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                                                                   EXHIBIT 10.1


                            PAGEMART WIRELESS, INC.

               FOURTH AMENDED AND RESTATED 1991 STOCK OPTION PLAN


                                   ARTICLE I

                               GENERAL PROVISIONS


       1.     PURPOSE

       The purpose of the PageMart Wireless, Inc. Fourth Amended and Restated
1991 Stock Option Plan (the "Plan") is  to strengthen PageMart Wireless, Inc.,
a Delaware corporation (the "Corporation"), by providing eligible individuals
who are responsible for the management, growth and financial success of the
Corporation or who otherwise render valuable services to the Corporation with
the opportunity to acquire a proprietary interest, or increase their
proprietary interest, in the Corporation and thereby providing a means of
attracting competent personnel and encouraging them to remain in the service of
the Corporation.

       2.     ADMINISTRATION OF THIS PLAN

        This Plan shall be administered by the Stock Option Committee of the
Board (the "Committee") which shall be comprised of two (2) or more directors,
each of whom shall be a "non-employee director," as defined in Rule 16b-3,
promulgated under the Securities Exchange Act of 1934, as amended (the
"Exchange Act").  The Committee shall have full power and authority (subject to
the provisions of this Plan) to establish such rules and regulations as it may
deem appropriate for the proper Plan administration and to construe the terms
of and make such determinations under, and issue such interpretations of, this
Plan and any outstanding option grants as it may deem necessary or advisable.
Decisions of the Committee shall be final and binding on all parties who have
an interest in this Plan or any outstanding option.

       3.     PERSONS ELIGIBLE TO RECEIVE OPTION GRANTS

              (a)    The persons eligible to receive option grants pursuant to
       this Plan ("Optionees") are limited to the following:

                     (i)    key employees (including officers and directors) of
              the Corporation (or its Parent or Subsidiary (as such terms are
              hereinafter defined) corporations) who render services which
              contribute to the success and growth of the Corporation (or its
              Parent or Subsidiary corporations) or which may reasonably be
              anticipated to contribute to the future success and growth of the
              Corporation (or its Parent or Subsidiary corporations); and

                     (ii)   the non-employee members of the Board (as such term
              is hereinafter defined) or the non-employee members of the board
              of directors of any Parent or Subsidiary corporations.
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              (b)    The Committee shall have full authority to determine, with
       respect to the option grants made under this Plan, which eligible
       individuals are to receive option grants, the number of shares to be
       covered by each such grant, the status of the granted option as either
       an Incentive Option or a Non-Statutory Option (as such terms are
       hereinafter defined), the time or times at which each granted option is
       to become exercisable and the maximum term for which the option may
       remain outstanding.

       4.     STOCK SUBJECT TO THIS PLAN

              (a)    The stock issuable under this Plan shall be shares of the
       Corporation's authorized but unissued or reacquired Class A convertible
       common stock, par value $.0001 per share ("Common Stock").  The maximum
       number of shares which may be issued over the term of this Plan shall
       not exceed 4,550,000 shares.  However, any shares of Common Stock issued
       under the Corporation's Third Amended and Restated 1991 Stock Issuance
       Plan will reduce, on a share-for-share basis, the number of shares
       issuable under this Plan.  The total number of shares issuable in the
       aggregate under this Plan and the Third Amended and Restated 1991 Stock
       Issuance Plan shall be subject to adjustment from time to time in
       accordance with the provisions of Section 4(c) of this Article I.

              (b)    Shares subject to (i) the portion of one or more
       outstanding options which are not exercised prior to expiration or
       termination and (ii) outstanding options cancelled in accordance with
       the cancellation-regrant provisions of Section 5 of Article II will be
       available for subsequent option grants under this Plan.  The shares
       which shall not be available for subsequent option grants under this
       Plan include (A) shares subject to an option  surrendered under this
       Plan in connection with a Change in  Control (as such term is
       hereinafter defined) and (B) shares issued pursuant to the exercise of
       an option (whether as vested or unvested shares) which are repurchased
       by the Corporation.

