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                                                                     EXHIBIT 4.5

                         REGISTRATION RIGHTS AGREEMENT


       This REGISTRATION RIGHTS AGREEMENT (this "Agreement"), is dated as of
________________ __, 200__, by and between SONUS COMMUNICATION HOLDINGS, INC., a
Delaware corporation (the "COMPANY"), the Principal Stockholders (within the
meaning of the Merger Agreement defined below), and the stockholders of Empire
One Telecommunications, Inc., a New York corporation, who agree to be bound by
this Agreement listed on Schedule A attached hereto and incorporated by
reference herein (each a "STOCKHOLDER" and collectively, the "STOCKHOLDERS").

       WHEREAS, pursuant to the terms of that certain Merger Agreement of even
date herewith by and between the Company, EOT Acquisition Corporation, a
Delaware corporation ("Acquisition"), Empire One Telecommunications, Inc., a New
York corporation ("Empire One"), the Stockholder and certain other stockholders
of Empire One (the "MERGER AGREEMENT"), the Stockholder will receive, pursuant
to the conditions of the Merger Agreement, _________ shares of the Company's
Common Stock, par value $.0001 per share (the "COMMON STOCK") upon the
consummation of the merger of Empire One into Acquisition (the "Merger"); and

       WHEREAS, in order to induce the Stockholder to enter into the Merger
Agreement and/or vote for the Merger contemplated thereby, the Company desires
to grant registration rights to the Stockholder for the shares of Common Stock
to be received in the Merger in accordance with the terms and conditions hereof;

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

       1. DEFINITIONS. As used herein the following defined terms shall have the
following respective meanings:

              (a) "CAPITAL STOCK" means the Company's Common Stock and any other
       class of common stock created by the Company in the future.

              (b) "COMMON STOCK" has the meaning set forth in the Recitals.

              (c) "HOLDERS" means any person or entity to whom shares of Capital
       Stock were issued pursuant to the Merger Agreement and which agrees to be
       bound by this Agreement.

              (d) "INDEMNIFIED PARTY" has the meaning set forth in subparagraph
       6(c).

              (e) "INDEMNIFYING PARTY" has the meaning set forth in subparagraph
       6(c).


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              (f) The terms "REGISTER," "REGISTERED" and "REGISTRATION" refer to
       a registration effected by preparing and filing a registration statement
       in compliance with the Securities Act.

              (g) "REGISTRABLE SECURITIES" means all shares of Capital Stock of
       the Company issued pursuant to the Merger Agreement.

              (h) "SEC" means the Securities and Exchange Commission.

              (i) "SECURITIES ACT" means the Securities Act of 1933, as amended.


       2. RESERVED.

       3. COMPANY REGISTRATION.

              (a) If the Company, at any time after the completion of the next
       registration of Capital Stock under the Securities Act to occur following
       the date hereof, shall determine to register any of its securities,
       either for its own account or the account of a security holder or
       holders, in a registration statement covering the sale of Capital Stock
       to the general public pursuant to an underwritten public offering (except
       with respect to any registration filed on Form S-8, Form S-4 or any
       successor forms thereto), the Company will: (i) give to each Holder
       written notice thereof at least 45 days before filing; provided, however,
       in the case of a Registration Statement on Form S-3, the Company shall be
       required to give each Holder written notice of the proposed filing
       thereof promptly after a decision to make such filing has been made and
       in no event less than ten business days prior to filing; and (ii) use its
       best efforts to include in such registration (and any related
       qualification under blue sky laws) and in any underwriting involved
       therein, all the Registrable Securities specified in a written request or
       requests, made within 15 days after receipt of such written notice from
       the Company, or, in the case of a Registration Statement on Form S-3,
       within seven business days after receipt of such written notice, by any
       Holder or Holders, except as set forth in subparagraph 3(b) below. The
       notice referred to in this subparagraph shall include a list of the
       jurisdictions in which the Company intends to attempt to qualify such
       securities under the applicable blue sky or other state securities laws.

