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                                                                     Exhibit 3.1

                  THIRD RESTATED CERTIFICATE OF INCORPORATION
                                      OF
                                  ITXC CORP.

     ITXC Corp. (the "Corporation"), a Delaware corporation, hereby certifies as
follows:

     1.  The name of the Corporation is ITXC Corp.

     2.  The original certificate of incorporation of the Corporation was filed
with the Secretary of State of Delaware on July 21, 1997.  A restated
certificate of incorporation of the Corporation was filed with the Secretary of
State of Delaware on April 22, 1998.  A second restated certificate of
incorporation of the Corporation was filed with the Secretary of State of
Delaware on February 23, 1999.

     3.  This third restated certificate of incorporation of the Corporation has
been duly adopted in accordance with Sections 242 and 245 of the General
Corporation Law of the State of Delaware.

     4.  This third restated certificate of incorporation amends, restates and
integrates the provisions of the certificate of incorporation of the
Corporation.

     5.  The text of the certificate of incorporation of the Corporation is
hereby amended, restated and integrated to read in its entirety as follows:

     FIRST:  The name of the corporation is ITXC Corp. (the "Corporation").
     -----

     SECOND:  The registered office of the Corporation is located at 9 East
     ------
Loockerman Street, in the City of Dover, in the County of Kent, in the State of
Delaware.  The name of its registered agent at that address is National
Registered Agents, Inc.

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

     FOURTH:  The total number of shares of stock which the Corporation shall
     ------
have authority to issue is Eighty Two Million Five Hundred Thousand (82,500,000)
shares, of which Sixty Seven Million Five Hundred Thousand (67,500,000) shares
are designated as Common Stock, having a par value of $.001 per share ("Common
Stock"), and Fifteen Million (15,000,000) shares are designated as Preferred
Stock, having a par value of $.001 per share ("Preferred Stock").
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     The  Preferred Stock may be issued from time to time in one or more series.
The Board of Directors is hereby authorized to provide for the issuance of
shares of Preferred Stock in one or more series and, by filing a certificate
pursuant to the applicable law of the State of Delaware (hereinafter referred to
as "Preferred Stock Designation"), to establish from time to time the number of
shares to be included in each such series, and to fix the designation, powers,
preferences and rights of the shares of each such series and the qualifications,
limitations and restrictions thereof.  The authority of the Board of Directors
with respect to each series shall include, but not be limited to, determination
of the following:

          (a)  The designation of the series, which may be by distinguishing
number, letter or title.

          (b)  The number of shares of the series, which number the Board of
Directors may thereafter (except where otherwise provided in the Preferred Stock
Designation) increase or decrease (but not below the number of shares thereof
then outstanding).

          (c)  The amounts payable on, and the preferences, if any, of shares of
the series in respect of dividends, and whether such dividends, if any, shall be
cumulative or noncumulative.

          (d)  Dates at which dividends, if any, shall be payable.

          (e)  The redemption rights and price or prices, if any, for shares of
the series.

          (f)  The terms and amount of any sinking fund provided for the
purchase or redemption of shares of the series.

          (g)  The amounts payable on, and the preferences, if any, of shares of
the series in the event of any voluntary or involuntary liquidation, dissolution
or winding up of the affairs of the Corporation.

          (h)  Whether the shares of the series shall be convertible into or
exchangeable for shares of any other class or series, or any other security, of
the Corporation or any other corporation, and, if so, the specification of such
other class or series or such other security, the conversion or exchange price
or prices or rate or rates, any adjustments thereof, the date or dates at which
such shares shall be convertible or exchangeable and all other terms and
conditions upon which such conversion or exchange may be made.

          (i)  Restrictions on the issuance of shares of the same series or of
any other class or series.

                                      -2-
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          (j)  The voting rights, if any, of the holders of shares of the
series.

