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                                                                   EXHIBIT 10.39


                          REGISTRATION RIGHTS AGREEMENT

      REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of _____ __,
2002, by and between PROBEX CORP., a Delaware corporation, (the "COMPANY"), and
FUSION CAPITAL FUND II, LLC (together with it permitted assigns, the "BUYER").
Capitalized terms used herein and not otherwise defined herein shall have the
respective meanings set forth in the Common Stock Purchase Agreement by and
between the parties hereto dated as of _______, 2002 (as amended, restated,
supplemented or otherwise modified from time to time, the "PURCHASE AGREEMENT").

                                    WHEREAS:

      A.    The Company has agreed, upon the terms and subject to the conditions
of the Purchase Agreement, to issue to the Buyer (i) up to Twenty Million
Dollars ($20,000,000) of the Company's common stock, par value $0.001 per share
(the "COMMON STOCK") (the "PURCHASE SHARES"), and (ii) such number of shares of
Common Stock as is required pursuant to Section 4(f) of the Purchase Agreement
(the "COMMITMENT SHARES"); and

      B.    To induce the Buyer to enter into the Purchase Agreement, the
Company has agreed to provide certain registration rights under the Securities
Act of 1933, as amended, and the rules and regulations thereunder, or any
similar successor statute (collectively, the "1933 ACT"), and applicable state
securities laws.

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and the Buyer hereby
agree as follows:

      1.    DEFINITIONS.

            As used in this Agreement, the following terms shall have the
following meanings:

            a.    "INVESTOR" means the Buyer, any transferee or assignee thereof
to whom a Buyer assigns its rights under this Agreement and who agrees to become
bound by the provisions of this Agreement in accordance with Section 9 and any
transferee or assignee thereof to whom a transferee or assignee assigns its
rights under this Agreement and who agrees to become bound by the provisions of
this Agreement in accordance with Section 9.

            b.    "PERSON" means any person or entity including any corporation,
a limited liability company, an association, a partnership, an organization, a
business, an individual, a governmental or political subdivision thereof or a
governmental agency.

            c.    "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing one or more registration
statements of the Company in compliance with the 1933 Act and pursuant to Rule
415 under the 1933 Act or any successor rule providing for offering securities
on a continuous basis ("RULE 415"), and the declaration or ordering of
effectiveness of such registration statement(s) by the United States Securities
and Exchange Commission (the "SEC").
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            d.    "REGISTRABLE SECURITIES" means the Purchase Shares which have
been, or which may from time to time be, issued or issuable upon purchases of
the Available Amount under the Purchase Agreement (without regard to any
limitation or restriction on purchases) and the Commitment Shares issued or
issuable to the Investor and any shares of capital stock issued or issuable with
respect to the Purchase Shares, the Commitment Shares or the Purchase Agreement
as a result of any stock split, stock dividend, recapitalization, exchange or
similar event or otherwise, without regard to any limitation on purchases under
the Purchase Agreement.

            e.    "REGISTRATION STATEMENT" means the registration statement of
the Company which the Company has agreed to file pursuant to Section 4(a) of the
Purchase Agreement with respect to the sale of the Registrable Securities.

      2.    REGISTRATION.

            a.    Mandatory Registration. The Company shall use reasonable best
efforts to keep the Registration Statement effective pursuant to Rule 415
promulgated under the 1933 Act and available for sales of all of the Registrable
Securities at all times until the earlier of (i) the date as of which the
Investor may sell all of the Registrable Securities without restriction pursuant
to Rule 144(k) promulgated under the 1933 Act (or successor thereto) or (ii) the
date on which (A) the Investor shall have sold all the Registrable Securities
and no available amount remains under the Purchase Agreement (the "REGISTRATION
PERIOD"). The Registration Statement (including any amendments or supplements
thereto and prospectuses contained therein) shall not contain any untrue
statement of a material fact or omit to state a material fact required to be
stated therein, or necessary to make the statements therein, in light of the
circumstances in which they were made, not misleading.