              (b) The right of any Holder to registration pursuant to this
       Paragraph 3 shall be conditioned upon such Holder's participation in the
       underwriting to the extent provided herein. All Holders proposing to
       distribute their securities through such underwriting shall (together
       with the Company) enter into an underwriting agreement in customary form
       with the underwriter or underwriters selected for such underwriting by
       the Company, and may, at their option, require that any or all the
       representations and warranties by, and the covenants and other agreements
       on the part of, the Company to and for the benefit of such underwriter
       shall also be made to and for the benefit of such Holders. Such Holders
       shall not be required to make any representations or warranties to or
       agreements with the Company or the underwriter other than those relating
       to such Holders, their Registrable Securities and their intended methods
       of distribution and information about such Holders provided by such



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       Holders for use in the registration statement. Upon the written request
       of the managing underwriter of any underwritten offering of the Company's
       securities, a Holder of Registrable Securities shall not sell, make any
       short sale of, loan, grant any option for the purchase of, or otherwise
       dispose of any Registrable Securities (other than those included in such
       registration) without the prior written consent of such managing
       underwriter for a period (not to exceed 30 days before the effective date
       and 75 days thereafter) that such managing underwriter reasonably
       determines is necessary in order to effect the underwritten public
       offering. Notwithstanding any other provision of this Paragraph 3, if the
       underwriter determines that marketing factors require a limitation of the
       number of shares to be underwritten, the Company shall so advise all
       Holders of Registrable Securities which would otherwise be registered and
       underwritten pursuant hereto, and the Company shall include in such
       registration first the number of shares requested to be sold by the
       Company together with the number of shares requested to be sold by the
       persons and entities exercising demand registration rights with respect
       to such registration, if any, then the number of shares of Registrable
       Securities requested to be included in the registration which, in the
       opinion of such underwriter, can be sold, pro rata among all Holders
       thereof and all other shareholders of the Company that have contractual
       rights with respect to the registration of shares of Capital Stock held
       by such shareholders (the "Other Holders") in proportion, as nearly as
       practicable, to the respective amounts of Registrable Securities held by
       such Holders and Other Holders at the time of filing the registration
       statement, with further proportional allocations among the Holders and
       Other Holders if any such Holder or Other Holder has requested less than
       all such Registrable Securities it is entitled to register.

       4. EXPENSES OF REGISTRATION. All expenses incurred in connection with any
       registration or qualification pursuant to this Agreement, including,
       without limitation, all registration, filing and qualification fees,
       printing expenses, fees and disbursements of counsel for the Company, and
       expenses and fees of any special audits incidental to or required by such
       registration, shall be borne by the Company; provided, however, that the
       Company shall not be required to pay fees of legal counsel of the
       Holders, or underwriters' discounts or commissions relating to
       Registrable Securities (such underwriters' fees, discounts or commissions
       to be borne by the Holders, on a pro rata basis, based on the number of
       shares of Registrable Securities sold by each of them).

       5. REGISTRATION PROCEDURES. In the case of each registration effected by
       the Company pursuant to this Agreement, the Company will keep each Holder
       participating therein advised in writing as to the initiation of such
       registration (and any state qualifications) and as to the completion
       thereof. The Company may decline to file a Registration Statement after
       giving notice to each Holder, or withdraw any registration after filing
       and after such notice, but prior to the effectiveness thereof, provided
       that the Company shall promptly notify each Holder in writing of any such
       action and provided further that the Company shall bear all expenses
       incurred by such Holder or otherwise in connection with such withdrawn
       registration. Upon receipt of written notice from the Company that a
       registration statement or prospectus contains a Misstatement (as defined
       below), each Holder of Registrable Securities shall forthwith discontinue
       disposition of Registrable Securities until such Holder has received
       copies of the supplemented or amended prospectus, or until such Holder is
       advised in writing by the Company that the use of the



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       prospectus may be resumed, and, if so directed by the Company, such
       Holder shall deliver to the Company (at the Company's expense) all
       copies, other than permanent file copies then in such Holder's
       possession, of the prospectus covering such Registrable Securities
       current at the time of receipt of such notice.

