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                                                                     Exhibit 4.4

                      EFFECTIVE DATE: _____________________



                                  STOCK OPTION
                                   GRANTED BY
                            SALIX TECHNOLOGIES, INC.
                                       TO
                                 EUGENE CARLOCK
                        (HEREINAFTER CALLED THE "HOLDER")

         For valuable consideration, the receipt of which is hereby
acknowledged, SALIX Technologies, Inc., a Delaware corporation (the "Company"),
hereby grants to the Holder the following option:

         SECTION 1. GRANT OF OPTION; VESTING. Subject to the terms and
conditions hereinafter set forth, the Holder is hereby given the right and
option to purchase from the Company at the option price of One Dollar ($1.00)
per share an aggregate of Seven Thousand Five Hundred (7,500) shares of the
Company's Common Stock, par value $0.01 ("Common Stock"), during the period and
in the manner hereinafter set forth. The Holder's rights to the option issued
hereunder shall vest at a rate of twenty-five percent (25%) per Phase completed
under that certain Agreement between Holder and the Company dated __________,
1997, such that, at the end of Phase 4, the Holder shall be 25% vested in his
options; at the end of Phase 5, the Holder shall be 50% vested in his options,
and so on until the end of Phase 7 when the Holder will be 100% vested in the
options granted hereunder.

         SECTION 2. EXERCISE OF OPTION. The options granted hereunder, which
have become vested, shall be exercisable only upon either of the following two
events: (a) the Company receives funding of at least Two Million Dollars
($2,000,000) from a venture capital source; or (b) the Company participates in
an initial public offering of its Common Stock (each of the foregoing, a
"Triggering Event"). In order to exercise the options granted hereunder, Holder
shall notify the Company in writing, which notice shall specify the number of
shares of Common Stock the Holder then desires to purchase. Payment for the
shares of Common Stock purchased pursuant to the exercise of options shall be
made by either cash, certified or bank check or postal money order payable to
the order of the Company for an amount equal to the option price of such shares.

         As promptly as practicable after receipt of the option notice from the
Holder, the Company and the Holder shall agree upon a mutually convenient time
to exchange payment and the investment letter referred to in Section 3, and the
certificate(s) for the number of shares with respect to which the option has
been exercised, registered in the name of the Holder. Such exchange shall take
place at the principal offices of the Company.

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         SECTION 3. CONDITIONS AND LIMITATIONS. As a condition precedent to any
exercise of this option, the Holder shall deliver to the Company an investment
letter in form and substance satisfactory to the Company and its counsel which
shall contain among other things a statement in writing to the following effects
(to the extent then applicable): (a) that the option is then being exercised for
the account of the Holder and only with a view to investment in, and not for, in
connection with or with a view to the disposition of, the shares with respect to
which the option is then being exercised; (b) that the Holder acknowledges that
the restrictions on transfer of the Common Stock of the Company set forth in
this Option Agreement shall apply to such shares; (c) if applicable, that the
Holder understands that there is no assurance that the Company will ever become
a reporting company under the Securities Exchange Act of 1934 and that the
Company has no obligation to the Holder to do so; (d) that the Holder and
Holder's representatives have fully investigated the Company and the business
and financial conditions concerning it and have knowledge of the Company's then
current corporate activities and financial condition; and (e) that the Holder
believes that the nature and amount of the shares being purchased are consistent
with Holder's investment objectives, abilities and resources. The restrictions
imposed by this Section and any investment representation made pursuant to this
Section shall be inoperative upon the registration with the Securities and
Exchange Commission of the stock subject to the options granted hereunder or
acquired through the exercise of options granted hereunder.

         SECTION 4. DILUTION OR OTHER AGREEMENT. The number of shares of Common
Stock reserved for issuance upon the exercise of these options and the option
price for these options shall be proportionately adjusted for any increase or
decrease in the number of issued shares of Common Stock resulting from a
subdivision or combination of shares or the payment of a stock dividend in
shares of Common Stock to holders of outstanding shares of Common Stock or any
other increase or decrease in the number of shares of Common Stock outstanding
effected without the receipt of consideration by the Company. Any adjustment
pursuant to this Section 4, may provide, in the Board's discretion, for the
elimination without payment therefor of any fractional shares that might
otherwise become subject to this option, but shall not otherwise diminish the
then value of the options granted hereunder.

