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                                                                   EXHIBIT 10.65

                                                              Four Seasons Hotel
                                                                  Houston, Texas


                     AMENDED AND RESTATED GUARANTY OF LEASE


         This AMENDED AND RESTATED GUARANTY OF LEASE ("Guaranty") is executed as
of December 31, 1998 by CRESCENT OPERATING, INC., a Delaware corporation
("Guarantor"), for the benefit of CRESCENT REAL ESTATE EQUITIES LIMITED
PARTNERSHIP, a Delaware limited partnership ("Lessor").

                                 R E C I T A L S

         A.       COI HOTEL GROUP, INC., a Texas corporation ("Lessee"), as 
lessee, has entered a Lease Agreement (the "Lease") with Lessor dated as of
September 22, 1997 with respect to the land, buildings, improvements and
fixtures located in Houston, Harris County, Texas, commonly known as the Four
Seasons Hotel (the "Leased Property");

         B.       Guarantor executed that certain Guaranty dated of even date 
with the Lease pursuant to which Guarantor unconditionally guaranteed the
payment and performance of the obligations of Lessee under the Lease (the
"Original Lease"); and

         C.       Lessor and Lessee are entering into an amendment to the Lease
to be effective as of the date hereof and in connection with such amendment,
Guarantor and Lessee have agreed to certain changes to the Original Guaranty and
wish to amend and restate the Original Guaranty in its entirety to reflect
Guarantor's agreement to unconditionally guarantee the payment and performance
of the Guaranteed Obligations (as defined in Section 1.2 below), subject to the
limitations and terms set forth in this Guaranty; and

         D.       Guarantor is the owner of a direct or indirect interest in 
Lessee, and Guarantor will directly benefit from the amendments to the Lease
described above.

                                A G R E E M E N T

         NOW, THEREFORE, as an inducement to Lessor to enter into the Lease with
Lessee, and for other good and valuable consideration, the receipt and legal
sufficiency of which are hereby acknowledged, the parties agree as follows:

                                   ARTICLE I

                          NATURE AND SCOPE OF GUARANTY

         1.1      Guaranty of Obligation.

                  (a)     Subject to the limitations set forth in Section 1.1(b)
         hereof, Guarantor irrevocably and unconditionally guarantees to Lessor
         (and its successors and assigns), the 


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         payment and performance of the Guaranteed Obligations as and when the
         same shall be due and payable. Guarantor irrevocably and
         unconditionally agrees that it is liable for the Guaranteed Obligations
         as a primary obligor, and that it shall fully perform each and every
         term and provision hereof.

                  (b)     Anything in this Guaranty to the contrary 
         notwithstanding, the right of recovery by Lessor against Guarantor
         under this Guaranty is limited to Guarantor's interests in Lessee and
         the lessees under the leases listed on Exhibit A attached hereto and
         made a part hereof, and such parties permitted successors and assigns
         (whether by operation of law or otherwise). Lessor shall not look to
         any other property or asset of Guarantor in seeking to enforce
         Guarantor's obligations under this Guaranty or to satisfy any judgement
         for Guarantor's failure to perform its obligations under this Guaranty.

         1.2      Definition of Guaranteed Obligations. As used herein, the term
"Guaranteed Obligations" shall mean all of the obligations and liabilities of
Lessee under the Lease, including without limitation, the obligation to pay all
Base Rent, Percentage Rent, and Additional Charges (as those terms are defined
in the Lease) as and when due.

         1.3      Nature of Guaranty. This Guaranty is an irrevocable, absolute,
continuing guaranty of payment and performance and is not a guaranty of
collection. This Guaranty may not be revoked by Guarantor and shall continue to
be effective with respect to any Guaranteed Obligations arising or created after
any attempted revocation by Guarantor. The fact that at any time or from time to
time the Guaranteed Obligations may be increased or reduced shall not release or
discharge the obligation of Guarantor to Lessor with respect to Guaranteed
Obligations. This Guaranty may be enforced by Lessor and any subsequent owner of
Lessor's interest under the Lease.

