Document:

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                                                                     EXHIBIT 4.1

                               SECURITY AGREEMENT

                           DATED AS OF JANUARY 3, 2001

                                  BY AND AMONG

                       SONUS COMMUNICATION HOLDINGS, INC.

                       EMPIRE ONE TELECOMMUNICATIONS, INC.

                                       AND

                            QUADRANT MANAGEMENT, INC.

<PAGE>   2

                               SECURITY AGREEMENT

        This SECURITY AGREEMENT (as amended, supplemented or modified from time
to time, this "Security Agreement") is dated as of January 3, 2001 and is by and
among SONUS COMMUNICATION HOLDINGS, INC., a Delaware corporation (the
"Company"), EMPIRE ONE TELECOMMUNICATIONS, INC., a Delaware corporation and
wholly owned subsidiary of the Company (the "Guarantor") and QUADRANT
MANAGEMENT, INC. (the "Lender").

                                    RECITALS

        WHEREAS, the Lender has determined to loan the Company EIGHTY THOUSAND
DOLLARS ($80,000) (the "Loan") to finance the working capital requirements of
the Company as evidenced by that certain 15% Secured Subordinated Convertible
Debenture (the "Debenture") dated of even date herewith executed by the Company
and guaranteed by the Guarantor;

        WHEREAS, as a condition of the Loan, the Lender has requested the
Guarantor to guarantee the obligations of the Company to the Lender in
connection with the Loan; and

        WHEREAS, in order to secure the Company's obligations under the
Debenture and the Guarantor's obligations pursuant to its guarantee of the
Debenture, the Lender has requested that the Company and the Guarantor enter
into this Security Agreement.

        NOW, THEREFORE, for One Dollar ($1.00) and other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged, the
parties hereto agree as follows:

                                   ARTICLE 1.
                                   DEFINITIONS

     SECTION 1.1. DEFINITIONS. Capitalized terms used herein but not defined
herein, but which are defined in the Loan Documents, have for the purposes
hereof the meanings set forth in the Loan Documents, and the following terms, as
used herein, have the following meanings:

        "Collateral" has the meaning set forth in Section 2.1.

        "Loan Documents" means this Agreement and the Debenture.

        "Liens" means any statutory or common law consensual or non-consensual
mortgage, pledge, security interest, encumbrance, lien, right of setoff, claim
or charge of any kind, including, without limitation, any conditional sale or
other title retention transaction, any lease transaction in the nature thereof
and any secured transaction under the UCC of any jurisdiction.

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        "Obligations" means the present and future duties, covenants and
responsibilities due to Lender by the Company and the Guarantor under the
Debenture and guaranty thereof.

        "Permitted Liens" means (a) Liens held by Lender, (b) Liens for taxes
not delinquent or for taxes being diligently contested in good faith by the
Company or Guarantor by appropriate proceedings, (c) mechanic's, workman's,
materialman's, landlord's carrier's and other like Liens arising in the ordinary
course of business with respect to obligations which are not due or which are
being diligently contested in good faith by the Company or Guarantor by
appropriate proceedings, provided such Liens did not arise in connection with
the borrowing of money or the obtaining of advances or credit and do not, in
Lender's discretion, in the aggregate materially detract from the value of the
Company or Guarantor's respective assets or materially impair the use thereof,
(d) Liens specifically consented by Lender in writing; and (e) Liens set forth
in Schedule 1.1.

        "Receivables" means all accounts now or hereafter owing to the Company
or Guarantor, and all accounts as such term is used in the UCC, accounts
receivable, contract rights, documents, instruments or chattel paper
representing amounts payable or monies due or to become due to the Company or
Guarantor, arising from the sale of inventory or the rendition of services in
the ordinary course of business or otherwise (whether or not earned by
performance), together with all inventory returned by or reclaimed from
customers wherever such inventory is located, and all guaranties, securities and
Liens, except Permitted Liens, held for the payment of any such account, account
receivable, contract right, document, instrument or chattel paper.

