EXHIBIT 3.4

                               ATSI MERGER CORP.

                         CERTIFICATE OF INCORPORATION


     THE UNDERSIGNED, acting as the incorporator of a corporation under and in 
accordance with the General Corporation Law of the State of Delaware, hereby 
adopts the following Certificate of Incorporation for such corporation:


                                  ARTICLE I.

                                     NAME

     The name of this company (the "Company") is ATSI Merger Corp.

                                  ARTICLE II.

                                   BUSINESS

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

                                 ARTICLE III.

                           AUTHORIZED CAPITAL STOCK

     A.   Authorization of Shares
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          The total number of shares of capital stock which the Company shall 
have the authority to issue is 55,000,000 shares, consisting of 50,000,000 
shares of common stock, par value $0.001 per share ("Common Stock"), and 
5,000,000 shares of preferred stock, par value $0.001 per share ("Preferred 
Stock").

     B.   Common Stock
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          (1)  Dividends. The holders of shares of Common Stock shall be
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     entitled to receive such dividends as from time to time may be declared by
     the Board of Directors of the Company, subject to any preferential payments
     to which the holders of shares of any series of Preferred Stock shall be
     entitled as may be stated and expressed pursuant to the resolution
     establishing any such series of Preferred Stock.

          (2)  Liquidation. In the event of any liquidation, dissolution or
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     winding up of the Company, whether voluntary or involuntary, after payment
     shall have been made to any holders of shares of any series of Preferred
     Stock then outstanding of the full amounts

 
     of preferential payments to which they shall respectively be entitled as
     may be stated and expressed pursuant to the resolution establishing any
     such series of Preferred Stock, the holders of shares of Common Stock then
     outstanding shall be entitled to share ratably based upon the number of
     shares of Common Stock held by them in all remaining assets of the Company
     available for distribution to its shareholders.

          (3)  Voting Rights. All shares of Common Stock shall be identical with
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     each other in every respect. The shares of Common Stock shall entitle the 
     holders thereof to one vote for each share upon all matters upon which 
     shareholders have the right to vote.

     C    Preferred Stock
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          The Board of Directors is authorized to establish, from time to time, 
one or more series of any class of shares, to increase or decrease the number 
within each series, and to fix the designations, powers, preferences and 
relative, participating, optional or other rights of such series and any 
qualifications, limitations or restrictions thereof.

                                  ARTICLE IV.

                               REGISTERED OFFICE

     The street address of the Company's registered office in the State of 
Delaware is 1013 Centre Road, Wilmington, New Castle County, Delaware 19805, and
the name of its registered agent at such address is Corporation Service 
Company.

                                  ARTICLE V.

                             ELECTION OF DIRECTORS

     A.   The business and affairs of the Company shall be conducted and managed
by, or under the direction of, the Company's Board of Directors (the "Board"). 
The total number of directors constituting the entire Board shall be fixed and 
may be altered from time to time by or pursuant to a resolution passed by the 
Board.

     B.   The Board shall be divided into three classes, Class A, Class B, and 
Class C. Such classes shall be as nearly equal in number of directors as 
possible. Each director shall serve for a term expiring at the third annual 
meeting following the annual meeting at which such director was elected; 
provided, however, that the directors first elected to Class A shall serve for 
an initial term expiring at the annual meeting following the end of the 
Company's 1996 fiscal year, the directors first elected to Class B shall serve 
for an initial term expiring at the second annual meeting next following the end
of the Company's 1996 fiscal year, and the directors first elected to Class C 
shall serve for an initial term expiring at the third annual meeting next 
following the end of the Company's 1996 fiscal year. The foregoing 
notwithstanding, except as otherwise provided in this Certificate or any 
resolution or resolutions of the Board designating a series of Preferred Stock, 
directors who are elected at an annual meeting of stockholders, and directors 
elected in the interim to fill vacancies and newly created directorships, shall 
hold office for the

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term for which elected and until their successors are elected and qualified or 
until their earlier death, resignation or removal. Whenever the holders of any 
class or classes of stock or any series thereof shall be entitled to elect one 
or more directors pursuant to any resolution or resolutions of the Board 
designating a series of Preferred Stock, and except as otherwise provided herein
or therein, vacancies and newly created directorships of such class or classes 
or series thereof may be filled by a majority of the directors elected by such
class or classes or series thereof then in office, by a sole remaining director
so elected or by the unanimous written consent or the affirmative vote of a
majority of the outstanding shares of such class or classes or series entitled
to elect such director or directors.

