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                                                                   EXHIBIT 10.21

                              ASSUMPTION AGREEMENT

      This Assumption Agreement ("AGREEMENT") is made this 21st day of February,
2006, by LASALLE BANK NATIONAL ASSOCIATION, as Trustee for Bear Stearns
Commercial Mortgage Securities, Inc., Commercial Mortgage Securities
Pass-Through Certificates Series 2004 - PWR3 ("LENDER"), STONEWATER DOX FUNDING
LLC, a Delaware limited liability company ("BORROWER"), STONEWATER FUNDING LLC,
a Delaware limited liability company, ("GUARANTOR"), ACI06 CHAMPAIGN IL LLC, a
Delaware limited liability company ("NEW BORROWER"), and GLADSTONE COMMERCIAL
CORPORATION, a Maryland corporation ("NEW GUARANTOR").

                                    RECITALS

A.    Wells Fargo Bank, National Association (the "ORIGINAL LENDER") made a loan
      to Borrower in the original principal amount of Ten Million and no/100ths
      Dollars ($10,000,000.00) ("LOAN"), under the terms and provisions set
      forth in the following loan documents, all of which are dated as of
      November 21, 2003 unless otherwise noted:

      1.    Promissory Note Secured By Mortgage ("NOTE") in the original
            principal amount of the Loan, made by Borrower and payable to
            Lender's predecessor in interest;

      2.    Mortgage and Absolute Assignment of Rents and Leases and Security
            Agreement (and Fixture Filing) ("Security Instrument"), executed by
            Borrower, as Mortgagor, for the benefit of Original Lender, as
            Mortgagee, which secures the Note and other obligations of Borrower
            and which was recorded on November 25, 2003, as Instrument No.
            2003R52081, in the Office of the Recorder of Champaign County,
            Illinois ("OFFICIAL RECORDS"), the Mortgagee's interest under which
            was assigned by instrument recorded on May 4, 2004, as Instrument
            No.2004R12813, in the Official Records. The land, improvements and
            other real property which are subject to the Security Instrument are
            hereinafter referred to as the "PROPERTY" and the equipment,
            machinery and other personal property which are subject to the
            Security Instrument are hereinafter referred to as the "COLLATERAL";

      3.    Limited Guaranty ("GUARANTY") executed by Guarantor and by other
            guarantors, which other guarantors have since been released under
            the terms of a Guarantor Release Agreement dated as of
            (approximately) January 12, 2005;

      4.    Assignment of Management Contracts ("ASSIGNMENT OF MANAGEMENT
            CONTRACTS") given by Borrower to Original Lender;

      5.    Agreement Regarding Required Insurance ("AGREEMENT REGARDING
            REQUIRED INSURANCE") by and between Borrower and Original Lender;

      6.    Cash Management Agreement by and between Borrowers and Original
            Lender ("CASH MANAGEMENT AGREEMENT"); and

      7.    UCC-1 Financing Statements filed with the New York Secretary of
            State and the Secretary of State of the State of Illinois.

            The above documents and any other Loan Documents (as defined in the
            Note and listed in Exhibit B to the Note, and incorporated therein),
            including, in each case, any prior amendments thereto, together with
            this Agreement and the documents executed in connection with this
            Agreement, including without limitation, the Borrower's
            Certification of even date, with all attachments, executed by New
            Borrower ("BORROWER'S CERTIFICATION") that certain Guarantor's
            Financial Certificate of even date, with all attachments, executed

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            by New Guarantor ("GUARANTOR'S FINANCIAL CERTIFICATE"); the
            Assignment of Management Contracts executed by New Borrower of even
            date, with its attached Consent, Subordination and Agreement of
            Manager dated February 15, 2006, executed by the Manager named
            therein (both documents together, the "NEW ASSIGNMENT AND CONSENT")
            and the UCC-1 and UCC-3 Financing Statements of even date ("NEW
            FINANCING STATEMENTS") are hereinafter collectively defined as the
            "LOAN DOCUMENTS"; provided however, that the term Loan Documents
            shall not include the Guaranty, the New Guaranty defined
            hereinafter, nor any other guaranty given in connection with the
            Loan.

B.    Original Lender transferred the Note to Lender and assigned to Lender all
      of its rights under the Loan Documents and the guaranty.

C.    As of February 6, 2006:

      1.    The principal balance outstanding under the Note was Nine Million
            Seven Hundred Forty-Two Thousand One Hundred Sixty-Seven and 02/100s
            Dollars ($9,742,167.02);

      2.    Accrued interest on the Note has been paid through January 31, 2006;

      3.    Accrued but unpaid interest on the Note was Seven Thousand Nine
            Hundred Ninety-Six and 70/100s Dollars ($7996.70);

      4.    The balance in the tax escrow reserve was One Hundred Twenty-Seven
            Thousand One Hundred Eighty-Eight and 78/100s Dollars ($127,188.78);
            and

      5.    The balance in the insurance escrow reserve was Ten Thousand Seven
            Hundred Forty-Nine and 65/100Dollars ($10,749.65).

