Document:

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                       JOINT VENTURE AGREEMENT AMENDMENT

        This Joint Venture Agreement Amendment dated as of January 31, 2000, by
and among ML JWH STRATEGIC ALLOCATION FUND L.P. (the "Partnership") and JOHN W.
HENRY & COMPANY INC. ("JWH").

                                  WITNESSETH

        WHEREAS, the parties hereto entered an Joint Venture Agreement dated as
of April 25, 1996 pursuant to which JWH is acting as a commodity trading advisor
for the Partnership (as amended to the date hereof, the "Joint Venture
Agreement," certain defined terms are used herein as defined therein); and

        WHEREAS, the parties hereto wish to amend the Joint Venture Agreement in
order to provide for the termination of the exclusivity provisions contained
therein.

        NOW THEREFORE, in consideration of the premises and mutual covenants
contained in the Joint Venture Agreement and herein, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree to amend the Joint
Venture Agreement as follows:

        1. Exclusivity. The exclusivity arrangement contained in Section 31 of
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the Joint Venture Agreement shall terminate on February 29, 2000.

        2. Entire Agreement. This Amendment, together with the Joint Venture
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Agreement and all amendments thereto, constitutes the entire agreement among the
parties hereto with respect to the matters referred to herein, and no other
agreement, verbal or otherwise, shall be binding as between the parties unless
it shall be in writing and signed by the party against whom enforcement is
sought.

        3. Counterparts. This Amendment may be executed in one or more
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counterparts, each of which shall, however, together constitute one and the same
document.

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        IN WITNESS WHEREOF, the undersigned have hereto duly set forth their
hand as of the 31st day of January, 2000.

                                             ML JWH STRATEGIC ALLOCATION FUND
                                             L.P.

                                             By: MERRILL LYNCH INVESTMENT
                                                 PARTNERS INC., its general
                                                 partner

                                                 /s/ Steven B. Olgin
                                             By: ___________________________
                                                 Name: Steven B. Olgin
                                                 Title: VP and Secretary

                                                JOHN W. HENRY & COMPANY INC.

                                                 /s/ David M. Kozak
                                             By: ___________________________
                                                 Name: David M. Kozak
                                                 Title: Sr. VP

Confirmed:
not as a Joint Venturer but
solely for the limited purposes
set forth herein

MERRILL LYNCH FUTURES INC.

    /s/ John R. Frawley, Jr.
By: ________________________________
    Name:  John R. Frawley, Jr.
    Title: Chairman, Chief Executive
            Officer, President and Director<PAGE>

                                                                    Exhibit 10.8

December 22, 1999

Mr. Michael A. Gibbon
1340 Monk's Passage
Oakville, Ontario
L6M 1J5

Dear Michael:

This letter will confirm the agreement we have recently reached in connection
with your ongoing employment with Imax Corporation ("Imax") from August 1, 1999
up to and including April 30, 2001.  This letter will constitute an amendment of
your employment agreement (the "Agreement") dated January 16, 1991 and confirm
all provisions of the Agreement, except as may be amended by this letter.

1.  Term of Employment

In consideration of the agreements herein, you agree that your employment with
Imax will terminate on April 30, 2001, or such earlier date as Imax may
determine (the "Employment Term").

2. Compensation

(a)  Base Salary

You will be paid an annual base salary US$225,000 ("Base Salary") up to and
including the date of which your employment terminates.  Your Base Salary shall
be converted to Canadian dollars at an exchange rate to be fixed on the last
trading day of December of each calendar year of your employment.  The exchange
rate for 1999 will be US$1.00 equals CDN$1.53.
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(b)  Bonus

You shall continue to participate in the Imax Management Bonus Plan (as such
Plan may be amended from time to time) and your target annual bonus shall be 25%
of your Base Salary.

(c)  Stock Options

Stock options which have been granted to you under the Imax Corporation Stock
Option Plan (the "Plan") shall continue to vest, subject to applicable law, in
accordance with the terms of the various stock option agreements entered into
between you and Imax.  In consideration of the agreements herein, Imax shall
permit the options to continue to vest beyond the termination of your
employment.  Such options shall be exercisable up to and including the date
which is ten (10) years from the date of each grant, as defined in the Plan.