            b.    Rule 424 Prospectus. The Company shall, as required by
applicable securities regulations, from time to time file with the SEC, pursuant
to Rule 424 promulgated under the 1933 Act, the prospectus and prospectus
supplements, if any, to be used in connection with sales of the Registrable
Securities under the Registration Statement. The Investor and its counsel shall
have a reasonable opportunity to review and comment upon such prospectus prior
to its filing with the SEC. The Investor shall use its reasonable best efforts
to comment upon such prospectus within one (1) Trading Day from the date the
Investor receives the final version of such prospectus.

            c.    Sufficient Number of Shares Registered. In the event the
number of shares available under the Registration Statement is insufficient to
cover all of the Registrable Securities, the Company shall amend the
Registration Statement or file a new registration statement (a "NEW REGISTRATION
STATEMENT"), so as to cover all of such Registrable Securities as soon as
practicable, but in any event not later than ten (10) Trading Days after the
necessity therefore arises. The Company shall use it reasonable best efforts to
cause such amendment and/or New Registration Statement to become effective as
soon as practicable following the filing thereof.

3.    RELATED OBLIGATIONS.

      With respect to the Registration Statement and whenever any Registrable
Securities are to be registered pursuant to Section 2(b) including on any New
Registration Statement, the Company shall use its reasonable best efforts to
effect the registration of the Registrable Securities in accordance with the
intended method of disposition thereof and, pursuant thereto, the Company shall
have the following obligations:


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            a.    The Company shall prepare and file with the SEC such
amendments (including post-effective amendments) and supplements to any
registration statement and the prospectus used in connection with such
registration statement, which prospectus is to be filed pursuant to Rule 424
promulgated under the 1933 Act, as may be necessary to keep the Registration
Statement or any New Registration Statement effective at all times during the
Registration Period, and, during such period, comply with the provisions of the
1933 Act with respect to the disposition of all Registrable Securities of the
Company covered by the Registration Statement or any New Registration Statement
until such time as all of such Registrable Securities shall have been disposed
of in accordance with the intended methods of disposition by the seller or
sellers thereof as set forth in such registration statement.

            b.    The Company shall permit the Investor to review and comment
upon the Registration Statement or any New Registration Statement and all
amendments and supplements thereto at least two (2) Trading Days prior to their
filing with the SEC, and not file any document in a form to which Investor
reasonably objects. The Investor shall use its reasonable best efforts to
comment upon the Registration Statement or any New Registration Statement and
any amendments or supplements thereto within two (2) Trading Days from the date
the Investor receives the final version thereof. The Company shall furnish to
the Investor, without charge any correspondence from the SEC or the staff of the
SEC to the Company or its representatives relating to the Registration Statement
or any New Registration Statement.

            c.    Upon request of the Investor, the Company shall furnish to the
Investor, (i) promptly after the same is prepared and filed with the SEC, at
least one copy of such registration statement and any amendment(s) thereto,
including financial statements and schedules, all documents incorporated therein
by reference and all exhibits, (ii) upon the effectiveness of any registration
statement, ten (10) copies of the prospectus included in such registration
statement and all amendments and supplements thereto (or such other number of
copies as the Investor may reasonably request) and (iii) such other documents,
including copies of any preliminary or final prospectus, as the Investor may
reasonably request from time to time in order to facilitate the disposition of
the Registrable Securities owned by the Investor.

            d.    The Company shall use reasonable best efforts to (i) register
and qualify the Registrable Securities covered by a registration statement under
such other securities or "blue sky" laws of such jurisdictions in the United
States as the Investor reasonably requests, (ii) prepare and file in those
jurisdictions, such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; provided, however, that
the Company shall not be required in connection therewith or as a condition
thereto to (x) qualify to do business in any jurisdiction where it would not
otherwise be required to qualify but for this Section 3(d), (y) subject itself
to general taxation in any such jurisdiction, or (z) file a general consent to
service of process in any such jurisdiction. The Company shall promptly notify
the Investor who holds Registrable Securities of the receipt by the Company of
any notification with respect to the suspension of the registration or
qualification of any of the Registrable Securities for sale under the securities
or "blue sky" laws of any jurisdiction in the United States or its receipt of
actual notice of the initiation or threatening of any proceeding for such
purpose.

