<PAGE>   1
                                                                    EXHIBIT 4.23

             SECOND AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT

                  for $1,000,000,000 Revolving Credit Facility

                            dated as of May 29, 1998

                                      among

                       EOP OPERATING LIMITED PARTNERSHIP,

                            THE BANKS LISTED HEREIN,

                               NATIONSBANK, N.A.,
                            as Administrative Agent,


                       BANK OF AMERICA NATIONAL TRUST AND
                               SAVINGS ASSOCIATION
                             as Documentation Agent,


                          J.P. MORGAN SECURITIES INC.,
                              as Syndication Agent,

                            THE BANK OF NOVA SCOTIA,
                            THE CHASE MANHATTAN BANK,
                         COMMERZBANK AKTIENGESELLSCHAFT,
                 DRESDNER BANK AG, NEW YORK AND CAYMAN BRANCHES,
                         PNC BANK, NATIONAL ASSOCIATION,
                                       and
                   UNION BANK OF SWITZERLAND, NEW YORK BRANCH,
                               as Managing Agents

                                       AND

                        CREDIT LYONNAIS, NEW YORK BRANCH,
                              FLEET NATIONAL BANK,
                                       and
                         U.S. BANK NATIONAL ASSOCIATION,
                                  as Co-Agents.




<PAGE>   2

                                TABLE OF CONTENTS










<TABLE>

<S>                                                                                      <C>
ARTICLE I
        DEFINITIONS.....................................................................   1

                        SECTION 1.1.  Definitions ......................................   1
                        SECTION 1.2.  Accounting Terms and Determinations ..............  23
                        SECTION 1.3.  Types of Borrowings ..............................  24
                        SECTION 1.4.  Interrelationship with the Existing Credit
                                      Agreement ........................................  24

ARTICLE II THE CREDITS .................................................................  24
                        SECTION 2.1.  Commitments to Lend ..............................  24
                        SECTION 2.2.  Notice of Borrowing ..............................  25
                        SECTION 2.3.  Swingline Loan Subfacility .......................  25
                            (a)Swingline Commitment ....................................  25
                            (b)Swingline Borrowings ....................................  25
                            (c)Interest Rate ...........................................  27
                        SECTION 2.4. Money Market Borrowings ...........................  27
                            (a)The Money Market Option .................................  27
                            (b)Money Market Quote Request ..............................  27
                            (c)Invitation for Money Market Quotes ......................  28
                            (d)Submission and Contents of Money Market
                               Quotes ..................................................  28
                            (e)Notice to Borrower ......................................  29
                            (f)Acceptance and Notice by Borrower .......................  29
                            (g)Allocation by Agent .....................................  30
                        SECTION 2.5. Notice to Banks; Funding of Loans .................  30
                        SECTION 2.6. Notes .............................................  31
                        SECTION 2.7. Method of Electing Interest Rates .................  32
                        SECTION 2.8. Interest Rates ....................................  33
                        SECTION 2.9. Fees ..............................................  34
                            (a)Facility Fee ............................................  34
                            (b)Agency Fees .............................................  34
                            (c)Fees Non-Refundable .....................................  34
                        SECTION 2.10.  Maturity Date ...................................  35
                        SECTION 2.11.  Optional Prepayments ............................  35
                        SECTION 2.12.  General Provisions as to Payments ...............  36
                        SECTION 2.13.  Funding Losses ..................................  37
                        SECTION 2.14.  Computation of Interest and Fees ................  37
                        SECTION 2.15.  Use of Proceeds .................................  37

ARTICLE III CONDITIONS .................................................................  37
                        SECTION 3.1.  Closing ..........................................  37
                        SECTION 3.2.  Borrowings .......................................  39

ARTICLE IV REPRESENTATIONS AND WARRANTIES ..............................................  39
                        SECTION 4.1.  Existence and Power ..............................  40
                        SECTION 4.2.  Power and Authority ..............................  40
                        SECTION 4.3.  No Violation .....................................  40
                        SECTION 4.4.  Financial Information ............................  41
                        SECTION 4.5.  Litigation .......................................  41
                        SECTION 4.6.  Compliance with ERISA ............................  42
                        SECTION 4.7.  Environmental ....................................  42
                        SECTION 4.8.  Taxes ............................................  42
                        SECTION 4.9.  Full Disclosure ..................................  43
                        SECTION 4.10.  Solvency ........................................  43
                        SECTION 4.11.  Use of Proceeds .................................  43
</TABLE>



<PAGE>   3

<TABLE>

<S>                                                                                     <C>
                        SECTION 4.12.  Governmental Approvals ..........................  43
                        SECTION 4.13.  Investment Company Act; Public Utility
                                       Holding Company Act .............................  43
                        SECTION 4.14.  Principal Offices ...............................  43
                        SECTION 4.15.  REIT Status .....................................  43
                        SECTION 4.16.  Patents, Trademarks, etc. .......................  43
                        SECTION 4.17.  Judgments .......................................  43
                        SECTION 4.18.  No Default ......................................  44
                        SECTION 4.19.  Licenses, etc. ..................................  44
                        SECTION 4.20.  Compliance With Law .............................  44
                        SECTION 4.21.  No Burdensome Restrictions ......................  44
                        SECTION 4.22.  Brokers' Fees ...................................  44
                        SECTION 4.23.  Labor Matters ...................................  44
                        SECTION 4.24.  Insurance .......................................  44
                        SECTION 4.25.  Organizational Documents ........................  45
                        SECTION 4.26.  Qualifying Unencumbered Properties ..............  45

                        SECTION 4.27.  "Year 2000" Compliance...........................  45

ARTICLE V AFFIRMATIVE AND NEGATIVE COVENANTS ...........................................  45
                        SECTION 5.1.  Information ......................................  45
                        SECTION 5.2.  Payment of Obligations ...........................  48
                        SECTION 5.3.  Maintenance of Property; Insurance; Leases .......  48
                        SECTION 5.4.  Maintenance of Existence .........................  48
                        SECTION 5.5.  Compliance with Laws .............................  48
                        SECTION 5.6.  Inspection of Property, Books and Records ........  49
                        SECTION 5.7.  Existence ........................................  49
                        SECTION 5.8.  Financial Covenants ..............................  49
                            (a)Total Liabilities to Total Asset Value ..................  49
                            (b)EBITDA to Interest Expense Ratio ........................  49
                            (c)[Intentionally Omitted.] ................................  49
                            (d)Cash Flow to Fixed Charges Ratio ........................  49
                            (e)Secured Debt to Total Asset Value .......................  49
                            (f)Unencumbered Pool .......................................  50
                            (g)Unencumbered Net Operating Income to Unsecured
                               Debt Service ............................................  50
                            (h)Minimum Tangible Net Worth ..............................  50
                            (i)Dividends ...............................................  50
                            (j)Permitted Holdings ......................................  50
                            (k)No Liens ................................................  50
                            (l)Calculation .............................................  50
                        SECTION 5.9.  Restriction on Fundamental Changes ...............  50
                        SECTION 5.10.  Changes in Business .............................  51
                        SECTION 5.11.  EOPT Status .....................................  51
                            (a)Status ..................................................  51
                            (b)Indebtedness ............................................  51
                            (c)Restriction on Fundamental Changes ......................  52
                            (d)Environmental Liabilities ...............................  52
                            (e)Disposal of Partnership Interests .......................  52
                        SECTION 5.12.  Other Indebtedness ..............................  53
                        SECTION 5.13.  Forward Equity Contracts. .......................  53

ARTICLE VI DEFAULTS ....................................................................  53
                        SECTION 6.1.  Events of Default ................................  53
                        SECTION 6.2.  Rights and Remedies ..............................  56
</TABLE>



<PAGE>   4

<TABLE>

<S>                                                                                     <C>
                        SECTION 6.3.  Notice of Default ................................  56
                        SECTION 6.4.  Distribution of Proceeds after Default ...........  56

ARTICLE VII THE AGENTS .................................................................  57
                        SECTION 7.1. Appointment and Authorization .....................  57
                        SECTION 7.2. Agency and Affiliates .............................  57
                        SECTION 7.3. Action by Administrative Agent and
                                     Documentation Agent ...............................  57
                        SECTION 7.4. Consultation with Experts .........................  57
                        SECTION 7.5. Liability of Administrative Agent and
                                     Documentation Agent ...............................  58
                        SECTION 7.6. Indemnification ...................................  58
                        SECTION 7.7. Credit Decision ...................................  58
                        SECTION 7.8. Successor Administrative Agent, Documentation
                                     Agent or Syndication Agent ........................  59
                        SECTION 7.9. Consents and Approvals ............................  60

ARTICLE VIII CHANGE IN CIRCUMSTANCES ...................................................  60
                        SECTION 8.1.  Basis for Determining Interest Rate Inadequate
                                      or Unfair ........................................  60
                        SECTION 8.2.  Illegality .......................................  60
                        SECTION 8.3.  Increased Cost and Reduced Return ................  61
                        SECTION 8.4.  Taxes ............................................  63
                        SECTION 8.5.  Base Rate Loans Substituted for Affected
                                      Euro-Dollar Loans ................................  64

ARTICLE IX MISCELLANEOUS ...............................................................  65
                        SECTION 9.1.  Notices ..........................................  65
                        SECTION 9.2.  No Waivers .......................................  65
                        SECTION 9.3.  Expenses; Indemnification ........................  66
                        SECTION 9.4.  Sharing of Set-Offs ..............................  67
                        SECTION 9.5.  Amendments and Waivers ...........................  68
                        SECTION 9.6.  Successors and Assigns ...........................  68
                        SECTION 9.7.  Collateral .......................................  71
                        SECTION 9.8.  Governing Law; Submission to Jurisdiction ........  71
                        SECTION 9.9.  Counterparts; Integration;. Effectiveness ........  72
                        SECTION 9.10.  WAIVER OF JURY TRIAL ............................  72
                        SECTION 9.11.  Survival ........................................  72
                        SECTION 9.12.  Domicile of Loans ...............................  72
                        SECTION 9.13.  Limitation of Liability .........................  72
                        SECTION 9.14.  Recourse Obligation .............................  73
                        SECTION 9.15.  Confidentiality .................................  73
                        SECTION 9.16.  Bank's Failure to Fund ..........................  73
                        SECTION 9.17.  Banks' ERISA Covenant ...........................  78
                        SECTION 9.18.  Managing Agents and Co-Agents ...................  78
                        SECTION 9.19.  No Bankruptcy Proceedings .......................  78
</TABLE>


SCHEDULE 1.1
SCHEDULE 4.4 (b)
SCHEDULE 4.6
SCHEDULE 5.11(c)(1)
SCHEDULE 5.11(c)(2)



<PAGE>   5

             SECOND AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT


    THIS SECOND AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT (this
"Agreement") dated as of May 29, 1998 among EOP OPERATING LIMITED PARTNERSHIP
(the "Borrower"), the BANKS listed on the signature pages hereof, NATIONSBANK,
N.A., as Administrative Agent, BANK OF AMERICA NATIONAL TRUST AND SAVINGS
ASSOCIATION, as Documentation Agent, J.P. MORGAN SECURITIES INC., as Syndication
Agent, THE BANK OF NOVA SCOTIA, THE CHASE MANHATTAN BANK, COMMERZBANK
AKTIENGESELLSCHAFT, DRESDNER BANK AG, NEW YORK AND CAYMAN BRANCHES, PNC BANK,
NATIONAL ASSOCIATION, and UNION BANK OF SWITZERLAND, NEW YORK BRANCH, as
Managing Agents, CREDIT LYONNAIS, NEW YORK BRANCH, FLEET NATIONAL BANK, and U.S.
BANK NATIONAL ASSOCIATION, as Co-Agents

                               W I T N E S S E T H

    WHEREAS, the Borrower has executed and delivered to the Agents, the Managing
Agents, the Co-Agents and certain of the Banks that certain Amended and Restated
Revolving Credit Agreement dated as of November 20, 1997, by and among the
Borrower, certain of the Banks, the Managing Agents, the Co-Agents and the
Agents (the "Existing Credit Agreement");

    WHEREAS, the Borrower, the Agents, the Managing Agents, the Co-Agents and
the Banks party to the Existing Credit Agreement desire to amend and restate the
Existing Credit Agreement in its entirety to add additional entities as Banks
and to set forth the terms and conditions under which the Banks may hereafter
extend loans to the Borrower; and

    WHEREAS, it is the intent of the Borrower, the Agents, the Managing Agents,
the Co-Agents and the Banks that this Agreement replace in its entirety the
Existing Credit Agreement and that, from and after the Closing Date (as defined
below), the Existing Credit Agreement shall be of no force and effect, except to
evidence the terms and conditions under which the Borrower heretofore incurred
obligations and liabilities to the Banks, the Agents, the Managing Agents and
the Co-Agents, as evidenced by the Existing Credit Agreement and the Banks', the
Agents', the Managing Agents's and the Co-Agents' books and records;

    NOW, THEREFORE, in consideration of the foregoing and the mutual agreements
herein contained, the parties hereto agree as follows:


                                    ARTICLE I

                                   DEFINITIONS

    SECTION 1.1. Definitions. The following terms, as used herein, have the
following meanings:

    "Absolute Rate Auction" means a solicitation of Money Market Quotes setting
forth Money Market Absolute Rates pursuant to Section 2.4.

    "Adjusted Interbank Offered Rate" as applicable to any Interest Period means
a rate per annum equal to the quotient obtained (rounded upward, if necessary,
to the next higher 1/100 of 1%) by dividing (i) the Interbank Offered Rate
applicable during such Interest Period by (ii) 1.00 minus the Euro-Dollar
Reserve Percentage.




                                       1
<PAGE>   6

    "Administrative Agent" shall mean NationsBank, N.A. in its capacity as
Administrative Agent hereunder, and its permitted successors in such capacity in
accordance with the terms of this Agreement.

    "Administrative Questionnaire" means with respect to each Bank, an
administrative questionnaire in the form prepared by the Administrative Agent
and submitted to the Administrative Agent (with a copy to the Borrower and the
Documentation Agent) duly completed by such Bank.

    "Agents" shall mean the Administrative Agent, the Documentation Agent and
the Syndication Agent, collectively.

    "Agreement" shall mean this Second Amended and Restated Revolving Credit
Agreement as the same may from time to time hereafter be modified, supplemented
or amended.

    "Applicable Fee Percentage" means the respective percentages per annum
determined, at any time, based on the range into which Borrower's Credit Rating
then falls, in accordance with the table set forth below. Any change in
Borrower's Credit Rating causing it to move to a different range on the table
shall effect an immediate change in the Applicable Fee Percentage. In the event
that Borrower receives only two (2) Credit Ratings, and such Credit Ratings are
not equivalent, the Applicable Fee Percentage shall be determined by the lower
of such two (2) Credit Ratings. In the event that Borrower receives more than
two (2) Credit Ratings, and such Credit Ratings are not all equivalent, the
Applicable Fee Percentage shall be determined by the higher of the ratings from
S&P and Moody's, provided that the rating from one of the other Rating Agencies
shall be at least equivalent to such higher rating; provided, further, that if
the rating from one of the other Rating Agencies is not at least equivalent to
the higher of the ratings from S&P and Moody's, then the Applicable Fee
Percentage shall be determined by the second (2nd) highest Credit Rating. In the
event that only one of the Rating Agencies shall have set Borrower's Credit
Rating, then the Applicable Fee Percentage shall be based on such rating only.

<TABLE>
<CAPTION>

         Range of
         Borrower's
         Credit Rating                         Applicable
         (S&P/Moody's                          Fee Percentage
         Ratings)                              (% per annum)
         -------------                         --------------

<S>                                                    <C>
   Non-Investment Grade                              0.20

         BBB-/Baa3                                   0.20

         BBB/Baa2                                    0.20

         BBB+/Baa1                                   0.20

         A-/A3 or better                             0.15
</TABLE>

    "Applicable Interest Rate" means (i) with respect to any Fixed Rate
Indebtedness, the fixed interest rate applicable to such Fixed Rate Indebtedness
at the time in question, and (ii) with respect to any Floating Rate
Indebtedness, either (x) the rate at which the interest rate applicable to such
Floating Rate Indebtedness is actually capped (or fixed pursuant to an interest




                                       2
<PAGE>   7

rate hedging device), at the time of calculation, if Borrower has entered into
an interest rate cap agreement or other interest rate hedging device with
respect thereto or (y) if Borrower has not entered into an interest rate cap
agreement or other interest rate hedging device with respect to such Floating
Rate Indebtedness, the greater of (A) the rate at which the interest rate
applicable to such Floating Rate Indebtedness could be fixed for the remaining
term of such Floating Rate Indebtedness, at the time of calculation, by
Borrower's entering into any unsecured interest rate hedging device either not
requiring an upfront payment or if requiring an upfront payment, such upfront
payment shall be amortized over the term of such device and included in the
calculation of the interest rate (or, if such rate is incapable of being fixed
by entering into an unsecured interest rate hedging device at the time of
calculation, a fixed rate equivalent reasonably determined by Administrative
Agent) or (B) the floating rate applicable to such Floating Rate Indebtedness at
the time in question.

    "Applicable Lending Office" means with respect to any Bank, (i) in the case
of its Base Rate Loans and Swingline Loans, its Domestic Lending Office, (ii) in
the case of its Euro-Dollar Loans, its Euro-Dollar Lending Office, and (iii) in
the case of its Money Market Loans, its Money Market Lending Office.

    "Applicable Margin" means with respect to each Loan, the respective
percentages per annum determined, at any time, based on the range into which
Borrower's Credit Rating then falls, in accordance with the table set forth
below. Any change in Borrower's Credit Rating causing it to move to a different
range on the table shall effect an immediate change in the Applicable Margin. In
the event that Borrower receives only two (2) Credit Ratings, and such Credit
Ratings are not equivalent, the Applicable Margin shall be determined by the
lower of such two (2) Credit Ratings. In the event that Borrower receives more
than two (2) Credit Ratings, and such Credit Ratings are not all equivalent, the
Applicable Margin shall be determined by the higher of the ratings from S&P and
Moody's, provided that the rating from one of the other Rating Agencies shall be
at least equivalent to such higher rating; provided, further, that if the rating
from one of the other Rating Agencies is not at least equivalent to the higher
of the ratings from S&P and Moody's, then the Applicable Margin shall be
determined by the second (2nd) highest Credit Rating. In the event that only one
of the Rating Agencies shall have set Borrower's Credit Rating, then the
Applicable Margin shall be based on such rating only.

<TABLE>
<CAPTION>

Range of                                    Applicable
Borrower's                                  Margin for                          Applicable
Credit Rating                               Base Rate                           Margin for Euro
(S&P/Moody's                                Loans                               Dollar Loans
Ratings)                                    (% per annum)                       (% per annum)
---------------                             -------------                       -------------

<S>                                         <C>                                 <C>
Non-Invest-
ment Grade                                  0.0                                    1.175

BBB-/Baa3                                   0.0                                    0.80

BBB/Baa2                                    0.0                                    0.70

BBB+/Baa1                                   0.0                                    0.60
A-/A3 or better                             0.0                                    0.55
</TABLE>


    "Assignee" has the meaning set forth in Section 9.6(c).



                                       3
<PAGE>   8

    "Balance Sheet Indebtedness" means with respect to any Person and assuming
such Person is required to prepare financial statements in accordance with GAAP,
without duplication, the Indebtedness of such Person which would be required to
be included on the liabilities side of the balance sheet of such Person in
accordance with GAAP. Notwithstanding the foregoing, Balance Sheet Indebtedness
shall include current liabilities and all guarantees of Indebtedness of any
Person.

    "Balloon Payments" shall mean with respect to any loan constituting Balance
Sheet Indebtedness, any required principal payment of such loan which is either
(i) payable at the maturity of such Indebtedness or (ii) in an amount which
exceeds fifteen percent (15%) of the original principal amount of such loan;
provided, however, that the final payment of a fully amortizing loan shall not
constitute a Balloon Payment.

    "Bank" means each entity (other than Borrower) listed on the signature pages
hereof, each Assignee which becomes a Bank pursuant to Section 9.6(c), and their
respective successors and each Designated Lender; provided, however, that the
term "Bank" shall exclude each Designated Lender when used in reference to a
Committed Loan, the Commitments or terms relating to the Committed Loans and the
Commitments and shall further exclude each Designated Lender for all other
purposes hereunder except that any Designated Lender which funds a Money Market
Loan shall, subject to Section 9.6(d), have the rights (including the rights
given to a Bank contained in Section 9.3 and otherwise in Article 9) and
obligations of a Bank associated with holding such Money Market Loan. For
purposes of this Agreement, J.P. Morgan Securities, Inc. shall not constitute a
"Bank."

    "Bankruptcy Code" shall mean Title 11 of the United States Code, entitled
"Bankruptcy", as amended from time to time, and any successor statute or
statutes.

    "Base Rate" means, for any day, a rate per annum equal to the higher of (i)
the Prime Rate for such day and (ii) the sum of 0.5% plus the Federal Funds Rate
for such day. Each change in the Base Rate shall become effective automatically
as of the opening of business on the date of such change in the Base Rate,
without prior written notice to Borrower or Banks.

    "Base Rate Loan" means a Committed Loan to be made by a Bank as a Base Rate
Loan in accordance with the provisions of this Agreement.

    "Benefit Arrangement" means at any time an employee benefit plan within the
meaning of Section 3(3) of ERISA which is not a Plan or a Multiemployer Plan and
which is maintained or otherwise contributed to by any member of the ERISA
Group.

    "Borrower" means EOP Operating Limited Partnership, a Delaware limited
partnership.

    "Borrower's Share" means Borrower's and EOPT's direct or indirect share of
an Investment Affiliate based upon Borrower's and EOPT's percentage ownership
(whether direct or indirect) of such Investment Affiliate.

    "Borrowing" has the meaning set forth in Section 1.3.



                                       4
<PAGE>   9

    "Business Day" means any day except a Saturday, Sunday or other day on which
commercial banks in Dallas, Texas are authorized by law to close.

    "Capital Leases" as applied to any Person, means any lease of any property
(whether real, personal or mixed) by that Person as lessee which, in conformity
with GAAP, is or should be accounted for as a capital lease on the balance sheet
of that Person.

