a broker or market-maker pursuant to the provisions of Rule 144 (or any
successor rule) adopted under the Securities Act or any other public offering
not required to be registered under the Securities Act.

     Registration Expenses. As defined in Section 7(a).

     registered and registration refer to a registration effected by preparing
and filing a registration statement in compliance with the Securities Act and
the declaration or ordering by the Commission of the effectiveness of such
registration statement.

     Restricted Securities means at any particular time all of the Company's
then outstanding shares of Stock, and all shares of Stock issuable upon exercise
of outstanding options or warrants or conversion of outstanding securities
convertible therefor, which have not been sold in a Public Sale, or which are
not able to be sold within any ninety (90) day period in a Public Sale pursuant
to the provisions of Rule 144 of the Securities Act.

     Securities Act means the Securities Act of 1933, as amended, or any
successor federal statute, and the rules and regulations of the Securities and
Exchange Commission thereunder, all as the same shall be in effect at the time.

     Series A Preferred Stock means the Series A Convertible Preferred Stock,
$.01 par value per share, of the Company.

     Series A-1 Preferred Stock means the Series A-1 Convertible Preferred
Stock, $.01 par value per share, of the Company

     Series B Preferred Stock means the Series B Convertible Preferred Stock,
$.01 par value per share, of the Company

     Stock means all shares of Common Stock or Preferred Stock now or hereafter
owned by the Stockholders.

     Stockholders means, initially, the Purchasers and the Management
Stockholders identified as such on the signature pages of this Agreement, and
thereafter any Person who becomes a party to this Agreement by executing an
Instrument of Accession in connection with the transfer to or





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acquisition by such Person of any Stock from any Purchaser or the Company or any
subsequent transferee of a Purchaser; provided that a Person shall cease to be a
Stockholder hereunder at such time as such Person ceases to own Restricted
Securities.

     Underwriters Maximum Number means for any Piggyback Registration, Demand
Registration or other registration which is an underwritten registration, that
number of securities to which such registration should, in the opinion of the
managing underwriters of such registration in the light of marketing factors, be
limited.

     2. Stockholder Demand Registration.

          (a) Request for Demand Registration.


          (i) Subject to the limitations contained in the following paragraphs
     of this Section 2, the holders of at least 20% of the total number of
     outstanding Restricted Securities may at any time after the earlier to
     occur of (A) November 18, 2002 and (B) the Company's initial public
     offering of the Common Stock, give to the Company, pursuant to this clause
     (i), a written request for a Demand Registration of Restricted Securities
     on SEC Form S-1 or any successor form (a "Long-Form Registration"). In the
     event of any such request for a Demand Registration of Restricted
     Securities prior to the Company's initial public offering of the Common
     Stock, the proposed public offering price (prior to underwriters' discounts
     and expenses) shall be equal to or exceed $15.00 per share of Common Stock
     (as adjusted for any stock dividends, combinations or splits with respect
     to the Common Stock) and the proposed aggregate proceeds to the
     Stockholders requesting the Demand Registration and the Company (prior to
     underwriters' discounts and expenses) shall be at least $30,000,000. In
     addition, at such time as the Company is eligible to utilize SEC Form S-3
     or any successor form thereto, the holders of at least 10% of the total
     number of outstanding Restricted Securities may give to the Company
     pursuant to this clause (i) a written request for a demand registration of
     Restricted Securities with an anticipated aggregate public offering price
     of not less than $5,000,000 on SEC Form S-3 or any successor form thereto
     (a "Short-Form Registration"). Within 10 days after the receipt by the
     Company of any such written request, the Company will give written notice
     of such registration request to all Stockholders.

          (ii) Subject to the limitations contained in the following paragraphs
     of this Section 2, after the receipt of such written request for a Demand
     Registration, (A) the Company will be obligated and required to include in
     such Demand Registration all Restricted Securities with respect to which
     the Company shall receive from Stockholders, within 30 days after the date
     on which the Company shall have given to all Stockholders a written notice
     of registration request pursuant to Section 2(a)(i) hereof, the written
     requests of such Stockholders for inclusion of their respective shares of
     Restricted Securities in such Demand Registration, and (B) the Company will
     use its reasonable best efforts in good faith to effect promptly the
     registration of all such Restricted Securities; provided, that, the Company
     shall not be obligated and required to cause the effectiveness of a Demand
     Registration of any convertible Restricted Securities unless and until such
     convertible Restricted Securities included in a Demand Registration shall
     have been





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     converted into Common Stock of the Company prior to or simultaneously with
     the effectiveness of a Demand Registration; and provided, further, that
     each Stockholder shall be entitled to convert any Common Stock so converted
     back into convertible Restricted Securities in the event such Demand
     Registration is not declared effective. All written requests made by
     Stockholders pursuant to this clause (ii) will specify the number of shares
     of Restricted Securities to be registered and will also specify the
     intended method of disposition thereof. Such method of disposition shall,
     in any case, be an underwritten offering if an underwritten offering is
     requested by holders of 51% or more of the Restricted Securities to be
     included in such Demand Registration.