            e.    As promptly as practicable after becoming aware of such event
or facts, the Company shall notify the Investor in writing of the happening of
any event or existence of such facts as a


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result of which the prospectus included in any registration statement, as then
in effect, includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading, and promptly prepare a supplement or amendment to such registration
statement to correct such untrue statement or omission, and deliver ten (10)
copies of such supplement or amendment to the Investor (or such other number of
copies as the Investor may reasonably request). The Company shall also promptly
notify the Investor in writing (i) when a prospectus or any prospectus
supplement or post-effective amendment has been filed, and when a registration
statement or any post-effective amendment has become effective (notification of
such effectiveness shall be delivered to the Investor by facsimile on the same
day of such effectiveness and by overnight mail), (ii) of any request by the SEC
for amendments or supplements to any registration statement or related
prospectus or related information, and (iii) of the Company's reasonable
determination that a post-effective amendment to a registration statement would
be appropriate.

            f.    The Company shall use its reasonable best efforts to prevent
the issuance of any stop order or other suspension of effectiveness of any
registration statement, or the suspension of the qualification of any
Registrable Securities for sale in any jurisdiction and, if such an order or
suspension is issued, to obtain the withdrawal of such order or suspension at
the earliest possible moment and to notify the Investor of the issuance of such
order and the resolution thereof or its receipt of actual notice of the
initiation or threat of any proceeding for such purpose.

            g.    The Company shall (i) cause all the Registrable Securities to
be listed on each securities exchange on which securities of the same class or
series issued by the Company are then listed, if any, if the listing of such
Registrable Securities is then permitted under the rules of such exchange, or
(ii) secure designation and quotation of all the Registrable Securities on the
[_____________]. The Company shall pay all fees and expenses in connection with
satisfying its obligation under this Section.

            h.    The Company shall cooperate with the Investor to facilitate
the timely preparation and delivery of certificates (not bearing any restrictive
legend) representing the Registrable Securities to be offered pursuant to any
registration statement and enable such certificates to be in such denominations
or amounts as the Investor may reasonably request and registered in such names
as the Investor may request.

            i.    The Company shall at all times provide a transfer agent and
registrar with respect to its Common Stock.

            j.    If reasonably requested by the Investor, the Company shall (i)
immediately incorporate in a prospectus supplement or post-effective amendment
such information as the Investor believes should be included therein relating to
the sale and distribution of Registrable Securities, including, without
limitation, information with respect to the number of Registrable Securities
being sold, the purchase price being paid therefore and any other terms of the
offering of the Registrable Securities; (ii) make all required filings of such
prospectus supplement or post-effective amendment as soon as notified of the
matters to be incorporated in such prospectus supplement or post-effective
amendment; and (iii) supplement or make amendments to any registration
statement.

            k.    The Company shall use its reasonable best efforts to cause the
Registrable Securities covered by the any registration statement to be
registered with or approved by such other governmental agencies or authorities
as may be necessary to consummate the disposition of such Registrable
Securities.


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            l.    Within one (1) Trading Day after any registration statement
which includes the Registrable Securities is ordered effective by the SEC, the
Company shall deliver, and shall cause legal counsel for the Company to deliver,
to the transfer agent for such Registrable Securities (with copies to the
Investor) confirmation that such registration statement has been declared
effective by the SEC in the form attached hereto as Exhibit A.

            m.    The Company shall take all other reasonable actions necessary
to expedite and facilitate disposition by the Investor of Registrable Securities
pursuant to any registration statement.

