Exhibit 10.49a

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                                                       Dated as of June 30, 2004

                         MORTGAGE MODIFICATION AGREEMENT


                                     between


                           HEATHCOTE ASSOCIATES, L.P.,
                         a New York limited partnership,
                                   Mortgagor,


                                       and


                             FLEET NATIONAL BANK, as
            Administrative Agent for Lenders (as hereinafter defined)
          (together with its successors in such capacity, "Mortgagee")

This instrument affects real and personal property situated at the northeast
corner of Shelbourne Road and Interstate 189 in South Burlington, Vermont.

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                              RECORD AND RETURN TO:
                                Schiff Hardin LLP
                          623 Fifth Avenue, 28th Floor
                            New York, New York 10022
                         Attention: Paul G. Mackey, Esq.



                         MORTGAGE MODIFICATION AGREEMENT

                MORTGAGE MODIFICATION AGREEMENT dated this 30th day of June,
2004 between HEATHCOTE ASSOCIATES, L.P. ("Mortgagor") and FLEET NATIONAL BANK,
as Administrative Agent ("Mortgagee").

                              W I T N E S S E T H:

                WHEREAS, Mortgagee is now the lawful owner and holder of the
note (collectively, the "Original Note") secured by that certain Mortgage,
Assignment of Leases and Rents and Security Agreement from Mortgagor to
Mortgagee dated as of April 16, 2002 and recorded in the Office of the Suffolk
County Clerk, New York on April 17, 2002 in Volume 548 at page 267 (the
"Original Mortgage");

                WHEREAS, the maximum principal amount which is or under any
contingency may be secured by the Original Mortgage prior to the effect of this
Mortgage Modification Agreement is $9,350,000, plus interest thereon and all
additional interest and late payment and prepayment charges in respect thereof,
plus all amounts expended by Mortgagee following a default thereunder in respect
of insurance premiums and real estate taxes, and all legal costs or expenses of
collection of the note(s) secured thereby or of the defense or prosecution of
the rights and lien created thereby;

                WHEREAS, Mortgagee, Mortgagor, RD Abington Associates Limited
Partnership ("Abington Mortgagor"), RD Methuen Associates Limited Partnership
("Methuen Mortgagor"), RD Branch Associates, L.P. ("Branch Mortgagor") and
Acadia Town Line, LLC ("Town Line Mortgagor") have entered into that certain
Amended and Restated Term Loan Agreement dated as of the date hereof (the
"Amended and Restated Loan Agreement"), which Amended and Restated Loan
Agreement consolidates the Original Note with certain other notes and extends,
amends and restates the terms thereof in their entirety;

                WHEREAS, the notes consolidated and modified pursuant to the
Amended and Restated Loan Agreement evidence a consolidated indebtedness (the
"Consolidated Indebtedness") in the principal amount of up to $45,900,000 and
Mortgagor and Mortgagee have agreed to increase the Mortgage Amount of the
Original Mortgage to $45,900,000 in order that the Original Mortgage, as
modified hereby, shall secure the entire Consolidated Indebtedness;

                WHEREAS, the Original Mortgage is a first priority mortgage
encumbering the property described on SCHEDULE A attached hereto and made a part
hereof (the "Premises");

                WHEREAS, Mortgagor is the lawful owner of the Premises; and

                WHEREAS, Mortgagee and Mortgagor have agreed to modify the terms
of the Original Mortgage in the manner hereinafter set forth.



                NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein expressed, the parties hereto covenant and agree as follows:

                1.      The definition of the term "Mortgage Amount" in the
Original Mortgage is hereby changed to $45,900,000 such that the principal
amount secured by the Original Mortgage as modified hereby is increased to
$45,900,000 or so much thereof as is advanced and outstanding pursuant to the
terms of the Amended and Restated Loan Agreement. Capitalized terms used in the
Original Mortgage and not otherwise defined shall have the meanings attributed
to them in the Amended and Restated Loan Agreement.

                2.      The following definitions of the terms "Hedging
Agreement" and "Loan Note" are hereby added to the Original Mortgage:

                " 'Hedging Agreement' shall mean, collectively, the ISDA Master
        Agreement and/or other documentation with respect to an interest rate
        hedging transaction entered into by and between Acadia Realty Limited
        Partnership and Counterparty dated as of August 23, 2001, as assigned to
        Abington Mortgagor, Methuen Mortgagor and/or Branch Mortgagor by Acadia
        Realty Limited Partnership, as well as any interest rate swap, cap or
        other interest rate protection agreement between Mortgagor and
        Counterparty, as any of the same may be amended, modified or
        supplemented from time to time, including any and all "confirmations"
        under any thereof."

