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                                                                    EXHIBIT 8.01

                  [LETTERHEAD OF MAYER, BROWN, ROWE & MAW LLP]

October 6, 2004

CIS Investments, Inc.
Managing Owner of
JWH Global Trust
233 South Wacker Drive
Suite 2300
Chicago, IL 60606

Ladies and Gentlemen:

         We have acted as your counsel in connection with the preparation and
filing of the Registration Statement on Form S-1 (the "Registration Statement")
with the Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Act") on or about October 6, 2004.

         In connection with the filing of the Registration Statement, you have
requested our opinions concerning (i) the qualification and taxation for Federal
income tax purposes of JWH Global Trust (the "Trust") as a partnership; and (ii)
the information in the Prospectus (the "Prospectus") included in the
Registration Statement under the heading "Federal Income Tax Aspects."

         In formulating our opinions, we have reviewed and relied upon the
Registration Statement and such applicable provisions of law and other documents
as we have considered necessary or desirable for purposes of the opinions
expressed herein. For purposes of our opinions, we have not made an independent
investigation of the facts set forth in such documents or the Registration
Statement. We have, consequently, assumed that the information presented therein
accurately and completely describes all material facts relevant to our opinions.
No facts have come to our attention, however, that would cause us to question
the accuracy or completeness of such facts or documents in a material way.

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         In rendering these opinions, we have assumed that the transactions
contemplated by the foregoing documents have been consummated in accordance with
the provisions thereof, and that such documents accurately reflect the material
facts of such transactions. In addition, these opinions are based upon the
assumption that the Trust will operate in the manner described in its
organizational documents and in the Registration Statement, and all terms and
provisions of such agreements and documents have been and will continue to be
complied with. Our opinions expressed herein are based on the applicable laws of
the State of Delaware, the Internal Revenue Code of 1986, as amended (the
"Code"), Treasury regulations promulgated thereunder, interpretations of the
Code and such regulations by the courts and the Internal Revenue Service, all as
they are in effect and exist at the date of this letter. It should be noted that
statutes, regulations, judicial decisions, and administrative interpretations
are subject to change at any time and, in some circumstances, with retroactive
effect. A material change that is made after the date hereof in any of the
foregoing bases for our opinions could adversely affect our conclusions.

         Based upon and subject to the foregoing, it is our opinion that:

         1.       The Trust will be treated as a partnership and will not be
treated as a "publicly traded partnership" for United Stated federal income tax
purposes, assuming that the Trust does not elect to be taxed as a corporation
and that substantially all of the gross income of the Trust for each of its
taxable years will constitute "qualifying income" within the meaning of Section
7704(d) of the Code.

         2.       The information in the Prospectus included in the Registration
Statement under the heading "TAX CONSEQUENCES," to the extent that it
constitutes matters of law or legal conclusions, has been reviewed by us and is
correct in all material respects.

         Other than as expressly stated above, we express no opinion on any
issue relating to the Trust or any investment therein. This opinion speaks as of
the date hereof and we assume no obligation to update this opinion as of any
future date. This opinion shall not be used for any purpose without our written
consent.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of the name of our firm therein under the
caption "TAX CONSEQUENCES" in the Registration Statement.

Sincerely,



/s/ Mayer, Brown, Rowe & Maw LLP