REGISTRATION RIGHTS AGREEMENT
                         -----------------------------


This Agreement dated as of February 29, 1996 is entered into by and among Radio
Telephone Systems, Inc. d/b/a Boston Communications Group, a Massachusetts
corporation (the "Company"), and Michael J. Buchel, Zuyus Investment Company,
John M. Freese, Joseph Giegerich, Terence G. Hare III, J. Michael Looney and
John M. Freese, Sr.(the "Initial Stockholders").

WHEREAS, the Company and the Initial Stockholders have entered into a Merger
Agreement of even date herewith (the "Merger Agreement"); and

WHEREAS, the Company and the Initial Stockholders desire to provide for certain
arrangements with respect to the registration of shares of capital stock of the
Company under the Securities Act of 1933; subject to certain pre-existing
registration rights granted by the Buyer to its current preferred stockholders;

NOW, THEREFORE, in consideration of the mutual promises and covenants contained
in this Agreement, the parties hereto agree as follows:

1. Certain Definitions.  As used in this Agreement, the following terms shall
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have the following respective meanings:

     "Commission" means the Securities and Exchange Commission, or any other
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     Federal agency at the time administering the Securities Act.

     "Common Stock" means the common stock, $.0l par value per share, of the
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     Company.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended, or
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     any similar Federal statute, and the rules and regulations of the
     Commission issued under such Act, as they each may, from time to time, be
     in effect.

     "Registration Statement" means a registration statement filed by the
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     Company with the Commission for a public offering and sale of Common Stock
     (other than a registration statement on Form S-8 or Form S-4, or their
     successors, or any other form for a similar limited purpose, or any
     registration statement covering only securities proposed to be issued in
     exchange for securities or assets of another corporation).

     "Registration Expenses" means the expenses described in Section 4.
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     "Registrable Shares" means (i) the shares of Common Stock issued or
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     issuable to the Stockholders pursuant to the Merger Agreement and any other
     shares of Common Stock issued in respect of such shares (because of stock
     splits, stock dividends, reclassifications, recapitalizations, or similar
     events); provided, however, that shares of Common Stock which are
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     Registrable Shares shall cease to be Registrable Shares (i) upon any sale
     pursuant to a Registration Statement or Rule 144 under the Securities Act
     or (ii) upon any sale in any manner to a person or entity which, by virtue
     of Section 12 of this Agreement, is not entitled to the rights provided by
     this Agreement.

 
     "Securities Act" means the Securities Act of 1933, as amended, or any
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     similar Federal statute, and the rules and regulations of the Commission
     issued under such Act, as they each may, from time to time, be in effect.

     "Stockholders" means the Initial Stockholders and any persons or entities
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     to whom the rights granted under this Agreement are transferred by any
     Initial Stockholders, their successors or assigns pursuant to Section 12
     hereof.

2.   Registration Rights.
     ------------------- 

     (a)  Whenever the Company proposes to file a Registration Statement at any
     time and from time to time, it will, prior to such filing, give written
     notice to all Stockholders of its intention to do so and, upon the written
     request of a Stockholder or Stockholders given within 20 days after the
     Company provides such notice, the Company shall use its best efforts to
     cause all Registrable Shares which the Company has been requested by such
     Stockholder or Stockholders to register to be registered under the
     Securities Act; provided that the Company shall have the right to postpone
     or withdraw any registration effected pursuant to this Section 2 without
     obligation to any Stockholder, and that the right of the Stockholders to
     participate in such a registration shall be subject to and in accordance
     with the registration rights granted by the Buyer to its current preferred
     stockholders prior to the date of this Agreement.

     (b)  In connection with any registration under this Section 2 involving an
     underwriting, the Company shall not be required to include any Registrable
     Shares in such registration unless the holders thereof accept the terms of
     the underwriting as agreed upon between the Company and the underwriters
     selected by it (provided that such terms must be consistent with this
     Agreement).  If in the opinion of the managing underwriter it is
     appropriate because of marketing factors to limit the number of Registrable
     Shares to be included in the offering, then the Company shall be required
     to include in the registration only that number of Registrable Shares, if
     any, which the managing underwriter believes should be included therein;
     provided that no reduction in the number of Registrable Shares to be
     included in the offering shall be made unless such reduction represents a
     proportionate reduction which is no greater than the proportionate
     reduction of shares of Common Stock requested to be included in the
     registration by other holders of securities entitled to registration who
     are officers of the Buyer.

