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                                                                     EXHIBIT 4.3


                          GABRIEL COMMUNICATIONS, INC.
                             SHAREHOLDERS AGREEMENT

          THIS AGREEMENT, made as of this 14th day of August, 1998, as amended
by Agreement dated as of November 18, 1998, and as amended by Agreement dated as
of December 13, 1999, by and between GABRIEL COMMUNICATIONS, INC., a Delaware
corporation, hereinafter referred to as the "Corporation," and the following
individuals, hereinafter sometimes referred to collectively as "Shareholders" or
individually as "Shareholder":

                              Robert A. Brooks
                              Brian Butler
                              Barbara Clements
                              Gary Eaves
                              Thomas Erickson
                              Marguerite Forest
                              Gerard Howe
                              Kevin Keaveny
                              Brett Kirby
                              Timothy Tettambel
                              Janet Wendel
                              Brooks Investments, L.P.
                              The Goldman Sachs Group, L.P.


          WITNESSETH:

          The Shareholders own shares of the Common Stock (hereinafter referred
to as "Shares") of the Corporation as indicated on Exhibit "A" to this
Agreement; and

          WHEREAS, the Corporation's business is such that it is in its best
interests that its Shares be owned by persons who are active in the business of
the Corporation, and the Corporation and Shareholders desire to provide for
continuity and harmony in the management of the Corporation;

          WHEREAS, in the event of the death, total permanent disability, or
termination of employment with the Corporation of any of the Shareholders, it
will be in the best interests of the Corporation that the Corporation acquire
all Shares of the Corporation owned by said Shareholder; and

          WHEREAS, in connection with the issuance of shares of the
Corporation's $0.01 par value Series A Convertible Preferred Stock pursuant to
the Securities Purchase Agreement dated as of November 18, 1998 between the
Corporation and the Purchasers named therein, each of the parties hereto has
become a Stockholder party to (i) the Registration Rights Agreement dated as of
November 18, 1998 among the Corporation and the Stockholders named therein and
(ii) the Stockholders Agreement dated as of November 18, 1998 among the
Corporation and the Stockholders named therein;
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          NOW, THEREFORE, the Shareholders and the Corporation agree as follows:

          1.      Scope of Agreement.

          For purposes of this Agreement the term "Shares" shall mean (i) all
shares of the Common Stock of the Corporation (now owned or hereafter acquired)
by the Employee Shareholders (as hereinafter defined) and (ii) all shares of the
Common Stock of the Corporation held by The Goldman Sachs Group, L.P. and Brooks
Investments, L.P. on the date hereof and listed on Exhibit A hereto.

          2.      Purchase Obligations Upon Death or Total Permanent Disability.


          2.1.    Death. Upon the death of a Shareholder, his estate shall have
an option to sell all of the Shares which the deceased Shareholder owned at his
death for the price as established pursuant to Section 7 herein and upon the
terms hereinafter provided. In addition, the Corporation shall have the option
to purchase all of the Shares which the deceased Shareholder owned at his death
for the price as established pursuant to Section 7 herein and upon the terms
hereinafter provided. The options described in this Section 2.1 shall be
exercisable by the estate of the deceased Shareholder or the Corporation (or the
Corporation's designee) upon the Shareholder's death and such options shall
remain exercisable for one hundred eighty (180) days unless one of such options
is exercised prior thereto. In the event both the Shareholder's option and the
Corporation's option are exercised on the same day, the Corporation's option
shall be deemed to be controlling. The options set forth in this Section 2.1
shall remain exercisable, notwithstanding any transfers proposed pursuant to
Section 3.

          2.2.    Disability. Upon total permanent disability of a Shareholder,
said disabled Shareholder shall have the option to sell all of the Shares owned
by the disabled Shareholder for the price as established pursuant to Section 7
herein and upon the terms hereinafter provided. In addition, the Corporation
shall have the option to purchase all of the Shares owned by the disabled
Shareholder for the price as established pursuant to Section 7 herein and upon
the terms hereinafter provided. The options described in the preceding sentence
shall be exercisable by the disabled Shareholder or the Corporation (or the
Corporation's designee), respectively, upon the occurrence of the shareholder's
disability. In the event both the Shareholder's option and the Corporation's
option are exercised on the same day, the Corporation's option shall be deemed
to be controlling. Total and permanent disability means having a physical or
mental condition resulting from injury, disease or mental disorder which, in the
opinion of a majority of the Board of Directors of the Corporation, makes a
Shareholder permanently incapable of continuing in the employment of the
Corporation. A determination by the disability insurance carrier for the
Corporation, if any, that a Shareholder is totally disabled shall be conclusive
upon the parties to this Agreement.

          2.3.    Exception. For purposes of Sections 2.1 and 2.2, the term
Shareholder shall not include Brooks Investments, L.P. or The Goldman Sachs
Group, L.P., so that any reference to the purchase and sale of Shares pursuant
to Sections 2.1 and 2.2 made in this Agreement shall not include the Shares
owned from time to time by Brooks Investments, L.P. or The Goldman Sachs Group,
L.P.


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          3.      Option Upon Voluntary Transfer.

          3.1.    Prohibition on Transfer During Start-up Phase. No Shareholder
may voluntarily transfer Shares of which he is the owner (other than to an
affiliate of such Shareholder) prior to the time the Corporation has issued
Shares for an aggregate consideration of not less than $10 million without the
approval of the Board of Directors. Thereafter, any voluntary transfer shall be
subject to this Section 3.