         Subject to any required action by the stockholders, if the Company
shall be the surviving corporation in any merger or consolidation in which the
stockholders of the Company retain their Common Stock, this option shall pertain
to and apply to the securities to which the Holder of the number of shares of
Common Stock subject to options would have been entitled. A dissolution or
liquidation of the Company or a merger or consolidation in which the Company is
not the surviving Company or a merger or consolidation of the Company in which
the stockholders of the Company surrender their Common Stock shall cause these
options to terminate upon payment of the difference, if any, between the option
price per share of each share covered by this option and the Fair Market Value
of such stock on the date of dissolution, liquidation, merger or consolidation,
as if the options had been exercised on the date of such dissolution,
liquidation, merger or consolidation.

         To the extent that the foregoing adjustments relate to stock or
securities of the Company, such adjustments shall be made by the Board of
Directors whose determination in that respect shall be final.


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         Notwithstanding anything contained herein to the contrary, the
existence of this Option Agreement and the options granted pursuant hereto shall
not affect in any way the right or power of the Company to make or authorize any
adjustment, reclassification, reorganization or other change in its capital or
business structure, any merger or consolidation of the Company, any issue of
debt or equity securities having preferences or priorities as to the Common
Stock or the rights thereof, the dissolution or liquidation of the Company, any
sale or transfer of all or any part of its business or assets or any other
corporate act or proceeding.

         Except as hereinbefore expressly provided in this Section 4, the Holder
shall have no rights by reason of any subdivision or consolidation of shares of
stock of any class or the payment of any stock dividend or any other increase or
decrease in the number of shares of stock of any class or by reason of any
dissolution, liquidation, merger, or consolidation or spin-off of assets or
stock of another corporation.

         SECTION 5. RIGHTS OF HOLDER. Holder shall have no rights as a
stockholder with respect to any shares covered by these options until the date
of issuance of a stock certificate to him for such shares. No adjustment shall
be made for dividends (ordinary or extraordinary, whether in cash, securities or
other property) or distributions or other rights for which the record date is
prior to the date such stock certificate is issued, except as provided in
Section 4 hereof.

         Nothing herein contained shall impose any obligation upon the Holder to
exercise the options.

         The Company makes no representation as to the tax treatment to the
Holder upon receipt or exercise of the options or sale or other disposition of
the shares covered by the options. The Company recommends that the Holder
consult his personal tax advisor with regard to such tax matters.

         At all times while any portion of the options is outstanding, the
Company shall: reserve and keep available, out of shares of its authorized and
unissued stock or reacquired shares, a sufficient number of shares of its Common
Stock to satisfy the requirements of the options granted hereunder; comply with
the terms of these options promptly upon exercise of option rights; and pay all
fees or expenses necessarily incurred by the Company in connection with the
issuance and delivery of shares pursuant to the exercise of options hereunder.

         SECTION 6. TRANSFER, CERTAIN LIMITATIONS AND TERMINATION. During the
lifetime of the Holder, this option is exercisable only by the Holder and shall
not be assignable or transferable other than by will or the laws of descent and
distribution; provided, however, that only vested options may pass by will or
the laws of descent, and, provided, further, that the Holder agrees that in the
event of Holder's death, the vested options shall be devised, in the aggregate,
to only one heir or successor entity. Upon any attempt so to transfer, assign,
pledge, hypothecate, or otherwise dispose of the option, or of any right or
privilege conferred thereby, contrary to the provisions hereof, or upon the levy
of any attachment or similar process upon such option, right or privilege, the
option and such rights and privileges shall immediately become null and void.