    "Cash or Cash Equivalents" shall mean (a) cash; (b) marketable direct
obligations issued or unconditionally guaranteed by the United States Government
or issued by an agency thereof and backed by the full faith and credit of the
United States, in each case maturing within one (1) year after the date of
acquisition thereof; (c) marketable direct obligations issued by any state of
the United States of America or any political subdivision of any such state or
any public instrumentality thereof maturing within ninety (90) days after the
date of acquisition thereof and, at the time of acquisition, having one of the
two highest ratings obtainable from any two of S & P, Moody's, Duff or Fitch
(or, if at any time no two of the foregoing shall be rating such obligations,
then from such other nationally recognized rating services acceptable to
Administrative Agent ); (d) domestic corporate bonds, other than domestic
corporate bonds issued by Borrower or any of its Affiliates, maturing no more
than two (2) years after the date of acquisition thereof and, at the time of
acquisition, having a rating of at least A or the equivalent from any two (2) of
S & P, Moody's, Duff or Fitch (or, if at any time no two of the foregoing shall
be rating such obligations, then from such other nationally recognized rating
services acceptable to Administrative Agent); (e) variable-rate domestic
corporate notes or medium term corporate notes, other than notes issued by
Borrower or any of its Affiliates, maturing or resetting no more than one (1)
year after the date of acquisition thereof and having a rating of at least AA or
the equivalent from two of S & P, Moody's, Duff or Fitch (or, if at any time no
two of the foregoing shall be rating such obligations, then from such other
nationally recognized rating services acceptable to Administrative Agent); (f)
commercial paper (foreign and domestic) or master notes, other than commercial
paper or master notes issued by Borrower or any of its Affiliates, and, at the
time of acquisition, having a long-term rating of at least A or the equivalent
from S & P, Moody's, Duff or Fitch and having a short-term rating of at least
A-1 and P-1 from S & P and Moody's, respectively (or, if at any time neither S &
P nor Moody's shall be rating such obligations, then the highest rating from
such other nationally recognized rating services acceptable to Administrative
Agent); (g) domestic and Eurodollar certificates of deposit or domestic time
deposits or Eurodollar deposits or bankers' acceptances (foreign or domestic)
that are issued by a bank (I) which has, at the time of acquisition, a long-term
rating of at least A or the equivalent from S & P, Moody's, Duff or Fitch and
(II) if a domestic bank, which is a member of the Federal Deposit Insurance
Corporation; and (h) overnight securities repurchase agreements, or reverse
repurchase agreements secured by any of the foregoing types of securities or
debt instruments, provided that the collateral supporting such repurchase
agreements shall have a value not less than 101% of the principal amount of the
repurchase agreement plus accrued interest.

    "Cash Flow" means, for any period, EBITDA for such period, as adjusted for a
normalized recurring level of capital expenditures by Borrower for such period,
which adjustment shall be at the rate of One Dollar and Fifty cents ($1.50) per
square foot per annum of office space leased as of the applicable date of
determination for (i) all Office Properties of Borrower and Consolidated
Subsidiaries, and (ii) Borrower's Share of each Office Property of an Investment
Affiliate (provided that, as to any Office Property acquired during such period



                                       5
<PAGE>   10

such $1.50 per square foot adjustment shall be pro-rated for the period of
ownership).

    "Closing Date" means the date on or after the Effective Date on which the
conditions set forth in Section 3.1 shall have been satisfied to the
satisfaction of the Administrative Agent and the Documentation Agent.

    "Co-Agents" means Credit Lyonnais, New York Branch, Fleet National Bank, and
U.S. Bank National Association, in their capacity as Co-Agents hereunder.

    "Code" shall mean the Internal Revenue Code of 1986, as amended, and as it
may be further amended from time to time, any successor statutes thereto, and
applicable U.S. Department of Treasury regulations issued pursuant thereto in
temporary or final form.

    "Committed Borrowing" has the meaning set forth in Section 1.3.

    "Committed Loan" means a loan made by a Bank pursuant to Section 2.1;
provided that, if any such loan or loans (or portions thereof) are combined or
subdivided pursuant to a Notice of Interest Rate Election, the term "Committed
Loan" shall refer to the combined principal amount resulting from such
combination or to each of the separate principal amounts resulting from such
subdivision, as the case may be.

    "Commitment" means with respect to each Bank, the amount set forth under the
name of such Bank on the signature pages hereof (and, for each Bank which is an
Assignee, the amount set forth in the Transfer Supplement entered into pursuant
to Section 9.6(c) as the Assignee's Commitment), as such amount may be reduced
from time to time pursuant to Section 2.11(c) or in connection with an
assignment to an Assignee, and as such amount may be increased pursuant to
Section 2.16.

    "Consolidated Subsidiary" means at any date any Subsidiary or other entity
which is consolidated with Borrower or EOPT in accordance with GAAP.

    "Consolidated Tangible Net Worth" means, at any time, the tangible net worth
of Borrower, on a consolidated basis, determined in accordance with GAAP, plus
all accumulated depreciation and amortization of Borrower plus Borrower's Share
of accumulated depreciation and amortization of Investment Affiliates, deducted,
in either case, from earnings in calculating Net Income.

    "Contingent Obligation" as to any Person means, without duplication, (i) any
contingent obligation of such Person required to be shown on such Person's
balance sheet in accordance with GAAP, and (ii) any obligation required to be
disclosed in the footnotes to such Person's financial statements, guaranteeing
partially or in whole any Non-Recourse Indebtedness, lease, dividend or other
obligation, exclusive of contractual indemnities (including, without limitation,
any indemnity or price-adjustment provision relating to the purchase or sale of
securities or other assets) and guarantees of non-monetary obligations (other
than guarantees of completion) which have not yet been called on or quantified,
of such Person or of any other Person. The amount of any Contingent Obligation
described in clause (ii) shall be deemed to be (a) with respect to a guaranty of
interest or interest and principal, or operating income guaranty, the Net
Present Value of the sum of all payments required to be made thereunder (which
in the case of an operating income guaranty shall be deemed to be equal to the
debt service for the note secured thereby), calculated at the Applicable




                                       6
<PAGE>   11


Interest Rate, through (i) in the case of an interest or interest and principal
guaranty, the stated date of maturity of the obligation (and commencing on the
date interest could first be payable thereunder), or (ii) in the case of an
operating income guaranty, the date through which such guaranty will remain in
effect, and (b) with respect to all guarantees not covered by the preceding
clause (a), an amount equal to the stated or determinable amount of the primary
obligation in respect of which such guaranty is made or, if not stated or
determinable, the maximum reasonably anticipated liability in respect thereof
(assuming such Person is required to perform thereunder) as recorded on the
balance sheet and on the footnotes to the most recent financial statements of
Borrower required to be delivered pursuant to Section 5.1 hereof.
Notwithstanding anything contained herein to the contrary, guarantees of
completion shall not be deemed to be Contingent Obligations unless and until a
claim for payment or performance has been made thereunder, at which time any
such guaranty of completion shall be deemed to be a Contingent Obligation in an
amount equal to any such claim. Subject to the preceding sentence, (i) in the
case of a joint and several guaranty given by such Person and another Person
(but only to the extent such guaranty is recourse, directly or indirectly to
Borrower), the amount of the guaranty shall be deemed to be 100% thereof unless
and only to the extent that such other Person has delivered Cash or Cash
Equivalents to secure all or any part of such Person's guaranteed obligations
and (ii) in the case of a guaranty (whether or not joint and several) of an
obligation otherwise constituting Indebtedness of such Person, the amount of
such guaranty shall be deemed to be only that amount in excess of the amount of
the obligation constituting Indebtedness of such Person. Notwithstanding
anything contained herein to the contrary, "Contingent Obligations" shall be
deemed not to include guarantees of Unused Commitments or of construction loans
to the extent the same have not been drawn. All matters constituting "Contingent
Obligations" shall be calculated without duplication.

"Convertible Securities" means evidences of shares of stock, limited or general
partnership interests or other ownership interests, warrants, options, or other
rights or securities which are convertible into or exchangeable for, with or
without payment of additional consideration, common shares of beneficial
interest of EOPT or partnership interests of Borrower, as the case may be,
either immediately or upon the arrival of a specified date or the happening of a
specified event.

    "Credit Rating" means the rating assigned by the Rating Agencies to
Borrower's senior unsecured long term indebtedness.

    "Debt Restructuring" means a restatement of, or material change in, the
amortization or other financial terms of any Indebtedness of EOPT, the Borrower
or any Subsidiary or Investment Affiliate.

    "Debt Service" means, for any period and without duplication, Interest
Expense for such period plus scheduled principal amortization (excluding Balloon
Payments) for such period on all Balance Sheet Indebtedness of Borrower on a
consolidated basis, plus Borrower's Share of scheduled principal amortization
(excluding Balloon Payments) for such period on all Balance Sheet Indebtedness
of Investment Affiliates.

    "Default" means any condition or event which with the giving of notice or
lapse of time or both would, unless cured or waived, become an Event of Default.

    "Default Rate" has the meaning set forth in Section 2.8(d).



                                       7
<PAGE>   12

    "Designated Lender" means a special purpose corporation that (i) shall have
become a party to this Agreement pursuant to Section 9.6(d), and (ii) is not
otherwise a Bank.

    "Designated Lender Notes" means promissory notes of the Borrower,
substantially in the form of Exhibit A-1 hereto, evidencing the obligation of
the Borrower to repay Money Market Loans made by Designated Lenders, and
"Designated Lender Note" means any one of such promissory notes issued under
Section 9.6(d) hereof.

    "Designating Lender" shall have the meaning set forth in Section 9.6(d)
hereof.

    "Designation Agreement" means a designation agreement in substantially the
form of Exhibit G attached hereto, entered into by a Bank and a Designated
Lender and accepted by the Lead Agent.

    "Development Activity" means (a) the development and construction of office
buildings and parking facilities by the Borrower or any of its Financing
Partnerships or Joint Venture Subsidiaries excluding Unimproved Assets, (b) the
financing by the Borrower or any of its Financing Partnerships or Joint Venture
Subsidiaries of any such development or construction and (c) the incurrence by
the Borrower or any of its Financing Partnerships or Joint Venture Subsidiaries
of any Contingent Obligations in connection with such development or
construction (other than purchase contracts for Real Property Assets which are
not payable until after completion of development or construction). For purposes
of Section 5.8(j) hereof, the "value" of Development Activity shall mean (i) in
the case of the development and construction by the Borrower or any of its
Financing Partnerships described in clause (a) of this definition, the full cost
budget to complete such development and construction, (ii) in the case of the
development and construction by a Joint Venture Subsidiary of the Borrower
described in clause (a) of this definition, an amount equal to the product of
(AA) the full cost budget to complete such development and construction,
multiplied by (BB) Borrower's Share of such Joint Venture Subsidiary, (iii) in
the case of the financing of any development and construction by the Borrower or
any of its Financing Partnerships described in clause (b) of this definition,
the amount the Borrower or any Financing Partnership has committed to fund to
pay the cost to complete such development and construction, (iv) in the case of
the financing of any development and construction by a Joint Venture Subsidiary
of the Borrower described in clause (b) of this definition, an amount equal to
the product of (AA) the amount such Joint Venture Subsidiary has committed to
fund to pay the cost to complete such development and construction, multiplied
by (B) Borrower's Share of such Joint Venture Subsidiary, (v) in the case of the
incurrence of any Contingent Obligations in connection with any development and
construction by the Borrower or any of its Financing Partnerships described in
clause (c) of this definition, the amount of such Contingent Obligation of the
Borrower or such Financing Partnership, (vi) in the case of the incurrence of
any Contingent Obligations in connection with any development and construction
by a Joint Venture Subsidiary of the Borrower described in clause (c) of this
definition, an amount equal to the product of (AA) the amount of such Contingent
Obligation of such Joint Venture Subsidiary, multiplied by (BB) Borrower's Share
of such Joint Venture Subsidiary..

    "Documentation Agent" means Bank of America, National Trust and Savings
Association, in its capacity as Documentation Agent hereunder, and its permitted
successors in such capacity in accordance with the terms of this Agreement.




                                       8
<PAGE>   13

    "Domestic Lending Office" means, as to each Bank, its office located at its
address in the United States set forth in its Administrative Questionnaire (or
identified in its Administrative Questionnaire as its Domestic Lending Office)
or such other office as such Bank may hereafter designate as its Domestic
Lending Office by notice to the Borrower and the Administrative Agent.

    "Duff" means Duff & Phelps Credit Rating Company, or any successor thereto.

    "EBITDA" means, for any period (i) Net Income for such period, plus (ii)
depreciation and amortization expense and other non-cash items deducted in the
calculation of Net Income for such period, plus (iii) Interest Expense deducted
in the calculation of Net Income for such period, plus (iv) Taxes (net of any
Taxes actually paid to, or withheld by, any foreign jurisdiction with respect to
any Real Property Asset located outside of the United States) deducted in the
calculation of Net Income for such period, plus (v) Borrower's Share of the
Investment Affiliate EBITDA for each Investment Affiliate, minus (vi) the gains
(and plus the losses) from extraordinary items or asset sales or write-ups or
forgiveness of indebtedness included (or deducted) in the calculation of Net
Income for such period, all of the foregoing without duplication.

    "Effective Date" means the date this Agreement becomes effective in
accordance with Section 9.9.

    "Environmental Affiliate" means any partnership, joint venture, trust or
corporation in which an equity interest is owned directly or indirectly by the
Borrower and, as a result of the ownership of such equity interest, Borrower may
have recourse liability for Environmental Claims against such partnership, joint
venture, trust or corporation (or the property thereof).

    "Environmental Claim" means, with respect to any Person, any notice, claim,
demand or similar communication (written or oral) by any other Person alleging
potential liability of such Person for investigatory costs, cleanup costs,
governmental response costs, natural resources damage, property damages,
personal injuries, fines or penalties arising out of, based on or resulting from
(i) the presence, or release into the environment, of any Materials of
Environmental Concern at any location, whether or not owned by such Person or
(ii) circumstances forming the basis of any violation, or alleged violation, of
any Environmental Law, in each case (with respect to both (i) and (ii) above) as
to which there is a reasonable possibility of an adverse determination with
respect thereto and which, if adversely determined, would have a Material
Adverse Effect on the Borrower.

    "Environmental Laws" means any and all federal, state, and local statutes,
laws, judicial decisions, regulations, ordinances, rules, judgments, orders,
decrees, plans, injunctions, permits, concessions, grants, licenses, agreements
and other governmental restrictions relating to the environment, the effect of
the environment on human health or to emissions, discharges or releases of
Materials of Environmental Concern into the environment including, without
limitation, ambient air, surface water, ground water, or land, or otherwise
relating to the manufacture, processing, distribution, use, treatment, storage,
disposal, transport or handling of Materials of Environmental Concern or the
clean up or other remediation thereof.




                                       9
<PAGE>   14

    "EOPT" means Equity Office Properties Trust, a Maryland real estate
investment trust, the sole managing general partner of the Borrower.

    "EOPT Guaranty" means (i) the Amended and Restated Guaranty of Payment --
No. 1, dated as of even date herewith, executed by and between EOPT and
Administrative Agent for the benefit of the Banks, and (ii) the Amended and
Restated Guaranty of Payment -- No. 2, dated as of even date herewith, executed
by and between EOPT and Administrative Agent for the benefit of the Banks. All
uses herein of the term "EOPT Guaranty" shall be deemed to refer to each of the
guarantees listed in clauses (i) and (ii) above individually and to both such
guarantees collectively.

    "ERISA" means the Employee Retirement Income Security Act of 1974, as
amended, or any successor statute.

    "ERISA Group" means the Borrower, any Subsidiary, EOPT and all members of a
controlled group of corporations and all trades or businesses (whether or not
incorporated) under common control and all members of an "affiliated service
group" which, together with the Borrower, any Subsidiary or EOPT, are treated as
a single employer under Section 414 of the Code or Section 4001(b)(1) of ERISA.

    "Euro-Dollar Borrowing" has the meaning set forth in Section 1.3.

    "Euro-Dollar Lending Office" means, as to each Bank, its office, branch or
affiliate located at its address set forth in its Administrative Questionnaire
(or identified in its Administrative Questionnaire as its Euro-Dollar Lending
Office) or such other office, branch or affiliate of such Bank as it may
hereafter designate as its Euro-Dollar Lending Office by notice to the Borrower
and the Administrative Agent.

    "Euro-Dollar Loan" means a Committed Loan to be made by a Bank as a
Euro-Dollar Loan in accordance with the applicable Notice of Borrowing.

    "Euro-Dollar Reference Bank"" means the principal Dallas offices of the
Administrative Agent.

    "Euro-Dollar Reserve Percentage" means for any day that percentage
(expressed as a decimal) which is in effect on such day, as prescribed by the
Board of Governors of the Federal Reserve System (or any successor) under
Regulation D, as Regulation D may be amended, modified or supplemented, for
determining the maximum reserve requirement for a member bank of the Federal
Reserve System in New York City with deposits exceeding five billion dollars in
respect of "Eurocurrency liabilities" (or in respect of any other category of
liabilities which includes deposits by reference to which the interest rate on
Euro-Dollar Loans is determined or any category of extensions of credit or other
assets which includes loans by a non-United States office of any Bank to United
States residents). The Adjusted Interbank Offered Rate shall be adjusted
automatically on and as of the effective date of any change in the Euro-Dollar
Reserve Percentage.

    "Event of Default" has the meaning set forth in Section 6.1.

    "Existing Credit Agreement" has the meaning set forth in the Recitals
hereto.

    "Federal Funds Rate" means, for any day, the rate per annum (rounded upward,
if necessary, to the nearest 1/100th of 1%) equal to the weighted average of the



                                       10
<PAGE>   15

rates on overnight Federal funds transactions with members of the Federal
Reserve System arranged by Federal funds brokers on such day, as published by
the Federal Reserve Bank of New York on the Business Day next succeeding such
day, provided that (i) if such day is not a Business Day, the Federal Funds Rate
for such day shall be such rate on such transactions on the next preceding
Business Day as so published on the next succeeding Business Day, and (ii) if no
such rate is so published on such next succeeding Business Day, the Federal
Funds Rate for such day shall be the average rate quoted to the Administrative
Agent on such day on such transactions as determined by the Administrative
Agent.

    "Federal Reserve Board" means the Board of Governors of the Federal Reserve
System as constituted from time to time.

    "FFO" means "funds from operations," defined to mean, without duplication
for any period, Net Income, plus (i) Borrower's Share of the Net Income of any
Investment Affiliate (plus Borrower's Share of real estate depreciation and
amortization expenses of Investment Affiliates), plus (ii) real estate
depreciation and amortization expense for such period, plus (iii) any
amortization of loan discount deducted from the calculation of Net Income for
such period, plus (iv) Taxes deducted from the calculation of Net Income for
such period, minus (v) gains (and plus the losses) from Debt Restructurings and
sales or other dispositions of Property of the Borrower or any Subsidiary or
Investment Affiliate included (or deducted) in the calculation of Net Income for
such period.

    "Financing Partnerships" means any Subsidiary which is wholly-owned,
directly or indirectly, by Borrower or by Borrower and EOPT, with EOPT holding,
directly or indirectly other than through its interest in Borrower, no more than
a 2% economic interest in such Subsidiary.

    "Fiscal Quarter" means a fiscal quarter of a Fiscal Year.

    "Fiscal Year" means the fiscal year of Borrower and EOPT.

    "Fitch" means Fitch Investors Services, Inc., or any successor thereto.

    "Fixed Charges" for any Fiscal Quarter period means the sum of (i) Debt
Service for such period, (ii) dividends on preferred units payable by Borrower
for such period, and (iii) distributions made by Borrower in such period to EOPT
for the purpose of paying dividends on preferred shares in EOPT.

    "Fixed Rate Borrowing" has the meaning set forth in Section 1.3.

    "Fixed Rate Indebtedness" means all Indebtedness which accrues interest at a
fixed rate.

    "Floating Rate Indebtedness" means all Indebtedness which is not Fixed Rate
Indebtedness and which is not a Contingent Obligation or an Unused Commitment.

    "Form S-11" means the Form S-11 Registration Statement filed by EOPT with
the Securities and Exchange Commission on May 7, 1997, as amended.

    "GAAP" means generally accepted accounting principles recognized as such in
the opinions and pronouncements of the Accounting Principles Board and the
American Institute of Certified Public Accountants and the Financial Accounting
Standards Board or in such other statements by such other entity as may be



                                       11
<PAGE>   16

approved by a significant segment of the accounting profession, which are
applicable to the circumstances as of the date of determination.

    "Group of Loans" means, at any time, a group of Loans consisting of (i) all
Committed Loans which are Base Rate Loans at such time, or (ii) all Euro-Dollar
Loans having the same Interest Period at such time; provided that, if a
Committed Loan of any particular Bank is converted to or made as a Base Rate
Loan pursuant to Section 8.2 or 8.5, such Loan shall be included in the same
Group or Groups of Loans from time to time as it would have been in if it had
not been so converted or made.

    "IBOR Auction" means a solicitation of Money Market Quotes setting forth
Money Market Margins based on the Interbank Offered Rate pursuant to Section
2.4.

    "Interbank Offered Rate" applicable to any Interest Period means the average
(rounded upward, if necessary, to the next higher 1/16 of 1%) of the respective
rates per annum at which deposits in dollars are offered to the Euro-Dollar
Reference Bank in the interbank market at approximately 11:00 a.m. (Dallas time)
two Business Days before the first day of such Interest Period in an amount
approximately equal to the principal amount of the Euro-Dollar Borrowing or
Group of Loans or portion thereof to be converted into or continued as
Euro-Dollar Loans to which such Interest Period is to apply and for a period of
time comparable to such Interest Period.


    "Indebtedness" as applied to any Person (and without duplication), means (a)
all indebtedness, obligations or other liabilities of such Person for borrowed
money, (b) all indebtedness, obligations or other liabilities of such Person
evidenced by Securities or other similar instruments, (c) all Contingent
Obligations of such Person, (d) all reimbursement obligations and other
liabilities of such Person with respect to letters of credit or banker's
acceptances issued for such Person's account or other similar instruments for
which a contingent liability exists, (e) all obligations of such Person to pay
the deferred purchase price of Property or services, (f) all obligations in
respect of Capital Leases (including, without limitation, ground leases to the
extent such ground leases constitute Capital Leases) of such Person, (g) all
indebtedness obligations or other liabilities of such Person or others secured
by a Lien on any asset of such Person, whether or not such indebtedness,
obligations or liabilities are assumed by, or are a personal liability of such
Person, (h) all indebtedness, obligations or other liabilities (other than
interest expense liability) in respect of Interest Rate Contracts and foreign
currency exchange agreements (other than Interest Rate Contracts purchased to
hedge Indebtedness), to the extent such liabilities are material and are
reported or are required under GAAP to be reported by such Person in its
financial statements, (i) ERISA obligations currently due and payable and (j)
all other items which, in accordance with GAAP, would be included as liabilities
on the liability side of the balance sheet of such Person.