D.    Borrower has sold and conveyed the Property and the Collateral to New
      Borrower, or is about to sell and convey the Property and the Collateral
      to New Borrower, and both parties desire to obtain from Lender a waiver of
      any right Lender may have under the Loan Documents to accelerate the
      Maturity Date of the Note by virtue of such conveyance.

E.    Subject to the terms and conditions hereof, Lender is willing to waive any
      right of acceleration of the Maturity Date of the Note upon assumption by
      New Borrower of all obligations of Borrower under the Loan Documents.

NOW THEREFORE, FOR VALUABLE CONSIDERATION, including, without limitation, the
mutual covenants and promises contained herein, the parties agree as follows:

      1.    INCORPORATION. The foregoing recitals are incorporated herein by
            this reference.

      2.    ASSUMPTION FEE. As consideration for Lender's execution of this
            Agreement and in addition to any other sums due hereunder, Borrower
            and New Borrower agree to pay Lender or Lender's servicers (all as
            set forth in the escrow instructions to be executed in connection
            with the closing of this assumption) an assumption fee of Ninety
            Seven Thousand Four hundred Twenty-One and 67/100s Dollars
            ($97,421.67), due on execution of this Agreement by Lender.

      3.    CONDITIONS PRECEDENT. The following are conditions precedent to
            Lender's obligations under this Agreement:

            a.    The irrevocable commitment of Chicago Title Insurance Company
                  ("TITLE COMPANY") to issue CLTA 104.8 and CLTA 111.4 (or
                  equivalent) endorsements to Title Company's Title Policy
                  No.1253-000819403-CHA, dated November 25, 2003, in each case
                  in form and substance acceptable to Lender and without
                  deletions or exceptions other than as expressly approved by
                  Lender in writing, insuring Lender that the priority and
                  validity of the Security Instrument has not been and will not
                  be impaired by this Agreement, the conveyance of the Property,
                  or the transaction contemplated hereby;

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            b.    Receipt and approval by Lender of: (i) the executed original
                  of this Agreement; (ii) an executed original of a Memorandum
                  of Assumption Agreement in the form attached hereto as Exhibit
                  A and otherwise in form and substance acceptable to Lender
                  ("MEMORANDUM OF ASSUMPTION AGREEMENT"); and (iii) any other
                  documents and agreements which are required pursuant to this
                  Agreement, in form and content acceptable to Lender;

            c.    Recordation in the Official Records of the Memorandum of
                  Assumption Agreement, together with such other documents and
                  agreements, if any, required pursuant to this Agreement or
                  which Lender has reasonably requested to be recorded or filed
                  in connection with this Agreement;

            d.    New Borrower's delivery to Lender of UCC-1 and UCC-3 Financing
                  Statements in proper form for filing in the appropriate
                  jurisdictions as determined by Lender;

            e.    Execution and delivery to Lender by New Guarantor of a
                  personal Limited Guaranty ("NEW GUARANTY") in favor of Lender
                  and in form and substance acceptable to Lender, pursuant to
                  which New Guarantor irrevocably guarantees payment for certain
                  matters under the Loan as more specifically set forth in the
                  New Guaranty;

            f.    Delivery to Lender of the Borrower's Certification and
                  Guarantor's Financial Certificate, with attachments, including
                  without limitation organizational documents and evidence of
                  good standing of New Borrower and New Guarantor, together with
                  such resolutions or certificates as Lender may reasonably
                  require, in form and content reasonably acceptable to Lender,
                  authorizing the assumption of the Loan and the New Guaranty
                  and executed by the appropriate persons and/or entities on
                  behalf of New Borrower and New Guarantor;

            g.    The representations and warranties contained herein are true
                  and correct in all material respects on the date made and are
                  reconfirmed as true and correct in all material respects on
                  the date of the consummation of the transactions contemplated
                  by this Agreement;

            h.    Receipt by Lender of a copy of New Borrower's (or its
                  Tenant's) casualty insurance policy and comprehensive
                  liability insurance policy with respect to the Property or ,
                  in lieu thereof, certificates issued by the insurance carriers
                  evidencing the coverages afforded by such policies, each in
                  form and amount satisfactory to Lender;

            i.    Receipt by Lender of a copy of the grant deed by which title
                  to the Property will be conveyed to New Borrower, the bill of
                  sale by which the personal property will be transferred, and
                  the purchase and sale agreement documenting the sale of the
                  Property to New Borrower;

            j.    Receipt by Lender of an executed assignment of the purchaser's
                  interest in the purchase and sale agreement for the Property
                  from the purchaser named therein to New Borrower;