         If the Holder shall die and shall not have exercised this option, the
Company shall have the right, exercisable within ninety (90) days after Holder's
death by written notice to the



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Holder's personal representative, to cancel this Option Agreement and terminate
the options granted hereunder, whether or not vested, provided the Company pays
to the Holder's estate an amount equal to One Dollar ($1.00) per share for each
share for which this option has vested. The portion of this option that has not
vested upon the death of the Holder shall automatically terminate without any
compensation to the Holder's estate. If the Company does not elect to exercise
its right hereunder to cancel the options within said 90-day period, then the
vested options may be distributed to the Holder's estate and may be exercised,
upon a Triggering Event, by the Holder's executors or administrators or by any
person or persons who shall have acquired the options directly from the Holder
by bequest or inheritance (provided such options have not otherwise expired).
Notwithstanding anything contained in this Option Agreement to the contrary, if
the Holder should die prior to the exercise of the options granted hereunder,
this Option Agreement and the options granted hereunder shall expire one (1)
year after the date of Holder's death. In the event vested options are
transferred to the Holder's executor or administrator, to a distributee of the
estate, or to a person upon whom such right devolves by reason of the Holder's
death, then the options shall be nontransferable by the Holder's executor or
administrator or by such person or entity.

         This Option Agreement, unless earlier terminated in the event of
Holder's death as provided above, shall terminate in all respects, and all
rights to purchase shares hereunder shall terminate, five (5) years after the
Effective Date set forth above.

         SECTION 7. RESTRICTIONS ON STOCK IN THE COMPANY. Once the Holder has
exercised the Option(s) granted hereunder, and has been issued a stock
certificate for such shares, the following restrictions shall apply:


                  (a) RESTRICTIVE LEGENDS. The certificates evidencing the
shares purchased will bear the following legends:

         THE SHARES OF STOCK REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
         RIGHTS OF FIRST OFFER AND FIRST REFUSAL IN FAVOR OF SALIX TECHNOLOGIES,
         INC., AS SET FORTH IN AN OPTION AGREEMENT BETWEEN SALIX TECHNOLOGIES,
         INC. AND THE HOLDER OF THE SHARES.

         SECURITIES REPRESENTED BY THIS CERTIFICATE (THE "SECURITIES") HAVE BEEN
         (I) ACQUIRED FOR INVESTMENT; AND (II) ISSUED AND SOLD IN RELIANCE UPON
         EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933 (THE "1933
         ACT"). THE SECURITIES CANNOT BE OFFERED FOR SALE, SOLD OR TRANSFERRED
         OTHER THAN PURSUANT TO (I) AN EFFECTIVE REGISTRATION UNDER THE 1933 ACT
         OR IN A TRANSACTION WHICH IS OTHERWISE IN COMPLIANCE WITH THE 1933 ACT;
         AND (II) EVIDENCE SATISFACTORY TO THE ISSUER OF COMPLIANCE WITH THE
         APPLICABLE SECURITIES LAWS OF ANY OTHER JURISDICTION. THE ISSUER SHALL
         BE ENTITLED TO RELY UPON AN OPINION OF COUNSEL TO THE ISSUER WITH
         RESPECT TO COMPLIANCE WITH THE ABOVE LAWS.

