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                                                                     EXHIBIT 3.1
                                                                     -----------

                                 FIRST RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                            NEXAR TECHNOLOGIES, INC.


     Nexar Technologies, Inc., a corporation organized and existing under the
laws of the State of Delaware, hereby certifies as follows:

     1. The name of the corporation is:

        Nexar Technologies, Inc.

     2. The Certificate of Incorporation of the corporation was filed with the
Secretary of State of Delaware on March 7, 1995 under its original name,Tantric
Systems Corp. A Certificate of Amendment was filed with the Secretary of State
of Delaware on March 28, 1995 changing the corporation's name to Dynasys Systems
Corporation. Additional Certificates of Amendment were filed with the Secretary
of State of Delaware on January 22, 1996 and March 28, 1996, the latter of which
changed the name of the corporation to Nexar Technologies, Inc.

     3. This First Restated Certificate of Incorporation integrates and further
amends the Certificate of Incorporation of the corporation, as previously
restated and amended, by amending Articles Second, Fourth, Eighth, Ninth, Tenth
and Eleventh, and by adding Articles Twelfth, Thirteenth, Fourteenth and
Fifteenth, all as set forth in this First Restated Certificate of Incorporation.

     4. This First Restated Certificate of Incorporation was duly proposed and
declared advisable by the Board of Directors of the corporation in accordance
with the applicable provisions of Sections 242 and 245 of the General
Corporation Law of the State of Delaware. The stockholders of the corporation
duly approved this First Restated Certificate of Incorporation without a meeting
by less than unanimous written consent, and prompt notice has been given to
those stockholders who have not consented in writing, all in accordance with
Section 228 of the General Corporation Law of the State of Delaware. The capital
of the corporation has not been reduced by the amendments effected by this First
Restated Certificate of Incorporation.

     5. This First Restated Certificate of Incorporation, as amended and
restated herein, shall upon the effective date hereof, read as follows:

     FIRST: The name of the corporation is:
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              Nexar Technologies, Inc.


     SECOND: The registered office of the corporation in the State of Delaware
is located at 1013 Centre Road, City of Wilmington, County of New Castle and the
name of its registered agent is Corporation Service Company, formerly known as
The Prentice-Hall Corporation System, Inc.

     THIRD:  The  purpose of the  corporation  is to engage in any lawful act or
activity for which  corporations may be organized under the General  Corporation
Law of the State of Delaware.

     FOURTH: The total number of shares of capital stock which the corporation
shall have authority to issue is 40,000,000, of which 30,000,000 shall be common
stock, $0.01 par value per share ("Common Stock"), and 10,000,000 shall be
preferred stock, $0.01 par value per share ("Preferred Stock"). The preferences,
qualifications, limitations, restrictions and special or relative rights of each
class of stock are as set forth below:

     A.   Common Stock. All shares of Common Stock will be identical and will
        entitle holders thereof to the same preferences, qualifications,
        limitations, restrictions and relative and special rights.

        (1) Voting Rights. Each outstanding share of Common Stock shall be
        entitled to vote on each matter on which the stockholders of the
        corporation shall be entitled to vote, and each holder of Common Stock
        shall be entitled to one vote for each share of such Common Stock held
        by such holder.

        (2) Preemptive Rights. The holders of Common Stock shall not have
        preemptive rights to acquire additional shares of the stock of the
        corporation.

        (3) Cumulative Voting. The holders of Common Stock shall not be entitled
        to cumulate their shares for the purpose of electing directors of the
        corporation, or for any other purpose.

        (4) Dividends. The Board of Directors of the corporation (the "Board of
        Directors") may cause dividends to be paid to holders of shares of
        Common Stock out of funds legally available for the payment of
        dividends. Any dividend or distribution on the Common Stock shall be
        subject to the rights of the holders of the Preferred Stock.