            k.    Receipt by Lender of an executed Form W-9 for New Borrower;

            l.    Receipt by Lender of a copy of the assignment and assumption
                  agreement by which the existing property management agreement
                  for the Property has been assigned to and assumed by New
                  Borrower;

            m.    Lender shall have received an opinion of counsel to Lender
                  that the transfer to New Borrower, and the consummation of the
                  transactions referenced herein are in compliance with the
                  provisions of the Internal Revenue Code as the same pertain to
                  real estate mortgage investment conduits;

            n.    Payment of the assumption fee provided for in Section 2 above;
                  and

            o.    Borrower's or New Borrower's reimbursement to Lender of
                  Lender's costs and expenses incurred in connection with this
                  Agreement and the transactions contemplated hereby, including,
                  without limitation, title insurance costs, escrow and
                  recording fees, reasonable attorneys' fees, appraisal,

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                  engineers' and inspection fees and documentation costs and
                  charges, whether such services are furnished by Lender's
                  employees, agents or independent contractors.

      4.    EFFECTIVE DATE. The effective date of this Agreement shall be the
            date the Memorandum of Assumption Agreement is recorded in the
            Official Records ("EFFECTIVE DATE").

      5.    ASSUMPTION. New Borrower hereby assumes and agrees to pay when due
            all sums due or to become due or owing under the Note, the Security
            Instrument and the other Loan Documents and shall hereafter
            faithfully perform all of Borrower's obligations under and be bound
            by all of the provisions of the Loan Documents and assumes all
            liabilities of Borrower under the Loan Documents as if New Borrower
            were an original signatory thereto. The execution of this Agreement
            by New Borrower shall be deemed its execution of the Note, the
            Security Instrument and the other Loan Documents.

      6.    PARTIAL RELEASE OF BORROWER AND GUARANTOR; RELEASE OF LENDER.

            a.    Lender hereby releases (on the Effective Date) Borrower and
                  Guarantor from liability under the Loan Documents other than
                  this Agreement; provided however, that the parties hereby
                  acknowledge and agree that Borrower and Guarantor are
                  expressly not released from and nothing contained herein is
                  intended to limit, impair, terminate or revoke, any of
                  Borrower's and Guarantor's obligations with respect to the
                  matters set forth in Section 8.2 of the Note or Borrower's and
                  Guarantor's liability for breaches of their representations
                  and warranties under the Loan Documents, to the extent the
                  same arise out of or in connection with any act or omission
                  occurring on or before the Effective Date (the "RETAINED
                  OBLIGATIONS"), and that such obligations shall continue in
                  full force and effect in accordance with the terms and
                  provisions thereof and hereof. Borrower's and Guarantor's
                  obligations under the Loan Documents with respect to the
                  Retained Obligations shall not be discharged or reduced by any
                  extension, amendment, renewal or modification to, the Note,
                  the Security Instrument or any other Loan Documents,
                  including, without limitation, changes to the terms of
                  repayment thereof, modifications, extensions or renewals of
                  repayment dates, releases or subordinations of security in
                  whole or in part, changes in the interest rate or advances of
                  additional funds by Lender in its discretion for purposes
                  related to those set forth in the Loan Documents.

            b.    Each of Borrower, Guarantor, New Borrower and New Guarantor
                  hereby fully releases (on the Effective Date) Lender and any
                  servicer(s) of the Loan from any liability of any kind to
                  Borrower arising out of or in connection with the Loan or the
                  Loan Documents prior to the Effective Date other than this
                  Agreement. With respect to the immediately preceding sentence,
                  each of Borrower, Guarantor, New Borrower and New Guarantor
                  after consultation with its respective attorney, hereby
                  expressly waives the benefits of the provisions of applicable
                  law, if any, which provides to the effect that:

                        "A general release does not extend to claims which the
                        creditor does not know or suspect to exist in his favor
                        at the time of executing the release which, if known by
                        him, must have materially affected his settlement with
                        the debtor."

            From time to time without first requiring performance on the part of
            New Borrower, Lender may look to and require performance by Borrower
            of all Retained Obligations. Borrower waives all presentments,
            demands for performance, notices of nonperformance, protests,
            notices of protest and notices of dishonor of all or any part of the
            indebtedness now existing or hereafter arising under the Loan
            Documents

      7.    CONFIRMATION OF GUARANTY; PARTIAL RELEASE OF GUARANTOR. Nothing
            contained herein is intended to limit, impair, terminate or revoke
            Guarantor's obligations under the Guaranty to the extent the same
            arise out of or in connection with any act or omission occurring on
            or before the Effective Date and such obligations shall continue in
            full force and effect in accordance with the terms and provisions of
            the Guaranty; provided, however, Lender hereby releases Guarantor
            from its obligations under the Guaranty to the extent the same arise
            out of or in connection with any act or omission occurring after the
            Effective Date.