              (c)    In the event that the Committee shall determine that any
       dividend or other distribution (whether in the form of shares of Common
       Stock or other securities), recapitalization, stock split, reverse stock
       split, reorganization, merger, consolidation, split-up, spin-off,
       combination, repurchase or exchange of securities of the Corporation, or
       other similar corporate transaction or event affects the benefits or
       potential benefits intended to be made available under this Plan such
       that an adjustment is determined by the Committee to be appropriate in
       order to prevent dilution or enlargement of the benefits or potential
       benefits intended to be made available under this Plan, then the
       Committee may, in such manner as it may deem equitable, adjust any or
       all of (i) the number of shares of Common Stock subject to this Plan and
       which thereafter may be made the subject of options under this Plan,
       (ii) the number of shares of Common Stock subject to outstanding
       options, (iii) the nature of the consideration (including, without
       limitation, other securities of the Corporation, securities of another
       entity and/or other property) to be received upon exercise of an option
       and/or (iv) the grant, purchase or exercise price with respect to any
       option, or, if deemed appropriate, make provisions for a cash payment to
       the holder of an outstanding option; provided, however, in each case,
       that with respect to Incentive Options no such adjustment shall be
       authorized to the extent that such




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       adjustment would cause this Plan to violate Section 422(b)(1) or 424(a)
       of the Code (as such term is hereinafter defined) or any successor
       provisions thereto; and provided further, however, that the number of
       shares of Common Stock subject to any option payable or denominated in
       shares of Common Stock shall always be a whole number.  Notwithstanding
       the foregoing, Non-Statutory Options shall be subject to only such
       adjustment as shall be necessary to maintain the proportionate interest
       of the Optionee and preserve, without exceeding, the value of such
       option.

              (d)    Common Stock issuable under this Plan may be subject to
       such restrictions as may be determined by the Committee, including,
       without limitation, restrictions on transfer, repurchase rights and
       other restrictions.

       5.     DEFINITIONS

              The following definitional provisions shall be in effect for all
       purposes under this Plan:

              (a)    Board  means  the  board  of  directors  of  PageMart
       Wireless, Inc.

              (b)    Change in Control means the acquisition of fifty percent
       (50%) or more of the Corporation's outstanding voting stock pursuant to
       a tender or exchange offer made by a person or group of related persons
       (other than the Corporation or a person that directly or indirectly
       controls, is controlled by or is under common control with the
       Corporation) which the Board does not recommend to the stockholders.

              (c)    Code means the Internal Revenue Code of 1986, as amended.

              (d)    Corporation means PageMart Wireless, Inc., a Delaware
       corporation.

              (e)    Corporate Transaction  means one or more of the following
       stockholder-approved transactions:

                     (i)    a merger or consolidation in which the Corporation
              is not the surviving entity, provided securities possessing fifty
              percent (50%) or more of the total combined voting power of the
              Corporation's outstanding voting securities are transferred to a
              person or persons different from those who held such securities
              immediately prior to such transaction,

                     (ii)   the sale, transfer or other disposition of all or
              substantially all of the assets of the Corporation other than in
              the ordinary course of business, or

                     (iii)  any reverse merger in which the Corporation is the
              surviving entity but in which securities possessing fifty percent
              (50%) or more of the total combined voting power of the
              Corporation's outstanding voting securities are





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              transferred to person or persons different from those who held
              such securities immediately prior to such merger.

       In no event shall any merger, consolidation or other reorganization
       involving the Corporation be deemed to constitute a Corporate
       Transaction if the primary purpose of such transaction is either to
       change the State in which the Corporation is incorporated or to create a
       holding-company structure whereby the Corporation's stockholders of
       record become the stockholders of the holding company.

              (f)    Employee means an individual who is in the employ of the
       Corporation or one or more Parent or Subsidiary corporations.  An
       Optionee shall be considered to be an Employee for so long as such
       individual remains in the employ of the Corporation or one or more
       Parent or Subsidiary corporations, subject to the control and direction
       of the employer entity as to both the work to be performed and the
       manner and method of performance.

              (g)    Exercise Date shall be the date on which both (i) written
       notice of the exercise of an outstanding option under this Plan and (ii)
       payment of the option price are delivered to the Corporation.