      4.    OBLIGATIONS OF THE INVESTOR.

            a.    The Company shall notify the Investor in writing of the
information the Company reasonably requires from the Investor in connection with
any registration statement hereunder. The Investor shall furnish to the Company
such information regarding itself, the Registrable Securities held by it and the
intended method of disposition of the Registrable Securities held by it as shall
be reasonably required to effect the registration of such Registrable Securities
and shall execute such documents in connection with such registration as the
Company may reasonably request.

            b.    The Investor agrees to cooperate with the Company as
reasonably requested by the Company in connection with the preparation and
filing of any registration statement hereunder.

            c.    The Investor agrees that, upon receipt of any notice from the
Company of the happening of any event or existence of facts of the kind
described in Section 3(f) or the first sentence of 3(e), the Investor will
immediately discontinue disposition of Registrable Securities pursuant to any
registration statement(s) covering such Registrable Securities until the
Investor's receipt of the copies of the supplemented or amended prospectus
contemplated by Section 3(f) or the first sentence of 3(e). Notwithstanding
anything to the contrary, the Company shall cause its transfer agent to promptly
deliver shares of Common Stock without any restrictive legend in accordance with
the terms of the Purchase Agreement in connection with any sale of Registrable
Securities with respect to which an Investor has entered into a contract for
sale prior to the Investor's receipt of a notice from the Company of the
happening of any event of the kind described in Section 3(f) or the first
sentence of 3(e) and for which the Investor has not yet settled.

      5.    EXPENSES OF REGISTRATION.

            All reasonable expenses, other than sales or brokerage commissions,
incurred in connection with registrations, filings or qualifications pursuant to
Sections 2 and 3, including, without limitation, all registration, listing and
qualifications fees, printers and accounting fees, and fees and disbursements of
counsel for the Company, shall be paid by the Company.

      6.    INDEMNIFICATION.

            a.    To the fullest extent permitted by law, the Company will, and
hereby does, indemnify, hold harmless and defend the Investor, each Person, if
any, who controls the Investor, the members, the directors, officers, partners,
employees, agents, representatives of the Investor and each Person, if any, who
controls the Investor within the meaning of the 1933 Act or the Securities
Exchange Act of 1934, as amended (the "1934 ACT") (each, an "INDEMNIFIED
PERSON"), against any losses, claims, damages, liabilities, judgments, fines,
penalties, charges, costs, attorneys' fees, amounts paid in settlement or
expenses, joint or several, (collectively, "CLAIMS") incurred in investigating,
preparing or defending any


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action, claim, suit, inquiry, proceeding, investigation or appeal taken from the
foregoing by or before any court or governmental, administrative or other
regulatory agency, body or the SEC, whether pending or threatened, whether or
not an indemnified party is or may be a party thereto ("INDEMNIFIED DAMAGES"),
to which any of them may become subject insofar as such Claims (or actions or
proceedings, whether commenced or threatened, in respect thereof) arise out of
or are based upon: (i) any untrue statement or alleged untrue statement of a
material fact in the Registration Statement, any New Registration Statement or
any post-effective amendment thereto or in any filing made in connection with
the qualification of the offering under the securities or other "blue sky" laws
of any jurisdiction in which Registrable Securities are offered ("BLUE SKY
FILING"), or the omission or alleged omission to state a material fact required
to be stated therein or necessary to make the statements therein not misleading,
(ii) any untrue statement or alleged untrue statement of a material fact
contained in the final prospectus (as amended or supplemented, if the Company
files any amendment thereof or supplement thereto with the SEC) or the omission
or alleged omission to state therein any material fact necessary to make the
statements made therein, in light of the circumstances under which the
statements therein were made, not misleading, (iii) any violation or alleged
violation by the Company of the 1933 Act, the 1934 Act, any other law,
including, without limitation, any state securities law, or any rule or
regulation thereunder relating to the offer or sale of the Registrable
Securities pursuant to the Registration Statement or any New Registration
Statement or (iv) any material violation by the Company of this Agreement (the
matters in the foregoing clauses (i) through (iv) being, collectively,
"VIOLATIONS"). The Company shall reimburse each Indemnified Person promptly as
such expenses are incurred and are due and payable, for any legal fees or other
reasonable expenses incurred by them in connection with investigating or
defending any such Claim. Notwithstanding anything to the contrary contained
herein, the indemnification agreement contained in this Section 6(a): (i) shall
not apply to a Claim by an Indemnified Person arising out of or based upon a
Violation which occurs in reliance upon and in conformity with information
furnished in writing to the Company by such Indemnified Person expressly for use
in connection with the preparation of the Registration Statement, any New
Registration Statement or any such amendment thereof or supplement thereto, if
such prospectus was timely made available by the Company pursuant to Section
3(c) or Section 3(e); (ii) with respect to any superceded prospectus, shall not
inure to the benefit of any such person from whom the person asserting any such
Claim purchased the Registrable Securities that are the subject thereof (or to
the benefit of any person controlling such person) if the untrue statement or
omission of material fact contained in the superceded prospectus was corrected
in the revised prospectus, as then amended or supplemented, if such revised
prospectus was timely made available by the Company pursuant to Section 3(c) or
Section 3(e), and the Indemnified Person was promptly advised in writing not to
use the incorrect prospectus prior to the use giving rise to a violation and
such Indemnified Person, notwithstanding such advice, used it; (iii) shall not
be available to the extent such Claim is based on a failure of the Investor to
deliver or to cause to be delivered the prospectus made available by the
Company, if such prospectus was timely made available by the Company pursuant to
Section 3(c) or Section 3(e); and (iv) shall not apply to amounts paid in
settlement of any Claim if such settlement is effected without the prior written
consent of the Company, which consent shall not be unreasonably withheld. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of the Indemnified Person and shall survive the transfer of
the Registrable Securities by the Investor pursuant to Section 9.