        "UCC" means the Uniform Commercial Code as in effect from time to time
in the State of New York; provided, however, that if, by reason of mandatory
provisions of law, the validity or perfection of any security interest granted
to the Lender hereunder is governed by the Uniform Commercial Code as in effect
in a jurisdiction other than New York then, as to the validity or perfection of
such security interest, "UCC" means the Uniform Commercial Code as in effect in
such other jurisdiction.

        SECTION 1.2. UCC DEFINITIONS. The uncapitalized terms "account",
"account receivable", "chattel paper", "contract right", "document", "document
of title", "instrument", "inventory", and "money", as used in Section 1.1 or
elsewhere in this Security Agreement have the respective meanings set forth in
the UCC.

                                   ARTICLE 2.
                               SECURITY INTERESTS

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     SECTION 2.1. GRANT OF SECURITY INTERESTS. As security for the payment and
performance of all of the Obligations, the Company and the Guarantor hereby
assign, pledge and grant to Lender a continuing security interest in their
respective rights, title and interests in and to all Receivables whether now or
hereafter acquired (the "Collateral").

     SECTION 2.2. SALES AND COLLECTIONS.

        a. The Company and the Guarantor are authorized to conduct their
respective businesses and to sell their respective inventory in the ordinary
course of its business for fair value and on an arm's-length basis and to use
and consume any raw materials, supplies and materials in the ordinary course of
their respective businesses.

        b. The Company and the Guarantor are authorized to collect and use for
their benefit proceeds of, and amounts owing to it with respect to, their
respective Collateral, provided no Default shall have occurred and be continuing
with respect to their respective Obligations.

     SECTION 2.3. RELEASE OF COLLATERAL. Lender will promptly, upon payment in
full of the Obligations (and upon notice from the Company or Guarantor but at
the expense of the Company or Guarantor), send the Company and the Guarantor,
for each jurisdiction in which a UCC financing statement is on file to perfect
the security interests granted to Lender hereunder, a termination statement to
the effect that Lender no longer claims a security interest under such financing
statement.

     SECTION 2.4. SUBORDINATION. Lender agrees and acknowledges that the
security interest granted herein shall be subordinate to the Permitted Liens and
any institutional debt financing or receivables financing arrangement entered
into by the Company and/or the Guarantor.

     SECTION 2.5. FINANCING STATEMENTS. The Company and Guarantor hereby agree
to execute and deliver to Lender such UCC-1 Financing Statement(s) in proper
form for filing as Lender may request to perfect the security interests granted
by this Agreement.

                                   ARTICLE 3.
                 REPRESENTATIONS AND WARRANTIES OF THE GUARANTOR

        The Company and the Guarantor represent and warrant that:

     SECTION 3.1. TITLE TO COLLATERAL. Except for the security interests granted
to Lender hereunder, the Company and the Guarantor are the sole owner of their
respective Collateral, having good and marketable title thereto, free and clear
of any and all liens, except the Permitted Liens.

     SECTION 3.2. PLACE OF BUSINESS. Schedule 3.2 correctly sets forth the
Company's and the Guarantor's chief executive office and principal place of
business and the offices where records concerning the Receivables are kept.

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                                   ARTICLE 4.
                                   COVENANTS

        The Company and the Guarantor agree that so long as any Obligation
remains unpaid:

     SECTION 4.1. PLACE OF BUSINESS. The Company and the Guarantor will not
change the location of (i) their respective places of business, (ii) their
respective chief executive office or (iii) the office or other locations where
they keep or hold any records relating to the Collateral from the applicable
location listed on Schedule 3.2 unless, prior to such change, they notify Lender
of such change so that Lender may reasonably request to preserve, perfect,
confirm and protect the security interests granted to Lender hereunder.

     SECTION 4.2. MAINTENANCE OF RECORDS. The Company and the Guarantor will
keep and maintain at its expense complete books and records relating to their
respective Collateral which are satisfactory to Lender including, without
limitation, a record of all payments received and all credits granted with
respect to their respective Collateral.