(d)  Termination Without Cause

In the event that Imax terminates your employment without cause before April 30,
2001, Imax shall continue to pay the Base Salary, your automobile allowance and
your 25% target bonus (on a pro rated basis) and shall continue to provide
employment benefits (to the extent paid for by the Company as at the date of
termination) and subject to the consent of the applicable insurers, up to
including April 30, 2001 (the "Severance Period").  You agree that Imax may
deduct from any payment of Base Salary, the benefit plan contributions which are
to be made by you during this period.  In addition you agree that you will have
no further right to receive any other compensation or benefits after such
termination of your employment except as are necessary under the terms of
applicable benefit plans or programs of Imax or as required by applicable law.
All payments made to you hereunder shall be deemed to include all termination
severance pay to which you are entitled pursuant to applicable statute and
common law.  The date of termination under this paragraph 2(d) shall be the date
specified in the written notice from Imax.

(e)  Retirement Benefits

During the Employment Term, you shall be entitled to receive all of your current
health and welfare benefits, including health, dental, short term disability,
long term disability and life insurance benefits.

Should you become disabled during the Employment Term, you shall continue to
receive the Stock Option benefits outlined in Section (c) above.

Effective April 30, 2001, you shall be entitled to receive retirement benefits
offered by Imax's benefit provider as outlined to you, notwithstanding the
minimum age requirement.
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3. Non-Solicitation, Confidentiality and Non-Competition

You agree to be bound by the terms of the Non-Solicitation, Confidentiality,
Non-Competition provisions attached as Schedule "A" to this letter.

If you are in agreement with all of the foregoing, kindly execute the enclosed
copy of this letter and return to the undersigned at your earliest convenience.

Yours very truly,

IMAX CORPORATION

Per:     /s/ Robert D. Lister
         --------------------
Name:  Robert D. Lister
Title: Senior Vice President,
       Legal Affairs & General Counsel

Per:     /s/ G. Mary Ruby
         ----------------
Name:  G. Mary Ruby
Title: Vice President, Legal Affairs

                               AGREED AND ACCEPTED
                               As of the 22 day of December, 1999.
                                         --

                               /s/ Michael A. Gibbon
                               ---------------------
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                                   Schedule A

               NON-SOLICITATION, CONFIDENTIALITY, NON-COMPETITION
               --------------------------------------------------

1.   Non-solicitation.  For so long as Michael A. Gibbon (the "Executive") is
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     employed by Imax or receiving payment therefrom and continuing for two
     years thereafter, notwithstanding whether the Executive's employment is
     terminated with or without Cause or whether the Executive resigns, the
     Executive shall not, without the prior written consent of Imax, directly or
     indirectly, for the Executive's own benefit or the benefit of any other
     person, whether as a sole proprietor, member of a partnership, stockholder
     or investor (other than a stockholder or investor owning not more than a 5%
     interest), officer or director of a corporation, or as a trustee,
     executive, associate, consultant, principal or agent of any person,
     partnership, corporation or other business organization or entity other
     than Imax: (x) solicit or endeavour to entice away from Imax, any person or
     entity who is, or, during the then most recent 12-month period, was
     employed by, or had served as an agent or consultant of Imax; or (y)
     solicit, endeavour to entice away or gain the custom of, canvass or
     interfere with Imax's relationship with any person or entity who is, or was
     within the then most recent 12-month period, a supplier, customer or client
     (or reasonably anticipated to become a supplier, customer or client) of
     Imax and with whom the Executive had dealings during his employment with
     Imax. The Executive confirms that all restrictions in this Paragraph are
     reasonable and valid and waives all defences to the strict enforcement
     thereof.