            b.    In connection with the Registration Statement or any New
Registration Statement, the Investor agrees to severally and not jointly
indemnify, hold harmless and defend, to the same extent and in the same manner
as is set forth in Section 6(a), the Company, each of its directors, each of its
officers who signs the Registration Statement or any New Registration Statement,
each Person, if any, who controls the Company within the meaning of the 1933 Act
or the 1934 Act (collectively and together with an Indemnified Person, an
"INDEMNIFIED PARTY"), against any Claim or Indemnified Damages to which any of
them may become subject, under the 1933 Act, the 1934 Act or otherwise, insofar
as such Claim or


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Indemnified Damages arise out of or are based upon any Violation, in each case
to the extent, and only to the extent, that such Violation occurs in reliance
upon and in conformity with written information about the Investor set forth on
Exhibit B attached hereto and furnished to the Company by the Investor expressly
for use in connection with such registration statement; and, subject to Section
6(d), the Investor will reimburse any legal or other expenses reasonably
incurred by them in connection with investigating or defending any such Claim;
provided, however, that the indemnity agreement contained in this Section 6(b)
and the agreement with respect to contribution contained in Section 7 shall not
apply to amounts paid in settlement of any Claim if such settlement is effected
without the prior written consent of the Investor, which consent shall not be
unreasonably withheld; provided, further, however, that the Investor shall be
liable under this Section 6(b) for only that amount of a Claim or Indemnified
Damages as does not exceed the net proceeds to the Investor as a result of the
sale of Registrable Securities pursuant to such registration statement. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of such Indemnified Party and shall survive the transfer of
the Registrable Securities by the Investor pursuant to Section 9.