         1.4      Payment by Guarantor. If all or any part of the Guaranteed
Obligations is not paid when due, Guarantor shall immediately upon demand by
Lessor pay in lawful money of the United States of America the amount due on the
Guaranteed Obligations to Lessor at Lessor's address as set forth herein. Such
demand(s) may be made at any time coincident with or after the time for payment
of all or part of the Guaranteed Obligations, and may be made from time to time
with respect to the same or different items of Guaranteed Obligations. Such
demand shall be deemed made, given and received in accordance with the notice
provisions hereof.

         1.5      No Duty to Pursue Others. It shall not be necessary for Lessor
(and Guarantor hereby waives any rights which Guarantor may have to require
Lessor), in order to enforce such payment by Guarantor, first to (i) institute
suit or exhaust its remedies against Lessee or others liable under the Lease or
the Guaranteed Obligations or any other person, (ii) enforce Lessor's rights
against any collateral which shall ever have been given to secure Lessee's
obligations under the Lease, (iii) enforce Lessor's rights against any other
guarantors of the Guaranteed Obligations, (iv) join Lessee or any others liable
on the Guaranteed Obligations in any action seeking to enforce this Guaranty, or
(v) resort to any other means of obtaining payment of the Guaranteed
Obligations. Lessor shall not be required to mitigate damages or take any other
action to reduce, collect or enforce the Guaranteed Obligations.


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         1.6      Waivers. Guarantor agrees to the provisions of the Lease, and
hereby waives notice of (i) acceptance of this Guaranty, (ii) any amendment or
extension of the Lease, (iii) the occurrence of any breach by Lessee or Event of
Default as defined in the Lease, (iv) Lessor's transfer or disposition of its
interest under the Lease, or any part thereof, or (v) any other action at any
time taken or omitted by Lessor, and, generally, all demands and notices of
every kind in connection with this Guaranty, the Lease, or relating to any of
the Guaranteed Obligations.

         1.7      Payment of Expenses. If Guarantor fails to timely perform any
provisions of this Guaranty, Guarantor shall, immediately upon demand by Lessor,
pay Lessor all costs and expenses (including court costs and reasonable
attorneys' fees) incurred by Lessor in the enforcement hereof or the
preservation of Lessor's rights hereunder. The covenant contained in this
section shall survive the payment and performance of the Guaranteed Obligations.

         1.8      Effect of Bankruptcy. If, pursuant to any insolvency, 
bankruptcy, reorganization, receivership or other debtor relief law, or any
judgment, order or decision thereunder, Lessor must rescind or restore any
payment, or any part thereof, received by Lessor in satisfaction of the
Guaranteed Obligations, as set forth herein, any prior release or discharge from
the terms of this Guaranty given to Guarantor by Lessor shall be without effect,
and this Guaranty shall remain in full force and effect. Lessee and Guarantor
intend that Guarantor's obligations hereunder shall not be discharged except by
Guarantor's performance of such obligations and then only to the extent of such
performance.

         1.9      Deferment of Rights of Subrogation, Reimbursement and 
Contribution.

                  (a)     Notwithstanding any payment or payments made by 
         Guarantor hereunder, Guarantor will not assert or exercise any right of
         Lessor or of Guarantor against Lessee to recover the amount of any
         payment made by Guarantor to Lessor by way of subrogation,
         reimbursement, contribution, indemnity, or otherwise arising by
         contract or operation of law, and Guarantor shall not have any right of
         recourse to or any claim against assets or property of Lessee, whether
         or not the obligations of Lessee have been satisfied, all of rights
         being herein expressly waived by Guarantor. If any amount shall
         nevertheless be paid to Guarantor by Lessee prior to payment in full of
         the Obligations (hereinafter defined), such amount shall be held in
         trust for the benefit of Lessor and shall forthwith be paid to Lessor
         to be credited and applied to the Obligations, whether matured or
         unmatured. The provisions of this paragraph shall survive the
         termination of this Guaranty, and any satisfaction and discharge of
         Lessee by virtue of any payment, court order or any applicable law.