     The Common Stock shall be subject to the express terms of the Preferred
Stock and any series thereof.  Except as may otherwise be provided in this
restated certificate of incorporation, in a Preferred Stock Designation or by
applicable law, the holders of shares of Common Stock shall be entitled to one
vote for each such share upon all questions presented to the stockholders, the
Common Stock shall have the exclusive right to vote for the election of
directors and for all other purposes, and holders of Preferred Stock shall not
be entitled to vote at or receive notice of any meeting of stockholders.

     Subject to the rights of the holders of any series of Preferred Stock
pursuant to the terms of this restated certificate of incorporation or any
resolution or resolutions providing for the issuance of such series of stock
adopted by the Board of Directors, the number of authorized shares of Preferred
Stock or Common Stock may be increased or decreased (but not below the number of
shares thereof then outstanding) by the affirmative vote of the holders of a
majority of the stock of the Corporation entitled to vote generally in the
election of directors irrespective of the provisions of Section 242(b)(2) of the
General Corporation Law of the State of Delaware.

     FIFTH:  The authorized number of members of the Board of Directors will be
     -----
fixed from time to time by resolution adopted by the affirmative vote of a
majority of the entire Board of Directors but in no event may the number be less
than three.

     The Directors shall be divided into three classes, each consisting of one-
third of such directors, as nearly as may be, designated Class I, Class II and
Class III.  Class I directors shall initially serve until the 2000 meeting of
stockholders; Class II directors shall initially serve until the 2001 meeting of
stockholders; and Class III directors shall initially serve until the 2002
meeting of stockholders.  Commencing with the stockholders' meeting in 2000, and
at each succeeding annual stockholders' meeting, successors to the class of
directors whose term expires at such annual stockholders' meeting shall be
elected for a three-year term.  If the number of such directors is changed, an
increase or decrease in such directors shall be apportioned among the classes so
as to maintain the number of directors comprising each class as nearly equal as
possible, and any additional directors of any class shall hold office for a term
which shall coincide with the remaining term of such class.  A director shall
hold office until the annual stockholders' meeting for the year in which his
term expires and until his successor shall be elected and shall qualify,
subject, however, to prior death, resignation, retirement, disqualification, or
removal from office.

     Except as otherwise required by law, any vacancy on the board of directors
that results from an increase in the number of directors and any other vacancy
occurring in the board of directors shall only be filled by a majority of the
directors then in office, even if less than a quorum, or by a sole remaining
director.  Any director elected to fill a vacancy not resulting from an increase
in the number of directors shall have the same remaining term as that of his or
her predecessor.  A director may be removed only for cause by the stockholders.

                                      -3-
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     Notwithstanding the foregoing, whenever the holders of any one or more
series of Preferred Stock issued by the Corporation shall have the right, voting
separately by class or series, to elect directors at an annual or special
meeting of stockholders, the election, term of office, filling of vacancies and
other features of such directorships shall be governed by the terms of this
restated certificate of incorporation applicable thereto and such directors so
elected shall not be divided into classes pursuant to this Article Fifth, in
each case unless expressly provided by such terms.  During any period when the
holders of any series of Preferred Stock have the right to elect additional
directors as provided for or fixed pursuant to the provisions of Article Fourth
hereof, then upon commencement and for the duration of the period during which
such right continues:  (i) the then otherwise total authorized number of
directors of the Corporation shall automatically be increased by such specified
number of directors, and the holders of such Preferred Stock shall be entitled
to elect the additional directors so provided for or fixed pursuant to said
provisions, and (ii) each such additional director shall serve until such
director's successor shall have been duly elected and qualified, or until such
director's right to hold such office terminates pursuant to said provisions,
whichever occurs earlier, subject to his earlier death, disqualification,
resignation or removal.  Except as otherwise provided by the Board of Directors
in the resolution or resolutions establishing such series, whenever the holders
of any series of Preferred Stock having such right to elect additional directors
are divested of such right pursuant to the provisions of such stock, the terms
of office of all such additional directors elected by the holders of such stock,
or elected to fill any vacancies resulting from the death, resignation,
disqualification or removal of such additional directors, shall forthwith
terminate and the total and authorized number of directors of the Corporation
shall be reduced accordingly.