                                   ARTICLE 5.
                                  MISCELLANEOUS

     SECTION 5.1. NOTICES. All notices, requests and other communications to a
party hereunder shall be in writing and shall be given to such party at its
address set forth on the signature page hereof or such other address as such
party may hereafter specify for that purpose by notice to the other. Each such
notice, request or other communication shall be effective (i) if given by mail,
72 hours after such communication is deposited in the mails with first class
postage prepaid, addressed as aforesaid or (ii) if given by any other means,
when delivered as specified in this Section 5.1.

     SECTION 5.2. NO WAIVERS. No failure or delay by Lender in exercising any
right, power or privilege hereunder shall operate as a waiver thereof, nor shall
any single or partial exercise thereof preclude any other or further exercise
thereof or the exercise of any other right, power or privilege. The rights and
remedies herein provided shall be cumulative and not exclusive of any rights or
remedies provided by law.

     SECTION 5.3. AMENDMENTS AND WAIVERS. Any provision of this Agreement may be
amended or waived if, but only if, such amendment or waiver is in writing and is
signed by the Company, the Guarantor and Lender.

     SECTION 5.4. SUCCESSORS AND ASSIGNS. The provisions of this Security
Agreement shall be binding upon and inure to the benefit of the parties hereto
and their respective successors, heirs and permitted assigns.

     SECTION 5.5. GOVERNING LAW. This Security Agreement shall be governed by
and construed in accordance with the internal laws of the State of New York.

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     SECTION 5.6. COUNTERPARTS; EFFECTIVENESS. This Security Agreement may be
signed in any number of counterparts, each of which shall be an original, with
the same effect as if the signatures thereto and hereto were upon the same
instrument. This Security Agreement shall become effective when Lender shall
have received counterparts hereof signed by both parties.

     SECTION 5.7. AMENDMENTS, SUPPLEMENTS AND WAIVERS. The parties hereto may,
from time to time, enter into written agreements supplemental hereto for the
purpose of adding any provisions to this Security Agreement, waiving any
provisions hereof or changing in any manner the rights of the parties.

     SECTION 5.8. LIMITATION OF LAW; SEVERABILITY.

        a. All rights, remedies and powers provided in this Security Agreement
may be exercised only to the extent that the exercise thereof does not violate
any applicable provision of law, and all the provisions of this Agreement are
intended to be subject to all applicable mandatory provisions of law which may
be controlling and to be limited to the extent necessary so that they will not
render this Security Agreement invalid, unenforceable in whole or in part, or
not entitled to be recorded, registered or filed under the provisions of any
applicable law.

        b. If any provision hereof is invalid and unenforceable in any
jurisdiction, then, to the fullest extent permitted by law, (i) the other
provisions hereof shall remain in full force and effect in such jurisdiction and
shall be liberally construed in order to carry out the intentions of the parties
hereto as nearly as may be possible and (ii) the invalidity or unenforceability
of any provision hereof in any jurisdiction shall not affect the validity or
enforceability of such provisions in any other jurisdiction.

     SECTION 5.9. TERMINATION; SURVIVAL. This Security Agreement shall terminate
when the security interests granted hereunder have terminated and the Collateral
has been released as provided in Section 2.3.

     SECTION 5.10. WAIVER OF JURY TRIAL; SUBMISSION TO JURISDICTION. Any legal
action or proceeding with respect to this Agreement shall be brought in a
federal court or state court in the State of New York, and by execution and
delivery of this Agreement the parties hereto hereby accept for themselves and
in respect of their property, generally and unconditionally, the jurisdiction of
such courts. THE PARTIES HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY
OBJECTION, INCLUDING, WITHOUT LIMITATION, ANY OBJECTION TO THE LAYING OF VENUE
OR BASED ON THE GROUNDS OF FORUM NON CONVENIENS, WHICH IT NOW HAS OR HEREAFTER
MAY HAVE TO THE BRINGING OF ANY ACTION OR PROCEEDING IN SUCH JURISDICTIONS.

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

                            [SIGNATURE PAGE FOLLOWS]

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                                  SONUS COMMUNICATION HOLDINGS,
                                  INC.

                                  By:
                                     ---------------------------
                                  Name:  John K. Friedman
                                  Title: President

                                  Address: 55 John Street, 2nd Floor
                                  New York, New York 10038

                                  EMPIRE ONE TELECOMMUNICATIONS,
                                  INC.