     C.   Except as otherwise provided for herein, newly created directorships 
resulting from any increase in the authorized number of directors, and any 
vacancies on the Board resulting from death, resignation, disqualification, 
removal or other cause, may be filled only by the affirmative vote of a majority
of the remaining directors then in office, even though less than a quorum of the
Board. Any director elected in accordance with the preceding sentence shall hold
office for the remainder of the full term of the newly created directorship or 
for the directorship in which the vacancy occurred, and until such director's 
successor shall have been duly elected and qualified, subject to his earlier 
death, disqualification, resignation or removal. Subject to the provisions of 
this Certificate, no decrease in the number of directors constituting the Board 
shall shorten the term of any incumbent director.

     D.   Except as otherwise provided in any resolution or resolutions of the
Board designating a series of Preferred Stock, any director may be removed from
office only by the affirmative vote of the holders of 66 2/3% or more of the
combined voting power of the then-outstanding shares of capital stock of the
Company entitled to vote at a meeting of stockholders called for that purpose,
voting together as a single class.

                                  ARTICLE VI.

                           MEETINGS OF STOCKHOLDERS

     A.   Meetings of stockholders of the Company ("Stockholder Meetings") may 
be held within or without the State of Delaware, as the Bylaws may provide. 
Except as otherwise provided in any resolution or resolutions of the Board 
designating a series of Preferred Stock, special Stockholder Meetings may be 
called only by (i) the President of the Company or (ii) the Board pursuant to a 
resolution adopted by a majority of the then-authorized number of directors of 
the Company. Special Stockholder Meetings may not be called by any other person 
or persons or in any other manner. Elections of directors need not be by written
ballot unless the Bylaws of the Company (the "Bylaws") shall so provide.

     B.   In addition to the powers conferred on the Board by this Certificate 
and by the Delaware General Corporation Law, and without limiting the generality
thereof, the Board is specifically authorized from time to time, by resolution 
of the Board without additional authorization by the stockholders of the 
Company, to adopt, amend or repeal the Bylaws, in such form and with such terms 
as the Board may determine, including, without limiting the generality of the 
foregoing, Bylaws relating to (i) regulation of the procedure for submission by 
stockholders

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of nominations of persons to be elected to the Board, (ii) regulation of the 
attendance at annual or special Stockholder Meetings by persons other than 
holders of record or their proxies, and (iii) regulation of the business that 
may properly be brought by a stockholder of the Company before an annual or 
special meeting of stockholders of the Company.

                                 ARTICLE VII.

                              STOCKHOLDER CONSENT

     Except as otherwise provided in any resolution or resolutions of the Board 
designating a series of Preferred Stock, no action that is required or permitted
to be taken by the stockholders of the Company at any annual or special meeting 
of stockholders may be effected by written consent of stockholders in lieu of a 
meeting of stockholders, unless the action to be effected by written consent of 
stockholders and the taking of such action by such written consent have 
expressly been approved in advance by the Board.

                                 ARTICLE VIII.

                            LIMITATION OF LIABILITY

     A director of the Company shall not be personally liable to the Company or 
its stockholders for monetary damages for breach of fiduciary duty as a 
director; provided, however, that this Article shall not eliminate or limit the 
liability of a director: (i) for any breach of the director's duty of loyalty to
the Company or stockholders, (ii) for acts or 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 the date of filing
of this Certificate to authorize corporate action further limiting or 
eliminating the personal liability of a director, then the liability of the 
directors of the Company shall be limited or eliminated to the fullest extent 
permitted by the Delaware General Corporation Law, as so amended. Any repeal or 
modification of this Article by the stockholders of the Company or otherwise 
shall not adversely affect any right or protection of a director of the Company 
existing at the time of such repeal or modification.

                                  ARTICLE IX.

                                  SECTION 203

     The Company shall be governed by Section 203 of the Delaware General 
Corporation Law.

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                                  ARTICLE X.

                                INDEMNIFICATION

     The Company shall indemnify each director and officer of the Company who 
may be indemnified, to the fullest extent permitted by Section 145 of the 
Delaware General Corporation Law ("Section 145"), as it may be amended from time
to time, in each and every situation where the Company is obligated to make such
indemnification pursuant to Section 145. In addition, the Company shall 
indemnify each of the Company's directors and officers in each and every 
situation where, under Section 145, the Company is not obligated, but is 
permitted or empowered, to make such indemnification. The Company may, in the 
sole discretion of the Board, indemnify any other person who may be indemnified 
pursuant to Section 145 to the extent the Board deems advisable, as permitted by
such section. The Company shall promptly make or cause to be made any 
determination which Section 145 requires.