          3.2.    Notice of Transfer. If a Shareholder intends to transfer
Shares of which he is the owner to any person other than to the Corporation, he
shall give thirty (30) days written notice (the "Shareholder's Notice") to the
Corporation and the other Shareholder(s) of the proposed terms (including sales
price), conditions and manner of disposition, the number of Shares to be
disposed of and the person(s), firm(s) or corporation(s) to whom the selling
Shareholder proposes to transfer such Shares. The notice, in addition to stating
the fact of the intention to transfer Shares, shall state: (i) the number of
Shares to be transferred; (ii) the name, business and residence address of the
proposed transferee; and (iii) whether or not the transfer is for a valuable
consideration, and, if so, the amount of the consideration and the other terms
of sale.

          3.3.    Company Option to Purchase. Within sixty (60) days of the
Corporation's receipt of the Shareholder's Notice, the Corporation (or the
Corporation's designee) may exercise an option to purchase all or any portion of
the Shares proposed to be transferred for the sales price thereof as set forth
in the notice, and upon the other terms hereinafter provided.

          3.4.    Shareholders, Option to Purchase. If the Corporation does not
exercise its option to purchase all or any portion of such Shares, the remaining
Shareholder(s) within ninety (90) days of the Corporation's receipt of the
Shareholder's Notice, may exercise an option to purchase any portion of such
unpurchased Shares. Each remaining Shareholder shall have the right to purchase
a "proportionate share" of the total number of Shares proposed to be
transferred. The term "proportionate share" shall mean, with respect to each
electing Shareholder, that portion of the Shares proposed to be transferred
multiplied by a ratio, the numerator of which is the number or Shares which the
electing Shareholder then owns and the denominator of which is the total number
of Shares then owned by all electing Shareholders.

          3.5.    Complete Exercise. The Corporation and the electing
Shareholder(s) must in the aggregate exercise their options to purchase all of
the Shares proposed to be transferred or forfeit their options.

          3.6.    Intervening Death or Disability. If a Shareholder who proposes
to transfer Shares dies or becomes permanently disabled prior to the closing of
the sale and purchase contemplated by this Section 3, his Shares shall be
subject to sale and purchase under Section 2.

          3.7.    Permitted Transfers. Notwithstanding the provisions of this
Article 3, a Shareholder may transfer Shares to any of such Shareholder's
spouse, parents, siblings, children, grandchildren or affiliate, or a trust for
the benefit of any such person, without being subject to


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the options contained in Sections 3.3 and 3.4, subject to the following
conditions (except in the case of a transfer to an affiliate as to which
transfer only Section 3.7(e) shall apply):

          (a)       such transfer has received the prior approval of the Board
                    of Directors;

          (b)       the transferor Shareholder does not receive consideration in
                    excess of that originally paid by the transferor Shareholder
                    for such Shares;

          (c)       the transferor Shareholder retains all voting rights with
                    respect to the transferred Shares pursuant to an irrevocable
                    proxy in a form acceptable to the Board of Directors and
                    filed with the Secretary of the Corporation;

          (d)       the transferor Shareholder indemnifies the Corporation and
                    each of its officers and directors from any and all
                    liabilities arising out of the issuance or transfer of such
                    Shares on terms acceptable to the Board of Directors in its
                    sole discretion;

          (e)       the transferee agrees in writing to be bound by all the
                    terms and conditions of this Agreement; and

          (f)       for purposes of the options and obligations set forth herein
                    in the event of death, disability, voluntary transfers,
                    involuntary transfers and termination of employment, all
                    transferred Shares shall be deemed to be owned by the
                    transferor Shareholder and subject to the options and
                    obligations set forth herein.

          4.        Option Upon Involuntary Transfer.

          If other than by reason of a Shareholder's death or disability, Shares
are transferred by operation of law to any person other than to the Corporation
(such as, but not limited to, a property division in conjunction with a divorce
proceeding, a Shareholder's trustee in bankruptcy, a purchaser at any creditor's
or court sale), the Corporation (or the Corporation's designee) or the remaining
Shareholders, within seventy (70) days of the Corporation's receipt of actual
notice of the transfer may exercise an option to purchase all but not less than
all of the Shares so transferred in the same manner and upon the same terms as
provided in Section 3, with respect to Shares proposed to be transferred.

          5.        Termination of Employment.

          If, other than by reason of death or permanent disability, a
Shareholder theretofore employed by the Corporation (an "Employee Shareholder")
shall cease to be employed by the Corporation for any reason, then the
Corporation (or the Corporation's designee) shall have the right to purchase and
the Employee Shareholder shall sell, upon the Corporation's exercise of such
right, the Shares owned by such Shareholder at the price determined in
accordance with Section 7 hereof and on the terms otherwise set forth herein.


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          6.      Exercise of Options and Effect of Non-Exercise of Options.

          6.1.    The Corporation and the Shareholders who exercise an option
granted in Sections 3 or 4 shall do so by delivering written notice of their
exercise of the options within the time provided in said sections to the
proposed transferor or to the transferee in the case of Section 4.

          6.2.    If the purchase options are forfeited or not exercised in
compliance with Sections 3 or 4, then in the case of a proposed transfer under
Section 3, the Shares may be transferred, within ten (10) days after the
expiration of the option period granted to the other Shareholders, to the
transferee named in the notice required by Section 3, and upon the terms therein
stated, which Shares when so transferred shall be subject to the terms of this
Agreement. In the case of a transfer of Shares under Section 4, the Shares
shall, in the hands of the transferee, be subject to the terms of this
Agreement.