                " 'Loan Note' shall mean the Notes, as defined in the Amended
        and Restated Loan Agreement, as the same may hereafter be amended,
        modified, extended, severed, assigned, consolidated with other notes,
        renewed, replaced or restated."

                3.      As used in the Original Mortgage, the term "Loan
Agreement" shall mean the Amended and Restated Loan Agreement, as the same may
be modified, amended or supplemented from time to time and the term "Note" shall
mean, collectively, the Loan Note and the Hedging Agreement.

                4.      Anything to the contrary contained herein
notwithstanding, the maximum principal amount which is or under any contingency
may be secured by the Original Mortgage as modified hereby is $45,900,000, plus
interest thereon and all additional interest and late payment and prepayment
charges in respect thereof, plus all amounts expended by Mortgagee following a
default thereunder in respect of insurance premiums and real estate taxes, and
all legal costs or expenses of collection of the note(s) secured thereby or of
the defense or prosecution of the rights and lien created thereby.

                5.      Mortgagor represents and warrants that there exist no
defenses, offsets or counterclaims with respect to its obligations under the
Original Mortgage, as modified hereby, or under the Note.

                6.      Except as modified hereby the Original Mortgage remains
unmodified and in full force and effect.

                                        2


                7.      The terms and provisions hereof shall be binding upon
and inure to the benefit of the parties hereto and their heirs, representatives,
successors and assigns.

                8.      This Agreement and the rights and obligations of the
parties hereto shall in all respects be governed by, and construed and enforced
in accordance with, the laws of the State of Vermont (without giving effect to
Vermont's choice of law principles).

                9.      This Agreement may be executed in multiple counterparts,
each of which shall constitute an original and together which shall constitute
but one and the same instrument.

                10.     The information set forth on the cover hereof is
incorporated herein.

                  [Remainder of page intentionally left blank]

                                        3


                IN WITNESS WHEREOF, this Agreement has been duly executed and
delivered by each of the parties hereto as of the day and year first above
written.

                                        HEATHCOTE ASSOCIATES, L.P.,
                                        a New York limited partnership

                                        By: Acadia Heathcote, LLC,
                                            its general partner

                                            By: Acadia Realty Limited
                                                Partnership, a Delaware
                                                limited partnership,
                                                its sole member

                                                By: Acadia Realty Trust, a
                                                    Maryland real estate
                                                    investment trust,
                                                    its general partner
Witness:


- ------------------------------                      By
                                                       -------------------------
Print Name:                                            Robert Masters
                                                       Senior Vice President

                                        FLEET NATIONAL BANK, as Administrative
Witness:                                Agent


- ------------------------------          By
                                            ------------------------------------
Print Name:                                 Denise M. Smyth
                                            Vice President

                The undersigned joins in the execution and authorizes the
delivery of this Mortgage Modification Agreement for the purpose of confirming
and reaffirming its acceptance and agreement to the provisions of paragraph 3.16
of the Original Mortgage.

                                        ACADIA REALTY LIMITED PARTNERSHIP

Witness:                                By: Acadia Realty Trust,
                                            its general partner


- ------------------------                    By
                                               --------------------------------
Print Name:                                    Robert Masters
                                               Senior Vice President



STATE OF NEW YORK             )
                              :    ss.:
COUNTY OF NEW YORK            )

                On the 30th day of June in the year 2004, before me, the
undersigned, a notary public in and for said state, personally appeared Robert
Masters, personally known to me or proved to me on the basis of satisfactory
evidence to be the individual(s) whose name(s) is (are) subscribed to the within
instrument and acknowledged to me that he/she/they executed the same in
his/her/their capacity(ies), and that by his/her/their signature(s) on the
instrument, the individual(s), or the person upon behalf of which the
individual(s) acted, executed the instrument.


                                        ----------------------------------------
                                        Notary Public

My Commission Expires:


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STATE OF NEW YORK             )
                              :    ss.:
COUNTY OF NEW YORK            )

                On the 30th day of June in the year 2004, before me, the
undersigned, a notary public in and for said state, personally appeared Denise
M. Smyth, personally known to me or proved to me on the basis of satisfactory
evidence to be the individual(s) whose name(s) is (are) subscribed to the within
instrument and acknowledged to me that he/she/they executed the same in
his/her/their capacity(ies), and that by his/her/their signature(s) on the
instrument, the individual(s), or the person upon behalf of which the
individual(s) acted, executed the instrument.


                                        ----------------------------------------
                                        Notary Public

My Commission Expires:


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                                   SCHEDULE A