          (iii) The Stockholders shall be permitted to withdraw all or any part
     of the Restricted Securities of such Stockholders from any Demand
     Registration at any time prior to the effective date of such Demand
     Registration but only in the case of an underwritten public offering, if
     such Stockholders are permitted to do so by the managing underwriters or
     pursuant to any agreement therewith. Upon such withdrawal, subject to
     Section 2(b)(ii), such Demand Registration shall count as a Demand
     Registration for purposes of Section 7(a) hereof unless the withdrawing
     Stockholder bears one-half of its pro rata share of the costs associated
     with such Demand Registration.

     (b) Limitations on Demand Registration.

          (i) The Stockholders will not be entitled to require the Company to
     effect any Demand Registrations pursuant to Section 2(a) hereof more
     frequently than once during any twelve-month period or within six months
     after the effective date of any Demand or Piggyback Registration pursuant
     to Sections 2 or 3 hereof. Registrations pursuant to this Section 2 shall
     be on Form S-1 or S-2 or, if any Demand Registration would be eligible for
     registration on Form S-3, the Company may effect such Demand Registration
     pursuant to Form S-3.

          (ii) Any registration initiated pursuant to Section 2(a) hereof shall
     not count as a Demand Registration for purposes of Section 7(a) hereof
     unless and until such registration shall have become effective and
     seventy-five percent (75%) of the number of shares initially included in
     the first filing with the Commission on Form S-1, S-2 or S-3, but not
     withdrawn under Section 2(a)(iii) above, shall have been actually sold.

          (iii) The Company shall not be obligated or required to effect the
     Demand Registration of any Restricted Securities pursuant to Section 2(a)
     hereof during the period commencing on the date falling 60 days prior to
     the Company's estimated date of filing of, and ending on the date 180 days
     following the effective date of, any registration statement pertaining to
     any underwritten registration initiated by the Company, for the account of
     the Company, if the written request of Stockholders for such Demand
     Registration pursuant to Section 2(a)(i) hereof shall have been received by
     the Company after the Company shall have given to all Stockholders a
     written notice stating that the Company is commencing an underwritten
     registration initiated by the Company; provided, however, that the Company
     will use its reasonable best efforts in good faith to cause any such
     registration statement to be filed and to become effective as expeditiously
     as shall be




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     reasonably possible. The Company shall not be required to maintain the
     effectiveness of any Demand Registration beyond the earlier to occur of (i)
     the consummation of the distribution by Stockholders of the Restricted
     Securities included therein or (ii) 120 days after the effective date
     thereof.

     (c) Priority on Demand Registrations. If the managing underwriters in any
Demand Registration pursuant to this Section 2 shall give written advice to the
Company and the Stockholders that, in their opinion, there is an Underwriters'
Maximum Number of shares of Restricted Securities that may successfully be
included in such registration, then: (i) if the Underwriters' Maximum Number is
less than the number of shares of Restricted Securities requested to be included
in such registration, the Company will be obligated and required to include in
such registration that number of shares of Restricted Securities which does not
exceed the Underwriters' Maximum Number, and such number of shares of Stock
shall be allocated pro rata among such Stockholders on the basis of the number
of shares of Restricted Securities requested to be included therein by each such
Stockholder; and (ii) if the Underwriters' Maximum Number exceeds the number of
shares of Restricted Securities requested to be included in such registration,
then the Company will be entitled to include in such registration that number of
securities which shall have been requested by the Company to be included in such
registration for the account of the Company and which shall not be greater than
such excess. Neither the Company nor any of its security holders (other than the
Stockholders) shall be entitled to include any securities in any underwritten
Demand Registration unless (i) the holders of sixty-six and two thirds percent
(66 2/3%) of the Restricted Securities to be included in such Demand
Registration by the Stockholders consent in writing to such inclusion and (ii)
the Company or such security holders (as the case may be) shall have agreed in
writing to sell such securities on the same terms and conditions as shall apply
to the Restricted Securities to be included in such Demand Registration.

     (d) Selection of Underwriters. If any Demand Registration or any
registration effected pursuant to Section 2 hereof is an underwritten offering,
or a best efforts underwritten offering, the investment bankers and managing
underwriters in such registration will be selected by the Company, subject to
the approval of the holders of 51% or more of the Restricted Securities to be
included in such registration.

     3. Piggyback Registrations.

          (a) Rights to Piggyback.

          (i) If (and on each occasion that) the Company proposes to register
     any of its equity securities or any other securities convertible into
     equity securities under the Securities Act for its own account or for the
     account of any holder of Restricted Securities (each such registration not
     withdrawn or abandoned prior to the effective date thereof being herein
     called a "Piggyback Registration"), the Company will give written notice to
     all Stockholders of such proposal not later than 20 days prior to the
     anticipated filing date of such Piggyback Registration.