          6.3.    No Section 3 transfer shall be valid if the transfer is not
within the aforesaid ten (10) day period, or is not in accordance with the terms
or to the transferee stated in the notice required of the transferring
Shareholder by Section 3. In such a case the Shares shall remain subject to this
Agreement.

          6.4.    In the event a transferor in a Section 3 transfer reacquires
all or any portion of the transferred Shares, the Shares shall be subject to
this Agreement as if no transfer had been made.

          6.5.    A proposed transferor of Shares under Section 3, as a
Shareholder or a director, or both, of the Corporation, shall vote in favor of
the Corporation's exercise of the purchase options granted to it by this
Agreement at any meeting of Shareholders or Directors called for such purpose.

          6.6.    Notwithstanding anything to the contrary in Section 3, 4 or 5,
if the Corporation and the other Shareholders do not elect to exercise any
option under Section 3, 4 or 5 in full, the holders of shares of the
Corporation's Preferred Stock may elect to purchase any portion of such
unpurchased shares in the same manner and upon the same terms as provided in
Section 3 within ten (10) days after the expiration of the option period granted
to the other Shareholders.

          7.      Purchase Price.

          7.1.    Shareholder's Election on Death or Disability. For purposes of
any purchase of all of a Shareholder's Shares due to death pursuant to the
exercise of the Shareholder's option set forth in Section 2.1 or disability
pursuant to the exercise of the Shareholder's option set forth in Section 2.2,
the purchase price of all such Shareholder's Shares shall be the greater of (i)
the price determined by the Board of Directors of the Corporation pursuant to
Exhibit B of this Agreement, or (ii) the latest price per share at which Shares
were traded in an arm's-length transaction.


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                  7.2. Corporation's Election on Death or Disability. For
purposes of any purchase of all of a Shareholder's Shares due to death pursuant
to the exercise of the Corporation's option set forth in Section 2.1 or
disability pursuant to the exercise of the Corporation's option set forth in
Section 2.2, the per share purchase price of all such Shareholder's Shares shall
be equal to the appraised value of the Corporation divided by the total number
of issued and outstanding Shares at the time of the appraisal. If it becomes
necessary to appraise the Corporation pursuant to this Section 7.2, the
Corporation shall submit a list of not less than three independent appraisers
engaged in the practice of appraising businesses similar to the Corporation to
the estate of the deceased Shareholder or the disabled Shareholder, as the case
may be within ten (10) days of the notice of the Shareholder election. Within
ten (10) days of receipt of the appraiser list, the estate of the deceased
Shareholder or the disabled Shareholder, as the case may be, shall select one
appraiser to conduct the appraisal. If the estate of the deceased Shareholder or
the disabled Shareholder fails to select an appraiser within such period then
the Corporation shall select an appraiser from the appraiser list. The appraiser
shall use its best efforts to appraise the Corporation within sixty (60) days of
his selection, and the determination of the appraised value of the Corporation
by the selected appraiser shall be binding upon all parties hereto.

                  7.3.     Voluntary  Transfer.  For  purposes  of any  purchase
of any or all of a  Shareholder's Shares pursuant to Section 3 the purchase
price shall be as set forth in the Shareholder's Notice.

                  7.4.     Involuntary Transfer. For purposes of any purchase of
any or all of a Shareholder's Shares pursuant to Section 4, the purchase price
of Shares shall be the lesser of (i) the price determined by the Board of
Directors of the Corporation pursuant to Exhibit B of this Agreement, (ii) the
latest price per share at which Shares were traded in an arm's-length
transaction, or (iii) the price at which the Shares are being transferred.

                  7.5.     Termination of Employment. For purposes of any
purchase of any or all of an Employee Shareholder's Shares pursuant to Section
5, the purchase price of the Shares shall be the greater of (i) the price
determined by the Board of Directors of the Corporation pursuant to Exhibit B of
this Agreement, or (ii) the latest price per share at which shares were traded
in an arm's length transaction, unless such Employee Shareholder was terminated
for "cause," in which case the purchase price for the Shares shall be the lesser
of (i) the price determined by the Board of Directors of the Corporation
pursuant to Exhibit B of this Agreement, or (ii) the book value per share of the
Corporation as determined as of the end of the prior fiscal year.

                  8.       Payment of the Purchase Price and Other Payments.

                  8.1.     Cash Payment. The purchase price for Shares purchased
pursuant to Sections 2 and 4 shall be paid in cash at the closing except that at
the option of the purchasing party or parties, not more than seventy-five
percent (75%) of the purchase price may be deferred and at least twenty-five
percent (25%) shall be paid at the closing, provided, however, that if the
Corporation is the owner and beneficiary or only the beneficiary, whether
directly or indirectly,






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<PAGE>   7



of any insurance on the life of the deceased Shareholder, from whose estate the
Corporation is purchasing shares pursuant to Section 2, the purchase price for
Shares shall be paid in accordance with Section 8.4 of this Agreement. The
purchase price for shares purchased pursuant to Section 3 shall be on such terms
as set forth in the notice provided therein. The purchase price for shares
purchased pursuant to Section 5 shall be paid in cash at the closing.

                  8.2.   The deferred portion of the price shall be evidenced by
the promissory note of each purchasing party, shall be substantially the form
set forth in Exhibit C to this Agreement, shall bear interest at a rate of six
percent (6%) per annum and shall be payable in equal monthly installments for a
period not exceeding five years following the closing.


