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                                                                    Exhibit 3.21


                            CERTIFICATE OF AMENDMENT

                                     TO THE

                       CERTIFICATE OF LIMITED PARTNERSHIP

                                       OF

                         CAPSTAR MIDLAND PARTNERS, L.P.

     The undersigned, desiring to amend the Certificate of Limited Partnership
of: CAPSTAR MIDLAND PARTNERS, L.P. pursuant to the provisions of Section 17-202
of the Revised Uniform Limited Partnership Act of the State of Delaware, does
hereby certify as follows:

     FIRST:    The name of the Limited Partnership is: CAPSTAR MIDLAND
PARTNERS, L.P.

     SECOND: Article 2 of the Certificate of Limited Partnership shall be
amended as follows:

          "2. The address of the Partnership's registered office in the state
of Delaware is Corporation Trust Center, 1209 Orange Street, Wilmington, County
of New Castle. The name of the Partnership's registered agent for service of
process in the State of Delaware at such address is: The Corporation Trust
Company.

     IN WITNESS WHEREOF, the undersigned executed this Amendment to the
Certificate of Limited Partnership on this 24th day of June, 1998.

                                                EQUISTAR ACQUISITION CORPORATION

                                                   /s/ Christopher L. Bennett
                                                --------------------------------
                                                    Christopher L. Bennett, VP
                                                By: General Partner
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                       CERTIFICATE OF LIMITED PARTNERSHIP

                                       OF

                         CAPSTAR MIDLAND PARTNERS, L.P.

     This Certificate of Limited Partnership of CapStar Midland Partners, L.P.
is duly executed and filed by EquiStar Acquisition Corporation, a Delaware
corporation to form a limited partnership under the Delaware Revised Uniform
Limited Partnership Act (6 Del.C. Section 17-101 et. seq.).

     1. The name of the limited partnership formed hereby is CapStar Midland
Partners, L.P. (the "Partnership").

     2. The address of the registered office of the Partnership in the State of
Delaware is 15 East North Street, Dover, Delaware 19901. The Partnership's
registered agent at that address is United Corporate Services, Inc.

     3. The name and mailing address of the general partner is:

               EquiStar Acquisition Corporation
               1010 Wisconsin Avenue, N.W., Suite 650
               Washington, D.C. 20007

     IN WITNESS WHEREOF, the undersigned, being the sole general partner of the
Partnership, has caused this Certificate of Limited Partnership to be duly
executed by its authorized officer who affirms that the facts set forth herein
are true under the penalties of perjury this 15th day of September, 1997.

                                        EQUISTAR ACQUISITION CORPORATION

                                        By: /s/ John E. Plunket
                                        --------------------------------
                                        Name:   John E. Plunket
                                        Title:  Vice President