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                                                                    Exhibit 3.1
                                                                    -----------

                         CERTIFICATE OF INCORPORATION
                                      OF
                      ARDIS TELECOM & TECHNOLOGIES, INC.


     FIRST:    The name of the Corporation is ARDIS Telecom & Technologies, Inc.
(the "Corporation").

     SECOND:   The name and mailing address of the Incorporator of the
Corporation is William L. Rivers, c/o Arter & Hadden LLP, 1717 Main Street,
Suite 4100, Dallas, Texas 75201.

     THIRD:    The address of its registered office in the State of Delaware is
1209 Orange Street, in the City of Wilmington, County of New Castle 19801.  Its
registered agent at such address is The Corporation Trust Company.

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

     FIFTH:    The Corporation is to have perpetual existence.

     SIXTH:    The aggregate number of shares of all classes of stock which the
corporation shall have authority to issue is Fifty-four Million One Hundred
Sixty-nine Thousand One Hundred (54,169,100) shares, consisting of (A) Forty-
four Million One Hundred Sixty-nine Thousand One Hundred (44,169,100) shares of
common stock, par value $0.001 per share (the "Common Stock"), and (B) Ten
Million (10,000,000) shares of preferred stock, par value $0.0001 per share (the
"Preferred Stock").

     The designations, powers, preferences and relative, participating, optional
and other special rights, and the qualifications, limitations and restrictions
thereof with respect to the Common Stock and the Preferred Stock are as follows:

(A)  Common Stock.

     Each holder of the Common Stock of the Corporation shall be entitled to one
vote for every share of Common Stock outstanding in his name on the books of the
Corporation.  Except for and subject to those rights expressly granted to the
holders of the Preferred Stock or except as may be provided by the laws of the
State of Delaware, the holders of Common Stock shall have exclusively all other
rights of stockholders including, without limitation, (i) the right to receive
dividends, when and as declared by the Board of Directors out of assets legally
available therefor, and (ii) in the event of any distribution of assets upon
liquidation, dissolution or winding up of the Corporation or otherwise, the
right to receive ratably and equally with all holders of all Common Stock all
the assets and funds of the Corporation remaining after the payment to the
holders of the Preferred


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Stock of the specific amounts that they are entitled to receive upon such
liquidation, dissolution or winding up of the Corporation, if any.

(B)  Preferred Stock.

     Preferred Stock may be issued from time to time in one or more series, each
of such series to have such terms as stated in the resolution or resolutions
providing for the establishment of such series adopted by the Board of Directors
of the corporation as hereinafter provided. Except as otherwise expressly stated
in the resolution or resolutions providing for the establishment of a series of
Preferred Stock, any shares of Preferred Stock that may be redeemed, purchased
or acquired by the Corporation may be reissued except as otherwise expressly
provided by law. Different series of Preferred Stock shall not be construed to
constitute different classes of stock for the purpose of voting by classes
unless expressly provided in the resolution or resolutions providing for the
establishment thereof. The Board of Directors of the Corporation is hereby
expressly authorized to issue, from time to time, shares of Preferred Stock in
one or more series, and, in connection with the establishment of any such series
by resolution or resolutions, to determine and fix the number of shares
constituting that series and the distinctive designation of that series and to
determine and fix such voting powers, full or limited, or no voting powers, and
such other powers, designations, preferences and relative, participating,
optional and other rights, and the qualifications, limitations and restrictions
thereof, including, without limitation, dividend rights, conversion rights,
redemption privileges and liquidation preferences, as shall be stated in such
resolution or resolutions, all to the fullest extent permitted by the Delaware
General Corporation law (the "DGCL"). Without limiting the generality of the
foregoing, the resolution or resolutions providing for the establishment of any
series of Preferred Stock may, to the extent permitted by law, provide that such
series shall be superior to, rank equally with or be junior to the Preferred
Stock of any other series. Except as otherwise expressly provided in the
resolution or resolutions providing for the establishment of any series of
Preferred Stock, no vote of the holders of shares of Preferred Stock or Common
Stock shall be a prerequisite to the issuance of any shares of any series of the
Preferred Stock authorized by and complying with the conditions of this
Certificate of Incorporation.

     SEVENTH:  In furtherance and not in limitation of the powers conferred on
it by the laws of the State of Delaware, the Board of Directors is expressly
authorized to adopt, amend or repeal the Bylaws of the Corporation.

     EIGHTH:   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 stockholders to consent in writing, without
a meeting, to the taking of any action is specifically denied.

     NINTH:    No director of the Corporation shall be personally liable to the
Corporation or any of its stockholders for monetary damages for breach of
fiduciary duty as a director of the Corporation; PROVIDED, HOWEVER, that the
foregoing is not intended to eliminate or limit the liability of a director of
the Corporation for (i) any breach of a director's duty of loyalty to the
Corporation or its stockholders, (ii) acts or omissions not in good faith or
which involve intentional


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misconduct or a knowing violation of law, (iii) a violation of Section 174 of
the DGCL, or (iv) any transaction from which the director derived an improper
personal benefit. No amendment to or repeal of this Article NINTH shall apply to
or have any effect on the liability or alleged liability of any director of the
Corporation for or with respect to any acts or omissions of such director
occurring prior to such amendment.