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          (ii) Subject to the provisions contained in paragraphs (b) and (c) of
     this Section 3 and in the last sentence of this clause (ii), (A) the
     Company will be obligated and required to include in each Piggyback
     Registration all Restricted Securities with respect to which the Company
     shall receive from Stockholders, within 15 days after the date on which the
     Company shall have given written notice of such Piggyback Registration to
     all Stockholders pursuant to Section 3(a)(i) hereof, the written requests
     of such Stockholders for inclusion in such Piggyback Registration, and (B)
     the Company will use its reasonable best efforts in good faith to effect
     promptly the registration of all such Restricted Securities; provided, that
     the Company shall not be obligated and required to cause the effectiveness
     of a Piggyback Registration of any convertible Restricted Securities unless
     and until such convertible Restricted Securities included in a Piggyback
     Registration shall have been converted into Common Stock of the Company
     prior to or simultaneously with the effectiveness of a Piggyback
     Registration; and provided, further, that each Stockholder shall be
     entitled to convert any Common Stock so converted back into convertible
     Restricted Securities in the event such Demand Registration is not declared
     effective. The Stockholders shall be permitted to withdraw all or any part
     of the Restricted Securities of such Stockholders from any Piggyback
     Registration at any time prior to the effective date of such Piggyback
     Registration but only in the case of an underwritten offering if such
     Stockholders are permitted to do so by the managing underwriters or
     pursuant to any agreement therewith. The Company will not be obligated or
     required to include any Restricted Securities in any registration effected
     solely to implement an employee benefit plan or a transaction to which Rule
     145 of the Commission is applicable. The Company shall not be required to
     maintain the effectiveness of any Piggyback Registration beyond the earlier
     to occur of (i) the consummation of the distribution by holders of
     Restricted Securities included in such Piggyback Registration or (ii) 120
     days after the effective date thereof.

          (b) Priority on Primary Registrations. If a Piggyback Registration is
an underwritten primary registration initiated by the Company for its own
account, and the managing underwriters shall give written advice to the Company
that, in their opinion, there is an Underwriters' Maximum Number of securities
that may successfully be included in such registration, then: (i) the Company
shall be entitled to include in such registration that number of securities
which the Company proposes to offer and sell for its own account in such
registration and which does not exceed the Underwriters' Maximum Number; and
(ii) the Company will be obligated and required to include in such registration
that number of shares of Restricted Securities which shall have been requested
by the holders thereof to be included in such registration and which does not
exceed the difference between the Underwriters' Maximum Number and that number
of securities which the Company is entitled to include therein pursuant to
clause (i) above and such number of shares of Restricted Securities shall be
allocated pro rata among such Stockholders on the basis of the number of shares
of Restricted Securities requested to be included therein by each such
Stockholder.

          (c) In no event will shares of any holder of Restricted Stock (other
than the Stockholders) be included in any such Piggyback Registration if such
inclusion would reduce the number of shares which may be included by the
Stockholders without the written consent of




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Stockholders holding no less than sixty-six and two-thirds percent (66 2/3%) of
the Restricted Securities proposed to be included in such Piggyback
Registration.

          (d) Selection of Underwriters. In any Piggyback Registration, the
Company shall (unless the Company shall otherwise agree) have the right to
select the investment bankers and managing underwriters in such registration.

     4.   Lockup Agreements.

          (a) Restrictions on Public Sale by Stockholders. Each Stockholder, if
the Company or the managing underwriters so requests in connection with such
registration, will not, without the prior written consent of the Company or such
underwriters, effect any Public Sale or other distribution of any equity
securities of the Company, including any sale pursuant to Rule 144, during the
seven days prior to, and during the ninety-day period (180 day period in the
case of the Company's initial public offering of the Common Stock) commencing on
the effective date of such underwritten registration, except in connection with
such underwritten registration.

          (b) Restrictions on Public Sale by the Company. The Company agrees,
unless it obtains the consent of the managing underwriter(s) of any underwritten
offering of Restricted Securities pursuant to Sections 2 or 3 hereof, not to
effect any public sale or distribution of its equity securities, or any
securities convertible into or exchangeable or exercisable for such equity
securities, during the period commencing on the seventh day prior to, and ending
on the ninetieth day (in the case of the Company's initial public offering of
the Common Stock 180 day period) following, the effective date of any
underwritten Demand or Piggyback Registration, except in connection with any
such underwritten registration, pursuant to any employee benefit plan or, if the
managing underwriter(s) agrees, as part of an acquisition.

     5.   Registration Procedures. If (and on each occasion that) the Company
shall become obligated to effect any registration of any Restricted Securities
hereunder, the Company will use its reasonable best efforts in good faith to
effect promptly the registration of such Restricted Securities under the
Securities Act and to permit the public offering and sale of such Restricted
Securities in accordance with the intended method of disposition thereof, and,
in connection therewith, the Company, as expeditiously as shall be reasonably
possible, will:

          (a) prepare and file with the Commission a registration statement with
respect to such Restricted Securities, and use its reasonable best efforts in
good faith to cause such registration statement to become and remain effective
as provided herein;

          (b) prepare and file with the Commission such amendments and
supplements to such registration statement and the prospectus included in such
registration statement as may be necessary or advisable to comply in all
material respects with the provisions of the Securities Act with respect to the
disposition of all securities covered by such registration statement or as may
be necessary to keep such registration statement effective and current as
provided herein;

          (c) furnish to each seller of Restricted Securities such number of
copies of such registration statement, each amendment and supplement thereto (in
each case including all





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exhibits thereto), the prospectus included in such registration statement
(including each preliminary prospectus), and such other documents as any such
seller may reasonably request in order to facilitate the disposition of the
Restricted Securities held by such seller;

          (d) enter into such customary agreements (provided they do not require
the issuance of securities at a discount to any underwriter) and take all such
other customary actions in connection therewith as the Stockholders holding 51%
or more of the Restricted Securities being registered reasonably request in
order to expedite or facilitate the disposition of such Restricted Securities;

