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                                                                  EXHIBIT 10.133

                                                              COPI COLORADO LOAN

                               SIXTH AMENDMENT TO
                          CREDIT AND SECURITY AGREEMENT

         THIS SIXTH AMENDMENT TO CREDIT AND SECURITY AGREEMENT (this
"Amendment") is dated as of June 28, 2001 between CRESCENT REAL ESTATE EQUITIES
LIMITED PARTNERSHIP, a Delaware limited partnership (the "Lender") and CRESCENT
OPERATING INC., a Delaware corporation (the "Borrower").

                                    RECITALS

         A. The parties executed that certain Credit and Security Agreement
dated as of September 21, 199, as mended by that certain First Amendment to
Credit and Security Agreement dated as of March 11, 1999 (collectively, the
"Original Agreement").

         B. The parties executed that Second Amendment to Credit and Security
Agreement dated as of February 1, 2000, to defer the interest payments that
would otherwise be due on the first Business Day of February, May, August and
November 2000 until the first Business Day of February 2001; the parties
executed that Third Amendment to Credit and Security Agreement dated as of
January 31, 2001, to defer until February 15, 2001, the interest payments that
would otherwise be due on February 1 ,2001; the parties executed that Fourth
Amendment to Credit and Security Agreement dated as of February 15, 2001, to
defer until March 5, 2001, the interest payments that would otherwise be due on
February 15, 2001; and the parties executed that fifth Amendment to Credit and
Security Agreement dated as of March 5, 2001, to defer until April 20, 2001, the
interest payments that would otherwise be due on March 5, 2001. The Original
Agreement, as amended by that Second Amendment, that Third Amendment, that
Fourth Amendment and that Fifth Amendment, is called the "Amended Original
Agreement." All capitalized terms not otherwise defined in this Amendment will
have the same meaning as described in the Amended Original Agreement.

         C. The parties wish to further defer the aforementioned payments until
the earlier to occur of (i) October 31, 2001 and (ii) the closing of the
transaction (the "Transaction") between Lender and Borrower pursuant to which
Lender proposed to purchase certain assets of Borrower, as evidenced by the
Agreement for the Purchase and Sale of Assets and Stock, dated as of June 28,
2001, by and among Lender, Borrower and certain of Borrower's affiliates.

         D. The parties wish to cease the accrual of interest payable pursuant
to the Amended Original Agreement as of May 1, 2001.

         In consideration of the mutual covenants set forth herein, and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto hereby agree as follows:

         1. Section 2.3. Section 2.3(c) of the Amended Original Agreement is
hereby amended by the addition of the following sentences to the end thereof:





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                                                              COPI COLORADO LOAN


         Notwithstanding the foregoing, the Borrower and the Lender hereby agree
         that the interest that would otherwise be due on the first Business Day
         of February, May, August and November 2000 and on February 1, 2001 and
         May 1, 2001 shall be deferred until, and shall be due on, the earlier
         to occur of (i) October 31, 2001 and (ii) the closing of the
         Transaction. The Borrower and the Lender hereby further agree that
         interest shall cease to accrue as of May 1, 2001.

         2. Remainder of Amended Original Agreement. Except as amended hereby,
the Amended Original Agreement shall continue in full force and effect in the
form that was effective immediately before the execution of this Amendment.

         3. Consummation of the Transaction. The terms of this Amendment shall
be subject to consummation of the Transaction on or before October 31, 2001. If
the Transaction shall not be consummated by October 31, 2001, the terms of this
Amendment shall be null and void and of no further consequence. In such event,
all interest that would have accrued under the Amended Original Agreement shall
be deemed to have continued to accrue from and after April 30, 2001, and all
such interest plus all interest deferred pursuant to this Amendment shall
immediately become due and payable in full.

         4. Counterparts. This Amendment may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
document.

         5. Binding Effect. This Amendment shall be binding upon and inure to
the benefit of the respective successors and assigns of the parties hereto.

         6. Governing Law and Severability. This Amendment shall be governed by
and construed in accordance with the laws of the State of Texas. Whenever
possible, each provision hereof shall be interpreted in such manner as to be
effective and valid under applicable law.

         7. No Waiver. The execution, delivery and effectiveness of this
Amendment shall not, except as expressly provided herein, operate as a waiver of
any right, power, or remedy of the Lender under the Original Agreement or the
Amended Original Agreement, nor constitute a waiver of any provision of the
Original Agreement or the Amended Original Agreement.



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                                                              COPI COLORADO LOAN


         IN WITNESS WHEREOF, the parties below have executed this Amendment
effective as of the date first written above.



                                CRESCENT OPERATING, INC.

                                By:
                                   ---------------------------------------
                                Name:
                                     -------------------------------------
                                Title:
                                      ------------------------------------



                                CRESCENT REAL ESTATE EQUITIES
                                LIMITED PARTNERSHIP

                                By:   Crescent Real Estate Equities, Ltd.
                                      its general partner


                                      By:
                                         ---------------------------------
                                      Name:
                                           -------------------------------
                                      Title:
                                            ------------------------------


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