                  8.3.   Any Shares purchased pursuant to this Agreement and
financed by a note shall be pledged to the selling Shareholder as security for
the payment of the note by a Collateral Pledge Agreement, in the form attached
hereto as Exhibit D.

                  8.4.   If the Corporation is the owner and beneficiary or only
the beneficiary, whether directly or indirectly, of any insurance on the life of
a deceased Shareholder from whose estate the Corporation is purchasing shares,
an amount equal to the greater of the death benefits received by it under the
insurance policy or policies or twenty-five percent (25 %) of the purchase price
shall be paid in cash to the estate of the deceased Shareholder and applied to
the purchase price of the shares. The balance, if any, of the purchase price may
be deferred as provided herein. If the insurance proceeds exceed the purchase
price of the shares, the excess shall be paid to the estate of the deceased
Shareholder.

                  8.5.   Recapitalization. If at the time, as hereinafter set
forth, the Corporation is required to make payment for the Shares owned by the
deceased Shareholder's estate, a disabled Shareholder or a terminated Employee
Shareholder, and is prevented from so doing by law, to the extent that the
following action is not in violation of the law: (i) the entire available
surplus shall be used to pay for part of said Shares, and (ii) the Corporation
and the Shareholders shall promptly take all required action to enable the
Corporation to make such payment out of surplus, including, without limitation,
the recapitalization of the Corporation so as to reduce its capital and increase
its surplus, if recapitalization is necessary to accomplish the purposes of this
Agreement.

                  9.     The Closing.

                  9.1.   Time of Closing. In the case of the purchase of Shares
from a deceased Shareholder's estate under Section 2.1, the closing shall take
place forty-five (45) days after the exercise of the option provided therein
unless such Shares are being purchased at their appraised value pursuant to
Section 7.2, in which event the closing shall take place thirty (30) days after
the determination of the appraised value by the appraiser. In the case of the
purchase of Shares from a disabled Shareholder under Section 2.2, the closing
shall take place thirty (30) days after the determination of total and permanent
disability by the Corporation, unless such Shares are being purchased at their
appraised value pursuant to Section 7.2, in which event the closing shall take
place thirty (30) days after the determination of the appraised value by the
appraiser. In the case









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<PAGE>   8



of a purchase of Shares under Sections 3, 4 or 5, the closing of the sale and
purchase shall take place ten (10) days after the delivery to the selling
Shareholders or the Shareholder whose employment has been terminated of written
notice by the last of the purchasing party or parties to deliver such notice of
its, his or their exercise of the option or options to purchase said
Shareholder's Shares.

                  9.2.   Absence of Liens. All Shares shall be delivered to the
Corporation free and clear of all liens, claims and encumbrances excepting only
those for which provision is expressly made in this Agreement and said Shares
shall be transferred on the books of the Corporation to the purchaser or
purchasers.

                  9.3.   Sequence  of  Closings.  The  sale  and  purchase  of
Shares which the surviving or remaining Shareholders are to purchase shall take
place immediately prior to the sale and purchase of Shares, if any, which the
Corporation is to purchase.

                  10.    Legend on Certificates.

                  All Shares now or hereafter owned by the Shareholders of the
Corporation shall be subject to the provisions of this Agreement and the
certificate representing Shares, including Shares in the hands of permitted
transferees, shall bear the following legend:

                  "The sale, transfer or encumbrance of this certificate is
                  subject to an Agreement dated as of August 14, 1998. A copy of
                  this Agreement is on file in the office of the Secretary of
                  the Corporation. The Agreement provides, among other things,
                  for certain obligations to sell and to purchase the Shares
                  evidenced by this certificate, for a designated purchase
                  price. By accepting the Shares evidenced by this certificate
                  the holder agrees to be bound by said Agreement."

No Shareholder may pledge his Shares without the consent of the Board of
Directors.

                  11.    [intentionally omitted]

                  12.    [intentionally omitted]

                  13.    Termination.

                  13.1.  Events.  This  Agreement and all  restrictions  on the
 transfer of Shares created hereby shall terminate on the occurrence of any of
the following events:

                  (a)    The bankruptcy or dissolution of the Corporation;

                  (b)    A single Shareholder becoming the owner of all of the
                         Shares of the Corporation, which are then subject to
                         this Agreement;

                  (c)    A single Shareholder becoming the owner of at least
                         sixty-seven percent (67%) of the Shares of the
                         Corporation which are then subject to this









                                      -8-



<PAGE>   9



                         Agreement by reason of a transaction wherein the
                         remaining Shareholders had the opportunity to sell all
                         their Shares pursuant to Section 11;

                  (d)    The execution of a written instrument by the
                         Corporation and all of the Shareholders who then own
                         Shares subject to this Agreement which terminates the
                         same; or

                  (e)    The Corporation becoming subject to Section 12(g) or
                         15(d) of the Securities Exchange Act of 1934, as
                         amended (by reason of a public offering of equity
                         securities of the Corporation).

                  13.2. Life Insurance. Upon termination of this Agreement, for
any reason, each Shareholder shall have the right within thirty (30) days after
termination to purchase from the Corporation all insurance policies on his life
owned by the Corporation for cash in the amount of the cash surrender value
thereof and the unearned net premiums thereon, both amounts as of the date of
the termination of the Agreement.

                  13.3.    Effect.  The  termination  of this  Agreement  for
any reason shall not affect any right or remedy existing hereunder prior to the
effective date of its termination.

                  13.4.    Sale of Shares.  This  Agreement,  except the
provisions of Sections 14.1 and 14.2 shall terminate with respect to a
Shareholder upon the sale by such Shareholder of all of such Shareholder's
Shares.
                  14.      Covenant Not to Violate Corporate Confidences.