                                  ARTICLE XI.

                       AMENDMENT OF CORPORATE DOCUMENTS

     A.   Certificate. Whenever any vote of the holders of voting shares of 
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capital stock of the Company is required by law to amend, repeal or rescind any 
provision of this Certificate, then in addition to any affirmative vote required
by applicable law and in addition to any vote of the holders of any series of 
Preferred Stock, as provided in any resolution or resolutions of the Board 
designating a series of Preferred Stock, such alteration, amendment, repeal or 
rescission (a "Change") of any provision of this Certificate must be approved by
at least a majority of the then-authorized number of directors and by the
affirmative vote of the holders of at least a majority of the combined voting
power of the then-outstanding voting shares of capital stock of the Company,
voting together as a single class; provided, however, that if any such Change
relates to Articles III, V, VI, VII, VIII, IX, X or to this Article XI, such
Change must also be approved by the affirmative vote of the holders of at least
662/3% of the combined voting power of the then-outstanding voting shares of
capital stock of the Company, voting together as a single class; provided
further, however, that the vote(s) required by the immediately preceding clause
shall not be required if such Change has been first approved by at least two-
thirds of the then-authorized number of directors.

          Subject to the provisions hereof, the Company reserves the right at 
any time, and from time to time, to amend, alter, repeal or rescind any 
provision contained in this Certificate in the manner now or hereafter 
prescribed by law, and other provisions authorized by the laws of the State of 
Delaware at the time in force may be added or inserted, in the manner now or 
hereafter prescribed by law; and all rights, preferences and privileges of 
whatsoever nature conferred upon stockholders, directors or any other persons 
whomsoever by and pursuant to this Certificate in its present form or as 
hereafter amended are granted subject to the rights reserved in this article.

     B.   Bylaws. In addition to any affirmative vote required by law, any 
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Change of the Bylaws may be adopted either (i) by the Board by the affirmative 
vote of at least a majority of

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the then-authorized number of directors, or (ii) by the stockholders by the 
affirmative vote of the holders of at least 662/3% of the combined voting power
of the then-outstanding voting shares of capital stock of the Company, voting 
together as a single class.

                                  ARTICLE XII.

                                   EXISTENCE

     The Company is to have perpetual existence.

                                 ARTICLE XIII.

                                RELATED PARTIES

     A.   No contract or transaction between the Company and one or more of its 
directors or officers, or between the Company and any other corporation, 
partnership, association, or other organization in which one or more of its 
directors or officers, are directors or officers, or have a financial interest, 
shall be void or voidable solely for this reason, or solely because the director
or officer is present at or participates in the meeting of the Board or 
committee which authorizes the contract or transaction, or solely because his or
their votes are counted for such purpose, if:

          (1)  The material facts as to his relationship or interest and as to 
     the contract or transaction are disclosed or are known to the Board or the 
     committee, and the Board or committee in good faith authorizes the contract
     or transaction by the affirmative votes of a majority of the disinterested
     directors, even though the disinterested directors be less than a quorum;
     or

          (2)  The material facts as to his relationship or interest and as to 
     the contract or transaction are disclosed or are known to the stockholders 
     entitled to vote thereon, and the contract or transaction is specifically 
     approved in good faith by a vote of the stockholders; or

          (3)  The contract or transaction is fair as to the Company as of the 
     time it is authorized, approved or ratified, by the Board, a committee or
     the stockholders.

     B.   Common or interested directors may be counted in determining the 
presence of a quorum at a meeting of the Board or of a committee which 
authorizes the contract or transaction.

                                 ARTICLE XIV.

                                 INCORPORATOR

     The name and mailing address of the incorporator of the Company is:

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          Matthew R. Bair, Esq.
          Akin, Grump, Strauss, Hauer & Feld, L.L.P.
          1500 NationsBank Plaza
          300 Covent Street
          San Antonio, Texas 78205

     IN WITNESS WHEREOF, this Certificate of Incorporation has been signed under
the seal of the Company on June 7, 1996.


                                               /s/ MATT BAIR
                                        _____________________________________
                                                   Matt Bair

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