     TENTH:    The Corporation shall, to the fullest extent permitted by Section
145 of the DGCL, as that section may be amended and supplemented from time to
time, indemnify any director or officer of the Corporation (and any director,
trustee or officer of any corporation, business trust or other entity to whose
business the Corporation shall have succeeded) which it shall have power to
indemnify under that Section against any expenses, liabilities or other matter
referred to in or covered by that Section. The indemnification provided for in
this Article TENTH (a) shall not be deemed exclusive of any other rights to
which those indemnified may be entitled under any Bylaw, agreement or vote of
stockholders or disinterested directors or otherwise, both as to action in their
official capacities and as to action in another capacity while holding such
office, (b) shall continue as to a person who has ceased to be a director or
officer and (c) shall inure to the benefit of the heirs, executors and
administrators of such a person. To assure indemnification under this Article
TENTH of all such persons who are determined by the Corporation or otherwise to
be or to have been "Fiduciaries" of any employee benefit plan of the Corporation
which may exist from time to time and which is governed by the Act of Congress
entitled "Employee Retirement Income Security Act of 1974," as amended from time
to time, such Section 145 shall, for the purposes of this Article, be
interpreted as follows: an "other enterprise" shall be deemed to include such an
employee benefit plan; the Corporation shall be deemed to have requested a
person to serve an employee benefit plan where the performance by such person of
his duties to the Corporation also imposes duties on, or otherwise involves
services by, such person to the plan or participants or beneficiaries of the
plan; excise taxes assessed on a person with respect to an employee benefit plan
pursuant to such Act of Congress shall be deemed "fines;" and action taken or
omitted by a person with respect to an employee benefit plan in the performance
of such person's duties for a purpose reasonably believed by such person to be
in the interest of the participants and beneficiaries of the plan shall be
deemed to be for a purpose which is not opposed to the best interests of the
Corporation.

     ELEVENTH:  Notwithstanding anything contained in this Certificate of
Incorporation to the contrary, the affirmative vote of at least 662/3% of the
outstanding shares of the Common Stock of the Corporation shall be required to
amend or repeal Articles EIGHTH and TENTH of this Certificate of Incorporation
or to adopt any provision inconsistent therewith. Further, the affirmative vote
of at least 662/3% of the outstanding shares of the Common Stock of the
Corporation shall be required to amend or repeal the Bylaws of the Corporation,
if the stockholders of the Corporation are required by the DGCL, the Certificate
of Incorporation or the Bylaws to vote thereon.  Except as provided herein, the
Corporation reserves the right to amend, alter, change or repeal any provision
contained in this Certificate of Incorporation in the manner now or hereafter
prescribed by the laws of the State of Delaware, and all rights herein conferred
are granted subject to this reserved power.


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     TWELFTH:  Meetings of stockholders may be held within or without the State
of Delaware as the Bylaws may provide. The books of the Corporation may be kept
(subject to any provision contained in the Delaware General Corporation Law)
outside the State of Delaware at such place or places as may be designated form
time to time by the Board of Directors or in the Bylaws of the Corporation.

     IN WITNESS WHEREOF, I have hereunto set my hand this 30th day of December,
1998, and affirm the statements contained therein as true under penalties of
perjury.



                                                       /s/ William L. Rivers
                                                       ---------------------
                                                       William L. Rivers
                                                       Incorporator



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                           CERTIFICATE OF AMENDMENT
                                      OF
                         CERTIFICATE OF INCORPORATION
                                      OF
                      ARDIS TELECOM & TECHNOLOGIES, INC.



     ARDIS TELECOM & TECHNOLOGIES, INC (the "Corporation"), a corporation
organized and existing under and by virtue of the General Corporation Law of the
State of Delaware ("DGCL"),


DOES HEREBY CERTIFY THAT:

     FIRST:  The name of the Corporation is ARDIS TELECOM & TECHNOLOGIES, INC.

     SECOND:  The Board of Directors of the Corporation (the "Board"), at a
special meeting held on November 23, 1999, did unanimously adopt resolutions
approving the amendment to the Corporation's Certificate of Incorporation.  The
resolution setting forth the proposed amendment is as follows:

     RESOLVED, that ARTICLE I of the Certificate of Incorporation of the
Corporation be amended to read in its entirety as follows:

                                  "ARTICLE I

       The name of the Corporation is : DIAL-THRU INTERNATIONAL CORPORATION"

     THIRD:  That the proposed amendment to ARTICLE I of the Certificate of
Incorporation of the Corporation was submitted to the stockholders of the
Corporation at a special meeting held on  January 14, 2000 and the stockholders
of the Corporation duly adopted, approved and confirmed such amendment to
ARTICLE I of the Certificate of Incorporation.

     FOURTH:  That said amendment was duly adopted in accordance with Section
242 of the DGCL.



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     IN WITNESS WHEREOF, the undersigned has caused this Certificate of
Amendment of Certificate of Incorporation to be executed as of this 14th day of
January, 2000.

                                       ARDIS TELECOM & TECHNOLOGIES, INC


                                       By:   /s/ Roger D. Bryant
                                             ----------------------------
                                       Name: Roger D. Bryant,
                                             Chairman




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