       6. INDEMNIFICATION.

              (a) The Company will indemnify each Holder of Registrable
       Securities, each of the Holder's officers, directors, partners and
       employees, and each person controlling such Holder, with respect to such
       registration or qualification effected pursuant to this Agreement and in
       which Registrable Securities of the Holders are included, against all
       claims, losses, damages, and liabilities (or actions in respect thereto)
       arising out of or based on any untrue statement (or alleged untrue
       statement) of a material fact contained in any prospectus, registration
       statement or other document incident to any such registration or
       qualification, or based on any omission (or alleged omission) to state
       therein a material fact required to be stated therein or necessary to
       make the statements therein not misleading, or any violation by the
       Company of any rule or regulation promulgated pursuant to any Federal,
       state or common law rule or regulation including, without limitation, the
       Securities Act, applicable to the Company and relating to action or
       inaction required of the Company in connection with any such
       registration, qualification or compliance and will reimburse each such
       Holder, each of the Holder's officers, directors, partners and employees,
       and each person controlling such Holder, for any legal and any other
       reasonable expenses incurred in connection with investigating or
       defending any such claim, loss, damage, liability or action, including
       reasonable attorneys' fees and expenses; provided, however, that the
       Company will not be liable in any such case to the extent that any such
       claim, loss, damage or liability arises out of or is based on any untrue
       statement or omission based upon and in conformity with written
       information furnished to the Company by such Holder. Such indemnity shall
       be effective notwithstanding any investigation made by or on behalf of
       any Holder or any such officer, director, partner, employee, or
       controlling person and shall survive any transfer by the same of the
       Registrable Securities. The foregoing notwithstanding, the Company shall
       not be liable to the extent that any such claim, loss, damage or
       liability arises out of or is based upon an untrue statement of a
       material fact or an omission to state a material fact required to be
       stated in a registration statement or prospectus or necessary to make the
       statements in a registration statement, prospectus or preliminary
       prospectus not misleading (a "Misstatement") or alleged Misstatement made
       in any preliminary prospectus if (i) such Holder failed to send or
       deliver a copy of the Prospectus with or prior to the delivery of written
       confirmation of the sale of Registrable Securities giving rise to such
       claim, loss, damage or liability and (ii) the prospectus would have
       corrected such Misstatement. In addition, the Company shall not be liable
       to the extent that any such claim, loss, damage or liability arises out
       of or is based upon a Misstatement or alleged Misstatement in a
       prospectus, (i) if such Misstatement or alleged Misstatement is corrected
       in an amendment or supplement to such prospectus and (ii) having
       previously been furnished by or on behalf of the Company with copies of
       the prospectus as so amended or supplemented, such Holder thereafter
       fails to deliver such prospectus as so amended or supplemented prior to
       or concurrently with the sale to the person who



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       purchased a Registrable Security from such Holder and who is asserting
       such claim, loss, damage or liability.

              (b) Each Holder will, if Registrable Securities held by or
       issuable to such Holder are included in the securities as to which such
       registration or qualification is being effected, indemnify the Company,
       each of its directors, officers and employees, each person who controls
       the Company, and each other such Holder, each of such other Holder's
       officers, directors, partners and employees, and each person controlling
       such other Holder, against all claims, losses, damages and liabilities
       (or actions in respect thereto) arising out of or based on any untrue
       statement (or alleged untrue statement) of a material fact contained in
       any such registration statement, prospectus or other document, or any
       omission (or alleged omission) to state therein a material fact required
       to be stated therein or necessary to make the statements therein not
       misleading, and will reimburse the Company, such Holders, such directors,
       officers, partners, employees or persons for any legal or any other
       reasonable expenses incurred in connection with investigating or
       defending any such claim, loss, damage, liability or action, including
       reasonable attorneys' fees and expenses, in each case to the extent, but
       only to the extent, that such untrue statement (or alleged untrue
       statement) or omission (or alleged omission) is made in such registration
       statement, prospectus or other document in reliance upon and in
       conformity with written information furnished to the Company by such
       Holder. Notwithstanding the foregoing, the liability of any such Holder
       shall not exceed an amount equal to the proceeds realized by each such
       Holder of Registrable Securities sold as contemplated herein. Such
       indemnity shall be effective notwithstanding any investigation made by or
       on behalf of the Company, any such director, officer, partner, employee,
       or controlling person and shall survive the transfer of such securities
       by such Holder.