              (h)    Fair Market Value of a share of Common Stock on any
       relevant date shall be determined in accordance with the following
       provisions:

                     (i)    If the Common Stock is not at the time listed or
              admitted to trading on any national securities exchange but is
              traded in the over-the-counter market, the Fair Market Value
              shall be the mean between the highest bid and the lowest asked
              prices (or, if such information is available, the closing sales
              price) per share of Common Stock on the date in question in the
              over-the-counter market, as such prices are reported by the
              National Association of Securities Dealers through its Nasdaq
              National Market System or any successor system. If there are no
              reported bid and asked prices (or closing sales price) for the
              Common Stock on the date in question, then the mean between the
              highest bid and lowest asked prices (or closing sales price) on
              the last preceding date for which such quotations exist shall be
              determinative of Fair Market Value.

                     (ii)   If the Common Stock is at the time listed or
              admitted to trading on any national securities exchange, then the
              Fair Market Value shall be the closing sales price per share of
              Common Stock on the date in question on the national securities
              exchange determined by the Committee to be the primary market for
              the Common Stock, as such price is officially quoted in the
              composite tape of transactions on such exchange.  If there is no
              reported sale of Common Stock on such exchange on the date in
              question, then the fair market value shall be the closing sales
              price on the exchange on the last preceding date for which such
              quotation exists.





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                     (iii)  If the Common Stock is at the time neither listed
              nor admitted to trading on any national securities exchange nor
              traded in the over-the-counter market, or if the Committee
              determines that the valuation provisions of subparagraphs (i) and
              (ii) above will not result in a true and accurate valuation of
              the Common Stock, then the Fair Market Value shall be determined
              by the Committee after taking into account such factors as the
              Committee shall deem appropriate under the circumstances.

              (i)    Incentive Option means an incentive stock option which
       satisfies the requirements of Section 422 of the Code.

              (j)    Non-Statutory Option means an option that does not meet
       (whether at the time of the grant of such option or subsequently) the
       statutory requirements prescribed for an Incentive Option.

              (k)    Notice of Grant means written notification (in
       substantially the form attached hereto as EXHIBIT B) of the grant of an
       option pursuant to this Plan.

              (l)    Parent corporation means any corporation  which, directly
       or indirectly, owns, at the time of the determination, stock possessing
       fifty percent (50%) or more of the total combined voting power of all
       classes of stock of the Corporation .

              (m)    Permanent Disability shall have the meaning set forth in
       Section 22(e)(3) of the Code, or any successor provision thereto.

              (n)    Plan  means  this  Fourth Amended and Restated 1991  Stock
       Option Plan of the Corporation.

              (o)    Service means the performance of services for the
       Corporation or one or more Parent or Subsidiary corporations by an
       individual in the capacity of an Employee or a non-employee member of
       the Board or the board of directors of such Parent or Subsidiary
       corporations, unless a different meaning is specified in the Stock
       Option Agreement.  An Optionee shall be deemed to remain in Service for
       so long as such individual renders services to the Corporation or any
       Parent or Subsidiary corporation on a periodic basis in the capacity of
       an Employee or a non-employee member of the Board or the board of
       directors of such Parent or Subsidiary corporation.

              (p)    Stock Option Agreement means a stock option agreement, in
       substantially the form attached hereto as EXHIBIT A and incorporated
       herein by reference (the "Stock Option Agreement"), incorporating any
       repurchase rights or first refusal rights retained by the Corporation
       with respect to the Common Stock purchased under an option.

              (q)    Subsidiary corporation means any corporation of which the
       Corporation, directly or indirectly, owns, at the time of the
       determination, stock possessing fifty percent





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       (50%) or more of the total combined voting power of all classes of stock
       of the corporation in question.

              (r)    10% Stockholder means the owner of stock (as determined
       under  Section 424(d) of the Code) possessing 10% or more of the total
       combined voting power and value of all classes of stock of the
       Corporation or any Parent or Subsidiary corporation.