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      8.    REPRESENTATIONS AND WARRANTIES.

            a.    Assignment. Borrower and New Borrower each hereby represents
                  and warrants to Lender that Borrower has irrevocably and
                  unconditionally transferred and assigned to New Borrower all
                  of Borrower's right, title and interest in and to:

                              i.    The Property and the Collateral;

                              ii.   The Loan Documents;

                              iii.  All leases related to the Property or the
                                    Collateral;

                              iv.   All rights as named insured under all
                                    casualty and liability insurance policies
                                    (and all endorsements in connection
                                    therewith) relating to the Property or the
                                    Collateral (unless, but only to the extent
                                    that, New Borrower is obtaining its own such
                                    insurance policies);

                              v.    All reciprocal easement agreements,
                                    declarations of conditions, covenants and
                                    restrictions and other matters encumbering
                                    or benefiting the Property, whether or not
                                    recorded in the land records;

                              vi.   All prepaid rents and security deposits, if
                                    any, held by Borrower in connection with
                                    leases of any part of the Property or the
                                    Collateral; and

                              vii.  All funds, if any, deposited in impound
                                    accounts held by or for the benefit of
                                    Lender pursuant to the terms of the Loan
                                    Documents.

            b.    No Consents Required.

                              i.    Borrower hereby further represents and
                                    warrants to Lender that no consent to the
                                    transfer of the Property and the Collateral
                                    to New Borrower is required under any
                                    agreement to which Borrower is a party,
                                    including, without limitation, under any
                                    lease, operating agreement, mortgage or
                                    security instrument (other than the Loan
                                    Documents), or if such consent is required,
                                    that the parties have obtained all such
                                    consents.

                              ii.   New Borrower hereby further represents and
                                    warrants to Lender that no consent to the
                                    transfer of the Property and the Collateral
                                    to New Borrower is required under any
                                    agreement to which New Borrower is a party,
                                    including, without limitation, under any
                                    lease, operating agreement, mortgage or
                                    security instrument (other than the Loan
                                    Documents), or if such consent is required,
                                    that the parties have obtained all such
                                    consents.

            c.    No Defaults.

                              i.    New Borrower hereby represents and warrants
                                    to Lender , to the best of its knowledge,
                                    that no default, event of default, breach or
                                    failure of condition has occurred, or would
                                    exist with notice or the lapse of time or
                                    both, under any of the Loan Documents, as
                                    modified by this Agreement, and all
                                    representations and warranties herein and in
                                    the other Loan Documents are true and
                                    correct.

                              ii    Borrower hereby represents and warrants to
                                    Lender and to New Borrower, to the best of
                                    its knowledge, that no default, event of
                                    default, breach or failure of condition has
                                    occurred, or would exist with notice or the
                                    lapse of time or both, under any of the Loan

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                                    Documents, as modified by this Agreement,
                                    and all representations and warranties
                                    herein and in the other Loan Documents are
                                    true and correct.

                              iii   Lender hereby represents and warrants to New
                                    Borrower, to the best of its knowledge, that
                                    no default, event of default, breach or
                                    failure of condition has occurred, or would
                                    exist with notice or the lapse of time or
                                    both, under any of the Loan Documents, as
                                    modified by this Agreement.

            d.    Loan Documents. New Borrower represents and warrants to Lender
                  that New Borrower has actual knowledge of all terms and
                  conditions of the Loan Documents, and agrees that Lender has
                  no obligation or duty to provide any information to New
                  Borrower regarding the terms and conditions of the Loan
                  Documents. New Borrower further agrees that all
                  representations, agreements and warranties in the Loan
                  Documents regarding Borrower, its status, authority, financial
                  condition and business shall apply to New Borrower as well as
                  to Borrower, as though New Borrower were the borrower
                  originally named in the Loan Documents. New Borrower further
                  understands and acknowledges that, except as expressly
                  provided in a writing executed by Lender, Lender has not
                  waived any right of Lender or obligation of Borrower or New
                  Borrower under the Loan Documents and Lender has not agreed to
                  any modification of any provision of any Loan Document or to
                  any extension of the Loan.

            e.    Financial Statements. New Borrower represents and warrants to
                  Lender that the financial statements of New Borrower and of
                  each member of New Borrower (if New Borrower is a limited
                  liability company) and of each New Guarantor, if any,
                  previously delivered by or on behalf of New Borrower to
                  Lender: (i) are materially complete and correct; (ii) present
                  fairly the financial condition of each of such parties as of
                  the date such financial statements were made; and (iii) have
                  been prepared in accordance with generally accepted accounting
                  principles consistently applied or other accounting standards
                  approved by Lender. New Borrower further represents and
                  warrants to Lender that, since the date of such financial
                  statements, there has been no material adverse change in the
                  financial condition of any of such parties, nor have any
                  assets or properties reflected on such financial statements
                  been sold, transferred, assigned, mortgaged, pledged or
                  encumbered except as previously disclosed in writing by New
                  Borrower to Lender and Lender has acknowledged in writing its
                  receipt and approval of such changes so disclosed.