    "Indemnitee" has the meaning set forth in Section 9.3(b).

    "Interest Expense" means, for any period and without duplication, total
interest expense, whether paid, accrued or capitalized of Borrower, on a
consolidated basis determined in accordance with GAAP, plus Borrower's Share of
accrued, paid or capitalized interest with respect to any Balance Sheet
Indebtedness of Investment Affiliates (in each case, including, without





                                       12
<PAGE>   17

limitation, the interest component of Capital Leases but excluding interest
expense covered by an interest reserve established under a loan facility such as
capitalized construction interest provided for in a construction loan).

    "Interest Period" means: (1) with respect to each Euro-Dollar Borrowing, the
period commencing on the date of such Borrowing specified in the Notice of
Borrowing or on the date specified in the applicable Notice of Interest Rate
Election and ending 30, 60, 90, or 180 days thereafter (or a period less than 30
days with the reasonable approval of Administrative Agent, unless any Bank has
previously advised Administrative Agent and Borrower that it is unable to enter
into Interbank Offered Rate Contracts for an Interest Period of the same
duration) as the Borrower may elect in the applicable Notice of Borrowing or
Notice of Interest Rate Election; provided that:

                  (a) any Interest Period which would otherwise end on a day
     which is not a Business Day shall be extended to the next succeeding
     Business Day unless such Business Day falls in another calendar month, in
     which case such Interest Period shall end on the next preceding Business
     Day;

                  (b) any Interest Period which begins on the last Business Day
     of a calendar month (or on a day for which there is no numerically
     corresponding day in the calendar month at the end of such Interest Period)
     shall end on the last Business Day of a calendar month; and

                  (c) no Interest Period may end later than the Maturity Date.

(2) with respect to each Base Rate Borrowing and solely for determining when
interest is payable on any Base Rate Borrowing, the period commencing on the
date of such Borrowing specified in the Notice of Borrowing or on the date
specified (or deemed specified) in the applicable Notice of Interest Rate
Election and ending 30 days thereafter; provided that:

                  (a) any Interest Period which would otherwise end on a day
     which is not a Business Day shall be extended to the next succeeding
     Business Day; and

                  (b) no Interest Period may end later than the Maturity Date.

(3) with respect to each Money Market IBOR Loan, the period commencing on the
date of borrowing specified in the applicable Money Market Quote Request and
ending such number of months thereafter as the Borrower may elect in accordance
with Section 2.4; provided that:

                  (a) any Interest Period which would otherwise end on a day
     which is not a Business Day shall be extended to the next succeeding
     Business Day unless such Business Day falls in another calendar month, in
     which case such Interest Period shall end on the next preceding Business
     Day;

                  (b) any Interest Period which begins on the last Business Day
     of a calendar month (or on a day for which there is no numerically
     corresponding day in the calendar month at the end of such Interest Period)
     shall, subject to clause (c) below, end on the last Business Day of a
     calendar month; and




                                       13
<PAGE>   18

                  (c) no Interest Period may end later than the Maturity. (4)
with respect to each Money Market Absolute Rate Loan, the period commencing on
the date of borrowing specified in the applicable Money Market Quote Request and
ending such number of days thereafter (but not less than 14 days or more than
180 days) as the Borrower may elect in accordance with Section 2.4; provided
that:

                  (a) any Interest Period which would otherwise end on a day
     which is not a Business Day shall be extended to the next succeeding
     Business Day; and

                  (b) no Interest Period may end later than the Maturity Date.

    "Interest Rate Contracts" means, collectively, interest rate swap, collar,
cap or similar agreements providing interest rate protection.

    "Investment Affiliate" means any Person in whom EOPT or Borrower holds an
equity interest, directly or indirectly, whose financial results are not
consolidated under GAAP with the financial results of EOPT or Borrower on the
consolidated financial statements of EOPT and Borrower.

    "Investment Affiliate EBITDA" means, for any period (i) the net earnings (or
loss) of an Investment Affiliate for such period calculated in conformity with
GAAP, plus (ii) depreciation and amortization expense and other non-cash items
of such Investment Affiliate deducted in the calculation of such net earnings
(or loss) for such period, plus (iii) total interest expense, whether paid,
accrued or capitalized, of such Investment Affiliate deducted in the calculation
of such net earnings (or loss) for such period, plus (iv) Taxes of such
Investment Affiliate deducted in the calculation of such net earnings (or loss)
for such period.

    "Investment Grade Rating" means a rating for a Person's senior long-term
unsecured debt of BBB- or better from S&P or a rating of Baa3 or better from
Moody's. In the event that Borrower receives Credit Ratings only from S&P and
Moody's, and such Credit Ratings are not equivalent, the lower of such two (2)
Credit Ratings shall be used to determine whether an Investment Grade Rating was
achieved. In the event that Borrower receives more than two (2) Credit Ratings,
and such Credit Ratings are not all equivalent, the higher of the ratings from
S&P and Moody's shall be used to determine whether an Investment Grade Rating
was achieved, provided that the rating from one of the other Rating Agencies
shall be at least equivalent to such higher rating; provided, further, that if
the rating from one of the other Rating Agencies is not at least equivalent to
the higher of the ratings from S&P and Moody's, then the second (2nd) highest
Credit Rating shall be used to determine whether an Investment Grade Rating was
achieved.

    "Investment Mortgages" means mortgages securing indebtedness with respect to
Office Properties and Parking Properties directly or indirectly owed to Borrower
or any of its Subsidiaries, including, without limitation, certificates of
interest in real estate mortgage investment conduits.

    "Invitation for Money Market Quotes" has the meaning set forth in Section
2.4(c).

    "Joint Venture Interests" means partnership or joint venture interests
issued by any Person which is an Investment Affiliate that is not a Subsidiary.



                                       14
<PAGE>   19

    "Joint Venture Parent" means Borrower or one or more Financing Partnerships
of Borrower which directly owns any interest in a Joint Venture Subsidiary.

    "Joint Venture Subsidiary" means any entity (other than a Financing
Partnership) in which (i) a Joint Venture Parent owns at least 50% of the
economic interests and (ii) the sale or financing of any Property owned by such
Joint Venture Subsidiary is controlled by a Joint Venture Parent. For purposes
of this definition, the Borrower shall be deemed to "control" Civic Parking,
L.L.C., a Missouri limited liability company ("Civic") so long as (i) a Joint
Venture Parent owns at least 50% of economic interest therein and (ii) such
Joint Venture Parent's consent shall be required to authorize and approve the
sale or financing of the Property owned by Civic.

    "Lien" means, with respect to any asset, any mortgage, lien, pledge, charge,
security interest or encumbrance of any kind, or any other type of preferential
arrangement, in each case that has the effect of creating a security interest,
in respect of such asset. For the purposes of this Agreement, the Borrower or
any Consolidated Subsidiary shall be deemed to own subject to a Lien any asset
which it has acquired or holds subject to the interest of a vendor or lessor
under any conditional sale agreement, capital lease or other title retention
agreement relating to such asset.

    "Loan" means a Base Rate Loan, a Euro-Dollar Loan, a Money Market Loan or a
Swingline Loan and "Loans" means Base Rate Loans, Euro-Dollar Loans, Money
Market Loans or Swingline Loans or any combination of the foregoing.

    "Loan Documents" means this Agreement, the Notes, the EOPT Guaranty, and the
Acorn Guaranty (as defined in the EOPT Guaranty).

    "Majority Banks" means at any time Banks having at least 51% of the
aggregate amount of Commitments, or if the Commitments shall have been
terminated, holding Notes evidencing at least 51% of the aggregate unpaid
principal amount of the Loans, (provided, that in the case of Swingline Loans,
the amount of each Bank's funded participation interest in such Swingline Loans
shall be considered for purposes hereof as if it were a direct loan and not a
participation interest, and the aggregate amount of Swingline Loans owing to the
Swingline Lender shall be considered for purposes hereof as reduced by the
amount of such funded participation interests).

    "Managing Agents" means The Bank of Nova Scotia, The Chase Manhattan Bank,
Commerzbank Aktiengesellschaft, Dresdner Bank AG, New York and Cayman Branches,
PNC Bank, National Association, and Union Bank of Switzerland, New York Branch,
in their capacity as Managing Agents hereunder.

    "Mandatory Borrowing" has the meaning set forth in Section 2.3(b)(iii).

    "Material Adverse Effect" means an effect resulting from any circumstance or
event or series of circumstances or events, of whatever nature (but excluding
general economic conditions), which does or could reasonably be expected to,
materially and adversely (i) impair the ability of the Borrower and its
Consolidated Subsidiaries, taken as a whole, to perform their respective
obligations under the Loan Documents, or (ii) the ability of Administrative
Agent, Documentation Agent or the Banks to enforce the Loan Documents.




                                       15
<PAGE>   20

    "Material Plan" means at any time a Plan or Plans having aggregate unfunded
liabilities in excess of $5,000,000.

         "Materials of Environmental Concern" means and includes pollutants,
contaminants, hazardous wastes, toxic and hazardous substances, asbestos, lead,
petroleum and petroleum by-products.

    "Maturity Date" shall mean the date when all of the Obligations hereunder
shall be due and payable which shall be May 29, 2001, unless accelerated
pursuant to the terms hereof.

    "Money Market Absolute Rate" has the meaning set forth in Section 2.4(d)(2).

    "Money Market Absolute Rate Loan" means a loan to be made by a Bank pursuant
to an Absolute Rate Auction.

    "Money Market Borrowing" has the meaning set forth in Section 1.3.

    "Money Market Lending Office" means, as to each Bank, its Domestic Lending
Office or such other office, branch or affiliate of such Bank as it may
hereafter designate as its Money Market Lending Office by notice to the Borrower
and the Agent; provided that any Bank may from time to time by notice to the
Borrower and the Administrative Agent designate separate Money Market Lending
Offices for its Money Market IBOR Loans, on the one hand, and its Money Market
Absolute Rate Loans, on the other hand, in which case all references herein to
the Money Market Lending Office of such Bank shall be deemed to refer to either
or both of such offices, as the context may require.

    "Money Market LIBOR Loan" means a loan to be made by a Bank pursuant to a
IBOR Auction (including, without limitation, such a loan bearing interest at the
Base Rate pursuant to Article VIII).

    "Money Market Loan" means a Money Market IBOR Loan or a Money Market
Absolute Rate Loan. "Money Market Margin" has the meaning set forth in Section
2.4(d)(2).

    "Money Market Quote" means an offer by a Bank to make a Money Market Loan in
accordance with Section 2.4.

    "Money Market Quote Request" has the meaning set forth in Section 2.4(b).

    "Moody's" means Moody's Investors Services, Inc. or any successor thereto.

    "Multiemployer Plan" means at any time an employee pension benefit plan
within the meaning of Section 4001(a)(3) of ERISA to which any member of the
ERISA Group is then making or accruing an obligation to make contributions or
has at any time after September 25, 1980 made contributions or has been required
to make contributions (for these purposes any Person which ceased to be a member
of the ERISA Group after September 25, 1980 will be treated as a member of the
ERISA Group).

    "Negative Pledge" means, with respect to any Property, any covenant,
condition, or other restriction which prohibits or limits the creation or
assumption of any Lien upon such Property to secure any or all of the
Obligations.


                                       16
<PAGE>   21

    "Net Income" means, for any period, the net earnings (or loss) after Taxes
of the Borrower, on a consolidated basis, before the deduction of minority
interests and before the deduction of payment of any preferred dividends, for
such period calculated in conformity with GAAP.

    "Net Offering Proceeds" means all cash or other assets received by EOPT or
Borrower as a result of the sale of common shares of beneficial interest,
preferred shares of beneficial interest, partnership interests, limited
liability company interests, Convertible Securities or other ownership or equity
interests in EOPT or Borrower less customary costs and discounts of issuance
paid by EOPT or Borrower, as the case may be.

    "Net Price" means, with respect to the purchase of any Property, without
duplication, (i) the aggregate purchase price paid as cash consideration for
such purchase (without adjustment for prorations), including, without
limitation, the principal amount of any note received or other deferred payment
to be made in connection with such purchase (except as described in clause (ii)
below) and the value of any non-cash consideration delivered in connection with
such purchase (including, without limitation, shares or preferred shares of
beneficial interest in EOPT and OP Units or Preferred OP Units (as defined in
Borrower's partnership agreement)) plus (ii) reasonable costs of sale and
non-recurring taxes paid or payable in connection with such purchase or sale.

    "Net Present Value" shall mean, as to a specified or ascertainable dollar
amount, the present value, as of the date of calculation of any such amount
using a discount rate equal to the Base Rate in effect as of the date of such
calculation.

    "Non-Recourse Indebtedness" means Indebtedness with respect to which
recourse for payment is limited to (i) specific assets related to a particular
Property or group of Properties encumbered by a Lien securing such Indebtedness
or (ii) any Subsidiary (provided that if a Subsidiary is a partnership, there is
no recourse to Borrower or EOPT as a general partner of such partnership);
provided, however, that personal recourse of Borrower or EOPT for any such
Indebtedness for fraud, misrepresentation, misapplication of cash, waste,
environmental claims and liabilities and other circumstances customarily
excluded by institutional lenders from exculpation provisions and/or included in
separate indemnification agreements in non-recourse financing of real estate
shall not, by itself, prevent such Indebtedness from being characterized as
Non-Recourse Indebtedness.

    "Notes" means the amended and restated promissory notes of the Borrower,
substantially in the form of Exhibit A and Exhibit A-1 hereto, evidencing the
obligation of the Borrower to repay the Loans, and "Note" means any one of such
promissory notes issued hereunder. The Notes shall be issued in substitution for
the "Notes" issued pursuant to the Existing Credit Agreement.

    "Notice of Borrowing" means a notice from Borrower in accordance with
Section 2.2 or Section 2.3(b)(i).

    "Notice of Interest Rate Election" has the meaning set forth in Section 2.7.

    "Obligations" means all obligations, liabilities, indemnity obligations and
Indebtedness of every nature of the Borrower, from time to time owing to
Administrative Agent, Documentation Agent or any Bank under or in connection
with this Agreement or any other Loan Document.


                                       17
<PAGE>   22

    "Office Property" means any Property which constitutes primarily commercial
office space other than a Parking Property.

    "Original Closing Date" means the "Closing Date" as defined in the Existing
Credit Agreement.

    "Parking Property" means any Property which is primarily used for parking.

    "Parent" means, with respect to any Bank, any Person controlling such Bank.

    "Participant" has the meaning set forth in Section 9.6(b).

    "PBGC" means the Pension Benefit Guaranty Corporation or any entity
succeeding to any or all of its functions under ERISA.

    "Permitted Holdings" means Unimproved Assets, Development Activity, Joint
Venture Interests, Investment Mortgages and Securities, but only to the extent
permitted in Section 5.8.

    "Permitted Liens" means:

         a. Liens for Taxes, assessments or other governmental charges not yet
    due and payable or which are being contested in good faith by appropriate
    proceedings promptly instituted and diligently conducted in accordance with
    the terms hereof;

         b. statutory liens of carriers, warehousemen, mechanics, materialmen
    and other similar liens imposed by law, which are incurred in the ordinary
    course of business for sums not more than sixty (60) days delinquent or
    which are being contested in good faith in accordance with the terms hereof;

         c.   deposits made in the ordinary course of business to secure
    liabilities to insurance carriers;

         d. Liens for purchase money obligations for equipment; provided that
    (i) the Indebtedness secured by any such Lien does not exceed the purchase
    price of such equipment, (ii) any such Lien encumbers only the asset so
    purchased and the proceeds upon sale, disposition, loss or destruction
    thereof, and (iii) such Lien, after giving effect to the Indebtedness
    secured thereby, does not give rise to an Event of Default;

         e. easements, rights-of-way, zoning restrictions, other similar charges
    or encumbrances and all other items listed on Schedule B to Borrower's
    owner's title insurance policies, except in connection with any
    Indebtedness, for any of Borrower's Real Property Assets, so long as the
    foregoing do not interfere in any material respect with the use or ordinary
    conduct of the business of Borrower and do not diminish in any material
    respect the value of the Property to which it is attached or for which it is
    listed;

         f. Liens and judgments which have been or will be bonded or released of
    record within thirty (30) days after the date such Lien or judgment is
    entered or filed against EOPT, Borrower, or any Subsidiary;

         g. Liens on Property of the Borrower or its Subsidiaries (other than
    Qualifying Unencumbered Property) securing Indebtedness which may be


                                       18
<PAGE>   23

    incurred or remain outstanding without resulting in an Event of Default
    hereunder; and

         h.   Liens in favor of Borrower against any asset of any Financing
    Partnership or Joint Venture Subsidiaries.

    "Person" means an individual, a corporation, a partnership, an association,
a trust or any other entity or organization, including, without limitation, a
government or political subdivision or an agency or instrumentality thereof.

    "Plan" means at any time an employee pension benefit plan (other than a
Multiemployer Plan) which is covered by Title IV of ERISA or subject to the
minimum funding standards under Section 412 of the Code and either (i) is
maintained, or contributed to, by any member of the ERISA Group for employees of
any member of the ERISA Group or (ii) has at any time within the preceding five
years been maintained, or contributed to, by any Person which was at such time a
member of the ERISA Group for employees of any Person which was at such time a
member of the ERISA Group.

    "Prime Rate" means the rate of interest publicly announced by the
Administrative Agent from time to time as its Prime Rate (it being understood
that the same shall not necessarily be the best rate offered by the
Administrative Agent to customers).

    "Pro Rata Share" means, with respect to any Bank, a fraction (expressed as a
percentage), the numerator of which shall be the amount of such Bank's
Commitment and the denominator of which shall be the aggregate amount of all of
the Banks' Commitments, as adjusted from time to time in accordance with the
provisions of this Agreement.

    "Property" means, with respect to any Person, any real or personal property,
building, facility, structure, equipment or unit, or other asset owned by such
Person.

    "Qualified Institution" means a Bank, or one or more banks, finance
companies, insurance or other financial institutions which (A) has (or, in the
case of a bank which is a subsidiary, such bank's parent has) a rating of its
senior debt obligations of not less than Baa-1 by Moody's or a comparable rating
by a rating agency acceptable to Syndication Agent and (B) has total assets in
excess of Ten Billion Dollars ($10,000,000,000).

    "Qualifying Unencumbered Property" means any Property (excluding Unimproved
Assets) from time to time which (i) is an operating Office Property or Parking
Property wholly-owned (directly or beneficially) by Borrower, a Financing
Partnership or a Joint Venture Subsidiary, (ii) is not subject (nor are any
equity interests in such Property that are owned directly or indirectly by
Borrower, EOPT or any Joint Venture Parent subject) to a Lien which secures
Indebtedness of any Person other than Permitted Liens, (iii) is not subject (nor
are any equity interests in such Property that are owned directly or indirectly
by Borrower, EOPT or any Joint Venture Parent subject) to any Negative Pledge
(provided that a financial covenant given for the benefit of any Person that may
be violated by the granting of any Lien on any Property to secure any or all of
the Obligations shall not be deemed a Negative Pledge).

    "Rating Agencies" means, collectively, S&P, Moody's, Duff and Fitch.



                                       19
<PAGE>   24

    "Real Property Assets" means as to any Person as of any time, the real
property assets (including, without limitation, interests in participating
mortgages in which such Person's interest therein is characterized as equity
according to GAAP) owned directly or indirectly by such Person at such time.

    "Recourse Debt" shall mean Indebtedness that is not Non-Recourse
Indebtedness.

    "Regulation U" means Regulation U of the Board of Governors of the Federal
Reserve System, as in effect from time to time.

    "Required Banks" means at any time Banks having at least 66 2/3% of the
aggregate amount of the Commitments or, if the Commitments shall have been
terminated, holding Notes evidencing at least 66 2/3% of the aggregate unpaid
principal amount of the Loans (provided, that in the case of Swingline Loans,
the amount of each Bank's funded participation interest in such Swingline Loans
shall be considered for purposes hereof as if it were a direct loan and not a
participation interest, and the aggregate amount of Swingline Loans owing to the
Swingline Lender shall be considered for purposes hereof as reduced by the
amount of such funded participation interests).

    "S&P" means Standard & Poor's Ratings Services, a division of The
McGraw-Hill Companies, Inc., or any successor thereto.

    "Secured Debt" means Indebtedness, the payment of which is secured by a Lien
(other than a Permitted Lien, except for those Permitted Liens described in
clauses (d) and (g) of the definition thereof) on any Property owned or leased
by EOPT, Borrower, or any Consolidated Subsidiary plus Borrower's Share of
Indebtedness, the payment of which is secured by a Lien (other than a Permitted
Lien, except for those Permitted Liens described in clauses (d) and (g) of the
definition thereof) on any Property owned or leased by any Investment Affiliate.

    "Securities" means any stock, partnership interests, shares, shares of
beneficial interest, voting trust certificates, bonds, debentures, notes or
other evidences of indebtedness, secured or unsecured, convertible, subordinated
or otherwise, or in general any instruments commonly known as "securities," or
any certificates of interest, shares, or participations in temporary or interim
certificates for the purchase or acquisition of, or any right to subscribe to,
purchase or acquire any of the foregoing, but shall not include Joint Venture
Interests or any evidence of the Obligations.

    "Solvent" means, with respect to any Person, that the fair saleable value of
such Person's assets exceeds the Indebtedness of such Person.

    "Subsidiary" means any corporation or other entity of which securities or
other ownership interests having ordinary voting power to elect a majority of
the board of directors or other persons performing similar functions are at the
time directly or indirectly owned by the Borrower or EOPT.

    "Syndication Agent" means J.P. Morgan Securities Inc., in its capacity as
syndication agent hereunder and its permitted successors in such capacity in
accordance with the terms of this Agreement.

    "Swingline Borrowing" has the meaning set forth in Section 1.3.

    "Swingline Commitment" has the meaning set forth in Section 2.3(a).



                                       20
<PAGE>   25

    "Swingline Lender" means NationsBank, N.A., in its capacity as Swingline
Lender hereunder, and its permitted successors in such capacity in accordance
with the terms of this Agreement..

    "Swingline Loan" means a loan made by the Swingline Lender pursuant to
Section 2.3.