                                   ARTICLE II

                                 OPTION GRANTS

       1.     TERMS AND CONDITIONS OF OPTIONS

       Options granted pursuant to this Plan shall be authorized by action of
the Committee and may, at the discretion of the Committee, be either Incentive
Options or Non-Statutory Options.  Each granted option shall be evidenced by a
Stock Option Agreement and a Notice of Grant; provided, however, that each
Stock Option Agreement shall comply with and incorporate the terms and
conditions specified below.  Each Stock Option Agreement evidencing an
Incentive Option shall, in addition, be subject to the applicable provisions of
Section 2 of this Article II.

              (a)    Option Price.

                     (i)    The option price per share shall be fixed by the
              Committee; provided, however, that in no event shall the option
              price per share be less than eighty-five percent (85%) for
              Non-Statutory Options or less than one hundred percent (100%) for
              Incentive Options of the Fair Market Value of a share of Common
              Stock on the date of the option grant.

                     (ii)   If the individual to whom the option is granted is
              at the time a 10% Stockholder and the option granted is an
              Incentive Option, then the option price per share shall not be
              less than one hundred ten percent (110%) of the Fair Market Value
              of the Common Stock on the grant date.

                     (iii)  The option price shall be payable in such form and
              by such method as shall be determined by the Committee,
              including, without limitation, cash (subject to the provisions of
              Article III, Section 1), shares of Common Stock, other securities
              or other property or any combination thereof, having a fair
              market value (as determined in accordance with the terms of this
              Plan in the case of Common Stock and in all other cases by such
              methods or procedures as shall be authorized by the Committee) on
              the Exercise Date equal to the relevant exercise price (including
              payment in accordance with a cashless exercise program under
              which, if so instructed by the person exercising the option,
              shares of Common Stock may be issued directly to such person's
              broker or dealer upon receipt of the purchase price in cash from
              the broker or dealer).





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              (b)    Term and Exercise of Options.  Each option granted under
       this Plan shall be exercisable at such time or times, during such
       period, and for such number of shares of Common Stock as shall be
       determined by the Committee and set forth in the Stock Option Agreement
       evidencing such option.  However, no option granted under this Plan
       shall have a term in excess of ten (10) years from the grant date, and
       no Incentive Option granted to a 10% Stockholder shall have a term in
       excess of five (5) years from the grant date.

              (c)    Nontransferability of Options.  During the lifetime of the
       Optionee, the option shall be exercisable only by the Optionee or by the
       Optionee's duly appointed guardian or personal representative and shall
       not be assignable or transferable by the Optionee otherwise than by will
       or by the laws of descent and distribution following the Optionee's
       death.

              (d)    Termination of Service.

                     (i)    Should an Optionee cease to remain in Service for
              any reason other than (i) Permanent Disability, (ii) death or
              (iii) for Cause (as such term is hereinafter defined), an option
              (to the extent otherwise exercisable on the date of such
              termination) shall be exercisable by the Optionee at any time
              prior to the expiration date of the option (except as otherwise
              provided pursuant to Section 6 of this Article II) or within
              three (3) months after the date of such termination, whichever is
              the shorter period.

                     (ii)   If an Optionee's Service ceases by reason of the
              Optionee's Permanent Disability, an option (to the extent
              otherwise exercisable on the date of such termination by reason
              of Permanent Disability) shall remain exercisable by the Optionee
              at any time prior to the expiration date of the option (except as
              otherwise provided pursuant to Section 6 of this Article II) or
              within twelve (12) months after the date of such termination,
              whichever is the shorter period.

                     (iii)  If an Optionee's Service ceases as a result of
              death, an option (to the extent otherwise exercisable on the date
              of the death of such Optionee) shall remain exercisable  by the
              person or persons entitled to do so under the Optionee's will,
              or, if the Optionee shall fail to make testamentary disposition
              of said option or shall die intestate, by the Optionee's legal
              representative or representatives, at any time prior to the
              expiration date of the option (except as otherwise provided
              pursuant to Section 6 of this Article II) or within twelve (12)
              months after the date of such death, whichever is the shorter
              period.