          (e) use its reasonable best efforts in good faith to register and
qualify the Restricted Securities covered by such registration statement under
such securities or blue sky laws of such jurisdictions as any seller (or the
managing underwriter, in the case of any underwritten offering) shall reasonably
request and do any and all such other acts and things as may be reasonably
necessary or advisable to permit the disposition in such jurisdictions of the
Restricted Securities covered by such registration statement; provided, however
that the Company shall not be required in connection therewith to qualify to do
business or file a general consent to service of process in any such
jurisdiction or subject itself to taxation in any jurisdiction where the Company
is not already subject to taxation; and

          (f) furnish to each prospective seller a signed counterpart, addressed
to the prospective sellers, (or to the underwriters, in the case of any
underwritten offering) of (i) an opinion of counsel for the Company, dated the
effective date of the registration statement, and (ii) a "comfort" letter signed
by the independent public accountants who have certified the Company's financial
statements included in the registration statement, covering substantially the
same matters with respect to the registration statement (and the prospectus
included therein) and (in the case of the "comfort" letter) with respect to
events subsequent to the date of the financial statements, as are customarily
covered (at the time of such registration) in opinions of issuer's counsel and
in "comfort" letters delivered to the underwriters in underwritten public
offerings of securities.

     6.   Cooperation by Prospective Sellers, Etc.

          (a) Each prospective seller of Restricted Securities will furnish to
the Company in writing such information as the Company may reasonably require
and which is customary in such transactions from such seller (as to such seller,
the Restricted Securities held by such seller and the intended method of
distribution of such Restricted Securities), and otherwise reasonably cooperate
with the Company in connection with any registration statement with respect to
such Restricted Securities, and the Company may exclude from such Registration
Statement the Restricted Securities of any prospective seller who fails to
furnish such reasonably requested information within 30 days after receiving
such request.

          (b) The failure of any prospective seller of Restricted Securities to
furnish any information or documents in accordance with any provision contained
in this Agreement shall not affect the obligations of the Company under this
Agreement to any remaining sellers who furnish such information and documents
unless in the reasonable opinion of counsel to the Company or





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the underwriters, such failure impairs or may impair the viability of the
offering or the legality of the registration statement or the underlying
offering.

          (c) The Stockholders included in any registration statement will not
(until further notice) effect sales of Restricted Securities included in any
registration statement after receipt of telegraphic or written notice from the
Company to suspend sales to permit the Company to correct or update such
registration statement or prospectus; but the obligations of the Company with
respect to maintaining any registration statement current and effective shall be
extended by a period of days equal to the period such suspension is in effect.

          (d) At the end of any period during which the Company is obligated to
keep any registration statement current and effective as provided herein (and
any extensions thereof required by the preceding paragraph (c) of this Section
6), the Stockholders included in such registration statement shall discontinue
sales of shares pursuant to such registration statement upon receipt of notice
from the Company of its intention to remove from registration the shares covered
by such registration statement which remain unsold, and such Stockholders shall
notify the Company of the number of shares registered which remain unsold
promptly after receipt of such notice from the Company.

     7.   Registration Expenses.

          (a) Except as otherwise provided herein, all out of pocket costs and
expenses incurred or sustained by the Company in connection with or arising out
of the first two Long-Form Demand Registrations and two Short-Form Demand
Registrations pursuant to Section 2 hereof and each registration pursuant to
Section 3 hereof, including, without limitation, all registration and filing
fees, fees and expenses of compliance with federal and state securities or blue
sky laws (including reasonable fees and disbursements of counsel for the
underwriters in connection with the blue sky qualification of Restricted
Securities), printing expenses, messenger, telephone and delivery expenses, fees
and disbursements of counsel for the Company, reasonable fees and disbursements
of one counsel representing any or all of the holders of Stock, fees and
disbursements of all independent certified public accountants of the Company
(including the expenses relating to the preparation and delivery of any special
audit or "cold comfort" letters required by or incident to such registration),
and fees and disbursements of underwriters, including any qualified independent
underwriter (excluding discounts, commissions and expenses representing
disguised commissions), the reasonable fees and expenses of any special experts
retained by the Company of its own initiative or at the request of the managing
underwriters in connection with such registration, and fees and expenses of all
(if any) other persons retained by the Company (all such costs and expenses
being herein called, collectively, the "Registration Expenses"), will be borne
and paid by the Company; provided, however, that the Company shall not pay nor
otherwise be responsible for any legal fees or disbursements of additional
counsel other than as set forth above. The Company will, in any case, pay its
internal expenses (including, without limitation, all salaries and expenses of
its officers and employees performing legal or accounting duties), the expense
of any annual audit, and the fees and expenses incurred in connection with the
listing of the securities to be registered on each securities exchange on which
similar securities of the Company are then listed.




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          (b) The Company will not bear the cost of nor pay for any stock
transfer taxes imposed in respect of the transfer of any Restricted Securities
to any purchaser thereof by any Stockholder in connection with any registration
of Restricted Securities pursuant to this Agreement.

          (c) To the extent that Registration Expenses incident to any
registration are, under the terms of this Agreement, not required to be paid by
the Company, each Stockholder included in such registration will pay all
Registration Expenses which are clearly solely attributable to the registration
of such Stockholder's Restricted Securities so included in such registration,
and all other Registration Expenses not so attributable to one Stockholder will
be borne and paid by all sellers of securities included in such registration in
proportion to the number of securities so included by each such seller.