    "Taxes" means all federal, state, local and foreign income and gross
receipts taxes.

    "Term" has the meaning set forth in Section 2.10.

    "Term Loan Agreement" shall mean that certain Credit Agreement, dated as of
October 2, 1997, among the Borrower and the banks and agents listed therein,
providing for a term loan facility in the amount of $1,500,000,000.

    "Termination Event" shall mean (i) a "reportable event", as such term is
described in Section 4043 of ERISA (other than a "reportable event" not subject
to the provision for 30-day notice to the PBGC), or an event described in
Section 4062(e) of ERISA, (ii) the withdrawal by any member of the ERISA Group
from a Multiemployer Plan during a plan year in which it is a "substantial
employer" (as defined in Section 4001(a)(2) of ERISA), or the incurrence of
liability by any member of the ERISA Group under Section 4064 of ERISA upon the
termination of a Multiemployer Plan, (iii) the filing of a notice of intent to
terminate any Plan under Section 4041 of ERISA, other than in a standard
termination within the meaning of Section 4041 of ERISA, or the treatment of a
Plan amendment as a distress termination under Section 4041 of ERISA, (iv) the
institution by the PBGC of proceedings to terminate, impose liability (other
than for premiums under Section 4007 of ERISA) in respect of, or cause a trustee
to be appointed to administer, any Plan or (v) any other event or condition that
might reasonably constitute grounds for the termination of, or the appointment
of a trustee to administer, any Plan or the imposition of any liability or
encumbrance or Lien on the Real Property Assets or any member of the ERISA Group
under ERISA or the Code.

    "Total Asset Value" means, with respect to Borrower and without duplication,
(i) for any Properties owned by Borrower, any Consolidated Subsidiary or
Investment Affiliate which was neither acquired nor disposed of by Borrower, a
Consolidated Subsidiary or an Investment Affiliate in the Fiscal Quarter most
recently ended, the quotient obtained by dividing (a) (x) EBITDA attributable to
such Properties for the Fiscal Quarter most recently ended multiplied by four
(4) less (y) $0.20 per square foot of leased office space within such Properties
which are Office Properties, by (b) 0.0875, plus (ii) for any Property which was
acquired by Borrower or a Consolidated Subsidiary in the Fiscal Quarter most
recently ended, the Net Price of the Property paid by Borrower or the
Consolidated Subsidiary for such Property, plus (iii) for any Property which was
acquired by an Investment Affiliate in the Fiscal Quarter most recently ended,
Borrower's Share of the Net Price of the Property paid by such Investment
Affiliate for such Property, plus (iv) the value of any Cash or Cash Equivalent
owned by Borrower, plus (v) the value of any Unimproved Assets and any other
tangible assets of Borrower or its Consolidated Subsidiaries (including foreign
currency exchange agreements, to the extent such agreements are material and are
reported or are required under GAAP to be reported by the Borrower or its
Consolidated Subsidiaries in their financial statements), as measured on a GAAP
basis, plus (vi) Borrower's Share of the value of any Unimproved Assets and any
other tangible assets of any Investment Affiliate as measured on a GAAP basis.


                                       21
<PAGE>   26

    "Total Liabilities" means, as of the date of determination and without
duplication, all Balance Sheet Indebtedness of Borrower, on a consolidated
basis, plus Borrower's Share of all Balance Sheet Indebtedness of Investment
Affiliates.

    "Treasury Rate" means, as of any date, a rate equal to the annual yield to
maturity on the U.S. Treasury Constant Maturity Series with a ten year maturity,
as such yield is reported in Federal Reserve Statistical Release H.15 --
Selected Interest Rates, published most recently prior to the date the
applicable Treasury Rate is being determined. Such yield shall be determined by
straight line linear interpolation between the yields reported in Release H.15,
if necessary. In the event Release H.15 is no longer published, the
Administrative Agent shall select, in its reasonable discretion, an alternate
basis for the determination of Treasury yield for U.S. Treasury Constant
Maturity Series with ten year maturities.

    "Unencumbered Asset Value" means (i) for any Qualifying Unencumbered
Properties which were neither acquired or disposed of by Borrower, a Financing
Partnership or a Joint Venture Subsidiary in the Fiscal Quarter most recently
ended, the quotient of (a) (x) the aggregate EBITDA for such Fiscal Quarter
attributable to such Qualifying Unencumbered Properties for the Fiscal Quarter
most recently ended multiplied by four (4) less (y) $1.50 per square foot of
leased office space within such Qualifying Unencumbered Properties which are
Office Properties, and less (z) in the case of any Qualifying Unencumbered
Property located outside of the United States, an amount equal to the applicable
withholding taxes imposed by any foreign jurisdiction applicable to the EBITDA
attributable to any such Qualifying Unencumbered Property for the applicable
period, divided by (b) 0.0875, plus (ii) for all Qualifying Unencumbered
Properties owned (directly or beneficially) by Borrower, any Financing
Partnership or any Joint Venture Subsidiary which were acquired (directly or
indirectly) by the Borrower, any Financing Partnership or any Joint Venture
Subsidiary during the Fiscal Quarter most recently ended, the aggregate Net
Price of such Qualifying Unencumbered Properties paid by Borrower or its
Affiliates for such Qualifying Unencumbered Properties; provided, however, that,
unless otherwise approved by the Majority Banks, (aa) in the event any such
Qualifying Unencumbered Property is owned by a Joint Venture Subsidiary, the
amount of the EBITDA attributable to such Qualifying Unencumbered Property for
purposes of clause (i) above and the Net Price of such Qualifying Unencumbered
Property for the purposes of clause (ii) above shall be reduced to a percentage
equal to the Borrower's percentage ownership interest (whether direct or
indirect) in such Joint Venture Subsidiary, (bb) the portion of the amount of
the Unencumbered Asset Value attributable to any single Qualifying Unencumbered
Property which would cause such amount to exceed twenty-five percent (25%) of
the total Unencumbered Asset Value at such time (after making all adjustments
required by this proviso) will be disregarded in determining Unencumbered Asset
Value, (cc) the portion of the aggregate amount of the Unencumbered Asset Value
attributable to Qualifying Unencumbered Properties that are Parking Properties
which would cause such aggregate amount to exceed twenty-five percent (25%) of
the total Unencumbered Asset Value at such time (after making all adjustments
required by this proviso) will be


                                       22
<PAGE>   27

disregarded in determining Unencumbered Asset Value, (dd) the portion of the
aggregate amount of the Unencumbered Asset Value attributable to Qualifying
Unencumbered Properties that are Qualifying Unencumbered Properties owned by
Joint Venture Subsidiaries (after first taking into account the adjustment
provided in clause (aa) of this proviso) which would cause such aggregate amount
to exceed thirty-five percent (35%) of the total Unencumbered Asset Value at
such time (after making all adjustments required by this proviso) will be
disregarded in determining Unencumbered Asset Value, and (ee) the portion of the
amount of the Unencumbered Asset Value attributable to all Qualifying
Unencumbered Property located outside of the United States (after first taking
into account the adjustment provided in clause (aa) of this proviso) which would
cause such amount to exceed ten percent (10%) of the total Unencumbered Asset
Value at such time (after making all adjustments required by this proviso) will
be disregarded in determining Unencumbered Asset Value.

    "Unencumbered Net Operating Income" means, for any period, for all
Qualifying Unencumbered Properties, the aggregate EBITDA attributable to each
such Qualifying Unencumbered Property for such period (provided that as to any
Qualifying Unencumbered Property acquired during such period, only EBITDA
attributable to such period occurring after such acquisition shall be included),
as adjusted for a normalized recurring level of capital expenditures by Borrower
for such period, which adjustment shall be at the rate of One Dollar and Fifty
Cents ($1.50) per square foot per annum of office space leased as of the
applicable date of determination for all Qualifying Unencumbered Properties that
are Office Properties (provided that, as to any Office Property acquired during
such period, such amount per square foot shall be pro-rated for the period of
ownership).

    "Unimproved Assets" means Real Property Assets containing no material
improvements.

    "United States" means the United States of America, including the fifty
states and the District of Columbia.

    "Unsecured Debt" means the amount of Indebtedness for borrowed money of EOPT
Borrower and any Financing Partnership which is not Secured Debt, including,
without limitation, the amount of all then outstanding Loans, plus, for the
purpose of calculating the ratio of outstanding Unsecured Debt to Unencumbered
Asset Value, an amount equal to the Borrower's percentage ownership interest
(whether direct or indirect) in each Joint Venture Subsidiary times any
Indebtedness for borrowed money of such Joint Venture Subsidiary which is not
Secured Debt.

    "Unsecured Debt Service" means Debt Service payable in respect of Unsecured
Debt.

    "Unused Commitments" shall mean an amount equal to all unadvanced funds
(other than unadvanced funds in connection with any construction loan) which any
third party is obligated to advance to Borrower or another Person or otherwise
pursuant to any loan document, written instrument or otherwise.

    SECTION 1.2. Accounting Terms and Determinations. Unless otherwise specified
herein, all accounting terms used herein shall be interpreted, all accounting
determinations hereunder shall be made, and all financial statements required to
be delivered hereunder shall be prepared in accordance with GAAP applied on a
basis consistent (except for changes concurred in by the Borrower's independent
public accountants) with the most recent audited consolidated financial
statements of the Borrower and its Consolidated Subsidiaries delivered to the
Administrative Agent; provided that for purposes of references to the financial
results and information of "EOPT, on a consolidated basis," EOPT shall be deemed
to own one hundred percent (100%) of the partnership interests in Borrower; and
provided further that, if the Borrower notifies the Administrative Agent that
the Borrower wishes to amend any covenant in Article V to eliminate the effect
of any change in GAAP on the operation of such covenant (or if the



                                       23
<PAGE>   28

Administrative Agent notifies the Borrower that the Required Banks wish to amend
Article V for such purpose), then the Borrower's compliance with such covenant
shall be determined on the basis of GAAP in effect immediately before the
relevant change in GAAP became effective, until either such notice is withdrawn
or such covenant is amended in a manner reasonably satisfactory to the Borrower
and the Required Banks.

    SECTION 1.3. Types of Borrowings. The term "Borrowing" denotes the
aggregation of Loans of one or more Banks to be made to the Borrower pursuant to
Article 2 on the same date, all of which Loans are of the same type (subject to
Article 8) and, except in the case of Base Rate Loans and Swingline Loans, have
the same initial Interest Period. Borrowings are classified for purposes of this
Agreement either by reference to the pricing of Loans comprising such Borrowing
(e.g., a "Fixed Rate Borrowing" is a Euro-Dollar Borrowing or a Money Market
Borrowing (excluding any such Borrowing consisting of Money Market IBOR Loans
bearing interest at the Base Rate pursuant to Article VIII), and a "Euro-Dollar
Borrowing" is a Borrowing comprised of Euro-Dollar Loans) or by reference to the
provisions of Article 2 under which participation therein is determined (i.e., a
"Committed Borrowing" is a Borrowing under Section 2.1 in which all Banks
participate in proportion to their Commitments, while a "Money Market Borrowing"
is a Borrowing under Section 2.4 in which a Bank's share is determined on the
basis of its bid in accordance therewith, and a "Swingline Borrowing" is a
Borrowing under Section 2.3 in which only the Swingline Lender participates
(subject to the provisions of said Section 2.3)).

    SECTION 1.4. Interrelationship with the Existing Credit Agreement. As stated
in the recitals to this Agreement, this Agreement is intended to amend and
restate the provisions of the Existing Credit Agreement and, notwithstanding the
issuance of the Notes on the Closing Date, (a) all of the terms and provisions
of the Existing Credit Agreement shall continue to apply for the period prior to
the Closing Date, including any determination of the interest periods, payment
dates, interest rates, Events of Default or any amount that may be payable to
the Banks or the Agents, and (b) the "Obligations" under the Existing Credit
Agreement shall continue to be paid or repaid on or prior to the Closing Date in
accordance with the terms thereof, and shall from and after the Closing Date be
paid or repaid in accordance with the terms of this Agreement. All references in
the Loan Documents to the Existing Credit Agreement, as it may be amended from
time to time, shall be deemed to include references to this Agreement. All
"Loans" under the Existing Credit Agreement shall constitute comparable "Loans"
under this Agreement. Borrower hereby acknowledges that no Bank is currently in
default of its obligations under the Existing Credit Agreement.


                                   ARTICLE II

                                   THE CREDITS

    SECTION 2.1. Commitments to Lend. Each Bank severally agrees, on the terms
and conditions set forth in this Agreement, to make Loans to the Borrower
pursuant to this Article from time to time during the term hereof in amounts
such that the aggregate principal amount of Committed Loans by such Bank at any
one time outstanding plus such Bank's Pro Rata Share of Swingline Loans
outstanding at such time shall not exceed the amount of its Commitment. Each
Borrowing outstanding under this Section 2.1 shall be in an aggregate principal
amount of $5,000,000, or an integral multiple of $100,000 in excess thereof
(except that any such Borrowing may be in the aggregate amount available in
accordance with Section 3.2(b)) and, other than with respect to Money Market






                                       24
<PAGE>   29

Loans and Swingline Loans, shall be made from the several Banks ratably in
proportion to their respective Commitments. Subject to the limitations set forth
herein, any amounts repaid may be reborrowed.

    SECTION 2.2. Notice of Borrowing. With respect to any Committed Borrowing,
the Borrower shall give Administrative Agent notice not later than 11:00 a.m.
(Dallas, Texas time) (x) one Business Day before each Base Rate Borrowing, or
(y) three Business Days before each Euro-Dollar Borrowing, specifying:

         (i) the date of such Borrowing, which shall be a Business Day in the
    case of a Base Rate Borrowing or a Business Day in the case of a Euro-Dollar
    Borrowing,

         (ii) the aggregate amount of such Borrowing,

         (iii) whether the Loans comprising such Borrowing are to be Base Rate
    Loans or Euro-Dollar Loans, and

         (iv) in the case of a Euro-Dollar Borrowing, the duration of the
    Interest Period applicable thereto, subject to the provisions of the
    definition of Interest Period.

    SECTION 2.3. Swingline Loan Subfacility.

    (a) Swingline Commitment. Subject to the terms and conditions of this
Section 2.3, the Swingline Lender, in its individual capacity, agrees to make
certain revolving credit loans to the Borrower (each a "Swingline Loan" and,
collectively, the "Swingline Loans") from time to time during the term hereof;
provided, however, that the aggregate amount of Swingline Loans outstanding at
any time shall not exceed the lesser of (i) SEVENTY-FIVE MILLION DOLLARS
($75,000,000), and (ii) the aggregate Commitments less all Loans then
outstanding (the "Swingline Commitment"). Subject to the limitations set forth
herein, any amounts repaid in respect of Swingline Loans may be reborrowed.

    (b)  Swingline Borrowings.

         (i) Notice of Borrowing. With respect to any Swingline Borrowing, the
Borrower shall give the Swingline Lender and the Administrative Agent notice in
writing which is received by the Swingline Lender and Administrative Agent not
later than 1:00 p.m. (Dallas, Texas time) on the proposed date of such Swingline
Borrowing (and confirmed by telephone by such time), specifying (A) that a
Swingline Borrowing is being requested, (B) the amount of such Swingline
Borrowing, (C) the proposed date of such Swingline Borrowing, which shall be a
Business Day and (D) stating that no Default or Event of Default has occurred
and is continuing both before and after giving effect to such Swingline
Borrowing. Such notice shall be irrevocable.

(ii)   Minimum Amounts. Each Swingline Borrowing shall be in a minimum
principal amount of $1,000,000, or an integral multiple of $100,000 in excess
thereof.

         (iii) Repayment of Swingline Loans. Each Swingline Loan shall be due
and payable on the earliest of (A) 5 days from the date of the applicable
Swingline Borrowing, (B) the date of the next Committed Borrowing or (C) the
Maturity Date. If, and to the extent, any Swingline Loans shall be outstanding
on the date of any Committed Borrowing, such Swingline Loans shall first be



                                       25
<PAGE>   30

repaid from the proceeds of such Committed Borrowing prior to the disbursement
of the same to the Borrower. If, and to the extent, a Committed Borrowing is not
requested prior to the Maturity Date or the end of the 5-day period after a
Swingline Borrowing, the Borrower shall be deemed to have requested a Committed
Borrowing comprised entirely of Base Rate Loans in the amount of the applicable
Swingline Loan then outstanding, the proceeds of which shall be used to repay
such Swingline Loan to the Swingline Lender. In addition, the Swingline Lender
may, at any time, in its sole discretion, by written notice to the Borrower and
the Administrative Agent, demand repayment of its Swingline Loans by way of a
Committed Borrowing, in which case the Borrower shall be deemed to have
requested a Committed Borrowing comprised entirely of Base Rate Loans in the
amount of such Swingline Loans then outstanding, the proceeds of which shall be
used to repay such Swingline Loans to the Swingline Lender. Any Committed
Borrowing which is deemed requested by the Borrower in accordance with this
Section 2.3(b)(iii) is hereinafter referred to as a "Mandatory Borrowing". Each
Bank hereby irrevocably agrees to make Committed Loans promptly upon receipt of
notice from the Swingline Lender of any such deemed request for a Mandatory
Borrowing in the amount and in the manner specified in the preceding sentences
and on the date such notice is received by such Bank (or the next Business Day
if such notice is received after 12:00 P.M. (Dallas, Texas time))
notwithstanding (I) the amount of the Mandatory Borrowing may not comply with
the minimum amount of Committed Borrowings otherwise required hereunder, (II)
whether any conditions specified in Section 3.2 are then satisfied, (III)
whether a Default or an Event of Default then exists, (IV) failure of any such
deemed request for a Committed Borrowing to be made by the time otherwise
required in Section 2.1, (V) the date of such Mandatory Borrowing (provided that
such date must be a Business Day), or (VI) any termination of the Commitments
immediately prior to such Mandatory Borrowing or contemporaneously therewith;
provided, however, that no Bank shall be obligated to make Committed Loans in
respect of a Mandatory Borrowing if a Default or an Event of Default then exists
and the applicable Swingline Loan was made by the Swingline Lender without
receipt of a written Notice of Borrowing in the form specified in subclause (i)
above or after Administrative Agent has delivered a notice of Default or Event
of Default which has not been rescinded.

         (iv) Purchase of Participations. In the event that any Mandatory
Borrowing cannot for any reason be made on the date otherwise required above
(including, without limitation, as a result of the commencement of a proceeding
under the Bankruptcy Code with respect to the Borrower), then each Bank hereby
agrees that it shall forthwith purchase (as of the date the Mandatory Borrowing
would otherwise have occurred, but adjusted for any payment received from the
Borrower on or after such date and prior to such purchase) from the Swingline
Lender such participations in the outstanding Swingline Loans as shall be
necessary to cause each such Bank to share in such Swingline Loans ratably based
upon its Pro Rata Share (determined before giving effect to any termination of
the Commitments pursuant to Section 6.2), provided that (A) all interest payable
on the Swingline Loans with respect to any participation shall be for the
account of the Swingline Lender until but excluding the day upon which the
Mandatory Borrowing would otherwise have occurred, and (B) in the event of a
delay between the day upon which the Mandatory Borrowing would otherwise have
occurred and the time any purchase of a participation pursuant to this sentence
is actually made, the purchasing Bank shall be required to pay to the Swingline
Lender interest on the principal amount of such participation for each day from
and including the day upon which the Mandatory Borrowing would otherwise have
occurred to but excluding the date of payment for such participation, at the
rate equal to the Federal Funds Rate, for the two (2) Business Days after the
date the Mandatory





                                       26
<PAGE>   31


Borrowing would otherwise have occurred, and thereafter at a rate equal to the
Base Rate. Notwithstanding the foregoing, no Bank shall be obligated to purchase
a participation in any Swingline Loan if a Default or an Event of Default then
exists and such Swingline Loan was made by the Swingline Lender without receipt
of a written Notice of Borrowing in the form specified in subclause (i) above or
after Administrative Agent has delivered a notice of Default or Event of Default
which has not been rescinded.

    (c) Interest Rate. Each Swingline Loan shall bear interest on the
outstanding principal amount thereof, for each day from the date such Swingline
Loan is made until the date it is repaid, at a rate per annum equal to the
Federal Funds Rate plus the Applicable Margin for Euro-Dollar Loans for such
day.

    SECTION 2.4. Money Market Borrowings.

    (a) The Money Market Option. From time to time during the Term, and provided
that at such time the Borrower maintains a Credit Rating of at least BBB- or
Baa3 (or their equivalent) from two (2) Rating Agencies at least one (1) of
which is S&P or Moody's, the Borrower may, as set forth in this Section 2.4,
request the Banks during the Term to make offers to make Money Market Loans to
the Borrower, not to exceed, at such time, the lesser of (i) $350,000,000
(adjusted pro rata for changes in the aggregate Commitments), and (ii) the
aggregate Commitments less all Loans then outstanding (excluding any Loans or
any portion thereof to be repaid from the proceeds of such Money Market Loans).
Subject to the provisions of this Agreement, the Borrower may repay any
outstanding Money Market Loan on any day which is both a Business Day and a
Business Day and any amounts so repaid may be reborrowed, up to the amount
available under this Section 2.4 at the time of such Borrowing, until the
Business Day next preceding the Maturity Date. The Banks may, but shall have no
obligation to, make such offers and the Borrower may, but shall have no
obligation to, accept any such offers in the manner set forth in this Section
2.4.

    (b) Money Market Quote Request. When the Borrower wishes to request offers
to make Money Market Loans under this Section, it shall transmit to the
Administrative Agent by telex or facsimile transmission a Money Market Quote
Request substantially in the form of Exhibit B hereto (a "Money Market Quote
Request") so as to be received not later than 11:00 A.M. (Dallas, Texas time) on
(x) the fifth Business Day prior to the date of Borrowing proposed therein, in
the case of a IBOR Auction or (y) the Business Day immediately preceding the
date of Borrowing proposed therein, in the case of an Absolute Rate Auction (or,
in either case, such other time or date as the Borrower and the Administrative
Agent shall have mutually agreed and shall have notified the Banks not later
than the date of the Money Market Quote Request for the first IBOR Auction or
Absolute Rate Auction for which such change is to be effective) specifying:

         (i) the proposed date of Borrowing, which shall be a Business Day in
    the case of a IBOR Auction or a Business Day in the case of an Absolute Rate
    Auction,

         (ii) the aggregate amount of such Borrowing, which shall be $5,000,000
    or a larger multiple of $100,000,

         (iii) the duration of the Interest Period applicable thereto (which
    shall not be less than 14 days or more than 180 days), subject to the
    provisions of the definition of Interest Period,


                                       27
<PAGE>   32

         (iv) whether the Money Market Quotes requested are to set forth a Money
    Market Margin or a Money Market Absolute Rate, and

         (v) the aggregate amount of all Money Market Loans then outstanding.