                  (b)     Notwithstanding the provisions of Section 1.9(a),
         Guarantor shall be entitled to (i) all rights of subrogation otherwise
         provided by applicable law in respect of any payment it may make or be
         obligated to make under this Guaranty and (ii) all claims it would have
         against Guarantor in the absence of Section 1.9(a) and to assert and
         enforce same, in each case on and after, but at no time prior to, the
         date (the "Subrogation Trigger Date") which is 91 days after the date
         on which all sums owed to Lessor under the Lease (the "Obligations")
         have been paid in full, if and only if the existence of Guarantor's
         rights under this Section 1.10(b) would not make Guarantor a creditor
         (as defined in the United 


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         States Bankruptcy Code [the "Bankruptcy Code"]) of Lessee or any other
         Guarantor in any insolvency, bankruptcy, reorganization or similar
         proceeding commenced on or prior to the Subrogation Trigger Date.

         1.10     Bankruptcy Code Waiver. The parties intend that Guarantor 
shall not be deemed to be a "creditor" (as defined in Section 101 of the
Bankruptcy Code) of Lessee by reason of the existence of this Guaranty, in the
event that Lessee becomes a debtor in any proceeding under the Bankruptcy Code,
and in connection herewith, Guarantor waives any such right as a "creditor"
under the Bankruptcy Code. After Lessee's obligations under the Lease are
discharged in full and there shall be no obligations or liabilities under this
Guaranty outstanding, this waiver shall be deemed to be terminated.

         1.11     Lessee. The term "Lessee" as used herein shall include any new
or successor corporation, association, partnership (general or limited), joint
venture, trust or other individual or organization formed as a result of any
merger, reorganization, sale, transfer, devise, gift or bequest of Lessee or any
interest in Lessee.

                                   ARTICLE II

                      EVENTS AND CIRCUMSTANCES NOT REDUCING
                     OR DISCHARGING GUARANTOR'S OBLIGATIONS

         Guarantor's obligations under this Guaranty shall not be released,
diminished, impaired, reduced or adversely affected by any of the following, and
Guarantor waives any common law, equitable, statutory or other rights (including
without limitation rights to notice) which Guarantor might otherwise have as a
result any of the following:

                  (a)     Modifications. Any renewal, extension, or modification
         of all or any part of the Guaranteed Obligations or the Lease; provided
         Guarantor is notified of same.

                  (b)     Adjustment. Any adjustment, indulgence, forbearance or
         compromise that might be granted or given by Lessor to Lessee or any
         Guarantor.

                  (c)     Condition of Lessee or Guarantor. The insolvency,
         bankruptcy, arrangement, adjustment, composition, liquidation,
         disability, dissolution or lack of power of Lessee, Guarantor or any
         other party at any time liable for the payment of all or part of the
         Guaranteed Obligations; or any dissolution of Lessee or Guarantor, or
         any sale, lease or transfer of any or all of the assets of Lessee or
         Guarantor, or any changes in the shareholders, partners or members of
         Lessee or Guarantor; or any reorganization of Lessee or Guarantor.

                  (d)     Invalidity of Guaranteed Obligations. The invalidity,
         illegality or unenforceability of all or any part of the Guaranteed
         Obligations, or any document or agreement executed in connection with
         the Guaranteed Obligations, for any reason whatsoever, including
         without limitation the fact that (i) the Guaranteed Obligations, or any
         part thereof, exceeds the amount permitted by law, (ii) the act of
         creating the Guaranteed 