     8. Indemnification.

          (a) Indemnification by the Company. To the full extent permitted by
law, the Company will indemnify each Stockholder requesting or joining in a
registration and each underwriter of the securities so registered, the officers,
directors, agents, employees, members, partners, trustees and fiduciaries of
each such Person and each Person, if any, who controls any thereof (within the
meaning of the Securities Act) against any and all claims, losses, damages and
liabilities (or actions in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) of any material fact contained in
any registration statement, prospectus or any amendment or supplement thereto,
or any document filed pursuant to state securities laws (or in any related
registration statement, notification or the like) or any omission (or alleged
omission) to state therein any material fact required to be stated therein or
necessary to make the statements therein not misleading, or any violation by the
Company of the Securities Act or any rule or regulation promulgated under the
Securities Act applicable to the Company and relating to any action or inaction
required of the Company in connection with any such registration, qualification
or compliance, and the Company will reimburse each such Stockholder,
underwriter, and each other Person indemnified pursuant to this paragraph (a)
for any legal and any other expenses reasonably incurred in connection with
investigating or defending any such claim, loss, damage, liability or action;
provided, however, that the Company will not be liable in any such case to the
extent that any such claim, loss, damage, liability or expense arises out of or
is based on any untrue statement or omission (or alleged untrue statement or
omission) made in reliance upon and in conformity with written information
furnished to the Company in an instrument duly executed by such Stockholder,
underwriter, officer, director, partner or controlling person and stated to be
specifically for use therein.

          (b) Indemnification by Each Stockholder. Each Stockholder requesting
or joining in a registration will severally and not jointly indemnify each
underwriter of the securities so registered, the Company, each of the other
Stockholders selling Restricted Securities in such registration and the
officers, directors, agents, employees, members, partners, trustees and
fiduciaries of each such Person and each Person, if any, who controls any
thereof (within the meaning of the Securities Act) and their respective
successors in title and assigns against any and all claims, losses, damages and
liabilities (or actions in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) of any material fact contained in
any






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registration statement, prospectus, or any amendment or supplement thereto, or
any document filed pursuant to state securities laws (or in any related
registration statement, notification or the like) or any omission (or alleged
omission) to state therein any material fact required to be stated therein or
necessary to make the statements therein not misleading, or any violation by
such Stockholder of any rule or regulation promulgated under the Securities Act
applicable to such Person and relating to any action or inaction required of
such Person in connection with any such registration, qualification or
compliance, and such Stockholder will reimburse each underwriter, the Company
and each other Person indemnified pursuant to this paragraph (b) for any legal
and any other expenses reasonably incurred in connection with investigating or
defending any such claim, loss, damage, liability or action; provided, however,
that this paragraph (b) shall apply only if (and only to the extent that) such
statement or omission (or alleged untrue statement or omission) was made in
reliance upon and in conformity with written information furnished to such
underwriter or the Company in an instrument duly executed by any such
Stockholder or any officer, director, partner or controlling person of such
Stockholder and stated to be specifically for use therein, and provided further
that each Stockholder's liability hereunder (including, without limitation,
Section 9) with respect to any particular registration shall be limited to an
amount equal to the net proceeds received by such Stockholder from the sale of
the Restricted Securities sold by such Stockholder in such registration. The
Company and the Stockholders shall be entitled to receive indemnities from
underwriters participating in any distribution of Restricted Securities to the
same extent as provided above with respect to information so furnished in
writing by such underwriters expressly for use in any prospectus or registration
statement.

          (c) Indemnification Proceedings. Each party entitled to
indemnification pursuant to this Section 8 (the "indemnified party") shall give
notice to the party required to provide indemnification pursuant to this Section
8 (the "indemnifying party") promptly after such indemnified party acquires
actual knowledge of any claim as to which indemnity may be sought, and shall
permit the indemnifying party (at its expense), upon written notice to the
indemnified party within thirty (30) days after receipt of the indemnified
party's notice, to assume the defense of any claim or any litigation resulting
therefrom; provided that counsel for the indemnifying party, who shall conduct
the defense of such claim or litigation, shall be reasonably acceptable to the
indemnified party (unless objected to within ten (10) days after the
indemnifying party's notice, such counsel shall be deemed acceptable), and the
indemnified party may participate in such defense at the indemnified party's
expense; and provided, further, that (i) the failure by any indemnified party to
give notice as provided in this paragraph (c) shall not relieve the indemnifying
party of its obligations under this Section 8 except to the extent that the
failure results in a failure of actual notice to the indemnifying party and such
indemnifying party is materially prejudiced solely as a result of the failure to
give notice and (ii) in the event of any failure of the indemnifying party to
retain counsel to assume the defense of such claim or litigation within thirty
(30) days after receipt of the indemnified party's notice, the indemnified party
may retain such counsel at the indemnifying party's expense. No indemnifying
party, in the defense of any such claim or litigation, shall, except with the
consent of each indemnified party, consent to entry of any judgment or enter
into any settlement which does not include as an unconditional term thereof the
giving by the claimant or plaintiff to such indemnified party of a release from
all liability in respect to such claim or litigation or which includes an
admission of fault by the





                                       11
<PAGE>   12
indemnified party or the entry of any injunction against the indemnified party.
The reimbursement required by this Section 8 shall be made by periodic payments
during the course of the investigation or defense, as and when bills are
received or expenses incurred.