The Borrower may request offers to make Money Market Loans for more than one
Interest Period in a single Money Market Quote Request. In no event may Borrower
give a Money Market Quote Request within ten (10) days of the giving of any
other Money Market Quote Request.

    (c) Invitation for Money Market Quotes. Promptly upon receipt of a Money
Market Quote Request, the Administrative Agent shall send to the Banks by telex
or facsimile transmission an "Invitation for Money Market Quotes" substantially
in the form of Exhibit C hereto, which shall constitute an invitation by the
Borrower to each Bank to submit Money Market Quotes offering to make the Money
Market Loans to which such Money Market Quote Request relates in accordance with
this Section.

    (d) Submission and Contents of Money Market Quotes. 1. Each Bank may submit
a Money Market Quote containing an offer or offers to make Money Market Loans in
response to any Invitation for Money Market Quotes. Each Money Market Quote must
comply with the requirements of this subsection (d) and must be submitted to the
Administrative Agent by telex or facsimile transmission at its offices specified
in or pursuant to Section 9.1 not later than (x) 2:00 P.M. (Dallas, Texas time)
on the fourth Business Day prior to the proposed date of Borrowing, in the case
of a IBOR Auction or (y) 9:30 A.M. (Dallas, Texas time) on the proposed date of
Borrowing, in the case of an Absolute Rate Auction (or, in either case, such
other time or date as the Borrower and the Administrative Agent shall have
mutually agreed and shall have notified to the Banks not later than the date of
the Money Market Quote Request for the first IBOR Auction or Absolute Rate
Auction for which such change is to be effective); provided that Money Market
Quotes submitted by the Administrative Agent (or any affiliate of the
Administrative Agent) in the capacity of a Bank may be submitted, and may only
be submitted, if the Administrative Agent or such affiliate notifies the
Borrower of the terms of the offer or offers contained therein not later than
(x) one hour prior to the deadline for the other Banks, in the case of an IBOR
Auction or (y) one hour prior to the deadline for the other Banks, in the case
of an Absolute Rate Auction. Subject to Articles 3 and 6, any Money Market Quote
so made shall be irrevocable except with the written consent of the
Administrative Agent given on the instructions of the Borrower.

    2. Each Money Market Quote shall be in substantially the form of Exhibit D
hereto and shall in any case specify:

         (i) the proposed date of Borrowing,

         (ii) the principal amount of the Money Market Loan for which each

         such offer is being made, which principal amount (w) may be greater
    than or less than the Commitment of the quoting Bank, (x) must be $5,000,000
    or a larger multiple of $100,000, (y) may not exceed the principal amount of
    Money Market Loans for which offers were requested and (z) may be subject to
    an aggregate limitation as to the principal amount of Money Market Loans for
    which offers being made by such quoting Bank may be accepted,



                                       28
<PAGE>   33

         (iii) the Interest Period(s) with respect to which each such offer is
    being made,

         (iv) in the case of an IBOR Auction, the margin above or below the
    applicable Interbank Offered Rate (the "Money Market Margin") offered for
    each such Money Market Loan, expressed as a percentage (specified to the
    nearest 1/10,000th of 1%) to be added to or subtracted from such base rate,

         (v) in the case of an Absolute Rate Auction, the rate of interest per
    annum (specified to the nearest 1/10,000th of 1%) (the "Money Market
    Absolute Rate") offered for each such Money Market Loan, and

         (vi) the identity of the quoting Bank.

A Money Market Quote may set forth up to five separate offers by the quoting
Bank with respect to each Interest Period specified in the related Invitation
for Money Market Quotes.


    3.   Any Money Market Quote shall be disregarded if it:

         (i) is not substantially in conformity with Exhibit D hereto or does
    not specify all of the information required by subsection (d)(2) above;

         (ii) contains qualifying, conditional or similar language (except for
    an aggregate limitation as provided in subsection (d)(2)(ii) above);

         (iii) proposes terms other than or in addition to those set forth in
    the applicable Invitation for Money Market Quotes; or

         (iv) arrives after the time set forth in subsection (d)(1).

    (e) Notice to Borrower. The Administrative Agent shall promptly (and in any
event within one (1) Business Day after receipt thereof) notify the Borrower in
writing of the terms (x) of any Money Market Quote submitted by a Bank that is
in accordance with subsection (d) and (y) of any Money Market Quote that amends,
modifies or is otherwise inconsistent with a previous Money Market Quote
submitted by such Bank with respect to the same Money Market Quote Request. Any
such subsequent Money Market Quote shall be disregarded by the Administrative
Agent unless such subsequent Money Market Quote is submitted solely to correct a
manifest error in such former Money Market Quote or modifies the terms of such
previous Money Market Quote to provide terms more favorable to Borrower. The
Administrative Agent's notice to the Borrower shall specify (A) the aggregate
principal amount of Money Market Loans for which offers have been received for
each Interest Period specified in the related Money Market Quote Request, (B)
the respective principal amounts and Money Market Margins or Money Market
Absolute Rates, as the case may be, so offered and (C) if applicable,
limitations on the aggregate principal amount of Money Market Loans for which
offers in any single Money Market Quote may be accepted.

    (f) Acceptance and Notice by Borrower. Not later than 10:00 A.M. (Dallas,
Texas time) on (x) the third Business Day prior to the proposed date of
Borrowing, in the case of an IBOR Auction or (y) the proposed date of Borrowing,
in the case of an Absolute Rate Auction (or, in either case, such other time or
date as the Borrower and the Administrative Agent shall have mutually agreed and


                                       29
<PAGE>   34

shall have notified to the Banks not later than the date of the Money Market
Quote Request for the first IBOR Auction or Absolute Rate Auction for which such
change is to be effective), the Borrower shall notify the Administrative Agent
of its acceptance or non-acceptance of the offers so notified to it pursuant to
subsection (e). In the case of acceptance, such notice (a "Notice of Money
Market Borrowing") shall specify the aggregate principal amount of offers for
each Interest Period that are accepted. The Borrower may accept any Money Market
Quote in whole or in part; provided that:

         1. the aggregate principal amount of each Money Market Borrowing may
    not exceed the applicable amount set forth in the related Money Market Quote
    Request;

         2. the principal amount of each Money Market Borrowing must be
    $5,000,000 or a larger multiple of $100,000;

         3. acceptance of offers may only be made on the basis of ascending
    Money Market Margins or Money Market Absolute Rates, as the case may be; and

         4. the Borrower may not accept any offer that is described in
    subsection (d)(3) or that otherwise fails to comply with the requirements of
    this Agreement.

    (g) Allocation by Agent. If offers are made by two or more Banks with the
same Money Market Margins or Money Market Absolute Rates, as the case may be,
for a greater aggregate principal amount than the amount in respect of which
such offers are accepted for the related Interest Period, the principal amount
of Money Market Loans in respect of which such offers are accepted shall be
allocated by the Administrative Agent among such Banks as nearly as possible (in
multiples of $100,000, as the Administrative Agent may deem appropriate) in
proportion to the aggregate principal amounts of such offers. The Administrative
Agent shall promptly (and in any event within one (1) Business Day after such
offers are accepted) notify the Borrower and each such Bank in writing of any
such allocation of Money Market Loans. Determinations by the Administrative
Agent of the allocation of Money Market Loans shall be conclusive in the absence
of manifest error.

    (h) Notwithstanding anything to the contrary contained herein, each Bank
shall be required to fund its Pro Rata Share of Committed Loans in accordance
with Section 2.1 hereof despite the fact that any Bank's Commitment may have
been or may be exceeded as a result of such Bank's making of Money Market Loans.

    SECTION 2.5. Notice to Banks; Funding of Loans.

    (a) Upon receipt of a Notice of Borrowing from Borrower in accordance with
Section 2.2 hereof, the Administrative Agent shall, on the date such Notice of
Borrowing is received by the Administrative Agent, notify Documentation Agent
and each Bank of the contents thereof and of such Bank's share of such
Borrowing, of the interest rate determined pursuant thereto and the Interest
Period(s) (if different from those requested by the Borrower) and such Notice of
Borrowing shall not thereafter be revocable by the Borrower, unless Borrower
shall pay any applicable expenses pursuant to Section 2.13.

    (b) Not later than 1:00 p.m. (Dallas, Texas time) on the date of each
Committed Borrowing (including without limitation each Mandatory Borrowing) as
indicated in the applicable Notice of Borrowing, each Bank shall (except as


                                       30
<PAGE>   35

provided in subsection (d) of this Section) make available its share of such
Committed Borrowing in Federal funds immediately available in Dallas, Texas, to
the Administrative Agent at its address referred to in Section 9.1.

    (c) Not later than 3:00 p.m. (Dallas, Texas time) on the date of each
Swingline Borrowing as indicated in the applicable Notice of Borrowing, the
Swingline Lender shall make available such Swingline Borrowing in Federal funds
immediately available in Dallas, Texas, to the Administrative Agent at its
address referred to in Section 9.1.

    (d) Unless the Administrative Agent shall have received notice from a Bank
prior to the date of any Borrowing that such Bank will not make available to the
Administrative Agent such Bank's share of such Borrowing, the Administrative
Agent may assume that such Bank has made such share available to the
Administrative Agent on the date of such Borrowing in accordance with of this
Section 2.5 and the Administrative Agent may, in reliance upon such assumption,
but shall not be obligated to, make available to the Borrower on such date a
corresponding amount on behalf of such Bank. If and to the extent that such Bank
shall not have so made such share available to the Administrative Agent, such
Bank agrees to repay to the Administrative Agent forthwith on demand such
corresponding amount together with interest thereon, for each day from the date
such amount is made available to the Borrower until the date such amount is
repaid to the Administrative Agent, at the rate of interest applicable to such
Borrowing hereunder. If such Bank shall repay to the Administrative Agent such
corresponding amount, such amount so repaid shall constitute such Bank's Loan
included in such Borrowing for purposes of this Agreement. If such Bank shall
not pay to Administrative Agent such corresponding amount after reasonable
attempts are made by Administrative Agent to collect such amounts from such
Bank, Borrower agrees to repay to Administrative Agent forthwith on demand such
corresponding amounts together with interest thereto, for each day from the date
such amount is made available to Borrower until the date such amount is repaid
to Administrative Agent, at the interest rate applicable thereto one (1)
Business Day after demand. Nothing contained in this Section 2.5(d) shall be
deemed to reduce the Commitment of any Bank or in any way affect the rights of
Borrower with respect to any defaulting Bank or Administrative Agent. The
failure of any Bank to make available to the Administrative Agent such Bank's
share of any Borrowing in accordance with Section 2.5(b) hereof shall not
relieve any other Bank of its obligations to fund its Commitment, in accordance
with the provisions hereof.

    (e) Subject to the provisions hereof, the Administrative Agent shall make
available each Borrowing to Borrower in Federal funds immediately available in
accordance with, and on the date set forth in, the applicable Notice of
Borrowing.

    SECTION 2.6. Notes.

    (a) The Loans of each Bank shall be evidenced by a single Note payable to
the order of such Bank for the account of its Applicable Lending Office.

    (b) Each Bank may, by notice to the Borrower, the Administrative Agent and
the Documentation Agent, request that its Loans of a particular type (including,
without limitation, Swingline Loans and Money Market Loans) be evidenced by a
separate Note in an amount equal to the aggregate unpaid principal amount of
such Loans. Any additional costs incurred by the Administrative Agent, the
Borrower or the Banks in connection with preparing such a Note shall be at the
sole cost and







                                       31
<PAGE>   36


expense of the Bank requesting such Note. In the event any Loans evidenced by
such a Note are paid in full prior to the Maturity Date, any such Bank shall
return such Note to Borrower. Each such Note shall be in substantially the form
of Exhibit A hereto with appropriate modifications to reflect the fact that it
evidences solely Loans of the relevant type. Upon the execution and delivery of
any such Note, any existing Note payable to such Bank shall be replaced or
modified accordingly. Each reference in this Agreement to the "Note" of such
Bank shall be deemed to refer to and include any or all of such Notes, as the
context may require.

    (c) Upon receipt of each Bank's Note pursuant to Section 3.1(a), the
Documentation Agent shall forward such Note to such Bank. Each Bank shall record
the date, amount, type and maturity of each Loan made by it and the date and
amount of each payment of principal made by the Borrower with respect thereto,
and may, if such Bank so elects in connection with any transfer or enforcement
of its Note, endorse on the appropriate schedule appropriate notations to
evidence the foregoing information with respect to each such Loan then
outstanding; provided that the failure of any Bank to make any such recordation
or endorsement shall not affect the obligations of the Borrower hereunder or
under the Notes. Each Bank is hereby irrevocably authorized by the Borrower so
to endorse its Note and to attach to and make a part of its Note a continuation
of any such schedule as and when required.

    (d) The Committed Loans shall mature, and the principal amount thereof shall
be due and payable, on the Maturity Date. The Swingline Loans shall mature, and
the principal amount thereof shall be due and payable, in accordance with
Section 2.3(b)(iii).

    (e) Each Money Market Loan included in any Money Market Borrowing shall
mature, and the principal amount thereof shall be due and payable, together with
accrued interest thereon, on the earlier to occur of (i) last day of the
Interest Period applicable to such Borrowing or (ii) the Maturity Date.

    (f) There shall be no more than ten (10) Euro-Dollar Groups of Loans and no
more than ten (10) Money Market Loans outstanding at any one time.

    SECTION 2.7. Method of Electing Interest Rates. (a) The Loans included in
each Committed Borrowing shall bear interest initially at the type of rate
specified by the Borrower in the applicable Notice of Borrowing or as otherwise
provided in Section 2.3 with respect to Mandatory Borrowings. Thereafter, the
Borrower may from time to time elect to change or continue the type of interest
rate borne by each Group of Loans (subject in each case to the provisions of
Article VIII), as follows:

         (i) if such Loans are Base Rate Loans, the Borrower may elect to
    convert all or any portion of such Loans to Euro-Dollar Loans as of any
    Business Day;

         (ii) if such Loans are Euro-Dollar Loans, the Borrower may elect to
    convert all or any portion of such Loans to Base Rate Loans and/or elect to
    continue all or any portion of such Loans as Euro-Dollar Loans for an
    additional Interest Period or additional Interest Periods, in each case
    effective on the last day of the then current Interest Period applicable to
    such Loans, or on such other date designated by Borrower in the Notice of
    Interest Rate Election provided Borrower shall pay any losses pursuant to
    Section 2.13.



                                       32
<PAGE>   37

Each such election shall be made by delivering a notice (a "Notice of Interest
Rate Election") to the Administrative Agent at least three (3) Business Days
before the conversion or continuation selected in such notice is to be
effective. A Notice of Interest Rate Election may, if it so specifies, apply to
only a portion of the aggregate principal amount of the relevant Group of Loans;
provided that (i) such portion is allocated ratably among the Loans comprising
such Group, (ii) the portion to which such Notice applies, and the remaining
portion to which it does not apply, are each $500,000 or any larger multiple of
$100,000, (iii) there shall be no more than ten (10) Euro-Dollar Groups of Loans
outstanding at any time, (iv) no Committed Loan may be continued as, or
converted into, a Euro-Dollar Loan when any Event of Default has occurred and is
continuing, and (v) no Interest Period shall extend beyond the Maturity Date.

    (b) Each Notice of Interest Rate Election shall specify:

         (i) the Group of Loans (or portion thereof) to which such notice
applies;

         (ii) the date on which the conversion or continuation selected in such
notice is to be effective, which shall comply with the applicable clause of
subsection (a) above;

         (iii) if the Loans comprising such Group are to be converted, the new
type of Loans and, if such new Loans are Euro-Dollar Loans, the duration of the
initial Interest Period applicable thereto; and

         (iv) if such Loans are to be continued as Euro-Dollar Loans for an
additional Interest Period, the duration of such additional Interest Period.

Each Interest Period specified in a Notice of Interest Rate Election shall
comply with the provisions of the definition of Interest Period.

    (c) Upon receipt of a Notice of Interest Rate Election from the Borrower
pursuant to subsection (a) above, the Administrative Agent shall notify the
Documentation Agent and each Bank the same day as it receives such Notice of
Interest Rate Election of the contents thereof, the interest rates determined
pursuant thereto and the Interest Periods (if different from those requested by
the Borrower) and such notice shall not thereafter be revocable by the Borrower.
If the Borrower fails to deliver a timely Notice of Interest Rate Election to
the Administrative Agent for any Group of Euro-Dollar Loans, such Loans shall be
converted into Base Rate Loans on the last day of the then current Interest
Period applicable thereto.

    SECTION 2.8. Interest Rates.

    (a) Each Base Rate Loan shall bear interest on the outstanding principal
amount thereof, for each day from the date such Loan is made until the date it
is repaid or converted into a Euro-Dollar Loan pursuant to Section 2.7, at a
rate per annum equal to the Base Rate plus the Applicable Margin for Base Rate
Loans for such day.

    (b) Each Euro-Dollar Loan shall bear interest on the outstanding principal
amount thereof, for each day during the Interest Period applicable thereto, at a
rate per annum equal to the sum of the Applicable Margin for Euro-Dollar Loans
for such day plus the Adjusted Interbank Offered Rate applicable to such
Interest Period.


                                       33
<PAGE>   38

    (c) Subject to Section 8.1, each Money Market IBOR Loan shall bear interest
on the outstanding principal amount thereof, for the Interest Period applicable
thereto, at a rate per annum equal to the sum of the Interbank Offered Rate for
such Interest Period (determined in accordance with Section 2.8(b) as if the
related Money Market IBOR Borrowing were a Euro-Dollar Borrowing) plus (or
minus) the Money Market Margin quoted by the Bank making such Loan in accordance
with Section 2.4. Each Money Market Absolute Rate Loan shall bear interest on
the outstanding principal amount thereof, for the Interest Period applicable
thereto, at a rate per annum equal to the Money Market Absolute Rate quoted by
the Bank making such Loan in accordance with Section 2.4. Any overdue principal
of or interest on any Money Market Loan shall bear interest, payable on demand,
for each day until paid at a rate per annum equal to the Base Rate until such
failure shall become an Event of Default and thereafter at a rate per annum
equal to the sum of 4% plus the Base Rate for such day.

    (d) In the event that, and for so long as, any Event of Default shall have
occurred and be continuing, the outstanding principal amount of the Loans, and,
to the extent permitted by applicable law, overdue interest in respect of all
Loans, shall bear interest at the annual rate equal to the sum of the Base Rate
and four percent (4%) (the "Default Rate").

    (e) The Administrative Agent shall determine each interest rate applicable
to the Loans hereunder. The Administrative Agent shall give prompt notice to the
Borrower and the Banks of each rate of interest so determined, and its
determination thereof shall be conclusive in the absence of demonstrable error.

    (f)  Intentionally Omitted.

    (g) Interest on all Loans shall be payable on the first Business Day of each
calendar month.

    SECTION 2.9. Fees.

    (a) Facility Fee. For the period beginning on the date hereof and ending on
the date the Obligations are paid in full and this Agreement is terminated (the
"Facility Fee Period"), the Borrower shall pay to the Administrative Agent for
the account of the Banks ratably in proportion to their respective Commitments a
facility fee on the aggregate Commitments at the Applicable Fee Percentage. The
facility fee shall be payable in arrears on each January 1, April 1, July 1 and
October 1 during the Facility Fee Period.

    (b) Agency Fees. Borrower shall pay Administrative Agent, Documentation
Agent and Syndication Agent such fees as are provided for in the agency fee
agreement by and between Administrative Agent and Borrower, as in existence from
time to time.

    (c) Fees Non-Refundable. All fees set forth in this Section 2.9 shall be
deemed to have been earned on the date payment is due in accordance with the
provisions hereof and shall be non-refundable. The obligation of the Borrower to
pay such fees in accordance with the provisions hereof shall be binding upon the
Borrower and shall inure to the benefit of the Administrative Agent, the
Documentation Agent, the Syndication Agent and the Banks regardless of whether
any Loans are actually made.



                                       34
<PAGE>   39

    SECTION 2.10. Maturity Date.

    The term (the "Term") of the Commitments (and each Bank's obligations to
make Loans hereunder) shall terminate and expire on the Maturity Date. Upon the
date of the termination of the Term, any Loans then outstanding (together with
accrued interest thereon and all other Obligations) shall be due and payable on
such date.

    SECTION 2.11. Optional Prepayments.

    (a) The Borrower may, upon at least one (1) Business Day's notice to the
Administrative Agent, prepay any Group of Base Rate Loans or any Money Market
Borrowing bearing interest at the Base Rate pursuant to Section 8.1, in whole at
any time, or from time to time in part in amounts aggregating One Million
Dollars ($1,000,000) or any larger multiple of One Hundred Thousand Dollars
($100,000), by paying the principal amount to be prepaid together with accrued
interest thereon to the date of prepayment. The Borrower may, from time to time
on any Business Day so long as prior notice is given to the Administrative Agent
and Swingline Lender no later than 1:00 p.m. (Dallas, Texas time) on the day on
which Borrower intends to make such prepayment, prepay any Swingline Loans in
whole or in part in amounts aggregating $100,000 or a higher integral multiple
of $100,000 (or, if less, the aggregate outstanding principal amount of all
Swingline Loans then outstanding) by paying the principal amount to be prepaid
together with accrued interest thereon to the date of prepayment no later than
2:00 p.m. (Dallas, Texas time) on such day. Each such optional prepayment shall
be applied to prepay ratably the Loans of the several Banks (or the Swingline
Lender in the case of Swingline Loans) included in such Group or Borrowing.