3.   Registration Procedures.  If and whenever the Company is required by the
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provisions of this Agreement to use its best efforts to effect the registration
of any of the Registrable Shares under the Securities Act, the Company shall:

     (a)  file with the Commission a Registration Statement with respect to such
     Registrable Shares and use its best efforts to cause that Registration
     Statement to become and remain effective;

     (b)  as expeditiously as possible prepare and file with the commission any
     amendments and supplements to the Registration Statement and the prospectus
     included in the Registration Statement as may be necessary to keep the
     Registration Statement effective, in the case of a firm commitment
     underwritten public offering, until each underwriter has completed the
     distribution of all securities purchased by it and, in the case of any
     other offering, until the earlier of the sale of all Registrable Shares
     covered thereby or 120 days after the effective date thereof;

 
     (c)  as expeditiously as possible furnish to each selling Stockholder such
     reasonable numbers of copies of the prospectus, including a preliminary
     prospectus, in conformity with the requirements of the Securities Act, and
     such other documents as the selling Stockholder may reasonably request in
     order to facilitate the public sale or other disposition of the Registrable
     Shares owned by the selling Stockholder; and

     (d)  as expeditiously as possible use its best efforts to register or
     qualify the Registrable Shares covered by the Registration Statement under
     the securities or Blue Sky laws of such states as the selling Stockholders
     shall reasonably request, and do any and all other acts and things that may
     be necessary or desirable to enable the selling Stockholders to consummate
     the public sale or other disposition in such states of the Registrable
     Shares owned by the selling Stockholder; provided, however, that the
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     Company shall not be required in connection with this paragraph (d) to
     qualify as a foreign corporation or execute a general consent to service of
     process in any Jurisdiction.

     If the Company has delivered preliminary or final prospectuses to the
     selling Stockholders and after having done so the prospectus is amended to
     comply with the requirements of the Securities Act, the Company shall
     promptly notify the selling Stockholders and, if requested, the selling
     Stockholders shall immediately cease making offers of Registrable Shares
     and return all prospectuses to the Company.  The Company shall promptly
     provide the selling Stockholders with revised prospectuses and, following
     receipt of the revised prospectuses, the selling Stockholders shall be free
     to resume making offers of the Registrable Shares.

4.   Allocation of Expenses.  The Company will pay all Registration Expenses of
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all registrations under this Agreement.  For purposes of this Section 4, the
term "Registration Expenses" shall mean all expenses incurred by the Company in
Complying with this Agreement, including, without limitation, all registration
and filing fees, exchange listing fees, printing expenses, fees and expenses of
counsel for the Company, and the expense of any special audits incident to or
required by any such registration, but excluding underwriting discounts, selling
commissions and the fees and expenses of selling Stockholders' counsel.

5.   Indemnification and Contribution.
     -------------------------------- 

     (a)  In the event of any registration of any of the Registrable Shares
     under the Securities Act pursuant to this Agreement, the Company will
     indemnify and hold harmless the seller of such Registrable Shares, each
     underwriter of such Registrable Shares, and each other person, if any, who
     controls such seller or underwriter within the meaning of the Securities
     Act or the Exchange Act against any losses, claims, damages or liabilities,
     joint or several, to which such seller, underwriter or controlling person
     may become subject under the Securities Act, the Exchange Act, state
     securities or Blue Sky laws or otherwise, insofar as such losses, claims,
     damages or liabilities (or actions in respect i thereof) arise out of or
     are based upon any untrue statement or alleged untrue statement of any
     material fact contained in any Registration Statement under which such
     Registrable Shares were registered under the Securities Act, any
     preliminary prospectus or final prospectus contained in the Registration
     Statement, or any amendment or supplement to such Registration Statement,
     or arise out of or are based upon the omission or alleged omission to state
     a material fact required to be stated therein or necessary to make the
     statements therein not misleading; and the Company will reimburse such
     seller, underwriter and each such controlling person for any legal or any
     other expenses reasonably incurred by such seller, underwriter or
     controlling person in connection with investigating or defending any such
     loss, claim, damage, liability or action; provided, however, that the
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     Company will not be liable in