                  14.1. The Shareholders will have access to and will become
aware of confidential information and trade secrets, as the latter term is
defined in the Missouri Uniform Trade Secrets Act, including customer data,
files and business techniques not generally available to the public, and this
confidential information will be compiled by the Corporation at great expense
and over a great amount of time. For purposes of this Agreement, confidential
information shall include, without limitation, the business plan of the
Corporation delivered to each of the Shareholders. The parties acknowledge that
this confidential information will give the Corporation a competitive advantage
over other businesses in its field of endeavor and that the Corporation's
business will be greatly and irreparably damaged by the release or use of this
confidential information outside of its own business. Therefore, as a material
inducement to signing this Agreement, each Shareholder will not, while he or she
is a Shareholder and during the two (2) year period beginning on the closing
date for the sale of his or her Shares under this Agreement, either disclose or
divulge this confidential information to anyone or use this confidential
information in any manner to compete with the Corporation, except (i) to any
person who is a partner, managing director, director, officer, employee or
affiliate of such Shareholder who is involved in the investment pursuant to this
Agreement, who is consulted with respect to such investment, or who such
Shareholder determines otherwise needs to know such information (each, a
"Representative"), (ii) to any person acting as an advisor to such Shareholder
or a potential co-investor with (or potential transferee of) such Shareholder in
connection with such investment, only if such advisor executes a confidentiality
agreement with the Corporation that









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<PAGE>   10





contains provisions similar to this Section 14 and in a form reasonably
acceptable to the Corporation, (iii) with the consent of the Company or (iv)
pursuant to a subpoena, Civil Investigative Demand (or similar process), order,
statute, rule or other legal requirement promulgated or imposed by a court or by
a judicial, regulatory, self-regulatory or legislative body, organization,
agency or committee or otherwise in connection with any judicial or
administrative proceeding (including, in response to oral questions,
interrogatories or requests for information or documents) in which such
Shareholder is involved. Each Shareholder shall be responsible for any breach of
this paragraph by any Representative of such Shareholder with whom such
Shareholder shares any confidential information. It is recognized that the
provisions of this section 14.1 do not apply to information which (i) is or
becomes generally available to the public other than as a result of a disclosure
by a party hereto, (ii) was within the possession of a party hereto prior to its
being furnished to such party by or on behalf of the Corporation, provided that
the source of such information, to such parties knowledge, was not bound by a
confidentiality agreement with or other contractual, legal, or fiduciary
obligation of confidentiality to the Corporation with respect to such
information, or (iii) is or becomes available to such party on a
non-confidential basis from a source other than the Corporation, provided that
such source, to such party's knowledge, is not bound by a confidentiality
agreement with or other contractual, legal or fiduciary obligation of
confidentiality to the Corporation with respect to such information.

                  14.2. Each shareholder agrees that while he or she is a
Shareholder and during the two (2) year period beginning on the closing date for
the sale of his or her Shares under this Agreement such Shareholder shall not
knowingly solicit any material client or customer of the Corporation that was a
client or customer of the Corporation during the time in which the Shareholder
owned the Shares for the provision of competitive local exchange communications
services in competition with the Corporation. The parties acknowledge that The
Goldman Sachs Group, L.P. ("GS Group") plans to transfer a portion of its Shares
to GS Capital Partners III, L.P. ("GSCP") and certain affiliated funds and that
those entities would thereupon become Shareholders under this Agreement.
Notwithstanding anything herein to the contrary, (i) GS Group and its affiliates
may engage in any brokerage, investment advisory, financial advisory, research
activities, anti-raid advisory, merger advisory, financing, asset management,
trading, market making, arbitrage and other similar activities conducted in the
ordinary course of its business, (ii) nothing in this Section 14 shall restrict
any of GS Group or any of its affiliates (including GSCP or any of its
affiliated funds) from making any investment in any entity, provided, however,
that, upon receipt of a written inquiry from the Corporation as to whether any
of them has an equity investment in any specifically identified privately held
competitive local exchange communications company that competes or has publicly
announced plans to compete with the Corporation in any of its markets (a
"Competitive CLEC"), or an equity investment in any specifically identified
publicly held Competitive CLEC with respect to which any of them has filed a
Schedule 13D or a Schedule 13G report under the Securities Exchange Act of 1934,
then GS Group and/or GSCP, as the case may be, shall, to the extent permitted,
disclose to the Corporation whether it has made such investment, whether it has
a representative on the board of directors of such Competitive CLEC and whether
it is merely a passive investor or has a more active role in such Competitive
CLEC, (iii) the provisions contained in this Section 14 shall not in any manner
apply to or restrict any of the portfolio companies of GS Group, GSCP and/or















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<PAGE>   11

their respective affiliates, and (iv) the service on the board of directors or a
committee thereof of any entity by an individual designated by GS Group or any
of its affiliates shall not be deemed a violation of this paragraph except for
the service by such individual on the board of directors or a committee thereof
of any Competitive CLEC (in which event the designee of GS Group and its
affiliates shall either resign from the board of directors of the Corporation or
the board of directors of such other company).

          14.3. Each Shareholder agrees that at no time will such Shareholder
knowingly solicit for employment any person employed by the corporation at any
time during which said Shareholder or any permitted transferee thereof owned
Shares; provided, however, that the use of an independent employment agency (so
long as such agency is directed not to solicit such employees), advertisements
in publications or other general solicitations for employment not directed at
such employees and the hiring as a result thereof shall not be deemed a
violation of this paragraph.