    (b) The Borrower may, upon at least one (1) Business Days' notice to the
Administrative Agent, prepay any Euro-Dollar Loan as of the last day of the
Interest Period applicable thereto. Except as provided in Article 8 and except
with respect to any Euro-Dollar Loan which has been converted to a Base Rate
Loan pursuant to Section 8.2, 8.3 or 8.4 hereof, the Borrower may not prepay all
or any portion of the principal amount of any Euro-Dollar Loan prior to the end
of the Interest Period applicable thereto unless the Borrower shall also pay any
applicable expenses pursuant to Section 2.13. In addition, the Borrower may not
prepay all or any portion of the principal amount of any Money Market Loan prior
to the end of the Interest Period applicable thereto without the consent of all
applicable Designated Lenders and Banks. Any such prepayment shall be upon at
least three (3) Business Days notice to the Administrative Agent. Each such
optional prepayment shall be in the amounts set forth in Section 2.11(a) above
and shall be applied to prepay ratably the Loans of the Banks included in any
Group of Euro-Dollar Loans, except that any Euro-Dollar Loan which has been
converted to a Base Rate Loan pursuant to Section 8.2, 8.3 or 8.4 hereof may be
prepaid without ratable payment of the other Loans in such Group of Loans which
have not been so converted.

    (c) The Borrower may at any time and from time to time cancel all or any
part of the Commitments by the delivery to the Administrative Agent of a notice
of cancellation within the applicable time periods set forth in Sections 2.11(a)
and (b) if there are Loans then outstanding or, if there are no Loans
outstanding at such time as to which the Commitments with respect thereto are
being canceled, upon at least one (1) Business Day's notice to the
Administrative Agent, whereupon, in either event, all or such portion of the
Commitments, as applicable, shall terminate as to the Banks, pro rata on the
date set forth in such notice of cancellation, and, if there are any Loans then
outstanding, Borrower shall prepay, as applicable, all or such portion of Loans



                                       35
<PAGE>   40

outstanding on such date in accordance with the requirements of Section 2.11(a)
and (b), Borrower shall be permitted to designate in its notice of cancellation
which Loans, if any, are to be prepaid. A reduction of the Commitments pursuant
to this Section 2.11(c) shall not effect a reduction in the Swingline Commitment
(unless so elected by the Borrower) until the aggregate Commitments have been
reduced to an amount equal to the Swingline Commitment.

    (d) Any amounts so prepaid pursuant to Section 2.11 (a) or (b) may be
reborrowed. In the event Borrower elects to cancel all or any portion of the
Commitments and the Swingline Commitment pursuant to Section 2.11(c) hereof,
such amounts may not be reborrowed.

    SECTION 2.12. General Provisions as to Payments.

    (a) The Borrower shall make each payment of principal of and interest on the
Loans and of fees hereunder, not later than 11:00 a.m. (Dallas, Texas time) on
the date when due, in Federal or other funds immediately available in Dallas,
Texas, to the Administrative Agent at its address referred to in Section 9.1.
The Administrative Agent will promptly (and in any event within one (1) Business
Day after receipt thereof) distribute to each Bank its ratable share (or
applicable share with respect to Money Market Loans) of each such payment
received by the Administrative Agent for the account of the Banks. If and to the
extent that the Administrative Agent shall receive any such payment for the
account of the Banks on or before 12:00 Noon (Dallas, Texas time) on any
Business Day, and Administrative Agent shall not have distributed to any Bank
its applicable share of such payment on such Business Day, Administrative Agent
shall distribute such amount to such Bank together with interest thereon, for
each day from the date such amount should have been distributed to such Bank
until the date Administrative Agent distributes such amount to such Bank, at the
Federal Funds Rate. Whenever any payment of principal of, or interest on the
Base Rate Loans or Swingline Loans or of fees shall be due on a day which is not
a Business Day, the date for payment thereof shall be extended to the next
succeeding Business Day. Whenever any payment of principal of, or interest on,
the Euro-Dollar Loans shall be due on a day which is not a Business Day, the
date for payment thereof shall be extended to the next succeeding Business Day
unless such Business Day falls in another calendar month, in which case the date
for payment thereof shall be the next preceding Business Day. Whenever any
payment of principal of, or interest on, the Money Market Loans shall be due on
a day which is not a Business Day, the date for payment thereof shall be
extended to the next succeeding Business Day. If the date for any payment of
principal is extended by operation of law or otherwise, interest thereon shall
be payable for such extended time.

    (b) Unless the Administrative Agent shall have received notice from the
Borrower prior to the date on which any payment is due to the Banks hereunder
that the Borrower will not make such payment in full, the Administrative Agent
may assume that the Borrower has made such payment in full to the Administrative
Agent on such date and the Administrative Agent may, in reliance upon such
assumption, cause to be distributed to each Bank on such due date an amount
equal to the amount then due such Bank. If and to the extent that the Borrower
shall not have so made such payment, each Bank shall repay to the Administrative
Agent forthwith on demand such amount distributed to such Bank together with
interest thereon, for each day from the date such amount is distributed to such
Bank until the date such Bank repays such amount to the Administrative Agent, at
the Federal Funds Rate.



                                       36
<PAGE>   41

    SECTION 2.13. Funding Losses. If the Borrower makes any payment of principal
with respect to any Euro-Dollar Loan or Money Market IBOR Loan (pursuant to
Article II, VI or VIII or otherwise) on any day other than the last day of the
Interest Period applicable thereto, or if the Borrower fails to borrow any
Euro-Dollar Loans or Money Market IBOR Loans after notice has been given to any
Bank in accordance with Section 2.5(a) or 2.4(f), as applicable, or if Borrower
shall deliver a Notice of Interest Rate Election specifying that a Euro-Dollar
Loan shall be converted on a date other than the first (1st) day of the then
current Interest Period applicable thereto, the Borrower shall reimburse each
Bank within 15 days after certification of such Bank of such loss or expense
(which shall be delivered by each such Bank to Administrative Agent for delivery
to Borrower) for any resulting loss or expense incurred by it (or by an existing
Participant in the related Loan), including, without limitation, any loss
incurred in obtaining, liquidating or employing deposits from third parties, but
excluding loss of margin for the period after any such payment or failure to
borrow, provided that such Bank shall have delivered to Administrative Agent and
Administrative Agent shall have delivered to the Borrower a certification as to
the amount of such loss or expense, which certification shall set forth in
reasonable detail the basis for and calculation of such loss or expense and
shall be conclusive in the absence of demonstrable error.

    SECTION 2.14. Computation of Interest and Fees. All interest and fees shall
be computed on the basis of a year of 360 days and paid for the actual number of
days elapsed (including the first day but excluding the last day).

    SECTION 2.15. Use of Proceeds. The Borrower shall use the proceeds of the
Loans for general corporate purposes, including, without limitation, the
acquisition of real property to be used in the Borrower's existing business and
for general working capital needs of the Borrower; provided, however, that no
Swingline Loan shall be used more than once for the purpose of refinancing
another Swingline Loan, in whole or part.

                                   ARTICLE III

                                   CONDITIONS

    SECTION 3.1. Closing. The closing hereunder shall occur on the date when
each of the following conditions is satisfied (or waived in writing by the
Administrative Agent and the Banks), each document to be dated the Closing Date
unless otherwise indicated:

    (a) the Borrower shall have executed and delivered to the Documentation
Agent a Note for the account of each Bank dated on or before the Closing Date
complying with the provisions of Section 2.6;

    (b) the Borrower, the Administrative Agent and Documentation Agent and each
of the Banks shall have executed and delivered to the Borrower, the
Administrative Agent and Documentation Agent a duly executed original of this
Agreement;

    (c) EOPT shall have executed and delivered to the Administrative Agent and
Documentation Agent a duly executed original of the EOPT Guaranty;

    (d)  the Documentation Agent shall have received an opinion of Rosenberg &
Liebentritt, P.C., counsel for the Borrower and EOPT, acceptable to the
Documentation Agent, the Banks and their counsel;



                                       37
<PAGE>   42

    (e) the Documentation Agent shall have received all documents the
Documentation Agent may reasonably request relating to the existence of the
Borrower and EOPT, the authority for and the validity of this Agreement and the
other Loan Documents, the incumbency of officers executing this Agreement and
the other Loan Documents and any other matters relevant hereto, all in form and
substance satisfactory to the Administrative Agent. Such documentation shall
include, without limitation, the agreement of limited partnership of the
Borrower, as well as the certificate of limited partnership of the Borrower,
both as amended, modified or supplemented to the Closing Date, certified to be
true, correct and complete by a senior officer of the Borrower as of a date not
more than ten (10) days prior to the Closing Date, together with a certificate
of existence as to the Borrower from the Secretary of State (or the equivalent
thereof) of Delaware, to be dated not more than thirty (30) days prior to the
Closing Date, as well as the declaration of trust of EOPT, as amended, modified
or supplemented to the Closing Date, certified to be true, correct and complete
by a senior officer of EOPT as of a date not more than ten (10) days prior to
the Closing Date, together with a good standing certificate as to EOPT from the
Secretary of State (or the equivalent thereof) of Maryland, to be dated not more
than thirty (30) days prior to the Closing Date;

    (f)  the Borrower and EOPT each shall have executed a solvency certificate
acceptable to the Documentation Agent;

    (g) the Documentation Agent shall have received all certificates, agreements
and other documents and papers referred to in this Section 3.1 and the Notice of
Borrowing referred to in Section 3.2, if applicable, unless otherwise specified,
in sufficient counterparts, satisfactory in form and substance to the
Documentation Agent in their sole discretion;

    (h) the Borrower shall have taken all actions required to authorize the
execution and delivery of this Agreement and the other Loan Documents and the
performance thereof by the Borrower, and EOPT shall have taken all actions
required to authorize the execution and delivery of the reaffirmation of the
EOPT Guaranty and the other Loan Documents and the performance thereof by EOPT;

    (i) the Banks shall be satisfied that neither the Borrower, EOPT nor any
Consolidated Subsidiary is subject to any present or contingent environmental
liability which could have a Material Adverse Effect and the Borrower shall have
delivered a certificate so stating;

    (j) the Administrative Agent shall have received, for its and any other
Bank's account, all fees due and payable pursuant to Section 2.9 hereof on or
before the Closing Date, and the reasonable fees and expenses accrued through
the Closing Date of Skadden, Arps, Slate, Meagher & Flom LLP shall have been
paid to Skadden, Arps, Slate, Meagher & Flom LLP;

    (k) the Borrower shall have delivered copies of all consents, licenses and
approvals, if any, required in connection with the execution, delivery and
performance by the Borrower and EOPT, and the validity and enforceability, of
the Loan Documents, or in connection with any of the transactions contemplated
thereby, and such consents, licenses and approvals shall be in full force and
effect;

    (l)  no Default or Event of Default shall have occurred;



                                       38
<PAGE>   43

    (m) the Borrower shall have delivered a certificate in form acceptable to
Documentation Agent showing compliance with the requirements of Section 5.8 as
of the Closing Date; and

    (n) the Borrower shall have repaid in full all amounts outstanding under the
Term Loan Agreement, and terminated the same.

    SECTION 3.2. Borrowings. The obligation of any Bank to make a Loan is
subject to the satisfaction of the following conditions:

    (a) receipt by the Administrative Agent of a Notice of Borrowing as required
by Section 2.2 or Section 2.3(b)(i) or a Notice of Money Market Borrowing as
required by Section 2.4;

    (b) immediately after such Borrowing, the aggregate outstanding principal
amount of the Loans will not exceed the aggregate amount of the Commitments;

    (c) immediately before and after such Borrowing, no Default or Event of
Default shall have occurred and be continuing both before and after giving
effect to the making of such Loans;

    (d) the representations and warranties of the Borrower contained in this
Agreement (other than representations and warranties which expressly speak as of
a different date) shall be true and correct in all material respects on and as
of the date of such Borrowing both before and after giving effect to the making
of such Loans;

    (e) no law or regulation shall have been adopted, no order, judgment or
decree of any governmental authority shall have been issued, and no litigation
shall be pending, which does or seeks to enjoin, prohibit or restrain, the
making or repayment of the Loans or the consummation of the transactions
contemplated by this Agreement; and

    (f) no event, act or condition shall have occurred after the Closing Date
which, in the reasonable judgment of the Administrative Agent, Documentation
Agent or the Required Banks, as the case may be, has had or is likely to have a
Material Adverse Effect.

Each Borrowing hereunder shall be deemed to be a representation and warranty by
the Borrower on the date of such Borrowing as to the facts specified in clauses
(b), (c), (d), (e) and (f) (to the extent that Borrower is or should have been
aware of any Material Adverse Effect) of this Section, except as otherwise
disclosed in writing by Borrower to the Banks. Notwithstanding anything to the
contrary, no Borrowing shall be permitted if such Borrowing would cause Borrower
to fail to be in compliance with any of the covenants contained in this
Agreement or in any of the other Loan Documents.


                                   ARTICLE IV

                         REPRESENTATIONS AND WARRANTIES

    In order to induce the Administrative Agent, Documentation Agent and each of
the other Banks which is or may become a party to this Agreement to make the
Loans, the Borrower makes the following representations and warranties as of the



                                       39
<PAGE>   44

Closing Date. Such representations and warranties shall survive the
effectiveness of this Agreement, the execution and delivery of the other Loan
Documents and the making of the Loans.

    SECTION 4.1. Existence and Power. The Borrower is a limited partnership,
duly formed and validly existing as a limited partnership under the laws of the
State of Delaware and has all powers and all material governmental licenses,
authorizations, consents and approvals required to own its property and assets
and carry on its business as now conducted or as it presently proposes to
conduct and has been duly qualified and is in good standing in every
jurisdiction in which the failure to be so qualified and/or in good standing is
likely to have a Material Adverse Effect. EOPT is a real estate investment
trust, duly formed, validly existing and in good standing as a real estate
investment trust under the laws of the State of Maryland and has all powers and
all material governmental licenses, authorizations, consents and approvals
required to own its property and assets and carry on its business as now
conducted or as it presently proposes to conduct and has been duly qualified and
is in good standing in every jurisdiction in which the failure to be so
qualified and/or in good standing is likely to have a Material Adverse Effect.

    SECTION 4.2. Power and Authority. The Borrower has the partnership power and
authority to execute, deliver and carry out the terms and provisions of each of
the Loan Documents to which it is a party and has taken all necessary
partnership action, if any, to authorize the execution and delivery on behalf of
the Borrower and the performance by the Borrower of such Loan Documents. The
Borrower and EOPT each have duly executed and delivered each Loan Document to
which it is a party in accordance with the terms of this Agreement, and each
such Loan Document constitutes the legal, valid and binding obligation of the
Borrower and EOPT, enforceable in accordance with its terms, except as
enforceability may be limited by applicable insolvency, bankruptcy or other laws
affecting creditors rights generally, or general principles of equity, whether
such enforceability is considered in a proceeding in equity or at law. EOPT has
the power and authority to execute, deliver and carry out the terms and
provisions of each of the Loan Documents to which it is a party and has taken
all necessary action to authorize the execution, delivery and performance of
such Loan Documents. EOPT has the power and authority to execute, deliver and
carry out the terms and provisions of each of the Loan Documents on behalf of
the Borrower to which the Borrower is a party and has taken all necessary action
to authorize the execution and delivery on behalf of the Borrower and the
performance by the Borrower of such Loan Documents.

    SECTION 4.3. No Violation. (a) Neither the execution, delivery or
performance by or on behalf of the Borrower of the Loan Documents to which it is
a party, nor compliance by the Borrower with the terms and provisions thereof
nor the consummation of the transactions contemplated by the Loan Documents, (i)
will materially contravene any applicable provision of any law, statute, rule,
regulation, order, writ, injunction or decree of any court or governmental
instrumentality, (ii) will materially conflict with or result in any breach of,
any of the terms, covenants, conditions or provisions of, or constitute a
default under, or result in the creation or imposition of (or the obligation to
create or impose) any Lien upon any of the property or assets of the Borrower or
any of its Consolidated Subsidiaries pursuant to the terms of any indenture,
mortgage, deed of trust, or other agreement or other instrument to which the
Borrower (or of any partnership of which the Borrower is a partner) or any of
its Consolidated Subsidiaries is a party or by which it or any of its property
or assets is bound or to which it is subject (except for such breaches and



                                       40
<PAGE>   45

defaults under loan agreements which the lenders thereunder have agreed to
forbear pursuant to valid forbearance agreements), or (iii) will cause a
material default by the Borrower under any organizational document of any Person
in which the Borrower has an interest, or cause a material default under the
Borrower's agreement or certificate of limited partnership, the consequences of
which conflict, breach or default would have a Material Adverse Effect, or
result in or require the creation or imposition of any Lien whatsoever upon any
Property (except as contemplated herein).

    (b) Neither the execution, delivery or performance by EOPT of the Loan
Documents to which it is a party, nor compliance by EOPT with the terms and
provisions thereof nor the consummation of the transactions contemplated by the
Loan Documents, (i) will materially contravene any applicable provision of any
law, statute, rule, regulation, order, writ, injunction or decree of any court
or governmental instrumentality, (ii) will materially conflict with or result in
any breach of, any of the terms, covenants, conditions or provisions of, or
constitute a default under, or result in the creation or imposition of (or the
obligation to create or impose) any Lien upon any of the property or assets of
EOPT or any of its Consolidated Subsidiaries pursuant to the terms of any
indenture, mortgage, deed of trust, or other agreement or other instrument to
which EOPT (or of any partnership of which EOPT is a partner) or any of its
Consolidated Subsidiaries is a party or by which it or any of its property or
assets is bound or to which it is subject (except for such breaches and defaults
under loan agreements which the lenders thereunder have agreed to forbear
pursuant to valid forbearance agreements), or (iii) will cause a material
default by EOPT under any organizational document of any Person in which EOPT
has an interest, the consequences of which conflict, breach or default would
have a Material Adverse Effect, or result in or require the creation or
imposition of any Lien whatsoever upon any Property (except as contemplated
herein).

    SECTION 4.4. Financial Information. (a) The consolidated balance sheet of
EOPT as of December 31, 1997, and the related statements of operations and cash
flows of EOPT for the period from July 11, 1997 to December 31, 1997, reported
on by Ernst & Young LLP, fairly present, in conformity with GAAP, the
consolidated financial position of EOPT as of such date and the consolidated
results of operations and cash flows for the period from July 11, 1997 to
December 31, 1997.

    (b) Since March 31, 1998, (i) except as may have been disclosed in writing
to the Banks, nothing has occurred having a Material Adverse Effect, and (ii)
except as set forth on Schedule 4.4(b), neither the Borrower nor EOPT has
incurred any material indebtedness or guaranty on or before the Closing Date.

    SECTION 4.5. Litigation. Except as previously disclosed by the Borrower in
writing to the Banks, there is no action, suit or proceeding pending against, or
to the knowledge of the Borrower threatened against or affecting, (i) the
Borrower, EOPT or any of their Consolidated Subsidiaries, (ii) the Loan
Documents or any of the transactions contemplated by the Loan Documents or (iii)
any of their assets, before any court or arbitrator or any governmental body,
agency or official in which there is a reasonable possibility of an adverse
decision which could, individually, or in the aggregate have a Material Adverse
Effect or which in any manner draws into question the validity of this Agreement
or the other Loan Documents. As of the Closing Date, no such action, suit or
proceeding exists.



                                       41
<PAGE>   46

    SECTION 4.6. Compliance with ERISA. (a) Except as set forth on Schedule 4.6
attached hereto, neither Borrower nor EOPT is a member of or has entered into,
maintained, contributed to, or been required to contribute to, or may incur any
liability with respect to any Plan or Multiemployer Plan or any other Benefit
Arrangement.

    (b) Except for a "prohibited transaction" arising solely because of a Bank's
breach of the covenant set forth in Section 9.17 hereof, the transactions
contemplated by the Loan Documents will not constitute a nonexempt prohibited
transaction (as such term is defined in Section 4975 of the Code or Section 406
of ERISA) that could subject the Administrative Agent, Documentation Agent or
any of the Banks to any tax or penalty on prohibited transactions imposed under
Section 4975 of the Code or Section 502(i) of ERISA and such transactions will
not otherwise result in the Administrative Agent, the Documentation Agent or any
of the Banks being deemed in violation of Sections 404 or 406 of ERISA or
Section 4975 of the Code or in the Administrative Agent, the Documentation Agent
or any of the Banks being a fiduciary or party in interest under ERISA or a
"disqualified person" as defined in Section 4975(e)(2) of the Code with respect
to an "employee benefit plan" within the meaning of Section 3(3) of ERISA or a
"plan" within the meaning of Section 4975(e)(1) of the Code. No assets of
Borrower constitute "assets" (within the meaning of ERISA or Section 4975 of the
Code, including, but not limited to, 29 C.F.R. Section 2510.3-101 or any
successor regulation thereto) of an "employee benefit plan" within the meaning
of Section 3(3) of ERISA or a "plan" within the meaning of Section 4975(e)(1) of
the Code. In addition to the prohibitions set forth in this Agreement and the
other Loan Documents, and not in limitation thereof, Borrower covenants and
agrees that Borrower shall not use any "assets" (within the meaning of ERISA or
Section 4975 of the Code, including but not limited to 29 C.F.R. Section
2510.3-101) of an "employee benefit plan" within the meaning of Section 3(3) of
ERISA or a "plan" within the meaning of Section 4975(e)(1) of the Code to repay
or secure the Note, the Loan, or the Obligations.

    SECTION 4.7. Environmental. The Borrower conducts reviews of the effect of
Environmental Laws on the business, operations and properties of the Borrower
and its Consolidated Subsidiaries when necessary in the course of which it
identifies and evaluates associated liabilities and costs (including, without
limitation, any capital or operating expenditures required for clean-up or
closure of properties presently owned, any capital or operating expenditures
required to achieve or maintain compliance with environmental protection
standards imposed by law or as a condition of any license, permit or contract,
any related constraints on operating activities, and any actual or potential
liabilities to third parties, including, without limitation, employees, and any
related costs and expenses). On the basis of this review, the Borrower has
reasonably concluded that such associated liabilities and costs, including,
without limitation, the costs of compliance with Environmental Laws, are
unlikely to have a Material Adverse Effect.

    SECTION 4.8. Taxes. The Borrower, EOPT and their Consolidated Subsidiaries
have filed all United States Federal income tax returns and all other material
tax returns which are required to be filed by them and have paid all taxes due
pursuant to such returns or pursuant to any assessment received by the Borrower,
EOPT or any Consolidated Subsidiary, except such taxes, if any, as are reserved
against in accordance with GAAP, such taxes as are being contested in good faith
by appropriate proceedings or such taxes, the failure to make payment of which
when due and payable will not have, in the aggregate, a Material Adverse Effect.
The charges, accruals and reserves on the books of the Borrower, EOPT and their
Consolidated Subsidiaries in respect of taxes or other governmental charges are,
in the opinion of the Borrower, adequate.