            c.    Promptly after receipt by an Indemnified Person or Indemnified
Party under this Section 6 of notice of the commencement of any action or
proceeding (including any governmental action or proceeding) involving a Claim,
such Indemnified Person or Indemnified Party shall, if a Claim in respect
thereof is to be made against any indemnifying party under this Section 6,
deliver to the indemnifying party a written notice of the commencement thereof,
and the indemnifying party shall have the right to participate in, and, to the
extent the indemnifying party so desires, jointly with any other indemnifying
party similarly noticed, to assume control of the defense thereof with counsel
mutually satisfactory to the indemnifying party and the Indemnified Person or
the Indemnified Party, as the case may be; provided, however, that an
Indemnified Person or Indemnified Party shall have the right to retain its own
counsel with the fees and expenses to be paid by the indemnifying party, if, in
the reasonable opinion of counsel retained by the indemnifying party, the
representation by such counsel of the Indemnified Person or Indemnified Party
and the indemnifying party would be inappropriate due to actual or potential
differing interests between such Indemnified Person or Indemnified Party and any
other party represented by such counsel in such proceeding. The Indemnified
Party or Indemnified Person shall cooperate fully with the indemnifying party in
connection with any negotiation or defense of any such action or claim by the
indemnifying party and shall furnish to the indemnifying party all information
reasonably available to the Indemnified Party or Indemnified Person which
relates to such action or claim. The indemnifying party shall keep the
Indemnified Party or Indemnified Person fully apprised at all times as to the
status of the defense or any settlement negotiations with respect thereto. No
indemnifying party shall be liable for any settlement of any action, claim or
proceeding effected without its written consent, provided, however, that the
indemnifying party shall not unreasonably withhold, delay or condition its
consent. No indemnifying party shall, without the consent of the Indemnified
Party or Indemnified Person, consent to entry of any judgment or enter into any
settlement or other compromise which does not include as an unconditional term
thereof the giving by the claimant or plaintiff to such Indemnified Party or
Indemnified Person of a release from all liability in respect to such claim or
litigation. Following indemnification as provided for hereunder, the
indemnifying party shall be subrogated to all rights of the Indemnified Party or
Indemnified Person with respect to all third parties, firms or corporations
relating to the matter for which indemnification has been made. The failure to
deliver written notice to the indemnifying party within a reasonable time of the
commencement of any such action shall not relieve such indemnifying party of any
liability to the Indemnified Person or Indemnified Party under this Section 6,
except to the extent that the indemnifying party is prejudiced in its ability to
defend such action.


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            d.    The indemnification required by this Section 6 shall be made
by periodic payments of the amount thereof during the course of the
investigation or defense, as and when bills are received or Indemnified Damages
are incurred.

            e.    The indemnity agreements contained herein shall be in addition
to (i) any cause of action or similar right of the Indemnified Party or
Indemnified Person against the indemnifying party or others, and (ii) any
liabilities the indemnifying party may be subject to pursuant to the law.

      7.    CONTRIBUTION.

            To the extent any indemnification by an indemnifying party is
prohibited or limited by law, the indemnifying party agrees to make the maximum
contribution with respect to any amounts for which it would otherwise be liable
under Section 6 to the fullest extent permitted by law; provided, however, that:
(i) no seller of Registrable Securities guilty of fraudulent misrepresentation
(within the meaning of Section 11(f) of the 1933 Act) shall be entitled to
contribution from any seller of Registrable Securities who was not guilty of
fraudulent misrepresentation; and (ii) contribution by any seller of Registrable
Securities shall be limited in amount to the net amount of proceeds received by
such seller from the sale of such Registrable Securities.

      8.    REPORTS AND DISCLOSURE UNDER THE SECURITIES ACTS.

            With a view to making available to the Investor the benefits of Rule
144 promulgated under the 1933 Act or any other similar rule or regulation of
the SEC that may at any time permit the Investor to sell securities of the
Company to the public without registration ("RULE 144"), the Company agrees to:

            a.    make and keep public information available, as those terms are
understood and defined in Rule 144;

            b.    file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements and the filing of such reports
and other documents is required for the applicable provisions of Rule 144; and

            c.    furnish to the Investor so long as the Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company that it has complied with the reporting and or disclosure provisions of
Rule 144, the 1933 Act and the 1934 Act, (ii) a copy of the most recent annual
or quarterly report of the Company and such other reports and documents so filed
by the Company, and (iii) such other information as may be reasonably requested
to permit the Investor to sell such securities pursuant to Rule 144 without
registration.

      9.    ASSIGNMENT OF REGISTRATION RIGHTS.

            The Company shall not assign this Agreement or any rights or
obligations hereunder without the prior written consent of the Investor,
including by merger or consolidation. The Investor may not assign its rights
under this Agreement without the written consent of the Company, other than to
an affiliate of the Investor controlled by Steven G. Martin or Joshua B.
Scheinfeld.


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<PAGE>
      10.   AMENDMENT OF REGISTRATION RIGHTS.

            Provisions of this Agreement may be amended and the observance
thereof may be waived (either generally or in a particular instance and either
retroactively or prospectively), only with the written consent of the Company
and the Investor.