 
     any such case to the extent that any such loss, claim, damage or liability
     arises out of or is based upon any untrue statement or omission made in
     such Registration Statement, preliminary prospectus or final prospectus, or
     any such amendment or supplement, in reliance upon and in conformity with
     information furnished to the Company, in writing, by or on behalf of such
     seller, underwriter or controlling person specifically for use in the
     preparation thereof.

     (b)  In the event of any registration of any of the Registrable Shares
     under the Securities Act pursuant to this Agreement, each seller of
     Registrable Shares, severally and not jointly, will indemnify and hold
     harmless the Company, each of its directors and officers and each
     underwriter (if any) and each person, if any, who controls the Company or
     any such underwriter within the meaning of the Securities Act or the
     Exchange Act, against any losses, claims, damages or liabilities, joint or
     several, to which the Company, such directors and officers, underwriter or
     controlling person may become subject under the Securities Act, Exchange
     Act, state securities or Blue Sky laws or otherwise, insofar as such
     losses, claims, damages or liabilities (or actions in respect thereof)
     arise out of or are based upon any untrue statement or alleged untrue
     statement of a material fact contained in any Registration Statement under
     which such Registrable Shares were registered under the Securities Act, any
     preliminary prospectus or final prospectus contained in the Registration
     Statement, or any amendment or supplement to the Registration Statement, or
     arise out of or are based upon any omission or alleged omission to state a
     material fact required to be stated therein or necessary to make the
     statements therein not misleading, if the statement or omission was made in
     reliance upon and in conformity with information relating to such seller
     furnished in writing to the Company by or on behalf of such seller
     specifically for use in connection with the preparation of such
     Registration Statement, prospectus, amendment or supplement;
     provided, however, that the obligations of such Stockholders hereunder
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     shall be limited to an amount equal to the proceeds to each Stockholder of
     Registrable Shares sold in connection with such registration.

     (c)  Each party entitled to indemnification under this Section 5 (the
     "Indemnified Party") shall give notice to the party required to provide
     indemnification (the "Indemnifying Party") promptly after such Indemnified
     Party has actual knowledge of any claim as to which indemnity may be
     sought, and shall permit the Indemnifying Party to assume the defense of
     any such claim or any litigation resulting therefrom; provided, that
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     counsel for the Indemnifying Party, who shall conduct the defense of such
     claim or litigation, shall be approved by the Indemnified Party (whose
     approval shall not be unreasonably withheld); and, provided, further, that
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     the failure of any Indemnified Party to give notice as provided herein
     shall not relieve the Indemnifying Party of its obligations under this
     Section 5. The Indemnified Party may participate in such defense at such
     party's expense; provided, however, that the Indemnifying Party shall pay
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     such expense if representation of such Indemnified Party by the counsel
     retained by the Indemnifying Party would be inappropriate due to actual or
     potential differing interests between the Indemnified Party and any other
     party represented by such counsel In such proceeding.  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 of such claim or litigation, and
     no Indemnified Party shall consent to entry of any judgment or settle such
     claim or litigation without the prior written consent of the Indemnifying
     Party.