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         Obligations or any part thereof is ultra vires, (iii) the officers or
         representatives executing the Lease or otherwise creating the
         Guaranteed Obligations acted in excess of their authority, (iv) the
         Guaranteed Obligations violate applicable usury laws, (v) Lessee has
         valid defenses, claims or offsets (whether at law, in equity or by
         agreement) which render the Guaranteed Obligations wholly or partially
         uncollectible from Lessee, (vi) the creation, performance or repayment
         of the Guaranteed Obligations (or the execution, delivery and
         performance of any document or instrument representing part of the
         Guaranteed Obligations or executed in connection with the Guaranteed
         Obligations, or given to secure the repayment of the Guaranteed
         Obligations) is illegal, uncollectible or unenforceable, or (vii) the
         Lease has been forged or otherwise are irregular or not genuine or
         authentic, it being agreed that Guarantor shall remain liable hereon
         regardless of whether Lessee or any other person be found not liable on
         the Guaranteed Obligations or any part thereof for any reason.

                  (e)     Release of Obligors. Any full or partial release of 
         the liability of Lessee on the Guaranteed Obligations, or any part
         thereof, or of any co-guarantors, or any other person or entity now or
         hereafter liable, whether directly or indirectly, jointly, severally,
         or jointly and severally, to pay, perform, guarantee or assure the
         payment of the Guaranteed Obligations, or any part thereof, it being
         recognized, acknowledged and agreed by Guarantor that Guarantor may be
         required to pay the Guaranteed Obligations in full without assistance
         or support of any other party, and Guarantor has not been induced to
         enter into this Guaranty on the basis of a contemplation, belief,
         understanding or agreement that other parties will be liable to pay or
         perform the Guaranteed Obligations, or that Lessor will look to other
         parties to pay or perform the Guaranteed Obligations.

                  (f)     Offset. The Lease, the Guaranteed Obligations and the
         liabilities and obligations of Guarantor to Lessor hereunder, shall not
         be reduced, discharged or released because of or by reason of any
         existing or future right of offset, claim or defense of Lessee against
         Lessor, or any other party, or against payment of the Guaranteed
         Obligations, whether such right of offset, claim or defense arises in
         connection with the Guaranteed Obligations (or the transactions
         creating the Guaranteed Obligations) or otherwise.

                  (g)     Merger. The reorganization, merger or consolidation of
         Lessee into or with any other corporation or entity.

                  (h)     Preference. Any payment by Lessee to Lessor is held to
         constitute a preference under bankruptcy laws, or for any reason Lessor
         is required to refund such payment or pay such amount to Lessee or
         someone else.

                  (i)     Other Actions Taken or Omitted. Any other action taken
         or omitted to be taken with respect to the Lease, the Guaranteed
         Obligations, whether or not such action or omission prejudices
         Guarantor or increases the likelihood that Guarantor will be required
         to pay the Guaranteed Obligations pursuant to the terms hereof, it is
         the unambiguous and unequivocal intention of Guarantor that Guarantor
         shall be obligated to pay the Guaranteed Obligations when due,
         notwithstanding any occurrence, circumstance, event, action, or
         omission whatsoever, whether or not contemplated, and whether or not
         otherwise or 

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         particularly described herein, which obligation shall be deemed
         satisfied only upon the full and final payment and satisfaction of the
         Guaranteed Obligations.

                                   ARTICLE III

                         REPRESENTATIONS AND WARRANTIES

         3.1     Representations. To induce Lessor to enter into the Lease with
Lessee, Guarantor represents and warrants to Lessor as follows:

                  (a)     Benefit. Guarantor is an affiliate of Lessee, is the 
         owner of a direct or indirect interest in Lessee, and has received, or
         will receive, direct or indirect benefit from the making of this
         Guaranty with respect to the Guaranteed Obligations.

                  (b)     Familiarity and Reliance. Guarantor is familiar with,
         and has independently reviewed books and records regarding, the
         financial condition of Lessee; however, Guarantor is not relying on
         such financial condition or the collateral as an inducement to enter
         into this Guaranty.

                  (c)     No Representation by Lessor. Neither Lessor nor any
         other party has made any representation, warranty or statement to
         Guarantor in order to induce Guarantor to execute this Guaranty.