                                  By:
                                     ---------------------------
                                  Name:  John K. Friedman
                                  Title: President

                                  Address: 55 John Street, 2nd Floor
                                  New York, New York 10038

                                  QUADRANT MANAGEMENT, INC.

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

                                  Address: 720 Fifth Avenue, 8th Floor
                                  New York, New York 10018

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                                  Schedule 1.1

                                 Permitted Liens

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                                  Schedule 3.2

Company's Chief Executive Office
  and Principal Places of Business

55 John Street, 2nd Floor
New York, New York  10038

The Guarantor's Chief Executive Office
  and Principal Places of Business

55 John Street, 2nd Floor
New York, New York  10038

Location of Records of Receivables

55 John Street, 2nd Floor
New York, New York  10038<PAGE>   1
                                                                     EXHIBIT 4.2

THIS DEBENTURE AND THE SHARES OF COMMON STOCK OF SONUS COMMUNICATION HOLDINGS,
INC., A DELAWARE CORPORATION (THE "BORROWER") INTO WHICH THIS DEBENTURE MAY
BECOME CONVERTIBLE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR
ANY STATE SECURITIES LAW, AND MAY NOT BE SOLD OR OFFERED FOR SALE IN THE ABSENCE
OF AN EFFECTIVE REGISTRATION STATEMENT AS TO THE SECURITIES UNDER SAID ACT AND
ANY APPLICABLE STATE SECURITIES LAW OR AN OPINION OF COUNSEL SATISFACTORY TO THE
BORROWER THAT SUCH REGISTRATION IS NOT REQUIRED.

                       SONUS COMMUNICATION HOLDINGS, INC.

                 15% SECURED SUBORDINATED CONVERTIBLE DEBENTURE

                                                   January 3, 2001
                                                   New York, New York

$80,000

        FOR VALUE RECEIVED, SONUS COMMUNICATION HOLDINGS, INC., a Delaware
corporation ("Borrower"), hereby promises to pay to the order of QUADRANT
MANAGEMENT, INC., with an address at 720 Fifth Avenue, 8th Floor, New York, New
York 10018 ("Lender") the principal sum of Eighty Thousand Dollars ($80,000),
together with interest accrued thereon at an interest rate equal to fifteen
percent (15%) per annum on the date (the "Maturity Date") that is the earlier of
(i) ninety (90) days from the date first set forth above; (ii) the date of
closing of the funding of the $500,000 subordinated convertible debenture to be
provided by the Lender pursuant to the letter from lender to Borrower dated
December 21, 2000; or (iii) upon the closing of any other financing in excess of
$200,000. Anything to the contrary herein notwithstanding, no payment of
principal or interest shall be required to be made by Borrower to the extent
such principal or interest is converted into shares of common stock of the
Borrower (the "Common Stock") as provided herein.

        The obligations of Borrower hereunder are guaranteed by EMPIRE ONE
TELECOMMUNICATIONS, INC., a Delaware corporation and wholly owned subsidiary of
Borrower ("Guarantor"). The obligations of Borrower and Guarantor hereunder
shall be secured by a security interest granted in certain assets of the
Borrower and Guarantor as provided in that certain Security Agreement (the
"Security Agreement") by and among the Borrower, Guarantor and Lender dated of
even date herewith. Lender agrees and acknowledges that the security interest
granted therein shall be subordinated to the Permitted Liens (within the meaning
of the Security Agreement) and otherwise as provided in the Security Agreement.

        Notwithstanding any other provision hereof, interest paid or becoming
due hereunder shall in

<PAGE>   2

no event exceed the maximum rate permitted by applicable law. Both principal and
interest are payable in lawful money of the United States of America to the
Lender at the address above indicated.