          14.4. Each Shareholder hereby expressly acknowledges and agrees that
the business of the Corporation is highly competitive and that a violation of
any of the covenants provided for in this Section 14 would cause immediate and
irreparable harm, loss and damage to the Corporation not adequately compensable
by a monetary award. Without limiting any of the other remedies available to the
Corporation, each Shareholder agrees that any actual or threatened violation of
said covenants, or any of them, may be immediately enjoined or restrained by any
court of competent jurisdiction, and that any temporary restraining order or
emergency, preliminary or final injunctions may be issued by any court of
competent jurisdiction, without notice and without bond. In the event any
proceedings are initiated by the Corporation against the Shareholder for any
actual or threatened violation of any of said covenants, the Shareholder shall
be liable to the Corporation for, and shall pay to the Corporation, all costs
and expenses of any kind which it may incur in connection with the proceedings,
including without limitation, reasonable attorneys' fees.

          15. Additional Agreements.

          15.1. [intentionally omitted]

          16. General Provisions.

          16.1. Governing Law. This Agreement shall be construed pursuant to the
laws of the State of Missouri.

          16.2. Definitions. Unless the context otherwise requires, the words
"Shareholder" and "Shareholders" shall for all purposes of this Agreement mean
and include: (1) all of the parties hereto; (2) all persons to whom any Shares
may hereafter be transferred; and (3) all employees who may acquire any Shares
of the Corporation which may hereafter be issued.

          16.3. Remedies for Breach. The Shares are unique chattels and each
party to this Agreement shall have the remedies which are available to him or it
for the violation of any of

                                      -11-

<PAGE>   12

the terms of this Agreement, including, but not limited to, the equitable
remedies for specific performance and injunctive relief.

          16.4. Notices. All notices provided for by this Agreement shall be
made in writing (1) either by actual delivery or (2) by the mailing of the
notice in the United States mail to the last known address of the party entitled
thereto, registered or certified mail, return receipt requested.

          16.5. Amendment. This Agreement may be amended or altered at any time
if the amendment or alteration is both ratified by the Board of Directors of the
Corporation and consented to in writing by Shareholders who are parties to this
Agreement and who collectively own not less than eighty percent (80%) of the
Corporation's Shares.

          16.6. Descriptive Headings. Titles to sections are for information
purposes only.

          16.7. Binding Effect. This Agreement is binding upon and inures to the
benefit of the Corporation, its successors, assigns, and transferees, and to the
Shareholders and their respective heirs, personal representatives, successors
and permitted assigns and transferees.

          16.8. Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original and all of which,
when taken together, shall be deemed to be one and the same agreement. This
Agreement shall become binding when one or more counterparts taken together
shall have been executed and delivered by all of the parties.

          IN WITNESS WHEREOF, the Corporation and the Shareholders have executed
this Agreement on the day and year above written.

                                        GABRIEL COMMUNICATIONS, INC.

                                        By    /s/ Gerard J. Howe
                                           ----------------------------------
                                            Gerard J. Howe, President

ATTEST:

   /s/ John P. Denneen
------------------------------------
John P. Denneen, Secretary


Individuals:

   /s/ Robert A. Brooks                       /s/ Kevin Keaveny
------------------------------------    ------------------------------------
Robert A. Brooks                        Kevin Keaveny



                                      -12-


<PAGE>   13



    /s/ Brian Butler                         /s/ Brett Kirby
------------------------------------    ------------------------------------
Brian Butler                            Brett Kirby

    /s/ Barbara Clements                    /s/ Timothy Tettambel
------------------------------------    ------------------------------------
Barbara Clements                        Timothy Tettambel

    /s/ Gary Eaves                          /s/ Janet Wendel
------------------------------------    ------------------------------------
Gary Eaves                              Janet Wendel

    /s/ Thomas Erickson
------------------------------------
Thomas Erickson

    /s/ Marguerite Forrest
------------------------------------
Marguerite Forrest

    /s/ Gerard Howe
------------------------------------
Gerard Howe



                                      -13-

<PAGE>   14


INSTITUTIONS:


BROOKS INVESTMENTS, L.P.                  GS Capital Partners III, L.P.
By:  Brooks Investments, Inc.,            By:  GS Advisors III, L.P.
         General Partner                          General Partner
                                          By:  GS Advisors III, L.L.C.
By:    /s/ Robert A. Brooks                       General Partner
   ---------------------------------
           Robert A. Brooks
           General Partner                By:  /s/ Eve M. Gerriets
                                             -------------------------------
                                          Its:  Vice President

THE GOLDMAN SACHS GROUP, L.P,             GS CAPITAL PARTNERS III OFFSHORE, L.P.
By:  The Goldman Sachs Corporation        By:  GS Advisors III (Cayman), L.P.
                                                  General Partner
By:    /s/ Joseph L. Glebelman            By:  GS Advisors III, L.L.C.
   ---------------------------------              General Partner
Its:   Executive Vice President

                                          By:    /s/ Eve M. Gerriets
                                              -------------------------------
                                          Its:  Vice President

GOLDMAN, SACHS & CO. VERWALTUNGS GmbH


By:    /s/ Joseph Glebelman
   ------------------------------------
            Managing Director

By:   /s/ Eve M. Gerriets
   ---------------------------------
            Registered Agent




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

By:   /s/ Eve M. Gerriets
   ---------------------------------
Its:  Vice President

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

By:    /s/ Eve M. Gerriets
   ---------------------------------
Its:  Vice President




