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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.





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

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

              (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 prospectus may be resumed, and, if so
       directed by the Company, such



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       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
       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

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       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 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


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       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.

       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:
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                       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.

       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


                                         [NAME OF HOLDER]

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

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