            f.    Reports. New Borrower represents and warrants to Lender that
                  all reports, documents, instruments and information delivered
                  to Lender by New Borrower in connection with New Borrower's
                  assumption of the Loan: (i) are correct and sufficiently
                  complete to give Lender accurate knowledge of their subject
                  matter; and (ii) do not contain any misrepresentation of a
                  material fact or omission of a material fact which omission
                  makes the provided information misleading.

            g.    New Borrower Location. New Borrower's chief executive office
                  is located at the following address: 1521 Westbranch Drive,
                  Suite 200, McLean, VA 22102. New Borrower is an organization
                  organized solely under the laws of the State of Delaware. All
                  organizational documents of New Borrower delivered to Lender
                  are complete and accurate in every respect. New Borrower's
                  legal name is exactly as shown on page one of this Agreement.
                  New Borrower shall not change New Borrower's name or, as
                  applicable, New Borrower's chief executive office, or the
                  jurisdiction in which New Borrower is organized, without
                  giving Lender at least 30 days' prior written notice.

            h.    No Adverse Change. New Borrower represents and warrants to
                  Lender that since the date of the financial statements for New
                  Borrower and New Guarantor submitted by New Borrower in
                  connection with its application to assume the Loan, there has
                  occurred no adverse change in the financial condition of New
                  Borrower or New Guarantor.

            i.    No Pledge of Equity Interests. New Borrower represents and
                  warrants to Lender that no equity interest in New Borrower or
                  in any entity that, directly or indirectly, owns an equity
                  interest in New Borrower has been pledged, hypothecated or
                  otherwise encumbered as security for any obligation, and that
                  no portion of the capital contributed to New Borrower,
                  directly or indirectly, in connection with New Borrower's
                  acquisition of the Property consists of borrowed funds.

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      9.    MODIFICATION TO CASH MANAGEMENT AGREEMENT. New Borrower and Lender
            hereby agree that the Cash Management Agreement is amended as
            provided in this Section 9:

            a.    Recital C of the Cash Management Agreement is hereby amended
                  by deleting the identifying account number of the Restricted
                  Account, which number appears in the fifth line of Recital C
                  and replacing it with the following number, which shall
                  hereafter be the identifying account number for the Restricted
                  Account.: 4121279590.

            b.    Section 1.1 of the Cash Management Agreement is hereby amended
                  by the deleting the second-to-last sentence thereof and
                  substituting therefor the following:

                        "The Restricted Account and Excess Cash Flow Subaccount
                        shall be assigned the federal tax identification number
                        of Borrower, which number is 91-2198700".

            c.    Section 4.1(a) (ii) of the Cash Management Agreement is hereby
                  amended by deleting the second sentence thereof and
                  substituting therefor the following:

                        "Borrower has established an account at Briggs Bank and
                        Trust Company; account name: ACI06 Champaign IL LLC;
                        Bank's ABA # 051404260
                        ("Borrower's Operations Account")."

      10.   MODIFICATION TO SECURITY INSTRUMENT

            a.    KEY PERSON OR ENTITY. New Borrower, Borrower and Lender hereby
                  agree that Section 7.1(a) (vi) of the Security Instrument is
                  hereby deleted in its entirety.

            b.    "ACTUAL KNOWLEDGE" STANDARD. The parenthetical in the first
                  paragraph in Section 5.1 is replaced by the following:
                  "("actual knowledge" means the knowledge of the Borrower based
                  solely on the Purchase and Sale Agreement dated November 22,
                  2005 between, Gladstone Commercial Limited Partnership and
                  Stonewater UIS Funding LLC, as amended, and as assigned by
                  Gladstone Commercial Limited Partnership to Borrower, and/or
                  the conveyance documents delivered pursuant thereto, and
                  Borrower's good faith due diligence investigation in
                  connection with the acquisition of the Property)"

      11.   MODIFICATION TO NOTE. Paragraph 3.5 of Exhibit A is amended by
            striking the following words, proper names and figures:

                        "Bank Name: LaSalle National Bank
                        ABA Routing No.: 071000505
                        Account Name: Stonewater DOX Funding LLC
                        Reference: Amdocs
                        Advise: John Reinsma, Ext. 4-0282"

                        and replacing them with:

                        "Bank Name: Briggs Bank and Trust Company
                        ABA Routing No.: 051404260
                        Account Name: ACI06 Champaign IL LLC
                        Reference: Amdocs
                        Advise: Matt Tucker "

      12.   TRANSFERS OF GLADSTONE COMMERCIAL CORPORATION. Lender hereby
            acknowledges and agrees that, notwithstanding anything set forth
            herein or in the Loan Documents, the trading or issuance of shares
            or other securities of Gladstone Commercial Corporation, a Maryland
            corporation, in the public or private markets shall not constitute a
            Transfer under Section 6.15 of the Security Instrument.