        (5) Liquidation. In the event of any voluntary or involuntary
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        liquidation, dissolution or winding up of the corporation, the holders
        of the Common Stock shall be entitled, after payment or provision for
        payment of the debts and other liabilities of the corporation and the
        payment to the holders of the Preferred Stock of any preference on
        distributions in the liquidation, dissolution or winding up of the
        corporation, to share on a per share basis in the remaining net assets
        of the corporation.

     B.   Preferred Stock. The Preferred Stock may be divided into, and may be
        issued from time to time in, one or more series. The Board of Directors
        is authorized from time to time to establish and designate one or more
        series of Preferred Stock, in addition to the series established and
        designated in this Article FOURTH, by fixing and determining the
        variations in the relative rights and preferences as between and among
        such series and any other classes of capital stock of the corporation
        and fixing or altering the number of shares comprising any such series
        and the designation thereof. The authority of the Board of Directors
        from time to time with respect to each subsequent series of Preferred
        Stock shall include, but not be limited to, determination of the
        following: (1) the designation of the series; (2) the number of shares
        of the series and (except where otherwise provided in the creation of
        the series) any subsequent increase or decrease therein; (3) the
        dividends, if any, for shares of the series and the rates, conditions,
        times, and relative preferences thereof; (4) the redemption rights, if
        any, and price or prices for shares of the series; (5) the terms and
        amount of any sinking fund provided for the purchase or redemption of
        shares of the series; (6) the relative rights of shares of the series in
        the event of any voluntary or involuntary liquidation, dissolution or
        winding up of the affairs of the corporation; (7) whether the shares of
        the series shall be convertible into shares of any other class or series
        of shares of the corporation, and, if so, the specification of such
        other class or series, the conversion price or prices or rate or rates,
        any adjustments thereof, the date or dates as of which such shares shall
        be convertible and all other terms and conditions upon which such
        conversion may be made; (8) the voting rights, if any, of the holders of
        such series; and (9) such other designations, powers, preferences and
        relative, participating, optional or other special rights, and
        qualifications, limitations or restrictions thereof.
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        Subject to the foregoing powers of the Board of Directors with respect
        to series of Preferred Stock, the following is a statement of the
        designation of a series of Preferred Stock designated Convertible
        Preferred Stock, which shall consist of 45,684 shares, and the powers,
        preferences and relative rights, qualifications, limitations and
        restrictions thereof:

        (1) Voting Rights. Each outstanding share of Convertible Preferred Stock
        shall be entitled to vote on each matter on which the stockholders of
        the corporation shall be entitled to vote, and each holder of
        Convertible Preferred Stock shall have the voting rights equal to the
        number of shares of Common Stock such Convertible Preferred Stock is
        convertible into on the record date of any matter to be voted on by the
        stockholders of the corporation.

        (2) Preemptive Rights. The holders of Convertible Preferred Stock shall
        not have preemptive rights to acquire additional shares of the stock of
        the corporation.

        (3) Cumulative Voting. The holders of Convertible Preferred Stock shall
        not be entitled to cumulate their shares for the purpose of electing
        directors of the corporation, or for any other purpose.

        (4) Dividends. The Board of Directors may cause dividends to be paid to
        holders of shares of Convertible Preferred Stock out of funds legally
        available for the payment of dividends. Any dividend or distribution on
        the Convertible Preferred Stock shall be paid at the same rate and in
        the same manner as on the Common Stock.

        (5) Conversion Rights. Each share of the Convertible Preferred Stock
        shall be converted at any time at the option of the holder thereof

        at the office of the corporation or any transfer agent for the
        Convertible Preferred Stock into such number (rounding to the closest
        whole number) of fully paid and non-assessable shares of Common Stock of
        the corporation as is determined by dividing the number of shares of
        Convertible Preferred Stock being converted by 0.1125.