                  (d)     Guarantor's Financial Condition. As of the date 
         hereof, and after giving effect to this Guaranty and the contingent
         obligation evidenced hereby, Guarantor is, and will be, solvent, and
         has and will have assets which, fairly valued, exceed its obligations,
         liabilities (including contingent liabilities) and debts, and has and
         will have property and assets sufficient to satisfy and repay its
         obligations and liabilities.

                  (e)     Legality. The execution, delivery and performance by
         Guarantor of this Guaranty and the consummation of the transactions
         contemplated hereunder do not, and will not, contravene or conflict
         with any law, statute or regulation whatsoever to which Guarantor is
         subject or constitute a default (or an event which with notice or lapse
         of time or both would constitute a default) under, or result in the
         breach of, any indenture, mortgage, deed of trust, charge, lien, or any
         contract, agreement or other instrument to which Guarantor is a party
         or which may be applicable to Guarantor. This Guaranty is a legal and
         binding obligation of Guarantor and is enforceable in accordance with
         its terms, except as limited by bankruptcy, insolvency or other laws of
         general application relating to the enforcement of creditors' rights.

                  (f)     Review of Documents. Guarantor has examined the Lease.

         3.2      Survival. All representations and warranties made by Guarantor
herein shall survive the execution hereof.


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                                   ARTICLE IV

                      SUBORDINATION OF CERTAIN INDEBTEDNESS

         4.1      Subordination of All Guarantor Claims. As used herein, the 
term "Guarantor Claims" shall mean all debts and liabilities of Lessee to
Guarantor, whether such debts and liabilities now exist or are hereafter
incurred or arise, or whether the obligations of Lessee thereon be direct,
contingent, primary, secondary, several, joint and several, or otherwise, and
irrespective of whether such debts or liabilities be evidenced by note,
contract, open account, or otherwise, and irrespective of the person or persons
in whose favor such debts or liabilities may, at their inception, have been, or
may hereafter be created, or the manner in which they have been or may hereafter
be acquired by Guarantor. The Guarantor Claims shall include without limitation
all rights and claims of Guarantor against Lessee (arising as a result of
subrogation or otherwise) as a result of Guarantor's payment of all or a portion
of the Guaranteed Obligations to the extent the provisions of Article II(f)
hereof are unenforceable. Upon the occurrence of an Event of Default or the
occurrence of an event which would, with the giving of notice or the passage of
time, or both, constitute an Event of Default, Guarantor shall not receive or
collect, directly or indirectly, from Lessee or any other party any amount upon
the Guarantor Claims.

         4.2      Claims in Bankruptcy. In the event of receivership, 
bankruptcy, reorganization, arrangement, debtor's relief, or other insolvency
proceedings involving Guarantor as debtor, Lessor shall have the right to prove
its claim in any such proceeding so as to establish its rights hereunder and
receive directly from the receiver, trustee or other court custodian dividends
and payments which would otherwise be payable upon Guarantor Claims. Guarantor
assigns such dividends and payments to Lessor. Should Lessor receive, for
application upon the Guaranteed Obligations, any such dividend or payment which
is otherwise payable to Guarantor, and which, as between Lessee and Guarantor,
shall constitute a credit upon the Guarantor Claims, then upon payment to Lessor
in full of the Guaranteed Obligations, Guarantor shall become subrogated to the
rights of Lessor to the extent that such payments to Lessor on the Guarantor
Claims have contributed toward the liquidation of the Guaranteed Obligations,
and such subrogation shall be with respect to that proportion of the Guaranteed
Obligations which would have been unpaid if Lessor had not received dividends or
payments upon the Guarantor Claims.

         4.3      Payments Held in Trust. Notwithstanding anything to the 
contrary in this Guaranty, if Guarantor should receive any funds, payments,
claims or distributions which are prohibited by this Guaranty, Guarantor agrees
to hold in trust for Lessor an amount equal to the amount of all funds,
payments, claims or distributions so received, and agrees that it shall have
absolutely no dominion over the amount of such funds, payments, claims or
distributions so received except to pay them promptly to Lessor, and Guarantor
covenants promptly to pay the same to Lessor.