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      13.   WAIVER OF ACCELERATION. Lender hereby agrees that it shall not
            exercise its right to cause all sums secured by the Security
            Instrument to become immediately due and payable because of the
            conveyance of the Property and the Collateral from Borrower to New
            Borrower; provided, however, Lender reserves its right under the
            terms of the Security Instrument or any other Loan Document to
            accelerate all principal and interest in the event of any subsequent
            sale, transfer, encumbrance or other conveyance of the Property, the
            Collateral or any interest in New Borrower, except as permitted by
            the Loan Documents.

      14.   HAZARDOUS MATERIALS. Without in any way limiting any other provision
            of this Agreement, New Borrower and Borrower expressly reaffirm as
            of the date hereof, and New Borrower reaffirms continuing hereafter:
            (a) each and every representation and warranty in the Loan Documents
            respecting "HAZARDOUS MATERIALS"; and (b) each and every covenant
            and indemnity in the Loan Documents respecting "HAZARDOUS
            MATERIALS".

      15.   MULTIPLE PARTIES. If more than one person or entity has signed this
            Agreement as New Borrower or Borrower, then all references in this
            Agreement to New Borrower or Borrower shall mean each and all of the
            persons so signing, as applicable. The liability of all persons and
            entities signing shall be joint and several with all others
            similarly liable.

      16.   CONFIRMATION OF SECURITY INTEREST. Nothing contained herein shall
            affect or be construed to affect any lien, charge or encumbrance
            created by any Loan Document or the priority of that lien, charge or
            encumbrance. All assignments and transfers by Borrower to New
            Borrower are subject to any security interest(s) held by Lender.

      17.   NOTICES. All notices to be given to New Borrower pursuant to the
            Loan Documents shall be addressed as follows:

                               ACI06 Champaign IL LLC
                               c/o Gladstone Commercial Corporation
                               1521 Westbranch Drive - Suite 200
                               McLean, VA 22102
                               Attention:   Danielle Seidman
                               Facsimile:   (703) 287-5801

                               With a copy to:

                               Dickstein Shapiro Morin & Oshinsky LLP
                               2101 L Street, NW
                               Washington, DC  20037
                               Attn:  James D. Kelly, Esq.
                               Facsimile:  (202) 887-0689

      18.   INTEGRATION; INTERPRETATION. The Loan Documents, including this
            Agreement, contain or expressly incorporate by reference the entire
            agreement of the parties with respect to the matters contemplated
            herein and supersede all prior negotiations. The Loan Documents
            shall not be modified except by written instrument executed by
            Lender and New Borrower. Any reference in any of the Loan Documents
            to the Property or the Collateral shall include all or any parts of
            the Property or the Collateral.

      19.   SUCCESSORS AND ASSIGNS. This Agreement is binding upon and shall
            inure to the benefit of the heirs, successors and assigns of the
            parties but subject to all prohibitions of transfers contained in
            any Loan Document.

      20.   ATTORNEYS' FEES; ENFORCEMENT. If any attorney is engaged by Lender
            to enforce, construe or defend any provision of this Agreement, or
            as a consequence of any default under or breach of this Agreement,
            with or

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            without the filing of any legal action or proceeding, New
            Borrower shall pay to Lender, upon demand, the amount of all
            attorneys' fees and costs reasonably incurred by Lender in
            connection therewith, together with interest thereon from the date
            of such demand at the rate of interest applicable to the principal
            balance of the Note as specified therein.

      21.   ONE-TIME RIGHT OF TRANSFER OF PROPERTY. The parties acknowledge that
            Section 4 of Exhibit A to Promissory Note attached to and forming a
            part of the Note provides that Lender shall, one (1) time only,
            consent to the voluntary sale or exchange of all of the Property,
            all subject, however, to the terms and conditions set forth therein.
            The parties agree that this Agreement and the actions to be taken as
            contemplated herein shall constitute such one consent and that
            hereafter, Lender shall not be required to consent to any further
            such sale or exchange.