        (6) Liquidation.
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          (a) In the event of any voluntary or involuntary liquidation,
        dissolution or winding up of the corporation, then, before any
        distribution or payment shall be made to or set apart for the holders of
        Common Stock, the holders of the Convertible Preferred Stock shall be
        entitled to receive from the assets of the corporation, with respect to
        each share of Convertible Preferred Stock held, an amount equal to
        $100.00 per share (the "Convertible Preferred Liquidation Preference")
        (such amount to be adjusted appropriately in the event of any stock
        dividend, stock split or a combination, or a similar recapitalization
        affecting the Convertible Preferred Stock) plus, in the case of each
        share, an amount equal to any dividend declared but unpaid thereon. If,
        upon the occurrence of any such liquidation, dissolution or winding up,
        the assets to be thus distributed among the holders of the Convertible
        Preferred Stock shall be insufficient to permit the payment to such
        holders of the full aforesaid preferential amount, then each issued and
        outstanding share of Convertible Preferred Stock shall entitle the
        holder thereof to a proportion of the assets to be distributed on a pro
        rata basis according to the Convertible Preferred Liquidation
        Preference, and the holders of the Common Stock shall in no event be
        entitled to participate in any such distribution in respect of their
        shares.

          (b) A merger or consolidation of the corporation into or with any
        other corporation, a merger of any other corporation into the
        corporation, or a sale, lease, exchange, transfer or similar disposition
        (other than a mortgage, grant of a security interest or pledge) by the
        corporation in one or a series of related transactions of all or
        substantially all of its assets shall be deemed, for purposes of this
        section (6) to be a liquidation, dissolution or winding up of the
        corporation unless, in the case of any such merger or consolidation, (i)
        the holders of Convertible Preferred Stock retain their existing shares
        of Convertible Preferred Stock or receive a security of the surviving or
        resulting corporation which entitles them to substantially equivalent
        rights and obligations as those of the Convertible Preferred Stock held
        by them or (ii) the holders of at least sixty percent (60%) of the then
        outstanding shares of the Convertible Preferred Stock agree that such
        merger or a consolidation or sale shall not be deemed a liquidation,
        dissolution or winding up of the corporation. Written notice of any
        proposed merger, consolidation, sale, lease, exchange, transfer or
        similar disposition meeting the foregoing
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        description, in reasonable detail, shall be furnished to the holders of
        the Convertible Preferred Stock no later than thirty (30) days prior to
        the anticipated effective date thereof.

     FIFTH: The name and mailing address of the sole incorporator is as follows:

                   Name                   Mailing Address
                   ----                   ---------------

                   N.S. Truax            1013 Centre Road
                                         City of Wilmington, County of New
                                         Castle, Delaware 19904

     SIXTH: The corporation is to have perpetual existence.

     SEVENTH: Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this corporation under
Section 291 of Title 8 of the Delaware Code or on the application of trustees in
dissolution or of any receiver or receivers appoint for this corporation under
Section 279 of Title 8 of the Delaware Code order a meeting of the creditors or
class of creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, to be summoned in such manner as the said court
directs. If a majority in number representing three-fourths in value of the
creditors or class of creditors, and/or of the stockholders or class of
stockholders of this corporation, as the case may be, agree to any compromise or
arrangement and to any reorganization of this corporation as consequent of such
compromise or arrangement, the said compromise or arrangement and the said
reorganization shall, if sanctioned by the court to which the said application
has been made, be binding on all the creditors or class of creditors, and/or on
all the stockholders or class of stockholders, of this corporation, as the case
may be, and also on this corporation.

     EIGHTH: The management of the business and the conduct of the affairs of
the Corporation shall be vested in the Board of Directors. In furtherance and
not in limitation of the powers conferred by statute, the Board of Directors is
expressly authorized:

     To make, alter, amend, or repeal the by-laws of the corporation.

     To authorize and cause to be executed mortgages and liens upon the real
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and personal property of the corporation.

         To set apart out of any of the funds of the corporation available for
dividends a reserve or reserves for any proper purpose and to abolish any such
reserve in the manner in which it was created.