          9. Contribution in Lieu of Indemnification. If the indemnification
provided for in Section 8 hereof is unavailable to a party that would have been
an indemnified party under any such section in respect of any losses, claims,
damages or liabilities (or actions in respect thereof) referred to therein, then
each party that would have been an indemnifying party thereunder shall, in lieu
of indemnifying such indemnified party, contribute to the amount paid or payable
by such indemnified party as a result of such losses, claims, damages or
liabilities (or actions in respect thereof) in such proportion as is appropriate
to reflect the relative fault of the indemnifying party on the one hand and such
indemnified party on the other in connection with the statements or omissions
which resulted in such losses, claims, damages or liabilities (or actions in
respect thereof); provided that each Stockholder's liability hereunder
(including, without limitation, Section 8) with respect to any particular
registration shall be limited to an amount equal to the net proceeds received by
such Stockholder from the sale of the Restricted Securities sold by such
Stockholder in such registration. The relative fault shall be determined by
reference to, among other things, whether the untrue or alleged untrue statement
of a material fact or the omission or alleged omission to state a material fact
relates to information supplied by the indemnifying party or such indemnified
party and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission. The Company and
each Stockholder agree that it would not be just and equitable if contribution
pursuant to this Section 9 were determined by pro rata allocation or by any
other method of allocation which does not take account the equitable
considerations referred to above in this Section 9. The amount paid or payable
by an indemnified party as a result of the losses, claims, damages or
liabilities (or actions in respect thereof) referred to above in this Section 9
shall include any legal or other expenses reasonably incurred by such
indemnified party in connection with investigating or defending any such action
or claim. No Person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to indemnification or
contribution from any Person who was not guilty of such fraudulent
misrepresentation.

          10. Rule 144 Requirements; Form S-3. From time to time after the
earlier to occur of (a) the ninetieth day following the date on which there
shall first become effective a registration statement filed by the Company under
the Securities Act with respect to its equity securities, or (b) the date on
which the Company shall register a class of equity securities under Section 12
of the Securities Exchange Act of 1934, the Company will use its reasonable best
efforts in good faith to take all steps necessary to ensure that the Company
will be eligible to register securities on Form S-3 (or any comparable form
adopted by the Commission) as soon thereafter as possible, and to file all
reports required to be filed by it under the Securities Exchange Act of 1934 in
order that there will be publicly available current public information
concerning the Company within the meaning of Rule 144(c) of the Commission under
the Securities Act. The Company will furnish to any Stockholder, upon request
made by such Stockholder at any time after the undertaking of the Company in the
preceding sentence shall have first become effective, a written statement signed
by the Company, addressed to such Stockholder, describing briefly the action the
Company has taken or proposes to take to comply with the current public
information requirements of Rule 144. The Company will, at the request of any
Stockholder, upon receipt from such Stockholder





                                       12
<PAGE>   13
of a certificate certifying (i) that such Stockholder has held such Restricted
Securities for a period of not less than two (2) consecutive years calculated as
described in paragraph (d) of Rule 144, (ii) that such Stockholder has not been
an affiliate (as defined in paragraph (a) of Rule 144) of the Company for more
than the preceding three months, and (iii) as to such other matters as may be
appropriate in accordance with such Rule, remove from the stock certificates
representing such Restricted Securities that portion of any restrictive legend
which relates to the registration provisions of the Securities Act, and,
thereupon, such Restricted Securities will cease to be Restricted Securities for
purposes of this Agreement.

          11. Participation in Underwritten Registrations. No person may
participate in any underwritten registration pursuant to this Agreement unless
such person (a) agrees to sell such person's securities on the basis provided in
any underwriting arrangements approved by the persons entitled, under the
provisions hereof, to approve such arrangements, and (b) completes and executes
all questionnaires, powers of attorney, indemnities, underwriting agreements and
other documents reasonably required by the terms of such underwriting
arrangements. Any Stockholder to be included in any underwritten registration
shall be entitled at any time to withdraw such Restricted Securities from such
registration prior to the execution of the related underwriting agreement in the
event that such Stockholder shall disapprove of any of the terms of such
agreement.

     12. Miscellaneous.

          (a) No Inconsistent Agreements. The Company hereby represents and
warrants that it is not a party to or bound in any manner under, and covenants
that it will not enter into at any time after the date hereof, any agreement or
contract (whether written or oral) with respect to any of its securities which
grants to any securityholder (other than under this Agreement) any demand
registration rights or prevents the Company from complying in any respect with
the registration rights granted by the Company to the Stockholders hereunder.

          (b) Amendments and Waivers. The provisions of this Agreement,
including the provisions of this paragraph (b), may not be amended, modified or
supplemented, and any waiver or consent to or any departure from any of the
provisions of this Agreement may not be given and shall not become or be
effective, unless and until (in each case) the Company shall have received the
prior written consent of the holders of at least 66 2/3% of the Restricted
Securities then outstanding to any such amendment, modification, supplement,
waiver or consent; provided however, that any amendment, modification or waiver
of any provision of this Agreement that affects only one or more particular
parties hereto to this Agreement may become effective only with the written
approval of such party or parties.