     SIXTH: Meetings of stockholders may be held 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. The election of
directors need not be by written ballot unless the By-laws so provide.

     SEVENTH: The Board of Directors of the Corporation is authorized and
     -------
empowered from time to time in its discretion to make, alter, amend or repeal
By-laws of the Corporation.

     EIGHTH:  A director of the Corporation shall not be liable to the
     ------
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director, except to the extent such exemption from liability or
limitation thereof is not permitted under the General Corporation Law of the
State of Delaware, as the same exists or may hereafter be amended.  Any
amendment, modification or repeal of the foregoing sentence shall not adversely
affect any right or protection of a director of the Corporation hereunder in
respect of any act or omission occurring prior to the time of such amendment,
modification or repeal.

                                      -4-
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     NINTH:
     -----

     1.  Right to Indemnification.  The Corporation shall indemnify and hold
harmless, to the fullest extent permitted by applicable law as it presently
exists or may hereafter be amended, any person (an "Covered Person") who was or
is made or is threatened to be made a party or is otherwise involved in any
action, suit or proceeding, whether civil, criminal, administrative or
investigative (a "Proceeding"), by reason of the fact that he or she, or a
person for whom he or she is the legal representative, is or was a director or
officer of the Corporation or, while a director or officer of the Corporation,
is or was serving at the request of the Corporation as a director, officer,
employee, manager or agent of another corporation or of a partnership, limited
liability company, joint venture, trust, enterprise or nonprofit entity,
including service with respect to employee benefit plans, against all liability
and loss suffered and expenses (including attorneys' fees) reasonably incurred
by such Covered Person.   Notwithstanding the preceding sentence, except as
otherwise provided in Section 3 of this Article Ninth, the Corporation shall be
required to indemnify an Covered Person in connection with a Proceeding (or part
thereof) commenced by such Covered Person only if the commencement of such
Proceeding (or part thereof) by the Covered Person was authorized by the Board
of Directors of the Corporation.  Notwithstanding any provision herein to the
contrary, the Corporation shall not be required to advance expenses to an
Covered Person who is a party to an action, suit or proceeding brought by the
Corporation and approved by a majority of the Board of Directors of the
Corporation which alleges willful misappropriation of corporate assets by such
Covered Person, disclosure of confidential information in violation of such
Covered Person's fiduciary or contractual obligations to the Corporation or any
other willful and deliberate breach in bad faith of such Covered Person's duty
to the Corporation or its stockholders.

     2.  Prepayment of Expenses.  Except as otherwise provided in Section 1 of
this Article Ninth, the Corporation shall pay the expenses (including attorneys'
fees) incurred by an Covered Person in defending any Proceeding in advance of
its final disposition, provided, however, that to the extent required by law,
                       -----------------
such payment of expenses in advance of the final disposition of the Proceeding
shall be made only upon receipt of an undertaking by the Covered Person to repay
all amounts advanced if it should be ultimately determined that the Covered
Person is not entitled to be indemnified under this Article Ninth or otherwise.

     3.  Claims.  If a claim for indemnification or advancement of expenses
under this Article Ninth is not paid in full within sixty days after a written
claim therefor by the Covered Person has been received by the Corporation, the
Covered Person may file suit to recover the unpaid amount of such claim and, if
successful in whole or in part, shall be entitled to be paid the expense of
prosecuting such claim.  In any such action the Corporation shall have the
burden of proving that the Covered Person is not entitled to the requested
indemnification or advancement of expenses under applicable law.

                                      -5-
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     4.  Nonexclusivity of Rights.  The rights conferred on any Covered Person
by this Article Ninth shall not be exclusive of any other rights which such
Covered Person may have or hereafter acquire under any statute, provision of
this restated certificate of incorporation, the Corporation's by-laws or any
agreement, vote of stockholders or disinterested directors or otherwise.