                     (iv)   If the Optionee's Service ceases as a result of
              termination for Cause (as hereinafter defined), any then
              outstanding options of such Optionee shall automatically
              terminate as of the termination date.  As used herein,
              termination for "Cause" shall mean termination upon the
              occurrence of one or more of the following events:





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                            (A)    The Optionee's failure to substantially
                     perform his duties with the Corporation or any Parent or
                     Subsidiary corporation as determined by the Committee in
                     its sole discretion following receipt by the Optionee of
                     written notice of such failure and the Optionee's failure
                     to remedy such failure within thirty (30) days after
                     receipt of such notice (other than failure from his
                     incapacity during physical or mental illness);

                            (B)    The Optionee's willful failure or refusal to
                     perform specific directives of the Board, which directives
                     are consistent with the scope and nature of the Optionee's
                     duties and responsibilities, and which are not remedied by
                     the Optionee within thirty (30) days after being notified
                     in writing of his failure by the Board;

                            (C)    The Optionee's conviction of a felony; or

                            (D)    A breach of the Optionee's fiduciary duty to
                     the Corporation or any Parent or Subsidiary corporation or
                     willful violation in the course of performing his duties
                     for the Corporation or any Parent or Subsidiary
                     corporation of any law, rule or regulation (other than
                     traffic violations or other minor offenses).  No act or
                     failure to act on the Optionee's part shall be considered
                     willful unless done or omitted to be done in bad faith and
                     without reasonable belief that the action or omission was
                     in the best interest of the Corporation or any Parent or
                     Subsidiary corporation.

              (e)    Stockholder Rights.  No shares of Common Stock shall be
       issued until payment, as provided herein, therefor has been made.  An
       Optionee shall have none of the rights of a stockholder with respect to
       the Common Stock covered by an option until such Optionee shall have
       exercised the option and paid the option price.

       2.     INCENTIVE OPTIONS

       The terms and conditions specified below shall be applicable to all
Incentive Options granted under this Plan.  Incentive Options may only be
granted to individuals who are Employees.  Options which are specifically
designated as Non-Statutory Options when issued under this Plan shall not be
subject to such terms and conditions.

              (a)    Option Price.  The  option  price  per  share  of  the
       Common Stock subject to  an  Incentive  Option  shall  in  no  event  be
       less than one hundred percent (100%) of the Fair Market Value of a share
       of Common Stock on the grant date.

              (b)    Dollar Limitation.  The aggregate Fair Market Value
       (determined as of the respective date or dates of grant) of the Common
       Stock for which one or more options granted to any Employee under this
       Plan (or any other plan of the Corporation or any Parent or Subsidiary
       corporation) may for the first time become exercisable as incentive
       stock options under the Federal tax laws during any one calendar year
       shall not exceed





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       the sum of One Hundred Thousand Dollars ($100,000). To the extent the
       Employee holds two or more such options which become exercisable for the
       first time in the same calendar year, the foregoing limitation on the
       exercisability thereof as Incentive Options under the Federal tax laws
       shall be applied on the basis of the order in which such options are
       granted.  In the event the limits of this Section 2(b) would otherwise
       be exceeded, the Optionee may still exercise the options, but such
       option, to the extent of such excess, shall be deemed to be a
       Non-Statutory Option.  Except as modified by the preceding provisions of
       this Section 2, all the provisions of this Plan shall be applicable to
       the Incentive Options granted hereunder.

       3.     LIMITED SURRENDER RIGHTS

              (a)    Should a Change in Control occur at a time when the
       Corporation's outstanding capital stock is registered under Section 12
       of the Exchange Act, then each Optionee who is at the time an officer or
       director of the Corporation subject to the short-swing profit
       restrictions of the Federal securities laws shall have the right to
       surrender any or all options held by such individual under this Plan, to
       the extent such options have been outstanding for at least six (6)
       months and are at the time exercisable for vested shares.  In return for
       each surrendered option, the officer or director shall receive an
       appreciation distribution from the Corporation in an amount equal to the
       excess of (i) the aggregate Acquisition Price (as such term is
       hereinafter defined) of the number of shares in which such individual is
       at the time vested under the surrendered option over (ii) the aggregate
       option price payable for such vested shares.  Such limited surrender
       right shall be exercisable for a period not to exceed thirty (30) days
       following the completion of the Change in Control.  Neither the approval
       of the Committee nor the consent of the Board shall be required for such
       surrender, and the distribution to which such Optionee shall become
       entitled upon the option surrender shall be made entirely in cash.