      11.   MISCELLANEOUS.

            a.    A Person is deemed to be a holder of Registrable Securities
whenever such Person owns or is deemed to own of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more Persons with respect to the same Registrable
Securities, the Company shall act upon the basis of instructions, notice or
election received from the registered owner of such Registrable Securities.

            b.    Any notices, consents, waivers or other communications
required or permitted to be given under the terms of this Agreement must be in
writing and will be deemed to have been delivered: (i) upon receipt, when
delivered personally; (ii) upon receipt, when sent by facsimile (provided
confirmation of transmission is mechanically or electronically generated and
kept on file by the sending party); or (iii) one (1) Trading Day after deposit
with a nationally recognized overnight delivery service, in each case properly
addressed to the party to receive the same. The addresses and facsimile numbers
for such communications shall be:

      If to the Company:
            Probex Corp.
            15510 Wright Brothers Drive
            Addison, TX 75001
            Telephone:  972-788-4772
            Facsimile:  972-980-7068
            Attention:  _________

      With a copy to:
            __________
            __________
            __________
            Telephone:  _________
            Facsimile:  _________
            Attention:  _________

      If to the Investor:
            Fusion Capital Fund II, LLC
            222 Merchandise Mart Plaza, Suite 9-112
            Chicago, IL 60654
            Telephone:  312-644-6644
            Facsimile:  312-644-6244
            Attention:  Steven G.  Martin

or at such other address and/or facsimile number and/or to the attention of such
other person as the recipient party has specified by written notice given to
each other party three (3) Trading Days prior to the effectiveness of such
change. Written confirmation of receipt (A) given by the recipient of such
notice,


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<PAGE>
consent, waiver or other communication, (B) mechanically or electronically
generated by the sender's facsimile machine containing the time, date, recipient
facsimile number and an image of the first page of such transmission or (C)
provided by a nationally recognized overnight delivery service, shall be
rebuttable evidence of personal service, receipt by facsimile or receipt from a
nationally recognized overnight delivery service in accordance with clause (i),
(ii) or (iii) above, respectively.

            c.    Failure of any party to exercise any right or remedy under
this Agreement or otherwise, or delay by a party in exercising such right or
remedy, shall not operate as a waiver thereof.

            d.    The corporate laws of the State of Delaware shall govern all
issues concerning the relative rights of the Company and its stockholders. All
other questions concerning the construction, validity, enforcement and
interpretation of this Agreement shall be governed by the internal laws of the
State of Illinois, without giving effect to any choice of law or conflict of law
provision or rule (whether of the State of Illinois or any other jurisdictions)
that would cause the application of the laws of any jurisdictions other than the
State of Illinois. Each party hereby irrevocably submits to the exclusive
jurisdiction of the state and federal courts sitting the City of Chicago, for
the adjudication of any dispute hereunder or in connection herewith or with any
transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any suit, action or proceeding, any claim
that it is not personally subject to the jurisdiction of any such court, that
such suit, action or proceeding is brought in an inconvenient forum or that the
venue of such suit, action or proceeding is improper. Each party hereby
irrevocably waives personal service of process and consents to process being
served in any such suit, action or proceeding by mailing a copy thereof to such
party at the address for such notices to it under this Agreement and agrees that
such service shall constitute good and sufficient service of process and notice
thereof. Nothing contained herein shall be deemed to limit in any way any right
to serve process in any manner permitted by law. If any provision of this
Agreement shall be invalid or unenforceable in any jurisdiction, such invalidity
or unenforceability shall not affect the validity or enforceability of the
remainder of this Agreement in that jurisdiction or the validity or
enforceability of any provision of this Agreement in any other jurisdiction.
EACH PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE, AND AGREES NOT TO
REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN
CONNECTION HEREWITH OR ARISING OUT OF THIS AGREEMENT OR ANY TRANSACTION
CONTEMPLATED HEREBY.

            e.    This Agreement, and the Purchase Agreement constitute the
entire agreement among the parties hereto with respect to the subject matter
hereof and thereof. There are no restrictions, promises, warranties or
undertakings, other than those set forth or referred to herein and therein. This
Agreement and the Purchase Agreement supersede all prior agreements and
understandings among the parties hereto with respect to the subject matter
hereof and thereof.

            f.    Subject to the requirements of Section 9, this Agreement shall
inure to the benefit of and be binding upon the permitted successors and assigns
of each of the parties hereto.

            g.    The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

            h.    This Agreement may be executed in identical counterparts, each
of which shall be deemed an original but all of which shall constitute one and
the same agreement. This Agreement, once executed by a party, may be delivered
to the other party hereto by facsimile transmission of a copy of this Agreement
bearing the signature of the party so delivering this Agreement.