     5.  Other Sources.  The Corporation's obligation, if any, to indemnify or
to advance expenses to any Covered Person who was or is serving at its request
as a director, officer, employee, manager or agent of another corporation,
partnership, limited liability company, joint venture, trust, enterprise or
nonprofit entity shall be reduced by any amount such Covered Person may collect
as indemnification or advancement of expenses from such other corporation,
partnership, limited liability company, joint venture, trust, enterprise or non-
profit enterprise.

     6.  Amendment or Repeal.  Any repeal or modification of the foregoing
provisions of this Article Ninth shall not adversely affect any right or
protection hereunder of any Covered Person in respect of any act or omission
occurring prior to the time of such repeal or modification.

     7.  Other Indemnification and Prepayment of Expenses.  This Article Ninth
shall not limit the right of the Corporation, to the extent and in the manner
permitted by law, to indemnify and to advance expenses to persons other than
Covered Persons when and as authorized by appropriate corporate action.

     TENTH:  No action required to be taken or which may be taken at any annual
     -----
or special meeting of stockholders of the Corporation may be taken without a
meeting; and the power of the stockholders to consent in writing, without a
meeting, to the taking of any action is specifically denied.

     ELEVENTH:  Except as otherwise required by law, the provisions of Articles
     --------
Fifth and Tenth and the provisions of this Article Eleventh may not be amended
in any respect unless such amendment is approved by the affirmative vote of the
holders of two thirds in voting power of the outstanding stock of the
Corporation entitled to vote generally.

     IN WITNESS WHEREOF, ITXC Corp. has caused this certificate to be signed by
Edward B. Jordan, its Executive Vice President, on the 1ST day of October, 1999.


                                   ITXC CORP.


                                   /s/ Edward B. Jordan
                                   ____________________________________
                                   Edward B. Jordan, Executive Vice President


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                          CERTIFICATE OF AMENDMENT TO
                  THIRD RESTATED CERTIFICATE OF INCORPORATION
                                 OF ITXC CORP.

     ITXC Corp. (the "Corporation"), a Delaware corporation, hereby certifies as
follows:

                                   ARTICLE I

     1.1.  The name of the Corporation is ITXC Corp.

     1.2.  The original Certificate of Incorporation of the Corporation was
filed with the Secretary of State of Delaware on July 21, 1997.  A Restated
Certificate of Incorporation of the Corporation was filed with the Secretary of
State of Delaware on April 22, 1998.  A Second Restated Certificate of
Incorporation of the Corporation was filed with the Secretary of State of
Delaware on February 23, 1999.  A Third Restated Certificate of Incorporation of
the Corporation was filed with the Secretary of State of Delaware on October 1,
1999.

     1.3.  This Certificate of Amendment to the Third Restated Certificate of
incorporation of the Corporation has been duly adopted and approved in
accordance with Section 242 of the General Corporation Law of the State of
Delaware.

                                  ARTICLE II

     The First Paragraph of Article Fourth of the Corporation's certificate of
incorporation is amended to read in its entirety as follows:

     "The total number of shares of stock which the Corporation shall
     have authority to issue is Four Hundred and Fifteen Million
     (415,000,000) shares, of which Four Hundred Million (400,000,000)
     shares are designated as Common Stock, having a par value of
     $.001 per share ("Common Stock"), and Fifteen Million
     (15,000,000) shares are designated as Preferred Stock, having a
     par value of $.001 per share ("Preferred Stock")."

     IN WITNESS WHEREOF, ITXC Corp. has caused this certificate to be signed by
Edward B. Jordan, its Executive Vice President, on the 3rd day of May, 2000.

                                                  ITXC Corp.


                                                  By: /s/ Edward  B. Jordan
                                                      Edward B. Jordan,
                                                      Executive Vice President