              (c) Each party entitled to indemnification under this Paragraph 6
       (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. Unless in the reasonable judgment of the Indemnified Party
       a conflict of interest may exist between the Indemnifying Party and the
       Indemnified Party, the Indemnifying Party shall be permitted to assume
       the defense of any such claim or any litigation resulting therefrom;
       provided, however, that in any event counsel for the Indemnifying Party
       or Indemnified Party who shall conduct the defense of such claim or
       litigation as provided above shall be approved by the other Party (which
       approval shall not be unreasonably withheld), and such other Party may
       participate in such defense at such Party's expense; provided, further,
       that the failure of any Indemnified Party to give notice as provided
       herein shall not relieve the Indemnifying Party of its obligations under
       this Paragraph 6 unless such failure shall have had a material adverse
       effect on the Indemnifying Party's ability to defend such claim.

              (d) The Indemnified Party shall make no settlement of any claim or
       litigation which would give rise to liability on the part of the
       Indemnifying Party under any indemnity contained in this Paragraph 6
       without the written consent of the Indemnifying Party, which consent
       shall not be unreasonably withheld or delayed, and no Indemnifying Party
       shall make any settlement of any such claim or litigation without the
       consent of the Indemnified



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       Party, which consent shall not be unreasonably withheld or delayed. If a
       firm offer is made to settle a claim or litigation defended by the
       Indemnified Party and the Indemnified Party notifies the Indemnifying
       Party in writing that the Indemnified Party desires to accept and agree
       to such offer, but the Indemnifying Party elects not to accept or agree
       to such offer within ten days after receipt of written notice from the
       Indemnified Party of the terms of such offer, then, in such event, the
       Indemnified Party shall continue to contest or defend such claim or
       litigation and, if such claim or litigation is within the scope of the
       Indemnifying Party's indemnity contained in this Paragraph 6, the
       Indemnified Party shall be indemnified pursuant to the terms hereof. If a
       firm offer is made to settle a claim or litigation defended by the
       Indemnifying Party and the Indemnifying Party notifies the Indemnified
       Party in writing that the Indemnifying Party desires to accept and agree
       to such offer, but the Indemnified Party elects not to accept or agree to
       such offer within ten days after receipt of written notice from the
       Indemnifying Party of the terms of such offer, then, in such event, the
       Indemnified Party may continue to contest or defend such claim or
       litigation and, in such event, the total maximum liability of the
       Indemnifying Party to indemnify or otherwise reimburse the Indemnified
       Party in accordance with this Agreement with respect to such claim or
       litigation shall be limited to and shall not exceed the amount of such
       settlement offer, plus reasonable out-of-pocket costs and expenses
       (including reasonable fees and disbursements of counsel) to the date of
       notice that the Indemnifying Party desired to accept such settlement
       offer.

              (e) The indemnification payments required pursuant to this
       Paragraph 6 for expenses of the investigation or defense of a claim or
       lawsuit shall be made from time to time during the course of the
       investigation or defense, as the case may be, upon submission of
       reasonably sufficient documentation that any such expenses have been
       incurred.

       7. INFORMATION BY HOLDER. The Holder or Holders of Registrable Securities
       included in any registration shall furnish to the Company such written
       information regarding such Holder or Holders and the distribution
       proposed by such Holder or Holders as the Company may reasonably request
       in writing and as shall be required in connection with any registration
       or qualification referred to in this Agreement. The Company agrees to
       include in any such registration statement all information concerning the
       Holders and their distribution which the Holders shall reasonably
       request.

       8. CHANGES; WAIVER; ASSIGNMENT. The terms and provisions of this
       Agreement may not be modified, amended or assigned, except that they may
       be modified, amended or assigned with the written consent of (i) the
       Company and (ii) the Holders of a majority of the Registrable Securities
       outstanding. None of the terms and provisions of this Agreement may be
       waived except in writing by the person so waiving.

       9. GOVERNING LAW. This Agreement shall be governed by and construed in
       accordance with the domestic laws of the State of Delaware, without
       giving effect to any choice of law or conflict of law provision or rule
       (whether of the State of Delaware or any other jurisdiction) that would
       cause the application of the laws of any jurisdiction other than the
       State of Delaware.