          (c) Restricted Securities Held by the Company. Whenever the consent or
approval of Stockholders is required pursuant to this Agreement, Restricted
Securities held by the Company shall not be counted in determining whether such
consent or approval was duly and properly given by such Stockholders.

          (d) Term. The agreements of the Company contained in this Agreement
shall continue in full force and effect so long as any Stockholder holds any
Restricted Securities.



                                       13
<PAGE>   14
          (e) Notices. Any notice or other communication in connection with this
Agreement shall be deemed to be delivered if in writing (or in the form of a
telex or telecopy) addressed as provided below (a) when actually delivered, in
person, (b) when telexed or telecopied to said address, confirmed by registered
or certified mail, (c) when received if delivered by overnight courier, or (d)
in the case of delivery by mail, three business days shall have elapsed after
the same shall have been deposited in the United States mails, postage prepaid
and registered or certified:

          (i) if to a Stockholder, at such Stockholder's address on the stock
     transfer books of the Company (which the Company shall make available for
     determining the address of any Stockholder for notification purposes
     hereunder).

          (ii) if to the Company, at:

               16650 Chesterfield Grove Rd.
               Suite 110
               Chesterfield, MO 63006
               Attention: Chairman or President

          with a copy to:

               Nick H. Varsam, Esq.
               Bryan Cave, LLP
               One Metropolitan Square
               211 N. Broadway
               St. Louis, MO 63102

and thereafter at such other address, notice of which is given in accordance
with the provisions of this Section 13(e).

          (f) Successors and Assigns. This Agreement shall inure to the benefit
of and be binding upon the successors and assigns of each of the parties,
including, without limitation, subsequent holders of Stock agreeing to be bound
by all of the terms and conditions of this Agreement by executing an Instrument
of Accession in the form set forth in attached Exhibit A.

          (g) Counterparts. This Agreement may be executed in one or more
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same instrument.

          (h) Headings. The headings in this Agreement are for convenience of
reference only and shall not constitute a part of this Agreement, nor shall they
affect the meaning, construction or effect of any of the terms of this
Agreement.

          (i) Governing Law. The validity, performance, construction and effect
of this Agreement shall be governed by and construed in accordance with the
internal laws of the State of New York, without giving effect to principles of
conflicts of law.




                                       14
<PAGE>   15
          (j) Severability. In the event that any one or more of the provisions
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable, the validity, legality and enforceability of
any such provision in every other respect and of the remaining provisions
contained herein shall not be affected or impaired thereby.

          (k) Entire Agreement. This Agreement is intended by the parties as a
final expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect of
the subject matter contained herein. There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein,
with respect to the registration rights granted by the Company with respect to
the Restricted Securities. This Agreement supersedes all prior agreements and
understandings between the parties with respect to such subject matter.




                                       15
<PAGE>   16
         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first written above.

                                     GABRIEL COMMUNICATIONS, INC.





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



                                       16
<PAGE>   17




PURCHASERS:

BROOKS INVESTMENTS, L.P.                 RAB PARTNERSHIP, L.P.

By:  Brooks Investments, Inc.            By:
Its: General Partner                        ------------------------------------
                                             Robert A. Brooks
                                             General Partner
By:
   ------------------------------------
    Robert A. Brooks,
    President


ONELIBERTY FUND IV, L.P.                 ONELIBERTY ADVISORS FUND IV, L.P.
By:  OneLiberty Partners IV, L.L.C.      By:  OneLiberty Partners IV, L.L.C.
Its: General Partner                     Its: General Partner

By:                                      By:
   ------------------------------------     ------------------------------------


GS CAPITAL PARTNERS III, L.P.            GS CAPITAL PARTNERS III OFFSHORE, L.P.
By:  GS Advisors III, L.P.               By:  GS Advisors III (Cayman), L.P.
Its: General Partner                     Its: General Partner
By:  GS Advisors III, L.L.C.             By:  GS Advisors III, L.L.C.
Its: General Partner                     Its: General Partner

By:                                      By:
   ------------------------------------     ------------------------------------


GOLDMAN, SACHS & CO.                     STONE STREET FUND 2000, L.P.
VERWALTUNGS GmbH                         By:  Stone Street 2000, L.L.C.
                                         Its: General Partner
By:
   ------------------------------------
    Managing Director                    By:
                                            ------------------------------------


By:
   ------------------------------------
    Registered Agent

STONE STREET FUND 1998, L.P.             BRIDGE STREET FUND 1998, L.P.
By:  Stone Street Advantage Corp.        By:  Stone Street Advantage Corp.
Its: General Partner                     Its: General Partner

By:                                      By:
   ------------------------------------     ------------------------------------



                                       17
<PAGE>   18

BRIDGE STREET SPECIAL OPPORTUNITIES
FUND 2000, L.P.
By:  Bridge Street Special Opportunities 2000, L.L.C.
Its: General Partner


By:
   ------------------------------------

J. H. WHITNEY III, L.P.                     WHITNEY STRATEGIC PARTNERS III, L.P.
By:                                         By:
Its: General Partner                        Its: General Partner

By:                                         By:
   ------------------------------------        ---------------------------------




J. H. WHITNEY IV, L.P.                      CENTENNIAL FUND V, L.P.
By:  J. H. Whitney Equity Partners IV, LLC  By:  Centennial Holdings V, L.P.
Its: General Partner                        Its: General Partner