2.   Non-Competition  For so long as the Executive is employed by Imax or
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     receiving payment hereunder and continuing for a period of two years after
     the date of the termination of the employment of the Executive with Imax,
     notwithstanding whether the Executive's employment is terminated with or
     without Cause or whether the Executive resigns, the Executive shall not,
     without the prior written consent of Imax, directly or indirectly anywhere
     within Canada, the United States, Europe or Asia, as a sole proprietor,
     member of a partnership, stockholder or investor (other than a stockholder
     or investor owning not more than a 5% interest), officer or director of a
     corporation, or as a trustee, Executive, associate, consultant, principal
     or agent of any person, partnership, corporation or other business
     organization or entity other than Imax, render any service to or in any way
     be affiliated with a competitor (or any person or entity that is, at the
     time the Executive would otherwise commence rendering services to or
     become, affiliated with such person or entity, reasonably anticipated to
     become a competitor) of
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     Imax (a "Competitor"), which is engaged or reasonably anticipated to become
     engaged in designing or supplying large format theatres, designing or
     distributing projection or sound systems for large format theatres,
     designing or supplying digital or other electronic film, projection systems
     (regardless of image delivery system used) or sound technology, designing
     or supplying motion simulation attractions or producing or distributing
     films specifically for theatres or motion simulation attractions which use
     the technology or competitive technology to that referred to above.  The
     Executive confirms that all restrictions in this Paragraph are reasonable
     and valid and waives all defenses to the strict enforcement thereof.

3.   Confidentiality. The Executive covenants and agrees with Imax that he will
     ----------------
     not at any time during employment hereunder or thereafter up to and
     including the date on which options granted to him by Imax under the Imax
     Corporation Stock Option Plan terminate, except in performance of his
     obligations to Imax hereunder or with the prior written consent of the
     senior operation officer of Imax, directly or indirectly, disclose or use
     any secret or confidential information that he may learn or has learned by
     reason of his association with Imax. The term "confidential information'
     includes information not previously disclosed to the public or to the trade
     by Imax's management, or otherwise in the public domain, with respect to
     Imax's products, facilities, applications and methods, trade secrets and
     other intellectual property, systems, procedures, manuals, confidential
     reports, product price lists, customer lists, technical information,
     financial information, business plans, prospects or opportunities, but
     shall exclude any information which (i) is or becomes available to the
     public or is generally known in the industry or industries in which Imax
     operates other than as a result of disclosure by the Executive in violation
     of his agreements under this Paragraph 3 or (ii) the Executive is required
     to disclose under any applicable laws, regulations or directives of any
     government agency, tribunal or authority having jurisdiction in the matter
     or under subpoena or other process of law. The Executive confirms that all
     restrictions in this Paragraph 3 are reasonable and valid and waives all
     defences to the strict enforcement thereof.

4.   Exclusive Property.  The Executive confirms that all confidential
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     information is and shall remain the exclusive property of Imax. All
     business records, papers and documents regardless of the form of their
     records kept or made by Executive relating to the business of Imax shall be
     and remain the property of Imax, and shall be promptly returned by the
     Executive to Imax upon any termination of employment.

5.   Injunctive Relief.  Without intending to limit the remedies available to
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     Imax, the Executive acknowledges that a material breach of any of the
     covenants contained herein will result in material and irreparable injury
     to Imax for which there is no adequate remedy at law, that it will not be
     possible to measure damages for such injuries precisely and that, in the
     event of such a breach or threat thereof, Imax
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     shall be entitled to seek a temporary restraining order and/or a
     preliminary, interim or permanent injunction restraining the Executive from
     engaging in activities prohibited herein or such other relief as may be
     required specifically to enforce any of the covenants herein.  The
     Executive waives any defences to the strict enforcement by Imax of the
     covenants contained herein.  If for any reason it is held that the
     restrictions hereunder are not reasonable or that consideration therefor is
     inadequate, such restrictions shall be interpreted or modified to include
     as much of the duration and scope identified herein as will render such
     restrictions valid and enforceable.

6.   Representation.  The Executive represents and warrants that he is not
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     subject to any non-competition covenant or any other agreement with any
     party which would in any manner restrict or limit his ability to render the
     services required of him hereunder.

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