        This Debenture and the provisions hereof are to be construed according
to, and are governed by, the laws of the State of Delaware, without regard to
principles of conflicts of laws thereof, and this Debenture is further subject
to the following additional provisions:

        1. Events of Default. (a) If one or more of the following events (herein
called "Events of Default") shall have occurred and be continuing, that is to
say:

                (i) If the Borrower shall default in the payment of the
        principal or interest of this Debenture after the same shall become due
        and payable, and such default shall not have been remedied within thirty
        (30) days after written notice thereof to Borrower; or

               (ii) If the Borrower or any of its subsidiaries shall (1)
        commence any proceeding or other action relating to it in bankruptcy or
        seek reorganization, arrangement, readjustment of its debts,
        dissolution, liquidation, winding-up, composition or any other relief
        under the U.S. Bankruptcy Code, or under any other insolvency,
        reorganization, liquidation, dissolution, arrangement, composition,
        readjustment of debt or any other similar act or law, of any
        jurisdiction; or (2) admit the material allegations of any petition or
        pleading in connection with any such proceeding; or (3) apply for, or
        consent or acquiesce to, the appointment of a receiver, conservator,
        trustee or similar officer for it or for all or a substantial part of
        its property; or (4) make a general assignment for the benefit of
        creditors; or (5) have any of the foregoing proceedings commenced
        against it by a third party and such proceeding or proceedings are not
        vacated within ninety (90) days;

then the holder of this Debenture may, at any time thereafter, at its option by
written notice to the Borrower, declare the principal and all accrued interest
thereon to be immediately due and payable, and thereupon the same shall become
so due and payable.

               (b) Non-Waiver and Other Remedies. No course of dealing or delay
on the part of Lender in exercising any right hereunder shall operate as a
waiver thereof or otherwise prejudice the right of any holder. No remedy
conferred hereby shall be exclusive of any other remedy referred to herein or
now or hereafter available at law, in equity, by statute or otherwise. In case
of any Event of Default, Borrower will reimburse the Lender for its reasonable
attorneys' fees incurred in connection with the enforcement of its rights
hereunder.

        2. Conversion Feature; Mechanics of Conversion or Cash Payment.

               (a) At any time on or prior to the Maturity Date, the Lender may,
at its option, convert all or such portion of outstanding principal and accrued
but unpaid interest hereon (the "Outstanding Amount") as Lender may designate in
writing, into such number of shares of Borrower's Common Stock (the "Conversion
Shares") as is equal to the quotient obtained by dividing (A) the Outstanding
Amount, or in the case of a partial conversion of this Debenture, such

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portion of the Outstanding Amount as Lender may specify in writing to Borrower,
by (B) Five Cent ($.05) (the "Conversion Price"), rounded to the nearest whole
share, by providing the Borrower with written notice thereof (the "Conversion
Notice"). Accrued interest hereon shall be converted prior to conversion of any
outstanding principal.

               (b) Mechanics and Effect of Conversion. No fractional shares of
the Borrower's Common Stock will be issued upon conversion of this Debenture. In
lieu of any fractional share to which the Lender would otherwise be entitled,
the Borrower will pay to Lender in cash the amount of the unconverted portion of
this Debenture that would otherwise be converted into such fractional shares.
Upon conversion of this Debenture, Lender shall surrender this Debenture, duly
endorsed, at the principal offices of the Borrower or any transfer agent of the
Borrower. At its expense, the Borrower will, as soon as practicable thereafter,
issue and deliver to Lender a certificate or certificates for the number of
shares of Common Stock to which Lender is entitled upon such conversion,
together with such other securities and property to which Lender is entitled
upon such conversion under the terms of this Debenture, including a check
payable to Lender for any cash amounts payable as described herein. Upon
conversion of this Debenture, the Borrower will be forever released from all of
its obligations and liabilities under this Debenture, including without
limitation the obligation to pay the principal and interest due and payable
under this Debenture.

               (c) Mechanics of Cash Payment. Upon request for payment of this
Debenture at any time after the Maturity Date, Lender shall surrender this
Debenture, duly endorsed, at the principal offices of the Borrower. At its
expense, the Borrower will, as soon as practicable thereafter, make a cash
payment in lawful money of the United States of the principal and interest due
and payable under this Debenture. Upon request for payment and satisfaction
thereof, the Borrower shall be forever released from all of its obligations and
liabilities under this Debenture, including without limitation any conversion
rights otherwise applicable under this Debenture.