     (d)  In order to provide for just and equitable contribution to joint
     liability under the Securities Act in any case in which either (i) any
     holder of Registrable Shares exercising rights under this Agreement, or any
     controlling person of any such holder, makes a claim for

 
     indemnification pursuant to this Section 5 but it is judicially determined
     (by the entry of a final judgment or decree by a court of competent
     jurisdiction and the expiration of time to appeal or the denial of the last
     right of appeal) that such indemnification may not be enforced in such case
     notwithstanding the fact that this Section 5 provides for indemnification
     in such case, or (ii) contribution under the Securities Act may be required
     on the part of any such selling Stockholder or any such controlling person
     in circumstances for which indemnification is provided under this Section
     5; then, in each such case, the Company and such Stockholder will
     contribute to the aggregate losses, claims, damages or liabilities to which
     they may be subject (after contribution from others) in such proportions so
     that such holder is responsible for the portion represented by the
     percentage that the public offering price of its Registrable Shares offered
     by the Registration Statement bears to the public offering price of all
     securities offered by such Registration Statement, and the Company is
     responsible for the remaining portion; provided, however, that, in any such
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     case, (A) no such holder will be required to contribute any amount in
     excess of the proceeds to it of all Registrable Shares sold by it Pursuant
     to such Registration Statement, and (B) no person or entity guilty of
     fraudulent misrepresentation, within the meaning of Section 11(f) of the
     Securities Act, shall be entitled to contribution from any person or entity
     who is not guilty of such fraudulent misrepresentation.

6.   Information by Holder.  Each Stockholder including Registrable Shares in
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any registration shall furnish to the Company such information regarding such
Stockholder and the distribution proposed by such Stockholder as the Company may
reasonably request in writing and as shall be required in connection with any
registration, qualification or compliance referred to in this Agreement.

7.   "Stand-Off" Agreement.  Each Stockholder, if requested by the Company and
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the managing underwriter of an offering by the company of Common Stock or other
securities of the Company pursuant to a Registration Statement, shall agree not
to sell publicly or otherwise transfer-or dispose of any Registrable Shares or
other securities of the Company held by such Stockholder for a specified period
of time (not to exceed 180 days) following the effective date of such
Registration Statement; -provided, that:
                        ---------       

     (a)  such agreement sh all only apply to the first Registration Statement
     covering Common Stock to be sold on its behalf to the public in an
     underwritten offering; and

     (b)  all Stockholders holding not less than        the number of shares of
     Common Stock held by such Stockholder (including shares of Common Stock
     issuable upon the conversion of Shares, or other convertible securities, or
     upon the exercise of options, warrants or rights) and all officers and
     directors of the Company enter into similar agreements.

8.   Rule 144 Requirements.  After the earliest of (i) the closing of the sale
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of securities of the Company pursuant to a Registration Statement, (ii) the
registration by the Company of a class of securities under Section 12 of the
Exchange Act, or (iii) the issuance by the Company of an offering circular
pursuant to Regulation A under the Securities Act, the Company agrees to:

     (a)  comply with the requirements of Rule 144(c) under the Securities Act
     with respect to current public information about the Company;

     (b)  use its best efforts to file with the Commission in a timely manner
     all reports and other documents required of the Company under the
     Securities Act and the Exchange Act (at any time after it has become
     subject to such reporting requirements); and

 
     (c)  furnish to any holder of Registrable Shares upon request (i) a written
     statement by the Company as to its compliance with the requirements of said
     Rule 144(c), and the reporting requirements of the Securities Act and the
     Exchange Act (at any time after it has become subject to such reporting
     requirements), (ii) a copy of the most recent annual or quarterly report of
     the Company, and (iii) such other reports and documents of the Company as
     such holder may reasonably request to avail itself of any similar rule or
     regulation of the Commission allowing it to sell any such securities
     without registration.

9.   Termination.  All of the Company's obligations to register Registrable
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Shares under this Agreement shall terminate on the tenth anniversary of this
Agreement.

10.  Transfers of Rights.  This Agreement, and the rights and obligations of
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each Initial Stockholder hereunder, may be assigned by such Initial Stockholder
to any person or entity to which Shares are transferred by such Initial
Stockholder, and such transferee shall be deemed an "Initial Stockholder" for
purposes of this Agreement; provided that the transferee provides written notice
of such assignment to the Company.

