June 5, 2008 Campbell & Company, Inc. Court Tower Building 210 West Pennsylvania Avenue Suite 770 Towson, MD 21204 Attn: Ms. Terry Becks Re: Management Agreement Renewals Dear Ms. Becks:

Exhibit 10.15

June 5, 2008

Xxxxxxxx & Company, Inc.
Court Tower Building
000 Xxxx Xxxxxxxxxxxx Xxxxxx
Xxxxx 000
Xxxxxx, XX 00000

Attn: Xx. Xxxxx Xxxxx

     Re: Management Agreement Renewals

Dear Xx. Xxxxx:

We are writing with respect to your management agreements concerning the commodity pools to which reference is made below (the ‘‘Management Agreements’’). We are extending the term of the Management Agreements through June 30, 2009 and all other provisions of the Management Agreements will remain unchanged.

	•		Xxxxx Xxxxxx Potomac Futures Fund L.P.
	•		Xxxxx Xxxxxx Diversified Futures Fund L.P.
	•		Xxxxx Xxxxxx Diversified Futures Fund X.X. XX
	•		Xxxxx Xxxxxx Global Diversified Futures Fund L.P.
	•		Xxxxxxx Xxxxx Xxxxxx Diversified 2000 Futures Fund L.P.
	•		CMF Xxxxxxxx Master Fund L.P.

Please acknowledge receipt of this modification by signing one copy of this letter and returning it to the attention of Xx. Xxxxxxxx Xxxxx at the address above or fax to 000-000-0000. If you have any questions I can be reached at 000-000-0000.

Very truly yours,

CITIGROUP MANAGED FUTURES LLC

By: /s/ Xxxxxxxx Xxxxx          

 Xxxxxxxx Xxxxx

 Chief Financial Officer & Director

XXXXXXXX & COMPANY, INC.

By: /s/ Xxxxxx X. Xxxxx          

Print Name: Xxxxxx X. Xxxxx

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