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                  (b) RIGHTS OF FIRST OFFER AND FIRST REFUSAL. The Holder may
not sell, exchange, or otherwise transfer the Common Stock acquired through the
exercise of such Option without first offering the Common Stock to the Company.
The Company shall have sixty (60) days, after receipt of written notification
from the Holder of his intention to transfer all, but not less than all, of the
Common Stock, to elect to purchase the Common Stock from the Holder for the
price and on the terms set forth in the Holder's notice. In the event that the
offer is not accepted by the Company, the Holder shall thereafter have the right
to negotiate a sale of all, but not less than all, of the Common Stock to any
other person; provided, however, that the Holder shall not have the right to
complete such sale without first presenting the Company with a bona fide written
offer for such Common Stock from a third party, upon which the Company shall
have the right, for a period of sixty (60) days thereafter, to purchase such
Common Stock for the price and upon equivalent terms as set forth in the bona
fide written offer. For purposes of this Section 7(b), an offer from a third
party to purchase all of the Holder's Common Stock shall not be deemed to be a
"bona fide written offer" until a deposit equal to ten percent (10%) of the
purchase price stated in such offer is placed in escrow with the Holder's
counsel of choice. If the Company does not elect to exercise its right of first
refusal within such 60-day period, then the Holder shall be free to complete the
proposed transfer or sale on the terms and conditions set forth in the bona fide
written offer within ninety (90) days thereafter. If such transfer or sale is
not completed within 90 days, the Holder shall again be required to give notice
of a bona fide written offer pursuant to this Section 7(b), which notice will
again give rise to the rights of first refusal provided above (for an additional
60 days), prior to completing such transfer. As a condition to the effectiveness
of any such transfer, the transferee shall agree to take such Common Stock
subject to all of the terms and conditions of this Section 7, and shall execute
and deliver to the Company an instrument acknowledging such acceptance, in form
and substance acceptable to the Company.

                  (c) STOCK MAY BE PLEDGED WITH COMPANY'S CONSENT.
Notwithstanding the foregoing, upon the Company's prior written consent, the
Common Stock acquired through the exercise of such Option may be pledged by the
Holder as security for a loan.

                  (d) STOCK NOT REGISTERED. The shares of Common Stock acquired
upon exercise of Options granted hereunder may not be registered under
applicable securities laws, and may not be transferred unless registered under
the applicable securities laws or unless an exemption from the registration
requirements is available.

         SECTION 8. LISTING AND REGISTRATION OF SHARES. Each Option shall be
subject to the requirement that if at any time the Board of Directors shall
determine, in its discretion, that the listing, registration, or qualification
of the shares covered thereby upon any securities exchange or under any state or
federal law or the consent or approval of any governmental regulatory body, is
necessary, or desirable as a condition of, or in connection with, the granting
of such Option or the issue or purpose of shares thereunder, such Option may not
be exercised in whole or in part unless and until such listing, registration,
qualification, consent, or approval shall have been effected or obtained free of
any conditions not acceptable to the Board of Directors of the Company.

         SECTION 9. NOTICE. Any notice to be given to the Company hereunder
shall be deemed sufficient if addressed to the Company and delivered to the
principal office of the Company, attention of the president, or such other
address as the Company may hereafter designate.

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         Any notice to be given to the Holder hereunder shall be deemed
sufficient if delivered in person to the Holder or when deposited in the mail,
postage prepaid, addressed to the Holder at the address furnished to the
Company.

         SECTION 10. GOVERNING LAW. THIS OPTION AGREEMENT SHALL BE GOVERNED BY
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE.

         SECTION 11. EFFECTIVE DATE. This Option Agreement shall be effective on
the Effective Date set forth on page 1 hereof.

         SECTION 12. BINDING UPON ESTATE AND HEIRS. This Option Agreement and
all restrictions contained herein shall be binding upon the Holder's estate,
personal representatives and heirs.




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         IN WITNESS WHEREOF, the parties have executed this Option Agreement, or
caused this option agreement to be executed, as of the Effective Date.


                                                   SALIX TECHNOLOGIES, INC.



                                                   By:
                                                      --------------------------
                                                   Name:  Daniel S. Simpkins
                                                   Title:  President


                                                   HOLDER:

                                                   -----------------------------
                                                   EUGENE CARLOCK



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                          OPTION AGREEMENT AMENDMENT 1

The Stock Option Agreement by and between SALIX Technologies, Inc. and Allen
Eugene Carlock for 7,500 shares at one dollar per share is hereby amended as
follows:

Effective Date

The effective date of the Stock Option Agreement is December 1, 1997.

The effective date of this amendment shall be December 1, 1997.

SALIX TECHNOLOGIES, INC.                 CONTRACTORS:
By:

/s/ Daniel S. Simpkins                   /s/ A. Eugene Carlock
------------------------------------     ---------------------------------------
Daniel S. Simpkins                        A. Eugene Carlock


            2/17/98                                    2/17/98
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Date                                     Date