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                                                                  Exhibit 10.81

                      AMENDED AND RESTATED PROMISSORY NOTE

      THIS AMENDED AND RESTATED PROMISSORY NOTE, made as of July 1, 1994 (this
"Note") by and between DIHC BOYLSTON CORP., a Georgia corporation ("Maker"),
having an office at 200 Galleria Parkway, N.W., Suite 2000, Atlanta, Georgia
30339, and STICHTING PENSIOENFONDS VOOR DE GEZONDHEID, GEESTELIJKE EN
MAATSCHAPPELIJKE BELANGEN, a foundation formed according to the laws of The
Netherlands ("Payee"), having an office at Kroostweg Number 149, Zeist, The
Netherlands.

                               W I T N E S S E T H

      WHEREAS, Payee is holder of that certain Promissory Note dated as of July
1, 1989 from Maker to Payee in the original principal amount of up to NINE
MILLION FIVE HUNDRED THOUSAND AND NO/100 DOLLARS ($9,500,000.00) (the "Boylston
Note") together with that certain Promissory Note dated as of July 1, 1989 from
DIHC St. James Corp. to Payee in the original principal amount of up to NINE
MILLION FIVE HUNDRED THOUSAND AND NO/100 DOLLARS ($9,500,000.00) (the "St. James
Note"), which was effectively assigned to Maker pursuant to the Articles of
Merger of DIHC St. James Corp. with and into DIHC Boylston Corp., dated as of
March 30, 1990, and the Plan and Agreement of Merger by which DIHC St. James
Corp. merges with and into DIHC Boylston Corp., dated as of March 30, 1990
(collectively the Boylston Note and the St. James Note shall hereinafter be
referred to as the "Original Note"), on which there is due and owing, as of July
1, 1994, the aggregate sum of EIGHTEEN MILLION FOUR HUNDRED SIXTY ONE THOUSAND
TWO HUNDRED EIGHTY THREE AND .03/100 ($18,461,283.03).

      WHEREAS, Maker and Payee have agreed to amend and restate the Original
Note in its entirety in order to (i) amend the amount outstanding thereunder,
(ii) amend the terms of payment and certain other provisions thereof, and (iii)
amend and extend the maturity date.


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      NOW, THEREFORE, Maker and Payee hereby amend and restate the Original Note
in its entirety as set forth below, effective as of this date.

      FOR VALUE RECEIVED, Maker promises to pay to the order of Payee at its
office recited above or at such other place as may be designated in writing by
the holder hereof, the principal sum of EIGHTEEN MILLION FOUR HUNDRED SIXTY ONE
THOUSAND TWO HUNDRED EIGHTY THREE AND .03/100 DOLLARS ($18,461,283.03), with
interest thereon from the date hereof at the rate of 9.25% per annum but in no
event in excess of the then maximum legal rate in Massachusetts for purposes of
determining usury.

      Equal monthly payments in the amount of One Hundred Fifty Eight Thousand
Ninety Nine and .08/100 Dollars ($158,099.08) shall be due and payable on August
1, 1994, and on the first day of each month thereafter and shall be applied
first to the payment of interest as aforesaid and the balance in reduction of
principal. The entire unpaid principal balance, together with accrued interest
thereon, shall be due and payable on June 30, 1999 (the "Maturity Date").

      Upon the request of Payee, Maker shall deliver to Payee a pledge of
Maker's partnership interest in DIHC Boylston Associates, to be secured by a
pledge, collateral assignment, UCC-I financing statement, security agreement
and any other security documents (collectively the "Security Agreement")
requested by Payee.