                                      -14-


<PAGE>   15

                                   EXHIBIT "A"

                        SHARES OWNED BY THE SHAREHOLDERS

<TABLE>
<CAPTION>

NAME OF SHAREHOLDER                          NUMBER OF SHARES OWNED
-------------------                          ----------------------
<S>                                          <C>
Robert A. Brooks                                            150,000
Brian Butler                                                300,000
Barbara Clements                                            120,000
Gary Eaves                                                   30,000
Thomas Erickson                                             400,000
Marguerite Forest                                           300,000
Gerard Howe                                                 450,000
Kevin Keaveny                                               240,000
Brett Kirby                                                  20,000
Timothy Tettambel                                           240,000
Janet Wendel                                                110,000
Brooks Investments, L.P.                                  2,000,000
The Goldman Sachs Group, L.P.                               840,000

</TABLE>





<PAGE>   16
                                   EXHIBIT "B"

                       DETERMINATION OF THE PURCHASE PRICE

         1. The price of Shares to be purchased under this Agreement shall be
their Fair Market Value.

         2. The term "Fair Market Value" as used in paragraph 1 of this Exhibit
B shall be an amount which bears the same proportion to the amount of the Net
Worth of the Corporation as the number of Shares to be purchased bears to the
total number of the Corporation's Shares outstanding.

         3. The Board of Directors of the Corporation shall from time to time,
but no less often than annually, agree upon and determine, by majority vote, the
"Net Worth" as used in paragraph 2 of this Exhibit B as of the close of business
on a specified date. The Net Worth so established shall be included in the
minutes of the meeting of the Board of Directors. If the Board of Directors
fails to determine the Net Worth for any period in excess of one year, the value
last previously agreed upon shall be the Net Worth. If the Shareholders fail to
determine the Net Worth for two successive years, the most current agreed "Net
Worth" shall be either increased or decreased by any increase or decrease in the
book value of the Corporation since the Net Worth was last established.

         4. The pro forma Net Worth of the Corporation as of the September 30,
1998 (i) giving effect to the issuance of 150,000 shares in October 1998 at
$0.50 per share is $2,427,000 and the book value per share of the 5,200,000
Shares outstanding as of the date hereof is $0.47 per share and (ii) giving
effect to the subscriptions for 16,849,999 shares of Series A Preferred Stock at
$3.00 per share on November 18, 1998 the book value per share of the 5,200,000
Shares outstanding on November 18, 1998 is $2.40 per share.





<PAGE>   17





                                   EXHIBIT "C"



                                 PROMISSORY NOTE



                                                                         , 199
$

For value received, the undersigned promises to pay                       or
order the sum of $                  at              , with interest at
              percent (     %) per annum, in installments payable as follows:
Monthly payments in the sum $            , the first payment to be made on the
    day of           , 199   and a like amount on the      day of
               , each succeeding month thereafter with the final payment on the
then outstanding principal balance to be made on the     day of             ,
199   .

                  The interest on each installment, and the interest on the
unpaid balance of the principal sum are to be paid at the maturity of each
installment. If default is made in the payment of any installment whether
interest or principal, when due, then all the remaining installments shall, at
the option of the holder, become due and payable at once. In case suit shall be
brought on this Note, the Maker agrees to pay the Holder's reasonable attorney's
fees and Court costs. This Note and all installments are to bear interest after
maturity thereof at the rate of               percent (    %) per annum. All
signers, endorsers, guarantors and parties to this instrument hereby waive
demand, protest and notice of nonpayment and agree to all extensions and partial
payments before or after maturity.



                                                    GABRIEL COMMUNICATIONS, INC.



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


ATTEST:

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


<PAGE>   18





                                   EXHIBIT "D"

                           COLLATERAL PLEDGE AGREEMENT



                  In consideration of, and as collateral security for the
payment of, the liabilities of                        (the "Pledgor"), to
                     (the "Pledgee") evidenced by or arising in connection with
(1) a certain Shareholders Agreement entered into between Pledgor and Pledgee on
          , 1998, and (2) a certain Promissory Note of even date herewith
executed by the Pledgor and payable to Pledgee and all renewals and extensions
of such liabilities (herein collectively called the Liabilities"), Pledgor
hereby assigns, pledges and delivers to Pledgee               shares of the
common stock of Gabriel Communications, Inc. and grants Pledgee a continuing
security interest in said shares, together with all proceeds thereof,
substitutions therefor and rights associated therewith (referred to collectively
herein as the "Collateral"), all of which the Pledgor owns free of liens or
claims of any kind and has the right to pledge to Pledgee.

Pledgor hereby agrees that the Collateral shall constitute security for any and
all of the Liabilities. Pledgor authorizes Pledgee to cause any Collateral to be
transferred, in such manner and at such time(s) as Pledgee may determine, into
the names of Pledgee or Pledgee's nominees and this instrument shall constitute
Pledgee's authority to make such transfer(s).

                  Pledgor agrees that:

                  (1)      Pledgor will execute, endorse and deliver all
                           documents which Pledgee may reasonably require to
                           secure Pledgee's interests under this Collateral
                           Pledge Agreement.