               (d) Adjustment for Merger or Reorganization, Etc. In case of any
consolidation or merger of the Borrower with or into another corporation, or the
conveyance of all or substantially all of the assets of the Borrower to another
corporation, or upon a stock split, stock dividend, consolidation or like event,
this Debenture shall thereafter be convertible into the number of shares of
stock or other securities or property to which a holder of the same number of
shares of Common Stock deliverable upon conversion of this Debenture would have
been entitled upon such event; and, in any such case, appropriate adjustment
shall be made to the Conversion Price, as is appropriate for the circumstances,
to the extent that the provisions set forth herein shall be thereafter
applicable in relation to any shares of stock or other property thereafter
deliverable upon the conversion of the Debenture.

               (e) Certificate as to Adjustments. Upon the occurrence of each
adjustment or readjustment of the Conversion Price, the Borrower at its expense
promptly shall compute such adjustment or readjustment and furnish to the holder
of this Debenture a certificate setting forth such adjustment or readjustment
and showing in detail the facts upon which such adjustment or readjustment is
based, which shall be conclusive absent manifest error.

               (f) Further Adjustments. In case at any time conditions arise
which in the opinion of

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the Board of Directors or in the opinion of the Lender, are not adequately
covered by the provisions of this Section 2, or which might materially and
adversely affect the rights of the Lender in connection with the conversion of
the Debentures, then the Board of Directors shall appoint a firm of independent
certified public accountants of recognized national or regional standing, who
shall give their opinion upon the adjustment, if any, necessary with respect to
the Conversion Price, so as to preserve the conversion rights of the Lender.
Upon receipt of such opinion, the Board of Directors forthwith shall make the
adjustments described therein.

        3. Representations and Warranties of Lender. Lender hereby represents
and warrants to Borrower as follows:

               a. Purchase Entirely for Own Account, Etc.. The Conversion Shares
to be acquired by Lender hereunder upon conversion of this Debenture will be
acquired for investment for Lender's own account, not as a nominee or agent, and
not with a view to the resale or distribution of any part thereof. Lender has no
present intention of selling, granting any participation in, or otherwise
distributing this Debenture or the Conversion Shares. Lender does not have any
contract, undertaking, agreement or arrangement with any person to sell,
transfer or grant participations to any person with respect to this Debenture or
the Conversion Shares. The Lender has not construed the contents of this
Debenture, or any additional agreement with respect to the proposed investment
in the Shares or any prior or subsequent communications from Borrower, or any of
its officers, employees or representatives, as investment, tax or legal advice,
or as information necessarily applicable to such Lender's particular financial
situation. The Lender has consulted its own financial advisor, tax advisor,
legal counsel and accountant, as necessary or desirable, as to matters
concerning his investment in the Conversion Shares.

               b. Disclosure. Lender has received or reviewed all the
information which such Lender has requested for the purposes of determining the
merits of the Conversion Shares as an investment. Lender has also received and
reviewed a copy of the Company's audited financial statements for the period
ended September 30, 2000 and other filings made with the Securities Exchange
Commission (the "Commission"). Lender has had an opportunity to ask questions
and receive answers from the Borrower regarding the Borrower, its business, and
the terms and conditions of the conversion of this Debenture and the Conversion
Shares. LENDER ACKNOWLEDGES AND AGREES THAT THE CONVERSION OF THE DEBENTURE
INVOLVES A HIGH DEGREE OF RISK, AND MAY RESULT IN A LOSS OF THE ENTIRE AMOUNT
CONVERTED. THERE IS NO ASSURANCE THAT THE BORROWER'S OPERATIONS WILL BE
PROFITABLE IN THE FUTURE OR THAT ANY PUBLIC MARKET FOR THE SHARES WILL BE
AVAILABLE.

               c. Accredited Lender. Lender is, as of the date hereof and as of
the date all or any portion of this Debenture is converted into Conversion
Shares, an accredited Lender as defined in Rule 501(a) of Regulation D under the
Securities Act of 1933, as amended ("Securities Act"). Lender is capable of
bearing the economic risk of an investment in the Conversion Shares, including
the possible loss of Lender's entire investment. Lender has such knowledge and
experience in financial or business matters that it is capable of evaluating the
merits and risks of an investment in the Conversion Shares offered hereby. If
other than an individual, Lender has not been organized