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       10. NOTICE. All notices, requests and other communications hereunder must
       be in writing and will be deemed to have been duly given only if
       delivered personally against written receipt or by facsimile transmission
       or mailed by prepaid first class certified mail, return receipt
       requested, or delivered by a nationally recognized overnight courier
       service prepaid, to the parties at the following addresses or facsimile
       numbers: If to the Company, to:

                    Sonus Communication Holdings, Inc.
                    1600 Wilson Boulevard, Suite 1008
                    Arlington, Virginia 22209
                    Attention: Rick D. Rose
                    Telecopier: 703-527-8865

                    with a copy to:

                    Cecil E. Martin, III, Esquire
                    McGuire, Woods, Battle & Boothe LLP
                    7 St. Paul Street, Suite 1000
                    Baltimore, Maryland 21202
                    Telecopier:  410-659-4535

       If to the Holders, to the address listed as the most recent address of
       such Holders on the books and records of Empire One Telecommunications,
       Inc.

                   with a copy to:

                   David E. Bronston, Esquire
                   Wolf, Block, Schorr and Solis-Cohen LLP
                   250 Park Avenue
                   New York, New York 10177
                   Telecopier:  212-986-0604

       All such notices, requests and other communications will (i) if delivered
       personally to the address as provided in this Section, be deemed given
       upon delivery, (ii) if delivered by facsimile transmission to the
       facsimile number as provided for in this Section, be deemed given upon
       receipt, (iii) if delivered by mail in the manner described above to the
       address as provided in this Section, be deemed given on the earlier of
       the fourth Business Day following mailing or upon receipt and (iv) if
       delivered by overnight courier to the address as provided for in this
       Section, be deemed given on the earlier of the first Business Day
       following the date sent by such overnight courier or upon receipt (in
       each case regardless of whether such notice, request or other
       communication is received by any other Person to whom a copy of such
       notice is to be delivered pursuant to this Section). Any party from time
       to time may change its address, facsimile number or other information for
       the purpose of notices to that party by giving notice specifying such
       change to the other parties hereto.



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       11. TERMINATION. This Agreement shall terminate with respect to any
       Holder on the date on which the Holder may sell all of such Holder's
       Registrable Securities pursuant to Rule 144 under the Securities Act
       within any 90 day period or, with respect to any such Holder, on the date
       on which all of such Holder's Registrable Securities have been registered
       pursuant to a registration statement filed with the Commission and which
       has become effective.

       12. Arbitration.

              (a) Any controversy or claim arising out of or relating to this
       Agreement, or the breach thereof, shall be settled by arbitration in
       accordance with the Commercial Arbitration Rules of the American
       Arbitration Association by an arbitration panel consisting of three
       persons, one selected by Sonus, one selected by the Principal
       Stockholders and the third selected by mutual agreement of the first two
       arbitrators selected, and judgement upon the award rendered by the
       arbitrators may be entered in any court having jurisdiction thereof.

              (b) The arbitration shall be held in Washington, D.C. if brought
       by Target or any of the Principal Stockholders and in New York City if
       brought by Acquisition or Sonus.

              (c) All fees, costs and expenses (including reasonable attorneys'
       fees and expenses) incurred by a party that prevails on any issue in any
       arbitration commenced hereunder or in any judicial proceeding seeking to
       enforce this Agreement to arbitrate disputes or seeking to enforce any
       order or award of any arbitration hereunder shall be assessed against the
       party or parties that do not prevail on such issue or issues.

       14. COUNTERPARTS. This Agreement may be executed in counterparts, each of
       which shall be deemed an original and which together shall constitute a
       single agreement. This Agreement may be delivered by facsimile.

       15. HEADINGS. The headings of the Paragraphs of this Agreement are
       inserted for convenience only and shall not be deemed to constitute a
       part hereof.

       16. SEVERABILITY. If any provision or any portion of any provision of
       this Agreement shall be held to be void or unenforceable, the remaining
       portions of this Agreement shall continue in full force and effect.

       IN WITNESS WHEREOF, the undersigned have caused this Agreement to be
duly executed by their authorized officers as of the day and year first above
written.

                                         SONUS COMMUNICATION HOLDINGS, INC.



                                         By:  /s/  W. Todd Coffin
                                            ------------------------------------
                                             Name:   W. Todd Coffin
                                             Title:  CEO



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                                         [NAME OF HOLDER]

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



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