                  (2)      Pledgor shall have no right to call, exchange,
                           convert or otherwise change or alter the form of the
                           Collateral without the consent of Pledgee so long as
                           any portion of the Liabilities remain unpaid. Any
                           dividend, increase or distribution paid in cash out
                           of the earnings of the issuer on any stock
                           constituting a part of the Collateral shall be
                           released to Pledgor by Pledgee unless such Collateral
                           is transferred into the name of Pledgee or Pledgee's
                           nominee, and Pledgor shall retain all voting rights
                           with respect to such Collateral, except in the case
                           of a default as defined herein. Any instruments,
                           securities, rights or the like which an owner of the
                           Collateral has the right to receive by way of stock
                           split-up, stock dividend, warrants or other increase
                           in the Collateral (except dividends as set forth
                           above) will be delivered to Pledgee and Pledgee may,
                           without notice or demand, take such action as is
                           necessary to assure Pledgor's direct receipt thereof.

                  (3)      The following events shall severally be considered
                           events of default: (a) material misrepresentation of
                           any fact or warranty stated or made to Pledgee by
                           Pledgor, (b) failure by Pledgor to perform any term
                           or
<PAGE>   19

                           provision of this or any other agreement with
                           Pledgee, (c) default in the payment of any sum due on
                           any of the Liabilities, (d) Pledgor's insolvency,
                           adjudication of bankruptcy, making an assignment for
                           the benefit of creditors or suffering appointment of
                           a receiver or seeking relief under any debtor's
                           relief law, (e) seizure of the Collateral by lawful
                           execution or the sale or encumbrance thereof (except
                           as provided herein), failure to pay any tax thereon
                           when due except any tax contested in good faith) or
                           default on any debt or security instrument
                           constituting part of the Collateral. Upon any such
                           event of default all of the Liabilities shall, at the
                           option of Pledgee, become immediately due and payable
                           and Pledgee may without notice or demand (i) offset
                           any obligations of Pledgee to Pledgor against any of
                           the Liabilities and (ii) forthwith realize upon the
                           Collateral or any part thereof and receive the
                           proceeds therefrom, and may also, without demand,
                           advertisement or notice, sell at public or private
                           sale, or at any exchange or broker's board, at such
                           prices and upon such terms and conditions as Pledgee
                           may deem best, either for cash or on credit, or for
                           future delivery, any part or all of such Collateral.
                           Pledgee shall have the right, at any such sale,
                           public or private, to purchase the whole or any part
                           of such Collateral so sold, provided that any excess
                           of such Collateral or proceeds thereof over the
                           amount of the Liabilities shall be returned to the
                           Pledgor.

                  (4)      In addition, Pledgee shall have all rights of a
                           secured party under the Missouri Uniform Commercial
                           Code and shall first be entitled to apply the
                           proceeds of collection, disposition or other
                           realization on the Collateral to reasonable
                           attorneys, fees and legal expenses incurred by
                           Pledgee in the collection of any Liabilities, and
                           thereafter as required by law.

                  (5)      If notice of default or of intended disposition is
                           required by law, then such notice, if mailed, shall
                           be deemed reasonably and properly given if mailed by
                           or on behalf of Pledgee to the principal business
                           address of Pledgor at least ten (10) days before the
                           time of such disposition. If in the opinion of
                           Pledgee any Collateral cannot be disposed of in a
                           commercially reasonable manner without registration
                           under applicable securities laws, Pledgor will take
                           or cause to be taken such action as is necessary to
                           effect proper registration, and if Pledgor shall
                           refuse to take such action, Pledgee, at his or her
                           sole election, but without any obligation to do so,
                           may take such action as he or she deems warranted to
                           effect or attempt to effect compliance with any
                           applicable law and any cost incurred by Pledgee in
                           connection therewith or in enforcing Pledgor's
                           agreement will be considered a cost incurred in
                           disposition of the Collateral.

                  (6)      Pledgee's rights hereunder shall continue unimpaired
                           notwithstanding foreclosure or other disposition of
                           any part of the Collateral, the availability of
                           additional Collateral, any release of or substitution
                           for any

<PAGE>   20


                           of the Collateral, any act or omission impairing
                           Pledgee's lien on the Collateral or the lien of any
                           underlying security constituting part of the
                           Collateral, including failure to perfect the same,
                           any extension (including extension of time for
                           payment), renewal, substitution, alteration,
                           compromise, settlement, surrender or other such
                           agreement or action transferring, modifying or
                           varying the terms of or otherwise affecting any of
                           the Liabilities or any part of the Collateral,
                           including any act or omission releasing any party
                           primarily or secondarily liable on the Collateral or
                           on any of the Liabilities. No failure by Pledgee to
                           exercise or delay in exercising any of his or her
                           rights hereunder shall constitute a waiver thereof by
                           Pledgee and no single or partial exercise of any
                           right shall preclude the further exercise thereof or
                           the exercise of any other right from time to time.
                           All rights granted to Pledgee hereunder are
                           cumulative and not in substitution of any other
                           rights at law or equity with respect to the
                           Collateral or the collection of the Liabilities.
                           Pledgor hereby waives notice of any and all actions,
                           forbearances and omissions of any rights contemplated
                           by this paragraph and consents to be bound thereby as
                           effectively as if Pledgor had agreed thereto in
                           advance.

                  (7)      Pledgee may assign or negotiate and deliver any of
                           the Collateral to any transferee of any of the
                           Liabilities and Pledgee shall thereafter be relieved
                           of any responsibility for the Collateral so
                           transferred and all rights of Pledgee hereunder shall
                           inure to his or her transferees.

                  (8)      This Agreement shall be governed by Missouri law and
                           the rights and obligations hereunder shall inure to
                           the benefit of and be binding upon the parties hereto
                           and their respective heirs, assigns, legatees,
                           transferees and legal representatives.



                                     -------------------------------------------
                                     Pledgor