         When and as authorized by the stockholders in accordance with statute,
to sell, lease or exchange all or substantially all of the property and assets
of the corporation, including its good will and its corporate franchises, upon
such terms and conditions and for such consideration, which may consist in whole
or in part of money or property including shares of stock in, and/or other
securities of, any other corporation or corporations, as its Board of Directors
shall deem expedient and for the best interests of the corporation.

         To determine the extent, if any, to which and the time and place at
which, and the conditions under which any stockholder of the Corporation may
examine books and records now or hereafter required by statute to be kept open
for inspection of stockholders of the Corporation.

         To provide, in any vote or votes authorizing liquidation of the
Corporation or proceedings for its dissolution, for the distribution pro rata
among the stockholders of the Corporation of assets of the Corporation, wholly
or in part or kind, whether such assets be in cash or other property, that the
board of directors of the Corporation may determine the value of the different
assets of the Corporation for the purpose of such liquidation and that the board
of directors may divide or authorize the division of such assets of the
Corporation or any part thereof among the stockholders and the Corporation so
that each stockholder will receive a proportionate amount in value (determined
as aforesaid) of cash or property of the Corporation upon such liquidation or
dissolution even though every stockholder may not receive a strictly
proportionate part of each such asset.

         NINTH: Meetings of stockholders may be held at such place, either
within or without the State of Delaware, as the by-laws may provide. The books
of the corporation may be kept (subject to any provision contained in the
statutes) outside the State of Delaware at such place or places as may be
designated from time to time by the Board of Directors or in the by-laws of the
corporation. Elections of directors need not be by written ballot unless the
by-laws of the corporation shall so provide.

         TENTH: Any amendment, repeal, or other alteration of this First
Restated Certificate of Incorporation shall, unless proposed and declared
advisable by the Board of Directors, require the affirmative vote of at least
two-thirds of the outstanding shares of capital stock of the corporation
entitled to vote in the election of directors. Subject to the foregoing, the
corporation reserves the right to amend, alter, change or repeal any provision
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contained in this certificate of incorporation, in the manner now or hereafter
prescribed by statute and this certificate of incorporation, and all rights
conferred upon a stockholder, director or officer herein, are granted subject to
this reservation.

         ELEVENTH: Whenever the corporation shall be authorized to issue more
than one class of stock, no outstanding share of any class of stock which is
denied voting power under the provisions of the certificate of incorporation
shall entitle the holder thereof to the right to vote at any meeting of
stockholders except as the provisions of paragraph (2) of subsection (b) of
Section 242 of the General Corporation Law of the State of Delaware shall
otherwise require; provided, that no share of any such class which is otherwise
denied voting power shall entitle the holder thereof to vote upon the increase
or decrease in the number of authorized shares of said class.

         TWELFTH: No director of the corporation shall be personally liable to
the corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except for liability, (i) for any breach of the director's
duty of loyalty to the corporation or its stockholders, (ii) for acts of
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived an improper
personal benefit. If the Delaware General Corporation Law is amended after
approval by the stockholders of this Article TWELFTH to authorize corporate
action further eliminating or limiting the personal liability of directors, then
the liability of a director of the corporation shall be eliminated or limited to
the fullest extent permitted by the Delaware General Corporation Law, as so
amended from time to time. Any repeal or modification of this Article TWELFTH
shall not increase the personal liability of any director of the corporation for
any act or occurrence taking place prior to such repeal or modification, or
otherwise adversely affect any right or protection of a director of the
corporation existing hereunder prior to the time of such repeal or modification.