         4.4      Liens Subordinate. Any liens, security interests, judgment 
liens, charges or other encumbrances upon Lessee's assets securing payment of
the Guarantor Claims shall be and remain inferior and subordinate to any liens,
security interests, judgment liens, charges or other encumbrances upon Lessee's
assets securing payment of the Guaranteed Obligations, regardless of whether
such encumbrances in favor of Guarantor or Lessor presently exist or are
hereafter created or attach. Without the prior written consent of Lessor,
Guarantor shall not (a) exercise or enforce any creditor's right it may have
against Lessee, or (b) foreclose, repossess, sequester or otherwise 


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take steps or institute any action or proceedings (judicial or otherwise,
including without limitation the commencement of, or joinder in, any
liquidation, bankruptcy, rearrangement, debtor's relief or insolvency
proceeding) to enforce any liens, mortgages, deeds of trust, security interest,
collateral rights, judgments or other encumbrances on assets of Lessee held by
Guarantor.

                                    ARTICLE V

                                  MISCELLANEOUS

         5.1      Waiver. No failure to exercise, and no delay in exercising, 
on the part of Lessor, any right hereunder shall operate as a waiver thereof,
nor shall any single or partial exercise thereof preclude any other or further
exercise thereof or the exercise of any other right. The rights of Lessor
hereunder shall be in addition to all other rights provided by law. No
modification or waiver of any provision of this Guaranty, nor consent to
departure therefrom, shall be effective unless in writing and no such consent or
waiver shall extend beyond the particular case and purpose involved. No notice
or demand given in any case shall constitute a waiver of the right to take other
action in the same, similar or other instances without such notice or demand.

         5.2      Notices. Any notice, demand, statement, request or consent 
made hereunder shall be in writing and shall be deemed to be received by the
addressee on the day such notice is tendered to a nationally recognized
overnight delivery service or on the third day following the day such notice is
deposited with the United States Postal Service first class certified mail,
return receipt requested, in either instance, addressed to the address, as set
forth below, of the party to whom such notice is to be given, or to such other
address as either party shall in like manner designate in writing. The addresses
of the parties are as follows:

                  Guarantor:

                  Crescent Operating, Inc.
                  306 West 7th Street, Suite 1025
                  Fort Worth, Texas 76102
                  Attention:  Jeffrey L. Stevens

                  Lessor:

                  Crescent Real Estate Equities Limited Partnership
                  777 Main Street, Suite 2100
                  Fort Worth, Texas 76102
                  Attention:  Gerald W. Haddock, President and 
                              Chief Executive Officer

         5.3      Governing Law; Jurisdiction. This Guaranty shall be governed 
by and construed in accordance with the laws of the State in which the Leased
Property is located and the applicable laws of the United States of America.
Guarantor hereby irrevocably submits to the jurisdiction of any court of
competent jurisdiction located in the state in which the Leased Property is
located in connection with any proceeding out of or relating to this Guaranty.


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<PAGE>   9

         5.4      Invalid Provisions. If any provision of this Guaranty is held
to be illegal, invalid, or unenforceable under present or future laws effective
during the term of this Guaranty, such provision shall be fully severable and
this Guaranty shall be construed and enforced as if such illegal, invalid or
unenforceable provision had never comprised a part of this Guaranty, and the
remaining provisions of this Guaranty shall remain in full force and effect and
shall not be affected by the illegal, invalid or unenforceable provision or by
its severance from this Guaranty, unless such continued effectiveness of this
Guaranty, as modified, would be contrary to the basic understandings and
intentions of the parties as expressed herein.

         5.5      Amendments. This Guaranty may be amended only by an instrument
in writing executed by the party or an authorized representative of the party
against whom such amendment is sought to be enforced.