      22.   MISCELLANEOUS. This Agreement shall be governed and interpreted in
            accordance with the laws of the jurisdiction(s) specified in the
            other Loan Documents as governing the other Loan Documents. In any
            action brought or arising out of this Agreement, Borrower and New
            Borrower, and general partners, members and joint venturers of them,
            hereby consent to the jurisdiction of any state or federal court
            having proper venue as specified in the other Loan Documents and
            also consent to the service of process by any means authorized by
            the law of such jurisdiction(s). Except as expressly provided
            otherwise herein, all terms used herein shall have the meaning given
            to them in the other Loan Documents. Time is of the essence of each
            term of the Loan Documents, including this Agreement. If any
            provision of this Agreement or any of the other Loan Documents shall
            be determined by a court of competent jurisdiction to be invalid,
            illegal or unenforceable, that portion shall be deemed severed
            therefrom and the remaining parts shall remain in full force as
            though the invalid, illegal, or unenforceable portion had not been a
            part thereof.

      23.   COUNTERPARTS. This Agreement may be executed in any number of
            counterparts, each of which when executed and delivered will be
            deemed an original and all of which taken together will be deemed to
            be one and the same instrument.

            [The remainder of this page is intentionally left blank.]

                                       9
<PAGE>

IN WITNESS WHEREOF, Borrower, Guarantor, New Borrower, New Guarantor and Lender
have caused this Agreement to be duly executed as of the date first above
written.

LENDER:

LASALLE BANK NATIONAL ASSOCIATION, as Trustee for Bear Stearns Commercial
Mortgage Securities, Inc., Commercial Mortgage Securities Pass-Through
Certificates Series 2004 - PWR3

By:   WELLS FARGO BANK, NATIONAL ASSOCIATION, as Master Servicer under the
      Pooling and Servicing Agreement dated March 1, 2004, by and between Bear
      Stearns Commercial Mortgage Securities, Inc., Prudential Asset Resources,
      Inc., Wells Fargo Bank, National Association, Arcap Servicing, Inc.,
      LaSalle Bank National Association, ABN AMRO Bank N.V. and The Prudential
      Insurance Company of America

      By:    _______________________________
      Name:  _______________________________
      Title: _______________________________

[Signatures continued on next page]

                                       10
<PAGE>

BORROWER

STONEWATER DOX FUNDING LLC,
a Delaware limited liability company

By:     __________________________________
Name:   Constantine Dakolias
Title:  Vice President

GUARANTOR

STONEWATER FUNDING LLC,
a Delaware limited liability company

By:     __________________________________
Name:   Constantine Dakolias
Title:  Vice President

[Signatures continued on next page]

                                       11
<PAGE>

NEW BORROWER

ACI06 CHAMPAIGN IL LLC,
a Delaware limited liability company

By:     ____________________________
Name:   ____________________________
Title:  ____________________________

NEW GUARANTOR

GLADSTONE COMMERCIAL CORPORATION,
a Maryland corporation

By:            __________________________
Name:          __________________________
Title:         __________________________

                                       12
<PAGE>

Recording Requested by                                                 Exhibit A
and when recorded return to:

PEPLER MASTROMONACO LLP
100 First Street, 25th Floor
San Francisco, California  94105
Attention:  Barrie Cowan, Esq.

Loan No.: 31-0901388

                       MEMORANDUM OF ASSUMPTION AGREEMENT

STONEWATER DOX FUNDING, LLC, a Delaware limited liability company ("BORROWER"),
with a mailing address at c/o Stonewater Partners, 237 Mamaroneck Avenue, Suite
406, White Plains, NY 10605, STONEWATER FUNDING LLC, a Delaware limited
liability company ("GUARANTOR"), with a mailing address at c/o Stonewater
Partners, 237 Mamaroneck Avenue, Suite 406, White Plains, NY 10605, ACI06
CHAMPAIGN IL LLC, a Delaware limited liability company, ("NEW BORROWER"), with a
mailing address at 1521 Westbranch Drive, Suite 200, McLean, VA 22102, GLADSTONE
COMMERCIAL CORPORATION ("NEW GUARANTOR"), with a mailing address at 1521
Westbranch Drive, Suite 200, McLean, VA 22102, and LASALLE BANK NATIONAL
ASSOCIATION, as Trustee for Bear Stearns Commercial Mortgage Securities, Inc.,
Commercial Mortgage Securities Pass-Through Certificates Series 2004 - PWR3
("LENDER"), with a mailing address at c/o Wells Fargo Bank, N.A., Commercial
Mortgage Servicing, 1320 Willow Pass Road, Suite 205, Concord, California 94520,
are parties to that certain ASSUMPTION AGREEMENT dated of even date herewith
("ASSUMPTION AGREEMENT"). The undersigned parties agree that all obligations
under that certain Promissory Note Secured by Mortgage ("NOTE") dated November
21, 2003, in the original principal amount of Ten Million and no/100ths Dollars
($10,000,000.00), secured by that certain Mortgage and Absolute Assignment of
Rents and Leases and Security Agreement and Fixture Filing ("SECURITY
INSTRUMENT") recorded November 25, 2003 as Instrument No.2003R52081, in the
office of the Recorder of Champaign County, Illinois ("OFFICIAL RECORDS") the
mortgagee's interest under which was assigned by instrument recorded on May 4,
2004, as Instrument No. 2004R12813, in the Official Records, and all other Loan
Documents (as defined in the Assumption Agreement), have been assumed by New
Borrower upon the terms and conditions set forth in the Assumption Agreement.
The Assumption Agreement is by this reference incorporated herein and made a
part hereof. This Memorandum of Assumption Agreement may be executed in any
number of counterparts, each of which when executed and delivered will be deemed
an original and all of which taken together will be deemed to be one and the
same instrument.