         THIRTEENTH: The corporation shall, to the fullest extent permitted
under the General Corporation Law of the State of Delaware, as amended from time
to time, indemnify each of its directors, officers, employees and agents (each
an "Indemnified Party") against all expenses (including, without limitation,
attorneys' fees and expenses), liabilities, judgments, fines and amounts paid or
otherwise due in respect of any action, suit or proceeding in which such
Indemnified Party may be involved or with which he may be threatened, as a party
or otherwise, whether or not he continues to be such at the time such expenses
and liabilities shall have been imposed or incurred, by reason of his actions or
omissions in connection with services rendered directly or indirectly to the
corporation, such indemnification to include prompt payment of expenses in
advance of the final disposition of any such action, suit or proceeding.
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FOURTEENTH:

         (a)  Number, Terms and Election of Directors.

         Subject to the rights, if any, of the holders of any class or series of
Preferred Stock to elect additional directors under specified circumstances, the
number of directors of the corporation shall be fixed and may be increased or
decreased from time to time by the Board of Directors, but in no case shall the
number be less than three nor more than fifteen.

         The directors shall be divided into three classes, as nearly equal in
number as possible. One class of directors has been initially elected for a term
expiring at the annual meeting of stockholders to be held in 1998, another class
of directors has been initially elected for a term expiring at the annual
meeting of stockholders to be held in 1999, and another class of directors has
been initially elected for a term expiring at the annual meeting of stockholders
to be held in 2000, with members of each class to hold office until their
successors are elected and qualified. At each succeeding annual meeting of the
stockholders of the corporation, the successors of the class of directors whose
term expires at that meeting shall be elected by plurality vote of all votes
cast at such meeting to hold office for a term expiring at the annual meeting of
stockholders held in the third year following their year of election.

         (b)  Newly Created Directorships and Vacancies.

         Subject to the rights, if any, of the holders of any and all series of
Preferred Stock to elect additional directors pursuant to the terms and
conditions of such Preferred Stock, newly created directorships resulting from
any increase in the number of directors and any vacancies on the Board of
Directors resulting from death, resignation, disqualification, removal or other
cause shall be filled solely by the affirmative vote of a majority of the
remaining directors then in office, even though less than a quorum of the board
of directors, or by a sole remaining director. Any director elected in
accordance with the preceding sentence shall hold office for the remainder of
the full term of the class of directors in which the new directorship was
created or the vacancy occurred and until such director's successor shall have
been elected and qualified. No decrease in the number of directors constituting
the Board of Directors shall shorten the term of an incumbent director.

        (c)  Removal.

         Subject to the rights, if any, of the holders of any and all series of
Preferred Stock to elect additional directors pursuant to the terms and
conditions of such Preferred Stock, any director may be removed from office by
the stockholders only for cause and only in the following manner. At any annual
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meeting or special meeting of the stockholders of the corporation, the notice of
which shall state that the removal of a director or directors is among the
purposes of the meeting, the affirmative vote of the holders of at least a
majority of the outstanding shares of capital stock of the corporation entitled
to vote generally in the election of the directors, voting together as a single
class, may remove such director or directors for cause.

         FIFTEENTH:  Subject to the rights of the holders of any and all series
of Preferred Stock:

                  (a) any action required or permitted to be taken by the
         stockholders of the corporation must be effected at a duly called
         annual or special meeting of the stockholders of the corporation and
         may not be effected by any consent in writing of such stockholders; and

                  (b) special meetings of stockholders of the corporation may be
         called only by the Chairman of the Board of Directors or the Chief
         Executive Officer of the corporation or by the Secretary of the
         corporation within ten (10) days after receipt of the written request
         of a majority of the Board of Directors.


         [Signatures appear on the following page.]
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        IN WITNESS WHEREOF, said NEXAR TECHNOLOGIES, INC. has caused its
corporate seal to be hereunto affixed and this First Restated Certificate of
Incorporation to be signed by Albert J. Agbay, its President, and attested by
Steven Georgiev, its Secretary, this 14th day of April, 1997.

                                By:
                                    Albert J. Agbay, President


ATTEST:

Steven Georgiev, Secretary

[Corporate Seal]