By:                                         By:
   ------------------------------------        ---------------------------------
                                                  Steven C. Halstedt
                                                  A General Partner

CHASE VENTURE CAPITAL                       NORWEST EQUITY PARTNERS VI, L.P.
ASSOCIATES, L.P.                            By:
By:                                         Its: General Partner
Its: General Partner

By:                                         By:
   ------------------------------------        ---------------------------------



TELECOM PARTNERS II, L.P.                   DON INVESTMENT GROUP, L.P.
By:  Telecom Management II, L.L.C.,         By:  BGC Investors, Inc.
Its: General Partner                        Its: General Partner

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






                                       18
<PAGE>   19
CENTENNIAL ENTREPRENEURS                 MERITAGE ENTREPRENEURS FUND, L.P.
FUND V, L.P.                             By:  Meritage Investment Partners, LLC
By:  Centennial Holdings V, L.P.         Its: General Partner
Its: General Partner

By:                                      By:
   ------------------------------------     ------------------------------------
    Steven C. Halstedt
    A General Partner

MERITAGE PRIVATE EQUITY FUND, L.P.       MERITAGE PRIVATE EQUITY PARALLEL
                                         FUND, L.P.
By:  Meritage Investment Partners, LLC   By:  Meritage Investment Partners, LLC
Its: General Partner                     Its: General Partner

By:                                      By:
   ------------------------------------     ------------------------------------



                                       19
<PAGE>   20
MANAGEMENT STOCKHOLDERS:







------------------------------------     ------------------------------------
Ross Bopp                                Larry W. Britt

                                         Brian L. Butler and Susan L. Butler
                                         Joint Caring Trust dated July 7, 1988
------------------------------------
Robert A. Brooks                         By:
                                            ------------------------------------
                                               Trustee


------------------------------------     ------------------------------------
Edward Cadieux                           Barbara A. Clements


------------------------------------     ------------------------------------
John P. Denneen                          Gary W. Eaves

Thomas P. Erickson Revocable Trust       Marguerite A. Forrest Revocable Trust
U/T/A dated April 6, 1998                U/T/A dated August 11, 1998

By:                                      By:
   ------------------------------------     ------------------------------------
    Trustee                                    Trustee


------------------------------------     ------------------------------------
Jennifer Garner                          Gerard J. Howe


------------------------------------     ------------------------------------
Jeffrey M. Jay                           Dale Kammerich


------------------------------------     ------------------------------------
Kevin J. Keaveny                         Brett Kirby


------------------------------------     ------------------------------------
Ivan Kuhn                                Bobby Maddox



                                       20
<PAGE>   21
------------------------------------     ------------------------------------
Gregory P. Pace                          John Presley


------------------------------------     ------------------------------------
Richard Scott                            Richard G. Sikora

                                         Tettambel Investments LLC
------------------------------------
David L. Solomon                         By:
                                            ------------------------------------
                                         Name:
                                         Title:


------------------------------------     ------------------------------------
Christopher A. Thornton                  Gregory H. Truitt


                                         Tettambel Irrevocable Family Trust
------------------------------------     Dated March 7, 2000
Janet M. Wendel

Keaveny Family Millenium Trust
Dated March 10, 2000                     By:
                                            ------------------------------------
                                               Trustee
By:
   ------------------------------------
    Trustee
                                         Catherine B. Howe Irrevocable Trust
By:                                      U/T/A Dated November 17, 1998
   ------------------------------------
    Trustee
                                         By:
                                            ------------------------------------
Margaret A. Howe Irrevocable Trust U/T/A       Trustee
Dated November 17, 1998
                                         By:
                                            ------------------------------------
By:                                            Trustee
   ------------------------------------
    Trustee
                                         Thomas P. Erickson Individual
By:                                      Retirement Account
   ------------------------------------
    Trustee
                                         By:
                                            ------------------------------------
                                         Name:
                                         Title:









                                       21
<PAGE>   22
                                                                       EXHIBIT A



                             Instrument of Accession


     Reference is made to that certain Amended and Restated Registration Rights
Agreement dated as of March 31, 2000, a copy of which is attached hereto (as
amended and in effect from time to time, the "Registration Rights Agreement"),
among Gabriel Communications, Inc., a Delaware corporation (the "Company"), and
the Stockholders of the Company (as defined therein).

     The undersigned,               , in order to become the owner or holder of
         shares (the "Shares") of              Stock, hereby agrees that by the
undersigned's execution hereof (a) the undersigned is a Stockholder party to the
Registration Rights Agreement subject to all of the rights, restrictions and
conditions applicable to Stockholders set forth in the Registration Rights
Agreement, and (b) all of the Shares (and any and all shares of stock of the
Company issued in respect thereof) constitute Restricted Securities subject to
all the rights, restrictions and conditions applicable to Restricted Securities
as set forth in the Registration Rights Agreement. This Instrument of Accession
shall take effect and shall become a part of said Registration Rights Agreement
immediately upon execution.

     Executed as of the date set forth below under the laws of the State of
Delaware.


                                    Signature:
                                              ----------------------------------

                                    Address:
                                              ----------------------------------
                                              ----------------------------------
                                              ----------------------------------

                                    Date:
                                              ----------------------------------

Accepted:

GABRIEL COMMUNICATIONS, INC.


By:
   ----------------------------------

Date:
     --------------------------------