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solely for the purpose of acquiring the Conversion Shares.

               d. Restricted Securities. Lender understands that the Conversion
Shares are "restricted securities" as defined in the Securities Act, and that
under federal and state securities laws the Conversion Shares may be resold
without registration under the Securities Act only in certain limited
circumstances. Lender is familiar with Rule 144 promulgated by the Commission
under the Securities Act, and understands the resale limitations imposed thereby
and by the Securities Act generally. Lender also acknowledges that the Shares
are subject to significant restrictions on transfer, pledge or hypothecation.

               e. Legends. It is understood that certificates or other evidence
of the Conversion Shares may bear the following legend, as well as any legend
required by the laws of any state:

               "THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
               ACT OF 1933, AS AMENDED. THEY MAY NOT BE SOLD, OFFERED FOR SALE,
               PLEDGED OR HYPOTHECATED IN THE ABSENCE OF A REGISTRATION
               STATEMENT IN EFFECT WITH RESPECT TO THE SECURITIES UNDER SUCH ACT
               OR AN OPINION OF COUNSEL SATISFACTORY TO THE ISSUER THAT SUCH
               REGISTRATION IS NOT REQUIRED PURSUANT TO A VALID EXEMPTION
               THEREFROM UNDER THE SECURITIES ACT OF 1933, AS AMENDED."

               4. Covenants of Lender.  Lender hereby covenants with Borrower
that Lender shall not make any disposition of all or any portion of the
Conversion Shares unless and until:

                      a. There is then in effect a registration statement under
the Securities Act covering such proposed disposition, and such disposition is
made in accordance with such registration statement; or

                      b. Such Lender shall have notified Borrower of the
proposed disposition and shall have furnished Borrower with a detailed statement
of the circumstances surrounding the proposed disposition, and, if requested by
Borrower, Lender shall have furnished Borrower with an opinion of counsel, in
form and substance satisfactory to Borrower, that such disposition will not
require registration of the Conversion Shares under the Securities Act.

               5. Covenants of Borrower.  The Borrower covenants and agrees that
for so long as this Debenture shall remain outstanding the Borrower:

                      a. will cause to be reserved and kept available out of
its authorized and unissued shares of Common Stock such number of shares that
will be sufficient to permit the conversion in full of all outstanding
Debentures;

                      b. will take all such action as may be necessary to ensure
that all shares of Common Stock delivered upon conversion of the Debentures
shall, at the time of delivery of the certificates for such shares, be duly and
validly authorized, issued, fully paid and non-assessable;

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                      c. will duly and punctually pay, or cause to be paid, the
principal and interest on this Debenture on the date(s) on which such principal
and interest comes due and payable in accordance with the terms hereof;

                      d. will preserve and keep in full force and effect its
corporate existence;

                      e  will not declare or pay any cash dividend or other
distribution on the Common Stock or make, or directly or indirectly assume, any
liability or obligation in connection with any distribution of any sort in
respect to its Common Stock.

                                            SONUS COMMUNICATION HOLDINGS, INC.

                                            By:
                                                 John K. Friedman, President

        FOR VALUE RECEIVED, Empire One Telecommunications, Inc., a Delaware
corporation and wholly owned subsidiary of Borrower ("EOT") guarantees to the
Lender hereunder the punctual payment of the principal and interest due and
payable under this Debenture at the time and in the manner specified in this
Debenture and according to the terms and conditions specified herein; provided,
however, that EOT does not and cannot guarantee any request for conversion of
the principal and interest hereunder into the Common Stock of the Borrower.

        IN WITNESS WHEREOF, EOT has caused its corporate name to be attached
hereto by its president.

                                            EMPIRE ONE TELECOMMUNICATIONS, INC.

                                            By:
                                              --------------------------------
                                                 John K. Friedman, President

AGREED TO AND ACCEPTED BY:
QUADRANT MANAGEMENT, INC.

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

                                       6

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00026-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00026-of-00352.parquet"}]]