Dated:

February __, 2006

<PAGE>

LENDER:

LASALLE BANK NATIONAL ASSOCIATION, as Trustee for Bear Stearns Commercial
Mortgage Securities, Inc., Commercial Mortgage Securities Pass-Through
Certificates Series 2004 - PWR3

By:   WELLS FARGO BANK, NATIONAL ASSOCIATION, as Master Servicer under the
      Pooling and Servicing Agreement dated March 1, 2004, by and between Bear
      Stearns Commercial Mortgage Securities, Inc., Prudential Asset Resources,
      Inc., Wells Fargo Bank, National Association, Arcap Servicing, Inc.,
      LaSalle Bank National Association, ABN AMRO Bank N.V. and The Prudential
      Insurance Company of America

      By:    __________________________________
      Name:  __________________________________
      Title: __________________________________

<PAGE>

BORROWER

STONEWATER DOX FUNDING LLC,
a Delaware limited liability company

By:    _____________________________________
Name:  Constantine Dakolias
Title: Vice President

GUARANTOR

STONEWATER FUNDING LLC,
a Delaware limited liability company

By:     ___________________________________
Name:   Constantine Dakolias
Title:  Vice President

[Signatures continued on next page]

<PAGE>

NEW BORROWER

ACI06 CHAMPAIGN IL LLC,
a Delaware limited liability company

By:     __________________________________
Name:   __________________________________
Title:  __________________________________

NEW GUARANTOR

GLADSTONE COMMERCIAL CORPORATION,
a Maryland corporation

By:     _________________________________
Name:   _________________________________
Title:  _________________________________

                                       16
<PAGE>

STATE OF VIRGINIA                 )
                                  ) ss
COUNTY OF FAIRFAX                 )

            On this the _____ day of January, 2006, before me, the undersigned
Notary Public, personally appeared ___________________________, proved to me on
the basis of satisfactory evidence to be the person whose name is subscribed to
the within instrument and acknowledged to me that he/she executed the same in
his/her authorized capacity, and that by his/her signature on the instrument the
person or the entity upon behalf of which the person acted, executed the
instrument.

            IN WITNESS WHEREOF, I hereunto set my hand and official seal.

Notary Public
My Commission Expires:

------------------------------------------

                                       17
<PAGE>

STATE OF NEW YORK               )
                                )  ss
COUNTY OF WESTCHESTER           )

            On this the _____ day of January, 2006, before me, the undersigned
Notary Public, personally appeared ___________________________, proved to me on
the basis of satisfactory evidence to be the person whose name is subscribed to
the within instrument and acknowledged to me that he/she executed the same in
his/her authorized capacity, and that by his/her signature on the instrument the
person or the entity upon behalf of which the person acted, executed the
instrument.

            IN WITNESS WHEREOF, I hereunto set my hand and official seal.

Notary Public
My Commission Expires:

-------------------------------------------

                                       18
<PAGE>

STATE OF NEW YORK                    )
                                     )  ss
COUNTY OF WESTCHESTER                )

            On this the _____ day of January, 2006, before me, the undersigned
Notary Public, personally appeared ___________________________, proved to me on
the basis of satisfactory evidence to be the person whose name is subscribed to
the within instrument and acknowledged to me that he/she executed the same in
his/her authorized capacity, and that by his/her signature on the instrument the
person or the entity upon behalf of which the person acted, executed the
instrument.

            IN WITNESS WHEREOF, I hereunto set my hand and official seal.

Notary Public
My Commission Expires:

------------------------------------------

                                       19
<PAGE>

STATE OF CALIFORNIA             )
                                )  ss
COUNTY OF CONTRA COSTA          )

            On this the _____ day of January, 2006, before me, the undersigned
Notary Public, personally appeared ___________________________, proved to me on
the basis of satisfactory evidence to be the person whose name is subscribed to
the within instrument and acknowledged to me that she executed the same in her
authorized capacity, and that by her signature on the instrument the person or
the entity upon behalf of which the person acted, executed the instrument.

            IN WITNESS WHEREOF, I hereunto set my hand and official seal.

Notary Public
My Commission Expires:

-------------------------------------------

                                       20
<PAGE>

                                       21