         5.6      Parties Bound; Assignment. This Guaranty shall be binding upon
and inure to the benefit of the parties hereto and their respective successors,
assigns and legal representatives; provided, however, that Guarantor may not,
without the prior written consent of Lessor, assign any of its rights, powers,
duties or obligations hereunder.

         5.7      Headings. Section headings are for convenience of reference 
only and shall in no way affect the interpretation of this Guaranty.

         5.8      Recitals. The recital and introductory paragraphs hereof are
a part hereof, form a basis for this Guaranty and shall be considered prima
facie evidence of the facts and documents referred to therein.

         5.9      Counterparts. This Guaranty may be executed in as many 
counterparts as may be convenient or required. It shall not be necessary that
the signature or acknowledgment of, or on behalf of, each party, or that the
signature of all persons required to bind any party, or the acknowledgment of
such party, appear on each counterpart. All counterparts shall collectively
constitute a single instrument. It shall not be necessary in making proof of
this Guaranty to produce or account for more than a single counterpart
containing the respective signatures of, or on behalf of, and the respective
acknowledgments of, each of the parties hereto. Any signature or acknowledgment
page to any counterpart may be detached from such counterpart without impairing
the legal effect of the signatures or acknowledgments thereon and thereafter
attached to another counterpart identical thereto except having attached to it
additional signature or acknowledgment pages.

         5.10     Rights and Remedies. The rights of Lessor hereunder shall be
cumulative of any and all other rights that Lessor may ever have against
Guarantor. The exercise by Lessor of any right or remedy hereunder or under any
other instrument, or at law or in equity, shall not preclude the concurrent or
subsequent exercise of any other right or remedy.

         5.11     ENTIRETY. THIS GUARANTY EMBODIES THE FINAL, ENTIRE AGREEMENT 
OF GUARANTOR AND LESSOR WITH RESPECT TO GUARANTOR'S GUARANTY OF THE GUARANTEED
OBLIGATIONS AND SUPERSEDES ANY AND ALL PRIOR COMMITMENTS, AGREEMENTS,
REPRESENTATIONS, AND 


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<PAGE>   10

UNDERSTANDINGS, WHETHER WRITTEN OR ORAL, RELATING TO THE SUBJECT MATTER HEREOF.
THIS GUARANTY IS INTENDED BY GUARANTOR AND LESSOR AS A FINAL AND COMPLETE
EXPRESSION OF THE TERMS OF THE GUARANTY, AND NO COURSE OF DEALING BETWEEN
GUARANTOR AND LESSOR, NO COURSE OF PERFORMANCE, NO TRADE PRACTICES, AND NO
EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OR DISCUSSIONS
OR OTHER EXTRINSIC EVIDENCE OF ANY NATURE SHALL BE USED TO CONTRADICT, VARY,
SUPPLEMENT OR MODIFY ANY TERM OF THIS GUARANTY AGREEMENT. THERE ARE NO ORAL
AGREEMENTS BETWEEN GUARANTOR AND LESSOR.

         5.12     Special State Provisions (Texas). This Guaranty shall be 
effective as a waiver of, and Guarantor expressly waives, any and all rights to
which Guarantor may otherwise have been entitled under any suretyship laws in
effect from time to time, including (without limitation) any rights pursuant to
Rule 31 of the Texas Rules of Civil Procedure, Section 17.001 of the Texas Civil
Practice and Remedies Code, and Chapter 34 of the Texas Business and Commerce
Code.


                     [REST OF PAGE INTENTIONALLY LEFT BLANK]



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<PAGE>   11



         EXECUTED as of the day and year first above written.


                             GUARANTOR:

                             CRESCENT OPERATING, INC., a Delaware Corporation


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









<PAGE>   12

                                    EXHIBIT A

                    TO AMENDED AND RESTATED GUARANTY OF LEASE


1.       Lease Agreement covering a hotel facility and related assets located in
         Bernalillo County, New Mexico, and known as "Hyatt Regency Albuquerque"
         dated as of December 19, 1995, the lessee's interest under which is
         currently held by ROSESTAR SOUTHWEST, LLC, a Delaware limited liability
         company, and the lessor's interest under which is currently held by
         CRESCENT REAL ESTATE FUNDING II, L.P, a Delaware limited partnership,
         as such Lease Agreement is or has been amended and assigned from time
         to time.