      Upon any default hereunder and the continuance of such default for a
period of ten (10) days after the due date or any default under the Security
Agreement, if any, and the continuance of such default after the expiration date
of any applicable grace period under any Security Agreement, Maker promises
immediately to pay the principal and interest remaining due and unpaid
hereunder, together with all costs and expenses incurred in connection with the
collection or attempted collection hereof and the protection of the security
hereof or thereof, including, without limitation, attorneys' fees, whether or
not suit is instituted. Interest shall accrue on such amounts from the date of
such default at the


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"Involuntary Rate" (as hereinafter defined) compounded monthly until the date
such amounts are paid. The "Involuntary Rate" shall be an annual rate equal to
five percent (5%) in excess of the rate charged from time to time by Morgan
Guaranty Trust Company of New York on short term (90 day) unsecured loans to its
preferred customers but in no event in excess of the then maximum legal rate in
Massachusetts for purposes of determining usury.

      Maker agrees to be bound to the extent provided in any Security Agreement
and waives and renounces any and all exemption rights and the benefit of all
valuation and appraisal privileges as against the indebtedness evidenced hereby
or any renewal or extension thereof except as set forth in any Security
Agreement, waives demand, protest, notice of nonpayment, and any and all lack of
diligence or delays in the collection or enforcement hereof, and expressly
consents to any extension of time, release of any party liable for the
indebtedness evidenced hereby, release of any of the security of this Note,
acceptance of other security thereof, or any other indulgence or forbearance
whatsoever by Payee, any one or all of which may be made without notice to Maker
or such released party or any other party.

      This Note may be prepaid in whole or in part without fee or penalty (but
with accrued interest on the amount so prepaid) upon any date for the payment of
interest, upon not less than ten (10) days' prior written notice by Maker to
Payee.

      The parties hereto have intended in good faith to comply with all
applicable usury laws. Notwithstanding anything to the contrary contained in
this Note or any other instrument evidencing, securing, or relating to this
Note, Maker shall not be obligated or required to pay interest at a rate which
would subject Payee to either criminal or civil liability. If, by the terms of
this Note, or any other instrument evidencing, securing, or relating to this
Note, Maker at any time is required or obligated to pay interest on the
principal amount of this Note in an amount or at a rate in excess of the
applicable legal maximum, the interest due to Payee shall immediately and
automatically be reduced to such maximum rate, the interest payable shall be
computed at such maximum rate, and all prior interest


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payments in excess of such lawful maximum shall be immediately and automatically
applied, and shall be deemed to have been treated as having been applied at the
time of receipt, in reduction of the principal balance due under this Note.

      The principal amount, plus accrued interest, shall become immediately due
and payable at the option of Payee upon the happening of any event by which said
balance shall or may become due and payable under the terms of any Security
Agreement (subject to any applicable grace period).

      No delays on the part of Payee in exercising any right hereunder or under
any Security Agreement or any other agreement further evidencing or securing
this Note shall operate as a waiver thereof or preclude the exercise thereof at
any time during the continuance of any default or during the continuance of a
subsequent default.

      This Note may not be modified or terminated orally. This Note may be
assigned by Payee, in its sole discretion, without the consent of Maker. This
Note shall be construed and enforced in accordance with the law of
Massachusetts.

      IN WITNESS WHEREOF, Maker has executed this Note as of the 1st day of
July, 1994.

ATTEST:                             DIHC BOYLSTON CORP.


[signature illegible]               By: /s/ Robert T. Sorrentino
----------------------------           ----------------------------
                                       Robert T. Sorrentino
                                       Vice President


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COUNTY OF COBB    )
                  : ss.:
STATE OF GEORGIA  )

      BEFORE ME the undersigned authority personally appeared on this day Robert
T. Sorrentino, to me personally known, who being by me duly sworn did depose and
say that he is Vice President of DIHC Boylston Corp., the corporation described
in and which executed the foregoing instrument; that he acknowledged execution
of said instrument to be the voluntary act and deed of said corporation by order
of the Board of Directors of said corporation.

      WITNESS my hand and official seal this 14th day of October, 1998


                                     /s/ Brenda S. Leach
                                     ------------------------
                                     Notary Public

My Commission Expires:

Notary Public, DeKalb County, Georgia
My Commission Expires July 2, 2000


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