              (b)    The "Acquisition Price" per share of the vested Common
       Stock subject to the surrendered option shall be deemed to be equal to
       the greater of (i) the Fair Market Value per share on the date of
       surrender or (ii) the highest reported price per share paid in effecting
       the Change in Control of the Corporation's outstanding voting stock.
       However, if the surrendered option is an Incentive Option, then the
       Acquisition Price of the vested shares subject to the surrendered option
       shall not exceed the clause (i) value per share.

       4.     CORPORATE TRANSACTIONS

              (a)    In the event of any Corporate Transaction, each option
       outstanding under this Plan shall automatically accelerate so that each
       such option shall, immediately prior to the specified effective date for
       such Corporate Transaction, become fully exercisable with respect to the
       total number of shares of Common Stock at the time subject to such
       option and may be exercised for all or any portion of such shares.





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              (b)    Upon the consummation of the Corporate Transaction, each
       option outstanding under this Plan shall terminate and cease to be
       exercisable.

              (c)    The exercisability as incentive stock options under the
       Federal tax laws of any options accelerated in connection with the
       Corporate Transaction shall remain subject to the applicable dollar
       limitation of subsection 2(b) of this Article II.

              (d)    The grant of options under this Plan shall in no way
       affect the legal right of the Corporation to adjust, reclassify,
       reorganize or otherwise change its capital or business structure or to
       merge, consolidate, dissolve, liquidate or sell or transfer all or any
       part of its business or assets.

       5.     CANCELLATION AND NEW GRANT OF OPTIONS

       The Committee shall have the authority to effect, at any time and from
time to time, with the consent of the affected Optionees, the cancellation of
any or all outstanding options under this Plan and to grant in substitution
therefor new options under this Plan covering the same or different numbers of
shares of Common Stock but having an option price per share not less than
eighty-five percent (85%) of the Fair Market Value per share of Common Stock on
the new grant date (or one hundred percent (100%) of such Fair Market Value in
the case of an Incentive Option or, in the case of an Incentive Option held by
a 10% Stockholder, not less than one hundred and ten percent (110%) of such
Fair Market Value).

       6.     EXTENSION OF EXERCISE PERIOD

       The Committee shall have full power and authority  to  extend  (either
at  the  time  while  the  option  is granted or at any time while the option
remains outstanding) the period of time for which the option is to remain
exercisable following an Optionee's cessation of Service, from the limited
period set forth in the Stock Option Agreement to such greater period of time
as the Committee may deem appropriate under the circumstances.  In no event,
however, shall such option be exercisable after the specified expiration date
of the option term.


                                  ARTICLE III

                                 MISCELLANEOUS

       1.     LOANS

              (a)    The Committee may assist any Optionee (including an
       Optionee who is an officer or director of the Corporation) in the
       exercise of one or more options granted to such Optionee under this
       Plan, including the satisfaction of any Federal, State and local income
       and employment tax obligations arising therefrom, by





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                     (i)    authorizing the extension of a loan from the
              Corporation to such Optionee, or

                     (ii)   permitting the Optionee to pay the option price for
              the purchased Common Stock in installments over a period of
              years.

              (b)    The terms of any loan or installment method of payment
       (including the interest rate and terms of repayment) shall be
       established by the Committee in its sole discretion.  Loans or
       installment payments may be granted with or without security or
       collateral.  In all events the maximum credit available to each Optionee
       may not exceed the sum of (i) the aggregate option price or purchase
       price payable for the purchased shares (less the par value payable for
       the purchased shares) plus (ii) any Federal, State or local income and
       employment tax liability incurred by the Optionee in connection with
       such exercise.

              (c)    The Committee may, in its absolute discretion, determine
       that one or more loans extended under the financial assistance program
       shall be subject to forgiveness by the Corporation in whole or in part
       upon such terms and conditions as the Committee in its discretion deems
       appropriate.