                                       42
<PAGE>   47

    SECTION 4.9. Full Disclosure. All information heretofore furnished by the
Borrower to the Administrative Agent, Documentation Agent or any Bank for
purposes of or in connection with this Agreement or any transaction contemplated
hereby or thereby is true and accurate in all material respects on the date as
of which such information is stated or certified. The Borrower has disclosed to
the Documentation Agent, in writing any and all facts which have or may have (to
the extent the Borrower can now reasonably foresee) a Material Adverse Effect.

    SECTION 4.10. Solvency. On the Closing Date and after giving effect to the
transactions contemplated by the Loan Documents occurring on the Closing Date,
the Borrower and EOPT will be Solvent.

    SECTION 4.11. Use of Proceeds. All proceeds of the Loans will be used by the
Borrower only in accordance with the provisions hereof. Neither the making of
any Loan nor the use of the proceeds thereof will violate or be inconsistent
with the provisions of regulations T, U, or X of the Federal Reserve Board.

    SECTION 4.12. Governmental Approvals. No order, consent, approval, license,
authorization, or validation of, or filing, recording or registration with, or
exemption by, any governmental or public body or authority, or any subdivision
thereof, is required to authorize, or is required in connection with the
execution, delivery and performance of any Loan Document or the consummation of
any of the transactions contemplated thereby other than those that have already
been duly made or obtained and remain in full force and effect or those which,
if not made or obtained, would not have a Material Adverse Effect;

    SECTION 4.13. Investment Company Act; Public Utility Holding Company Act.
Neither the Borrower, EOPT nor any Consolidated Subsidiary is (x) an "investment
company" or a company "controlled" by an "investment company", within the
meaning of the Investment Company Act of 1940, as amended, (y) a "holding
company" or a "subsidiary company" of a "holding company" or an "affiliate" of
either a "holding company" or a "subsidiary company" within the meaning of the
Public Utility Holding Company Act of 1935, as amended, or (z) subject to any
other federal or state law or regulation which purports to restrict or regulate
its ability to borrow money.

    SECTION 4.14. Principal Offices. As of the Closing Date, the principal
office, chief executive office and principal place of business of the Borrower
is Two North Riverside Plaza, Suite 2200, Chicago, Illinois 60606.

    SECTION 4.15. REIT Status. EOPT is qualified and EOPT intends to continue to
qualify as a real estate investment trust under the Code.

    SECTION 4.16. Patents, Trademarks, etc. The Borrower has obtained and holds
in full force and effect all patents, trademarks, servicemarks, trade names,
copyrights and other such rights, free from burdensome restrictions, which are
necessary for the operation of its business as presently conducted, the
impairment of which is likely to have a Material Adverse Effect.

    SECTION 4.17. Judgments. As of the Closing Date, there are no final,
non-appealable judgments or decrees in an aggregate amount of Five Million
Dollars ($5,000,000) or more entered by a court or courts of competent
jurisdiction against EOPT or the Borrower or, to the extent such judgment would



                                       43
<PAGE>   48

be recourse to EOPT or Borrower, any of its Consolidated Subsidiaries (other
than judgments as to which, and only to the extent, a reputable insurance
company has acknowledged coverage of such claim in writing).

    SECTION 4.18. No Default. No Event of Default or, to the best of the
Borrower's knowledge, Default exists under or with respect to any Loan Document
and the Borrower is not in default in any material respect beyond any applicable
grace period under or with respect to any other material agreement, instrument
or undertaking to which it is a party or by which it or any of its property is
bound in any respect, the existence of which default is likely to result in a
Material Adverse Effect.

    SECTION 4.19. Licenses, etc. The Borrower has obtained and does hold in full
force and effect, all franchises, licenses, permits, certificates,
authorizations, qualifications, accreditation, easements, rights of way and
other consents and approvals which are necessary for the operation of its
businesses as presently conducted, the absence of which is likely to have a
Material Adverse Effect.

    SECTION 4.20. Compliance With Law. To the Borrower's knowledge, the Borrower
and each of its Real Property Assets are in compliance with all laws, rules,
regulations, orders, judgments, writs and decrees, including, without
limitation, all building and zoning ordinances and codes, the failure to comply
with which is likely to have a Material Adverse Effect.

    SECTION 4.21. No Burdensome Restrictions. Except as may have been disclosed
by the Borrower in writing to the Banks, Borrower is not a party to any
agreement or instrument or subject to any other obligation or any charter or
corporate or partnership restriction, as the case may be, which, individually or
in the aggregate, is likely to have a Material Adverse Effect.

    SECTION 4.22. Brokers' Fees. The Borrower has not dealt with any broker or
finder with respect to the transactions contemplated by this Agreement or
otherwise in connection with this Agreement, and the Borrower has not done any
act, had any negotiations or conversation, or made any agreements or promises
which will in any way create or give rise to any obligation or liability for the
payment by the Borrower of any brokerage fee, charge, commission or other
compensation to any party with respect to the transactions contemplated by the
Loan Documents, other than the fees payable to the Administrative Agent, the
Documentation Agent, the Syndication Agent and the Banks, and certain other
Persons as previously disclosed in writing to the Administrative Agent.

    SECTION 4.23. Labor Matters. Except as disclosed on Schedule 4.6, there are
no collective bargaining agreements or Multiemployer Plans covering the
employees of the Borrower or any member of the ERISA Group and neither the
Borrower nor any member of the ERISA Group has suffered any strikes, walkouts,
work stoppages or other material labor difficulty within the last five years.

    SECTION 4.24. Insurance. The Borrower currently maintains insurance at 100%
replacement cost insurance coverage (subject to customary deductibles) in
respect of each of its Real Property Assets, as well as commercial general
liability insurance (including, without limitation, "builders' risk" where
applicable) against claims for personal, and bodily injury and/or death, to one
or more persons, or property damage, as well as workers' compensation insurance,
in each case with respect to liability and casualty insurance with insurers
having an A.M. Best policyholders' rating of not less than A-VII in amounts that
prudent owners of assets such as Borrower's directly or indirectly owned Real
Property Assets would maintain.



                                       44
<PAGE>   49

    SECTION 4.25. Organizational Documents. The documents delivered pursuant to
Section 3.1(e) constitute, as of the Closing Date, all of the organizational
documents (together with all amendments and modifications thereof) of the
Borrower and EOPT. The Borrower represents that it has delivered to the
Documentation Agent true, correct and complete copies of each such documents.
Schedule 4.25 attached hereto is a true and correct summary of the partners of
the Borrower as of the date hereof and the interest in the Borrower held by each
such partner as of the date hereof. EOPT is the managing general partner of the
Borrower and each of Zell/Merrill Lynch Real Estate Opportunity Partners Limited
Partnership, Zell/Merrill Lynch Real Estate Opportunity Partners Limited
Partnership II, Zell/Merrill Lynch Real Estate Opportunity Partners Limited
Partnership III, and Zell/Merrill Lynch Real Estate Opportunity Partners Limited
Partnership IV as of the date hereof. EOPT holds (directly or indirectly) a
89.70% ownership interest in the Borrower as of the date hereof.

    SECTION 4.26. Qualifying Unencumbered Properties. As of the date hereof,
each Property listed on Schedule 1.1 as a Qualifying Unencumbered Property (i)
is an operating Office Building or Parking Property wholly-owned (directly or
beneficially) by Borrower, a Financing Partnership or a Joint Venture
Subsidiary, (ii) is not subject (nor are any equity interests in such Property
that are owned directly or indirectly by Borrower, EOPT or any Joint Venture
Parent subject) to a Lien which secures Indebtedness of any Person, other than
Permitted Liens, and (iii) is not subject (nor are any equity interests in such
Property that are owned directly or indirectly by Borrower, EOPT or Joint
Venture Parent subject) to any covenant, condition, or other restriction which
prohibits or limits the creation or assumption of any Lien upon such Property.
All of the information set forth on Schedule 1.1 is true and correct in all
material respects.

    SECTION 4.27. "Year 2000" Compliance. The Borrower and EOPT have conducted a
review and assessment of the Borrower's and EOPT's computer applications with
respect to the "year 2000 problem" (that is, the risk that computer applications
may not be able to properly perform date-sensitive functions after December 31,
1999) and, based on that review and inquiry, the Borrower does not believe that
year 2000 problem will result in a Material Adverse Effect to the Borrower's or
EOPT's financial condition or results of operations, or on its ability to repay
the Loan.


                                    ARTICLE V

                       AFFIRMATIVE AND NEGATIVE COVENANTS

    The Borrower covenants and agrees that, so long as any Bank has any
Commitment hereunder or any Obligations remain unpaid:

    SECTION 5.1. Information. The Borrower will deliver to each of the Banks:

    (a) as soon as available and in any event within five (5) Business Days
after the same is required to be filed with the Securities and Exchange
Commission (but in no event later than 125 days after the end of each Fiscal
Year of the Borrower) a consolidated balance sheet of the Borrower, EOPT and
their Consolidated Subsidiaries as of the end of such Fiscal Year and the
related consolidated statements of Borrower's and EOPT's operations and



                                       45
<PAGE>   50

consolidated statements of Borrower's and EOPT's cash flow for such Fiscal Year,
setting forth in each case in comparative form the figures for the previous
Fiscal Year (if available), all reported in a manner acceptable to the
Securities and Exchange Commission on Borrower's and EOPT's Form 10K and
reported on by Ernst & Young LLP or other independent public accountants of
nationally recognized standing;

    (b) as soon as available and in any event within five (5) Business Days
after the same is required to be filed with the Securities and Exchange
Commission (but in no event later than 80 days after the end of each of the
first three quarters of each Fiscal Year of the Borrower and EOPT), (i) a
consolidated balance sheet of the Borrower, EOPT and their Consolidated
Subsidiaries as of the end of such quarter and the related consolidated
statements of Borrower's and EOPT's operations and consolidated statements of
Borrower's and EOPT's cash flow for such quarter and for the portion of the
Borrower's or EOPT's Fiscal Year ended at the end of such quarter, all reported
in the form provided to the Securities and Exchange Commission on Borrower's and
EOPT's Form 10Q, and (ii) and such other information reasonably requested by the
Administrative Agent and Documentation Agent or any Bank;

    (c) simultaneously with the delivery of each set of financial statements
referred to in clauses (a) and (b) above, a certificate of the chief financial
officer of the Borrower (i) setting forth in reasonable detail the calculations
required to establish whether the Borrower was in compliance with the
requirements of Section 5.8 on the date of such financial statements; (ii)
certifying (x) that such financial statements fairly present the financial
condition and the results of operations of the Borrower on the dates and for the
periods indicated, on the basis of GAAP, with respect to the Borrower subject,
in the case of interim financial statements, to normally recurring year-end
adjustments, and (y) that such officer has reviewed the terms of the Loan
Documents and has made, or caused to be made under his or her supervision, a
review in reasonable detail of the business and condition of the Borrower during
the period beginning on the date through which the last such review was made
pursuant to this Section 5.1(c) (or, in the case of the first certification
pursuant to this Section 5.1(c), the Closing Date) and ending on a date not more
than ten (10) Business Days prior to the date of such delivery and that (1) on
the basis of such financial statements and such review of the Loan Documents, no
Event of Default existed under Section 6.1(b) with respect to Sections 5.8 and
5.9 at or as of the date of said financial statements, and (2) on the basis of
such review of the Loan Documents and the business and condition of the
Borrower, to the best knowledge of such officer, as of the last day of the
period covered by such certificate no Default or Event of Default under any
other provision of Section 6.1 occurred and is continuing or, if any such
Default or Event of Default has occurred and is continuing, specifying the
nature and extent thereof and, the action the Borrower proposes to take in
respect thereof. Such certificate shall set forth the calculations required to
establish the matters described in clauses (1) and (2) above;

    (d) (i) within five (5) Business Days after any officer of the Borrower
obtains knowledge of any Default, if such Default is then continuing, a
certificate of the chief financial officer, or other executive officer of the
Borrower setting forth the details thereof and the action which the Borrower is
taking or proposes to take with respect thereto; and (ii) promptly and in any
event within five (5) Business Days after the Borrower obtains knowledge
thereof, notice of (x) any litigation or governmental proceeding pending or
threatened against the Borrower or its directly or indirectly Real Property
Assets as to which there is a reasonable possibility of an adverse determination
and which, if adversely determined, is



                                       46
<PAGE>   51


likely to individually or in the aggregate, result in a Material Adverse Effect,
and (y) any other event, act or condition which is likely to result in a
Material Adverse Effect;

    (e) promptly upon the mailing thereof to the shareholders of EOPT generally,
copies of all financial statements, reports and proxy statements so mailed;

    (f) promptly upon the filing thereof, copies of all registration statements
(other than the exhibits thereto and any registration statements on Form S-8 or
its equivalent) and reports on Forms 10-K, 10-Q and 8-K (or their equivalents)
(other than the exhibits thereto, which exhibits will be provided upon request
therefor by any Bank) which EOPT shall have filed with the Securities and
Exchange Commission;

    (g) promptly and in any event within thirty (30) days, if and when any
member of the ERISA Group (i) gives or is required to give notice to the PBGC of
any "reportable event" (as defined in Section 4043 of ERISA) with respect to any
Plan which might constitute grounds for a termination of such Plan under Title
IV of ERISA, or knows that the plan administrator of any Plan has given or is
required to give notice of any such reportable event, a copy of the notice of
such reportable event given or required to be given to the PBGC; (ii) receives
notice of complete or partial withdrawal liability under Title IV of ERISA or
notice that any Multiemployer Plan is in reorganization, is insolvent or has
been terminated, a copy of such notice; (iii) receives notice from the PBGC
under Title IV of ERISA of an intent to terminate, impose liability (other than
for premiums under Section 4007 of ERISA) in respect of, or appoint a trustee to
administer any Plan, a copy of such notice; (iv) applies for a waiver of the
minimum funding standard under Section 412 of the Code, a copy of such
application; (v) gives notice of intent to terminate any Plan under Section
4041(c) of ERISA, a copy of such notice and other information filed with the
PBGC; (vi) gives notice of withdrawal from any Plan pursuant to Section 4063 of
ERISA, a copy of such notice; or (vii) fails to make any payment or contribution
to any Plan or Multiemployer Plan or in respect of any Benefit Arrangement or
makes any amendment to any Plan or Benefit Arrangement which has resulted or
could result in the imposition of a Lien or the posting of a bond or other
security, and in the case of clauses (i) through (vii) above, which event could
result in a Material Adverse Effect, a certificate of the chief financial
officer or the chief accounting officer of the Borrower setting forth details as
to such occurrence and action, if any, which the Borrower or applicable member
of the ERISA Group is required or proposes to take;

    (h) promptly and in any event within ten (10) days after the Borrower
obtains actual knowledge of any of the following events, a certificate of the
Borrower, executed by an officer of the Borrower, specifying the nature of such
condition, and the Borrower's or, if the Borrower has actual knowledge thereof,
the Environmental Affiliate's proposed initial response thereto: (i) the receipt
by the Borrower, or any of the Environmental Affiliates of any communication
(written or oral), whether from a governmental authority, citizens group,
employee or otherwise, that alleges that the Borrower, or any of the
Environmental Affiliates, is not in compliance with applicable Environmental
Laws, and such noncompliance is likely to have a Material Adverse Effect, (ii)
the existence of any Environmental Claim pending against the Borrower or any
Environmental Affiliate and such Environmental Claim is likely to have a
Material Adverse Effect or (iii) any release, emission, discharge or disposal of
any Material of Environmental Concern that is likely to form the basis of any



                                       47
<PAGE>   52

Environmental Claim against the Borrower or any Environmental Affiliate which in
any such event is likely to have a Material Adverse Effect;

    (i) promptly and in any event within five (5) Business Days after receipt of
any notices or correspondence from any company or agent for any company
providing insurance coverage to the Borrower relating to any loss which is
likely to result in a Material Adverse Effect, copies of such notices and
correspondence; and

    (j) from time to time such additional information regarding the financial
position or business of the Borrower, EOPT and their Subsidiaries as the
Administrative Agent, at the request of any Bank, may reasonably request in
writing, so long as disclosure of such information could not result in a
violation of, or expose the Borrower, EOPT or their Subsidiaries to any material
liability under, any applicable law, ordinance or regulation or any agreements
with unaffiliated third parties that are binding on the Borrower, EOPT or any of
their Subsidiaries or on any Property of any of them.

    SECTION 5.2. Payment of Obligations. The Borrower, EOPT and their
Consolidated Subsidiaries will pay and discharge, at or before maturity, all
their respective material obligations and liabilities including, without
limitation, any obligation pursuant to any agreement by which it or any of its
properties is bound, in each case where the failure to so pay or discharge such
obligations or liabilities is likely to result in a Material Adverse Effect, and
will maintain in accordance with GAAP, appropriate reserves for the accrual of
any of the same.

    SECTION 5.3. Maintenance of Property; Insurance; Leases.

    (a) The Borrower will keep, and will cause each Consolidated Subsidiary to
keep, all property useful and necessary in its business, including without
limitation its Real Property Assets (for so long as it constitutes Real Property
Assets), in good repair, working order and condition, ordinary wear and tear
excepted, in each case where the failure to so maintain and repair will have a
Material Adverse Effect.

    (b)  The Borrower shall maintain, or cause to be maintained, insurance
comparable to that described in Section 4.24 hereof with insurers meeting the
qualifications described therein, which insurance shall in any event not provide
for less coverage than insurance customarily carried by owners of properties
similar to, and in the same locations as, Borrower's Real Property Assets. The
Borrower will deliver to the Administrative Agent upon the reasonable request of
the Administrative Agent from time to time (i) full information as to the
insurance carried, (ii) within five (5) days of receipt of notice from any
insurer a copy of any notice of cancellation or material change in coverage from
that existing on the date of this Agreement and (iii) forthwith, notice of any
cancellation or nonrenewal of coverage by the Borrower.

    SECTION 5.4. Maintenance of Existence. The Borrower and EOPT each will
preserve, renew and keep in full force and effect, its partnership and trust
existence and its respective rights, privileges and franchises necessary for the
normal conduct of business unless the failure to maintain such rights and
franchises does not have a Material Adverse Effect.

    SECTION 5.5. Compliance with Laws. The Borrower and EOPT will, and will
cause their Subsidiaries to, comply in all material respects with all applicable





                                       48
<PAGE>   53


laws, ordinances, rules, regulations, and requirements of governmental
authorities (including, without limitation, Environmental Laws, and all zoning
and building codes with respect to its Real Property Assets and ERISA and the
rules and regulations thereunder and all federal securities laws) except where
the necessity of compliance therewith is contested in good faith by appropriate
proceedings or where the failure to do so will not have a Material Adverse
Effect or expose Administrative Agent, Documentation Agent or Banks to any
material liability therefor.

    SECTION 5.6. Inspection of Property, Books and Records. The Borrower will
keep proper books of record and account in which full, true and correct entries
shall be made of all dealings and transactions in relation to its business and
activities in conformity with GAAP, modified as required by this Agreement and
applicable law; and will permit representatives of any Bank at such Bank's
expense to visit and inspect any of its properties, including without limitation
its Real Property Assets, and so long as disclosure of such information could
not result in a violation of, or expose the Borrower, EOPT or their Subsidiaries
to any material liability under, any applicable law, ordinance or regulation or
any agreements with unaffiliated third parties that are binding on the Borrower,
EOPT or any of their Subsidiaries or on any Property of any of them, to examine
and make abstracts from any of its books and records and to discuss its affairs,
finances and accounts with its officers and independent public accountants, all
at such reasonable times during normal business hours, upon reasonable prior
notice and as often as may reasonably be desired. Administrative Agent shall
coordinate any such visit or inspection to arrange for review by any Bank
requesting any such visit or inspection.

    SECTION 5.7. Existence. The Borrower shall do or cause to be done, all
things necessary to preserve and keep in full force and effect its, EOPT's and
their Consolidated Subsidiaries' existence and its patents, trademarks,
servicemarks, tradenames, copyrights, franchises, licenses, permits,
certificates, authorizations, qualifications, accreditation, easements, rights
of way and other rights, consents and approvals the nonexistence of which is
likely to have a Material Adverse Effect.

    SECTION 5.8. Financial Covenants.

    (a) Total Liabilities to Total Asset Value. Prior to June 30, 1998, Borrower
shall not permit the ratio of Total Liabilities to Total Asset Value of Borrower
to exceed 0.55:1 at any time. From and after July 1, 1998, Borrower shall not
permit the ratio of Total Liabilities to Total Asset Value of Borrower to exceed
0.50:1 at any time.

    (b) EBITDA to Interest Expense Ratio. Borrower shall not permit the ratio of
EBITDA for the then most recently completed Fiscal Quarter to Interest Expense
for the then most recently completed Fiscal Quarter to be less than 2.00:1.

    (c) [Intentionally Omitted.]

    (d) Cash Flow to Fixed Charges Ratio. Borrower shall not permit the ratio of
Cash Flow for the then most recently completed Fiscal Quarter to Fixed Charges
for the then most recently completed Fiscal Quarter to be less than 1.5:1.

    (e)  Secured Debt to Total Asset Value. Borrower shall not permit the
ratio of Secured Debt to Total Asset Value of Borrower to exceed 0.40:1 at any
time.

                                       49
<PAGE>   54

    (f)  Unencumbered Pool. Borrower shall not permit the ratio of the
outstanding Unsecured Debt to Unencumbered Asset Value to exceed 0.55:1 at any
time.

    (g) Unencumbered Net Operating Income to Unsecured Debt Service. Borrower
shall not permit the ratio of Unencumbered Net Operating Income for the then
most recently completed Fiscal Quarter to Unsecured Debt Service for the then
most recently completed Fiscal Quarter to be less than 2.0:1.

    (h) Minimum Tangible Net Worth. The Consolidated Tangible Net Worth of the
Borrower determined in conformity with GAAP will at no time be less than the sum
of (i) $5,500,000,000, and (ii) seventy percent (70%) of all Net Offering
Proceeds received by EOPT or Borrower after December 31, 1997.

    (i) Dividends. The Borrower will not, as determined on an aggregate annual
basis, pay any partnership distributions in excess of 90% of the Borrower's FFO
for such year. During the continuance of a monetary Event of Default, Borrower
shall only pay partnership distributions that are necessary to enable EOPT to
make those dividends necessary to maintain EOPT's status as a real estate
investment trust.