11.  General.
     ------- 

     (a) Notices.  All notices, requests, consents, and other communications
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     under this Agreement shall be in writing and shall be delivered by hand or
     mailed by first class certified or registered mail, return receipt
     requested, postage prepaid:

     If to the Company, at Boston Communications Group, One McKinley Square, 3rd
     Floor, Boston, MA 02109, Attention: Alan J. Bouffard, Esq., or at such
     other address or addresses as may have been furnished in writing by the
     Company to the Stockholders, with a copy to Thomas L. Barrette, Jr., Esq.,
     Hale and Dorr, 60 State Street, Boston, MA 02109; or

     If to a Stockholder, at his or its address set forth below his signature,
     or at such other address or addresses as may have been furnished to the
     Company in writing by such Stockholder, with a copy to John M. Freese, Sr.,
     Esq., Freese & March, P.A., 4310 East 31st Street, Tulsa, OK 74135.

     Notices provided in accordance with this Section 11(a) shall be deemed
     delivered upon personal delivery or two business days after deposit in the
     mail.

     (b) Entire Agreement.  This Agreement embodies the entire agreement and
         ----------------                                                   
     understanding between the parties hereto with respect to the subject matter
     hereof and supersedes all prior agreements and understandings relating to
     such subject matter.

     (c) Amendments and Waivers.  Any term of this Agreement may be amended and
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     the observance of any term of this Agreement may be waived (either
     generally or in a particular instance and either retroactively or
     prospectively), with the written consent of the Company and the holders of
     at least 60% of the Registrable Shares; provided, that this Agreement may
                                             --------                         
     be amended with the consent of the holders of less than all Registrable
     Shares only in a manner which affects all Registrable Shares in the same
     fashion.  No waivers of or exceptions to any term, condition or provision
     of this Agreement, in any one or more instances, shall be deemed to be, or
     construed as, a further or continuing waiver of any such term, condition or
     provision.

 
     (d) Counter-parts.  This Agreement may be executed in one or more
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     counterparts, each of which shall be deemed to be an original, but all of
     which shall he one and the same document.

     (e) Severability.  The invalidity or unenforceability of any provision of
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     this Agreement shall not affect the validity or enforceability of any other
     provision of this Agreement.

     (f) Governing Law.  This Agreement shall be governed by and construed in
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     accordance with the laws of the Commonwealth of Massachusetts.

     Executed as of the date first written above.

                             COMPANY:
                               RADIO TELEPHONE SYSTEMS, INC.

                               By:     /s/ George K. Hertz
                                  -----------------------------------------
                               Title: President and Chief Executive Officer
                                  -----------------------------------------
                                
                               INITIAL STOCKHOLDERS:

                                    /s/ Michael J. Buchel
                                    --------------------------------
                                    Michael J. Buchel
                                    Voice Systems Technology Inc.
                                    1874 East Route 20 Suite 8
                                    Cherry Hill, NJ 08003

                               Zuyus Investment Company
                               By: /s/ Peter T. Zuyus, Sr.
                                  ----------------------------------
                                    Peter T. Zuyus, Sr.
                                    Voice Systems Technology, Inc.
                                    621 East Fourth
                                    Tulsa, OK 74120-3017

 
                                    /s/ John M.Freese 
                                    ----------------------------------
                                    John M.Freese
                                    Freese & March, P.A.
                                    4310 East 31st Street
                                    Tulsa, Oklahoma 74135

                                    /s/ Peter T. Zuyus, Jr.
                                    ----------------------------------
                                    Peter T. Zuyus, Jr.
                                    Voice Systems Technology Inc.
                                    621 East Fourth
                                    Tulsa, OK 74120-3017

                                    /s/ Joseph Giegerich  
                                    ----------------------------------
                                    Joseph Giegerich
                                    Voice Systems Technology Inc.
                                    1874 East Route 20, Suite 8
                                    Cherry Hill, NJ 08003

                                    /s/ Terrence G. Hare III 
                                    ----------------------------------
                                    Terrence G. Hare III
                                    Voice Systems Technology Inc.
                                    621 East Fourth
                                    Tulsa, OK 74120-3017

                                    /s/ J. Michael Looney   
                                    ----------------------------------
                                    J. Michael Looney
                                    Voice Systems Technology Inc.
                                    621 East Fourth
                                    Tulsa, OK 74120-3017