2.       Amended and Restated Lease Agreement covering a hotel facility and
         related assets located in Eagle County, Colorado, and known as the
         "Hyatt Regency Beaver Creek", dated as of January 1, 1996, the lessee's
         interest under which is currently held by ROSESTAR SOUTHWEST, LLC, a
         Delaware limited liability company, and the lessor's interest under
         which is currently held by CRESCENT REAL ESTATE FUNDING II, L.P, a
         Delaware limited partnership, as such Amended and Restated Lease
         Agreement is or has been amended and assigned from time to time.

3.       Lease Agreement covering a resort facility and related assets located
         in Berkshire County, Massachusetts, and known as the "Canyon
         Ranch-Lenox", dated as of December 11, 1996, the lessee's interest
         under which is currently held by WINE COUNTRY HOTEL, LLC, a Delaware
         limited liability company, d/b/a VINTAGE RESORTS, LLC, and the lessor's
         interest under which is currently held by CRESCENT REAL ESTATE FUNDING
         VI, L.P, a Delaware limited partnership, as such Lease Agreement is or
         has been amended and assigned from time to time.

4.       Lease Agreement covering a hotel facility/resort and related assets
         located in Sonoma County, California, and known as the "Sonoma Mission
         Inn and Spa", dated as of November 18, 1996, between WINE COUNTRY
         HOTEL, LLC, a Delaware limited liability company, as lessee, and
         CRESCENT REAL ESTATE EQUITIES LIMITED PARTNERSHIP, a Delaware limited
         partnership, as lessor, as such Lease Agreement is amended and assigned
         from time to time.

5.       Lease Agreement covering a resort facility and related assets located
         in Pima County, Arizona, and known as the "Canyon Ranch-Tucson", dated
         as of July 26, 1996, the lessee's interest under which is currently
         held by CANYON RANCH LEASING, L.L.C., an Arizona limited liability
         company, and the lessor's interest under which is currently held by
         CRESCENT REAL ESTATE EQUITIES LIMITED PARTNERSHIP, a Delaware limited
         partnership, as such Lease Agreement is or has been amended and
         assigned from time to time.


                               Exhibit A - Page 1

<PAGE>   13

6.       Amended and Restated Lease Agreement covering a hotel facility and
         related assets located in Denver County, Colorado, and known as the
         "Denver Marriott City Center", dated as of June 30, 1995, between
         ROSESTAR MANAGEMENT, LLC, a Delaware limited liability company, as
         lessee, and CRESCENT REAL ESTATE EQUITIES LIMITED PARTNERSHIP, a
         Delaware limited partnership, as lessor, as such Amended and Restated
         Lease Agreement is amended and assigned from time to time.

7.       Lease Agreement covering a golf club and related facilities located in
         Sonoma County, California, and known as the "Sonoma Golf Club", dated
         as of October 13, 1998, between WINE COUNTRY GOLF CLUB, INC., a Texas
         corporation, as lessee, and CRESCENT REAL ESTATE EQUITIES LIMITED
         PARTNERSHIP, a Delaware limited partnership, as lessor, as such Lease
         Agreement is amended and assigned from time to time.

8.       Lease Agreement covering a hotel facility and related assets located in
         Monterey County, California, and known as the "Ventana Inn or the
         Ventana Country Inn", dated as of December 19, 1997, between WINE
         COUNTRY HOTEL, LLC, a Delaware limited liability company, as lessee,
         and CRESCENT REAL ESTATE EQUITIES LIMITED PARTNERSHIP, a Delaware
         limited partnership, as lessor, as such Lease Agreement is amended and
         assigned from time to time.





                               Exhibit A - Page 2