       2.     AMENDMENT OF THIS PLAN AND AWARDS

              (a)    The Board shall have complete and exclusive power and
       authority to amend, modify, suspend, discontinue or terminate this Plan
       in any or all respects whatsoever.  However, no such amendment,
       modification, suspension, discontinuance or termination shall adversely
       affect the rights and obligations of an Optionee with respect to options
       at the time outstanding under this Plan, unless the Optionee consents
       thereto.  No option may be granted during any suspension of this Plan or
       after its termination.  In addition, the Board shall not, without the
       approval of the Corporation's stockholders, amend this Plan to (i)
       materially increase the maximum number of shares issuable under this
       Plan (except for permissible adjustments under Article I, Section 4(c)),
       (ii) change the minimum option price, (iii) increase the maximum terms
       for options granted hereunder, (iv) remove the administration of this
       Plan from the Committee, (v) materially increase the benefits accruing
       to individuals who participate in this Plan or (vi) materially modify
       the eligibility requirements for participation in this Plan.

              (b)    Options to purchase shares of Common Stock may be granted
       under this Plan which are in excess of the number of shares then
       available for issuance under this Plan, provided there is obtained Board
       approval of an amendment sufficiently increasing the number of shares of
       Common Stock available for issuance under this Plan prior to the actual
       option grant and stockholder approval of such amendment prior to the
       exercise of the option.  If such stockholder approval is not obtained
       within twelve (12) months after the date the amendment to this Plan is
       approved by the Board, then all options representing such excess shall
       terminate and cease to be exercisable.





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       3.     EFFECTIVE DATE AND TERM OF PLAN

              (a)    This Plan shall become effective when adopted by the
       Board.  All options previously granted under this Plan shall remain in
       full force and effect, subject to the terms of the Stock Option
       Agreements under which they were issued and this Plan.

              (b)    This Plan shall terminate upon the earlier of (i) August
       19, 2001 or (ii) the date on which all shares available for issuance
       under this Plan have been issued or cancelled pursuant to the exercise
       or surrender of options granted hereunder.  If the date of termination
       is determined under clause (i) above, then no options outstanding on
       such date shall be affected by the termination of this Plan, and such
       securities shall thereafter continue to have force and effect in
       accordance with the provisions of the Stock Option Agreements evidencing
       such options.

       4.     USE OF PROCEEDS

       Any cash proceeds received by the Corporation from the issuance of
shares of Common Stock under this Plan shall be used for general corporate
purposes.

       5.     CONTINUATION OF EMPLOYMENT

       Nothing contained in this Plan (or in any option granted pursuant to
this Plan) shall confer upon any Optionee any right to continue in the employ
of the Corporation or any Parent or Subsidiary corporation or constitute any
contract or agreement of employment or interfere in any way with the right of
the Corporation or any Parent or Subsidiary corporation to reduce any
Optionee's compensation from the rate in existence at the time of the granting
of an option or to terminate such Optionee's employment.  Nothing contained
herein or in any Stock Option Agreement shall affect any other contractual
rights of an Optionee.

       6.     WITHHOLDING

       The Corporation's obligation to deliver shares upon the exercise or
surrender of any options granted under this Plan shall be subject to the
satisfaction of all applicable Federal, State and local income and employment
tax withholding requirements.  The Corporation or any Parent or Subsidiary
corporation that employs any Optionee shall have the right to deduct any sums
that the Committee reasonably determines that Federal, State or local tax law
requires to be withheld with respect to the exercise of any option or as
otherwise may be required by those laws.  Neither the Corporation nor any
Parent or Subsidiary corporation shall be obligated to advise any Optionee of
the existence of the tax or the amount which the employer corporation will be
so required to withhold.  Upon the exercise of a Non-Statutory Option, if tax
withholding is required, an Optionee may, with the consent of the Committee,
have shares of Common Stock withheld ("Share Withholding") by the Corporation
from the shares otherwise to be received; provided, however, that if the
Optionee is subject to the provisions of Section 16 under the Exchange Act, no
Share Withholding shall be permitted unless such transaction complies with the
requirements of Rule 16b-3 promulgated under the Exchange Act.  The number of
shares so





                                      -12-
<PAGE>   13
withheld should have an aggregate Fair Market Value on the date of exercise
sufficient to satisfy the applicable withholding taxes.