                                       10
<PAGE>
            i.    Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

            j.    The language used in this Agreement will be deemed to be the
language chosen by the parties to express their mutual intent and no rules of
strict construction will be applied against any party.

            k.    This Agreement is intended for the benefit of the parties
hereto and their respective permitted successors and assigns, and is not for the
benefit of, nor may any provision hereof be enforced by, any other Person.



                                   * * * * * *


                                       11
<PAGE>
      IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be duly executed as of day and year first above written.



                                    THE COMPANY:

                                    PROBEX CORP.


                                    By:______________________
                                    Name:
                                    Title:


                                    BUYER:

                                    FUSION CAPITAL FUND II, LLC
                                    BY: FUSION CAPITAL PARTNERS, LLC
                                    BY: SGM HOLDINGS CORP.

                                    By:_______________________
                                    Name: Steven G. Martin
                                    Title: President





                                       12
<PAGE>
                                    EXHIBIT A

                        TO REGISTRATION RIGHTS AGREEMENT

                         FORM OF NOTICE OF EFFECTIVENESS
                            OF REGISTRATION STATEMENT

[Date]

[TRANSFER AGENT]
___________________
___________________

Re: [__________]

Ladies and Gentlemen:

       We are counsel to Probex Corp., a Delaware corporation (the "COMPANY"),
and have represented the Company in connection with that certain Common Stock
Purchase Agreement, dated as of _______, 2002 (the "PURCHASE AGREEMENT"),
entered into by and between the Company and Fusion Capital Fund II, LLC (the
"BUYER") pursuant to which the Company has agreed to issue to the Holder shares
of the Company's Common Stock, par value $0.001 per share (the "COMMON STOCK"),
in an amount up to Twenty Million Dollars ($20,000,000) (the "PURCHASE SHARES"),
in accordance with the terms of the Purchase Agreement. Pursuant to the Purchase
Agreement, the Company also has entered into a Registration Rights Agreement,
dated as of ______, 2002, with the Buyer (the "REGISTRATION RIGHTS AGREEMENT")
pursuant to which the Company agreed, among other things, to register the
Purchase Shares and the Commitment Shares under the Securities Act of 1933, as
amended (the "1933 Act"). In connection with the Company's obligations under the
Purchase Agreement and the Registration Rights Agreement, on _______, 2002, the
Company filed a Registration Statement (File No. 333-_________) (the
"REGISTRATION STATEMENT") with the Securities and Exchange Commission (the
"SEC") relating to the sale of the Purchase Shares and the Commitment Shares.

       In connection with the foregoing, we advise you that a member of the
SEC's staff has advised us by telephone that the SEC has entered an order
declaring the Registration Statement effective under the 1933 Act at 5:00 P.M.
on __________, 2002 and we have no knowledge, after telephonic inquiry of a
member of the SEC's staff, that any stop order suspending its effectiveness has
been issued or that any proceedings for that purpose are pending before, or
threatened by, the SEC and the Purchase Shares, and the Commitment Shares are
available for sale under the 1933 Act pursuant to the Registration Statement.

       The Buyer has confirmed it shall comply with all securities laws and
regulations applicable to it including applicable prospectus delivery
requirements upon sale of the Purchase Shares and the Commitment Shares.


                                    Very truly yours,
                                    [Company Counsel]
                                    By:____________________

CC:    Fusion Capital Fund II, LLC
<PAGE>
                                    EXHIBIT B

                        TO REGISTRATION RIGHTS AGREEMENT

     INFORMATION ABOUT THE INVESTOR FURNISHED TO THE COMPANY BY THE INVESTOR
         EXPRESSLY FOR USE IN CONNECTION WITH THE REGISTRATION STATEMENT