       7.     REGULATORY APPROVALS

       The implementation of this Plan, the granting of any options hereunder
and the issuance of Common Stock upon the exercise or surrender of the option
grants made hereunder shall be subject to the Corporation's procurement of all
approvals and permits required by regulatory authorities having jurisdiction
over this Plan, the options granted under it and the Common Stock issued
pursuant to it.  Without limiting the generality of the foregoing, no options
granted hereunder may be exercised and no shares of Common Stock issuable upon
exercise of such options may be transferred unless and until the Committee
determines that such exercise/transfer will be made in compliance with all
applicable laws, rules and regulations, including, without limitation,
applicable securities laws, rules and regulations.  The Corporation does not
have any obligation to take any action to (i) register or qualify options or
shares of Common Stock pursuant to applicable laws or to perfect an exemption
from such registration/qualification requirements or (ii) list the shares of
Common Stock for trading on any stock exchange or automated transaction
reporting system.

       8.     GOVERNING LAW

       This Plan and the options issued hereunder shall be governed by, and
construed and enforced in accordance with, the laws of the State of Texas
applicable to contracts made and performed within that State.

       9.     COMPLIANCE WITH RULE 16B-3

       At such time and so long as the Corporation shall have a class of equity
securities registered under Section 12 of the Exchange Act, it is intended that
this Plan be applied and administered in compliance with Rule 16b-3.  If any
provision of this Plan would be in violation of Rule 16b-3 if applied as
written, such provision shall not have effect as written and shall be given
effect so as to comply with Rule 16b-3, as determined by the Committee.  The
Board is authorized to amend this Plan and to make any such modifications to
the Stock Option Agreements to comply with Rule 16b-3, as it may be amended
from time to time, and to make any other such amendments or modifications
deemed necessary or appropriate to better accomplish the purposes of this Plan
in light of any amendments made to Rule 16b-3.

       10.    NO LIABILITY FOR GOOD FAITH DETERMINATIONS

       Neither the members of the Board nor any member of the Committee shall
be liable for any action, failure to act, omission or determination taken or
made in good faith with respect to this Plan or any option granted under it.





                                      -13-
<PAGE>   14
       11.    OTHER BENEFITS

       Participation in this Plan shall not preclude the Optionee from
eligibility in any other stock option plan of the Company or any Parent or
Subsidiary corporation or any old age, benefit, insurance, pension, profit
sharing, retirement, bonus or other extra compensation plans which the
Corporation or any Parent or Subsidiary corporation has adopted, or may, at any
time, adopt for the benefit of its employees.

       12.    EXECUTION OF RECEIPTS AND RELEASES

       Any payment or any issuance or transfer of shares of Common Stock to an
Optionee, or to his legal representative, heir, legatee or distributee, in
accordance with the provisions hereof, shall, to the extent thereof, be in full
satisfaction of all claims of such persons hereunder.  The Committee may
require any Optionee, legal representative, heir, legatee or distributee, as a
condition precedent to such payment, to execute a release and receipt therefor
in such form as it shall determine.

       13.    PAYMENT OF EXPENSES

       All expenses incident to the administration, termination or performance
of this Plan, including, without limitation, legal and accounting fees, shall
be paid by the Corporation.  All expenses incurred by an Optionee shall be paid
by such Optionee.

       14.    CORPORATE RECORDS

       Records of the Corporation or any Parent or Subsidiary corporation
regarding the Optionee's period of employment, termination of employment and
the reason therefor, leaves of absence, re-employment and other matters shall
be conclusive for all purposes hereunder, unless determined by the Board to be
incorrect.





                                      -14-
<PAGE>   15
                                   EXHIBIT A

                             STOCK OPTION AGREEMENT





EXHIBIT A
<PAGE>   16
                                   EXHIBIT B

                        NOTICE OF GRANT OF STOCK OPTION





EXHIBIT B