    (j) Permitted Holdings. Borrower's primary business will be the ownership,
operation and development of Office Properties and Parking Properties and any
other business activities of Borrower and its Subsidiaries will remain
incidental thereto. Notwithstanding the foregoing, Borrower and its Subsidiaries
may acquire or maintain Permitted Holdings if and so long as the aggregate value
of Permitted Holdings, whether held directly or indirectly by Borrower does not
exceed, at any time, fifteen percent (15%) of Total Asset Value of Borrower
unless a greater percentage is approved by the Majority Banks (which approval
shall not be unreasonably withheld, conditioned or delayed), provided, however,
Borrower and its Subsidiaries may not acquire or maintain Unimproved Assets if
and to the extent that the aggregate value of Unimproved Assets, whether held
directly or indirectly by Borrower exceeds, at any time, ten percent (10%) of
Total Asset Value of Borrower unless a greater percentage is approved by the
Majority Banks (which approval shall not be unreasonably withheld, conditioned
or delayed). For purposes of calculating the foregoing percentage the value of
Unimproved Assets shall be calculated in the manner that Total Asset Value is
determined.

    (k) No Liens. Borrower and EOPT shall not, and shall not allow any of their
Subsidiaries, Financing Partnerships or Joint Venture Subsidiaries to, allow any
Qualifying Unencumbered Property (or any equity interests in such Property that
are owned directly or indirectly by Borrower, EOPT or any Joint Venture Parent),
that is necessary to comply with the provisions of Sections 5.8(f) and (g)
hereof, to become subject to a Lien that secures the Indebtedness of any Person,
other than Permitted Liens.

    (l)  Calculation. Each of the foregoing ratios and financial requirements
shall be calculated as of the last day of each Fiscal Quarter.

    SECTION 5.9. Restriction on Fundamental Changes. (a) Neither the Borrower
nor EOPT shall enter into any merger or consolidation without obtaining the
prior written consent thereto in writing of the Majority Banks, which consent
shall not be unreasonably withheld, conditioned or delayed, unless (i) the





                                       50
<PAGE>   55

Borrower or EOPT is the surviving entity, (ii) the entity which is merged into
Borrower or EOPT is predominantly in the commercial real estate business, (iii)
the creditworthiness of the surviving entity's long term unsecured debt or
implied senior debt, as applicable, is not lower than Borrower's or EOPT's
creditworthiness two months immediately preceding such merger, and (iv) the then
fair market value of the assets of the entity which is merged into the Borrower
or EOPT is less than twenty-five percent (25%) of the Borrower's or EOPT's then
Total Asset Value following such merger. Neither the Borrower nor EOPT shall
liquidate, wind-up or dissolve (or suffer any liquidation or dissolution),
discontinue its business or convey, lease, sell, transfer or otherwise dispose
of, in one transaction or series of transactions, all or substantially all of
its business or property, whether now or hereafter acquired. Nothing in this
Section shall be deemed to prohibit the sale or leasing of portions of the Real
Property Assets in the ordinary course of business.

    (b) The Borrower shall not amend its agreement of limited partnership or
other organizational documents in any manner that would have a Material Adverse
Effect without the Majority Banks' consent, which shall not be unreasonably
withheld. Without limitation of the foregoing, no Person shall be admitted as a
general partner of the Borrower other than EOPT and Zell/Merrill Lynch Real
Estate Opportunity Partners Limited Partnership II. EOPT shall not amend its
declaration of trust, by-laws, or other organizational documents in any manner
that would have a Material Adverse Effect without the Majority Banks' consent,
which shall not be unreasonably withheld. The Borrower shall not make any
"in-kind" transfer of any of its property or assets to any of its constituent
partners.

    (c) Subject to the provisions of clause (b) above, the Borrower shall
deliver to Administrative Agent copies of all amendments to its agreement of
limited partnership or to EOPT's declaration of trust, by-laws, or other
organizational documents no less than ten (10) days after the effective date of
any such amendment.

    SECTION 5.10. Changes in Business. (a) Except for Permitted Holdings,
neither the Borrower nor EOPT shall enter into any business which is
substantially different from that conducted by the Borrower or EOPT on the
Closing Date after giving effect to the transactions contemplated by the Loan
Documents. The Borrower shall carry on its business operations through the
Borrower, its Consolidated Subsidiaries and its Investment Affiliates.

    (b) Except for Permitted Holdings, Borrower shall not engage in any line of
business other than ownership, operation and development of Office Properties
and Parking Properties and the provision of services incidental thereto, whether
directly or through its Consolidated Subsidiaries and Investment Affiliates.

    SECTION 5.11. EOPT Status.

    (a) Status. EOPT shall at all times (i) remain a publicly traded company
listed for trading on the New York Stock Exchange, and (ii) maintain its status
as a self-directed and self-administered real estate investment trust under the
Code.

    (b) Indebtedness. EOPT shall not, directly or indirectly, create, incur,
assume or otherwise become or remain directly or indirectly liable with respect
to, any Indebtedness, except:



                                       51
<PAGE>   56

              (1) the Obligations; and

              (2) Indebtedness of Borrower for which there is recourse to EOPT
    which, after giving effect thereto, may be incurred or may remain
    outstanding without giving rise to an Event of Default or Default under any
    provision of this Article V.

    (c) Restriction on Fundamental Changes.

              (1) EOPT shall not have an investment in any Person other than (i)
    Borrower, (ii) directly or indirectly in Financing Partnerships, and (iii)
    the interests identified on Schedule 5.11(c)(1) as being owned by EOPT.

              (2) EOPT shall not acquire an interest in any Property other than
    securities issued by Borrower and Financing Partnerships and the interests
    identified on Schedule 5.11(c)(2) attached hereto.

              (3)  None of Zell/Merrill Lynch Real Estate Opportunity Partners
    Limited Partnership, Zell/Merrill Lynch Real Estate Opportunity Partners
    Limited Partnership II, Zell/Merrill Lynch Real Estate Opportunity Partners
Limited Partnership III or Zell/Merrill Lynch Real Estate Opportunity Partners
Limited Partnership IV shall have any investments or own any assets other than
in their respective partnership interests in Borrower.

              (4) Neither of EOP-QRS Trust nor EOP-QRS LaJolla Trust shall have
    any investments or own any assets other than their permitted ownership
    interests Financing Subsidiaries.

    (d) Environmental Liabilities. Neither EOPT nor any of its Subsidiaries
shall become subject to any Environmental Claim which has a Material Adverse
Effect, including, without limitation, any arising out of or related to (i) the
release or threatened release of any Material of Environmental Concern into the
environment, or any remedial action in response thereto, or (ii) any violation
of any Environmental Laws. Notwithstanding the foregoing provision, EOPT shall
have the right to contest in good faith any claim of violation of an
Environmental Law by appropriate legal proceedings and shall be entitled to
postpone compliance with the obligation being contested as long as (i) no Event
of Default shall have occurred and be continuing, (ii) EOPT shall have given
Administrative Agent prior written notice of the commencement of such contest,
(iii) noncompliance with such Environmental Law shall not subject EOPT or such
Subsidiary to any criminal penalty or subject Administrative Agent,
Documentation Agent or any Bank to pay any civil penalty or to prosecution for a
crime, and (iv) no portion of any Property material to Borrower or its condition
or prospects shall be in substantial danger of being sold, forfeited or lost, by
reason of such contest or the continued existence of the matter being contested.

    (e) Disposal of Partnership Interests. EOPT will not directly or indirectly
convey, sell, transfer, assign, pledge or otherwise encumber or dispose of any
of its partnership interests in Borrower or any of its equity interest in any of
the partners of the Borrower as of the date hereof (except in connection with
the dissolution or liquidation of such partners of the Borrower), except for the
reduction of EOPT's interest in the Borrower arising from Borrower's issuance of
partnership interests in the Borrower or the retirement of preference units by
Borrower. EOPT will continue to be the managing general partner of Borrower and
of each Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership,
Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership II,



                                       52
<PAGE>   57

Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership III, and
Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership IV, and
will not permit such Persons to sell, transfer, assign, pledge or otherwise
encumber or dispose of any of their respective partnership interests in the
Borrower, except for the reduction of such partners' interest in the Borrower
arising from the Borrower's issuance of partnership interests in the Borrower or
the retirement of preference units by the Borrower and except in connection with
the dissolution or liquidation of such partners.

    SECTION 5.12. Other Indebtedness. Borrower and EOPT shall not allow any of
their Subsidiaries, Financing Partnerships or Joint Venture Subsidiaries that
own, directly or indirectly, any Qualifying Unencumbered Property to directly or
indirectly create, incur, assume or otherwise become or remain liable with
respect to any Indebtedness other than trade debt incurred in the ordinary
course of business and Indebtedness owing to Borrower, if the resulting failure
of such Property to qualify as a Qualifying Unencumbered Property would result
in an Event of Default under Section 5.8.

    SECTION 5.13. Forward Equity Contracts. If Borrower shall enter into any
forward equity contracts, Borrower may only settle the same by delivery of
stock, it being agreed that if Borrower shall settle the same with cash, the
same shall constitute an Event of Default hereunder.


                                   ARTICLE VI

                                    DEFAULTS

    SECTION 6.1. Events of Default. An "Event of Default" shall have occurred
if one or more of the following events shall have occurred and be continuing:

    (a) the Borrower shall fail to pay when due any principal of any Loan, or
the Borrower shall fail to pay when due interest on any Loan or any fees or any
other amount payable to Administrative Agent, Documentation Agent, Syndication
Agent or the Banks hereunder and the same shall continue for a period of five
(5) days after the same becomes due;

    (b) the Borrower shall fail to observe or perform any covenant contained in
Section 5.8, Section 5.9(a) or (b), Section 5.10, Section 5.11(a), (b) or (c),
Section 5.12 or Section 5.13;

    (c) the Borrower shall fail to observe or perform any covenant or agreement
contained in this Agreement (other than those covered by clause (a), (b), (e),
(f), (g), (h), (j), (n) or (o) of this Section 6.1) for 30 days after written
notice thereof has been given to the Borrower by the Administrative Agent, or if
such default is of such a nature that it cannot with reasonable effort be
completely remedied within said period of thirty (30) days such additional
period of time as may be reasonably necessary to cure same, provided Borrower
commences such cure within said thirty (30) day period and diligently prosecutes
same, until completion, but in no event shall such extended period exceed ninety
(90) days;

    (d) any representation, warranty, certification or statement made by the
Borrower in this Agreement or in any certificate, financial statement or other
document delivered pursuant to this Agreement shall prove to have been incorrect
in any material respect when made (or deemed made) and, with respect to such



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<PAGE>   58

representations, warranties, certifications or statements not known by the
Borrower at the time made or deemed made to be incorrect, the defect causing
such representation or warranty to be incorrect when made (or deemed made) is
not removed within thirty (30) days after written notice thereof from
Administrative Agent to Borrower;

    (e) the Borrower, EOPT, any Subsidiary or any Investment Affiliate shall
default in the payment when due (whether by scheduled maturity, required
prepayment, acceleration, demand or otherwise) of any amount owing in respect of
any Recourse Debt (other than the Obligations) for which the aggregate
outstanding principal amount exceeds $10,000,000 and such default shall continue
beyond the giving of any required notice and the expiration of any applicable
grace period and such default has not been waived, in writing, by the holder of
any such Debt; or the Borrower, EOPT, any Subsidiary or any Investment Affiliate
shall default in the performance or observance of any obligation or condition
with respect to any such Recourse Debt or any other event shall occur or
condition exist beyond the giving of any required notice and the expiration of
any applicable grace period, if the effect of such default, event or condition
is to accelerate the maturity of any such indebtedness or to permit (without any
further requirement of notice or lapse of time) the holder or holders thereof,
or any trustee or agent for such holders, to accelerate the maturity of any such
indebtedness;

    (f) the Borrower or EOPT shall commence a voluntary case or other proceeding
seeking liquidation, reorganization or other relief with respect to itself or
its debts under any bankruptcy, insolvency or other similar law now or hereafter
in effect or seeking the appointment of a trustee, receiver, liquidate,
custodian or other similar official of it or any substantial part of its
property, or shall consent to any such relief or to the appointment of or taking
possession by any such official in an involuntary case or other proceeding
commenced against it, or shall make a general assignment for the benefit of
creditors, or shall fail generally to pay its debts as they become due, or shall
take any action to authorize any of the foregoing;

    (g) an involuntary case or other proceeding shall be commenced against the
Borrower or EOPT seeking liquidation, reorganization or other relief with
respect to it or its debts under any bankruptcy, insolvency or other similar law
now or hereafter in effect or seeking the appointment of a trustee, receiver,
liquidator, custodian or other similar official of it or any substantial part of
its property, and such involuntary case or other proceeding shall remain
undismissed and unstayed for a period of 90 days; or an order for relief shall
be entered against the Borrower or EOPT under the federal bankruptcy laws as now
or hereafter in effect;

    (h) one or more final, non-appealable judgments or decrees in an aggregate
amount of Twenty Million Dollars ($20,000,000) or more shall be entered by a
court or courts of competent jurisdiction against EOPT, the Borrower or, to the
extent of any recourse to EOPT or the Borrower, any of its Consolidated
Subsidiaries (other than any judgment as to which, and only to the extent, a
reputable insurance company has acknowledged coverage of such claim in writing)
and (i) any such judgments or decrees shall not be stayed, discharged, paid,
bonded or vacated within thirty (30) days or (ii) enforcement proceedings shall
be commenced by any creditor on any such judgments or decrees;

    (i) there shall be a change in the majority of the Board of Trustees of EOPT
during any twelve (12) month period, excluding any change in directors resulting
from (x) the death or disability of any director, or (y) satisfaction






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<PAGE>   59

of any requirement for the majority of the members of the board of directors or
trustees of EOPT to qualify under applicable law as independent trustees or (z)
the replacement of any trustee who is an officer or employee of EOPT or an
affiliate of EOPT with any other officer or employee of EOPT or an affiliate of
EOPT;

    (j) any Person (including affiliates of such Person) or "group" (as such
term is defined in applicable federal securities laws and regulations) shall
acquire more than thirty percent (30%) of the common shares of EOPT;

    (k) EOPT shall cease at any time to qualify as a real estate investment
trust under the Code;

    (l) if any Termination Event with respect to a Plan, Multiemployer Plan or
Benefit Arrangement shall occur as a result of which Termination Event or Events
any member of the ERISA Group has incurred or may incur any liability to the
PBGC or any other Person and the sum (determined as of the date of occurrence of
such Termination Event) of the insufficiency of such Plan, Multiemployer Plan or
Benefit Arrangement and the insufficiency of any and all other Plans,
Multiemployer Plans and Benefit Arrangements with respect to which such a
Termination Event shall occur and be continuing (or, in the case of a Multiple
Employer Plan with respect to which a Termination Event described in clause (ii)
of the definition of Termination Event shall occur and be continuing and in the
case of a liability with respect to a Termination Event which is or could be a
liability of the Borrower or EOPT rather than a liability of the Plan, the
liability of the Borrower or EOPT) is equal to or greater than $10,000,000 and
which the Administrative Agent reasonably determines will have a Material
Adverse Effect;

    (m) if, any member of the ERISA Group shall commit a failure described in
Section 302(f)(1) of ERISA or Section 412(n)(1) of the Code and the amount of
the lien determined under Section 302(f)(3) of ERISA or Section 412(n)(3) of the
Code that could reasonably be expected to be imposed on any member of the ERISA
Group or their assets in respect of such failure shall be equal to or greater
than $10,000,000 and which the Administrative Agent reasonably determines will
have a Material Adverse Effect;

    (n) at any time, for any reason the Borrower seeks to repudiate its
obligations under any Loan Document or EOPT seeks to repudiate its obligations
under the EOPT Guaranty.

    (o) a default beyond any applicable notice or grace period under any of the
other Loan Documents;

    (p) any assets of Borrower shall constitute "assets" (within the meaning of
ERISA or Section 4975 of the Code, including but not limited to 29 C.F.R.
Section 2510.3-101 or any successor regulation thereto) of an "employee benefit
plan" within the meaning of Section 3(3) of ERISA or a "plan" within the meaning
of Section 4975(e)(1) of the Code; or

    (q) the Note, the Loan, the Obligations, the EOPT Guaranty or any of the
Loan Documents or the exercise of any of the Administrative Agent's, the
Documentation Agent's or any of the Bank's rights in connection therewith shall
constitute a prohibited transaction under ERISA and/or the Code.



                                       55
<PAGE>   60

    SECTION 6.2. Rights and Remedies. (a) Upon the occurrence of any Event of
Default described in Sections 6.1(f), (g), (p) or (q), the Commitments and the
Swingline Commitment shall immediately terminate and the unpaid principal amount
of, and any and all accrued interest on, the Loans and any and all accrued fees
and other Obligations hereunder shall automatically become immediately due and
payable, with all additional interest from time to time accrued thereon and
without presentation, demand, or protest or other requirements of any kind
(including, without limitation, valuation and appraisement, diligence,
presentment, notice of intent to demand or accelerate and notice of
acceleration), all of which are hereby expressly waived by the Borrower; and
upon the occurrence and during the continuance of any other Event of Default,
the Administrative Agent may (and upon the demand of the Required Banks shall),
by written notice to the Borrower, in addition to the exercise of all of the
rights and remedies permitted the Administrative Agent and the Banks at law or
equity or under any of the other Loan Documents, declare that the commitments
are terminated and declare the unpaid principal amount of and any and all
accrued and unpaid interest on the Loans and any and all accrued fees and other
Obligations hereunder to be, and the same shall thereupon be, immediately due
and payable with all additional interest from time to time accrued thereon and
(except as otherwise provided in the Loan Documents) without presentation,
demand, or protest or other requirements of any kind (including, without
limitation, valuation and appraisement, diligence, presentment, notice of intent
to demand or accelerate and notice of acceleration), all of which are hereby
expressly waived by the Borrower.

    (b) Notwithstanding anything to the contrary contained in this Agreement or
in any other Loan Document, the Documentation Agent, the Administrative Agent,
and the Banks each agree that any exercise or enforcement of the rights and
remedies granted to the Documentation Agent, the Administrative Agent or the
Banks under this Agreement or at law or in equity with respect to this Agreement
or any other Loan Documents shall be commenced and maintained by the
Documentation Agent or the Administrative Agent on behalf of the Documentation
Agent, the Administrative Agent and/or the Banks. The Administrative Agent shall
act at the direction of the Required Banks in connection with the exercise of
any and all remedies at law, in equity or under any of the Loan Documents or, if
the Required Banks are unable to reach agreement, then, from and after an Event
of Default, the Administrative Agent may pursue such rights and remedies as it
may determine.

    SECTION 6.3. Notice of Default. The Administrative Agent shall give notice
to the Borrower under Section 6.1(c) and 6.1(d) promptly upon being requested to
do so by the Required Banks and shall thereupon notify all the Banks thereof.
Neither Administrative Agent nor Documentation Agent shall be deemed to have
knowledge or notice of the occurrence of any Default or Event of Default (other
than nonpayment of principal of or interest on the Loans) unless Administrative
Agent or Documentation Agent has received notice in writing from a Bank or
Borrower referring to this Agreement or the other Loan Documents, describing
such event or condition. Should Administrative Agent or Documentation Agent
receive notice of the occurrence of an Default or Event of Default expressly
stating that such notice is a notice of an Default or Event of Default, or
should Administrative Agent or Documentation Agent send Borrower a notice of
Default or Event of Default, Administrative Agent or Documentation Agent, as
applicable, shall promptly give notice thereof to each Bank.

    SECTION 6.4. Distribution of Proceeds after Default. Notwithstanding
anything contained herein to the contrary but subject to the provisions of
Section 9.16 hereof , from and after an Event of Default, to the extent proceeds





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<PAGE>   61

are received by Administrative Agent, such proceeds will be distributed to the
Banks pro rata in accordance with the unpaid principal amount of the Loans
(giving effect to any participations granted therein pursuant to Section 2.3 and
Section 9.4).

                                   ARTICLE VII

                                   THE AGENTS

    SECTION 7.1. Appointment and Authorization. Each Bank irrevocably appoints
and authorizes the Administrative Agent, Documentation Agent and the Syndication
Agent to take such action as agent on its behalf and to exercise such powers
under this Agreement and the other Loan Documents as are delegated to the
Administrative Agent, Documentation Agent and the Syndication Agent by the terms
hereof or thereof, together with all such powers as are reasonably incidental
thereto. Except as set forth in Sections 7.8 and 7.9 hereof, the provisions of
this Article VII are solely for the benefit of Administrative Agent,
Documentation Agent, the Syndication Agent and the Banks, and Borrower shall not
have any rights to rely on or enforce any of the provisions hereof. In
performing its functions and duties under this Agreement, Administrative Agent,
Documentation Agent and the Syndication Agent shall each act solely as an agent
of the Banks and do not assume and shall not be deemed to have assumed any
obligation toward or relationship of agency or trust with or for the Borrower.

    SECTION 7.2. Agency and Affiliates. NationsBank, N.A. and Bank of America,
National Trust and Savings Association shall have the same rights and powers
under this Agreement as any other Bank and may exercise or refrain from
exercising the same as though it were not the Administrative Agent or
Documentation Agent respectively, and NationsBank, N.A., Bank of America
National Trust and Savings Association, and their affiliates may accept deposits
from, lend money to, and generally engage in any kind of business with the
Borrower, EOPT or any Subsidiary or affiliate of the Borrower as if they were
not the Administrative Agent and Documentation Agent, respectively, hereunder,
and the term "Bank" and "Banks" shall include NationsBank, N.A. and Bank of
America National Trust and Savings Association, in their individual capacities.

    SECTION 7.3. Action by Administrative Agent and Documentation Agent. The
obligations of the Administrative Agent and Documentation Agent hereunder are
only those expressly set forth herein. Without limiting the generality of the
foregoing, the Administrative Agent and Documentation Agent shall not be
required to take any action with respect to any Default or Event of Default,
except as expressly provided in Article VI. The duties of Administrative Agent
and Documentation Agent shall be administrative in nature. Subject to the
provisions of Sections 7.1, 7.5 and 7.6, Administrative Agent and Documentation
Agent shall administer the Loans in the same manner as each administers its own
loans.

    SECTION 7.4. Consultation with Experts. As between Administrative Agent and
Documentation Agent on the one hand and the Banks on the other hand, the
Administrative Agent and Documentation Agent may consult with legal counsel (who
may be counsel for the Borrower), independent public accountants and other
experts selected by it and shall not be liable for any action taken or omitted
to be taken by it in good faith in accordance with the advice of such counsel,
accountants or experts.



                                       57
<PAGE>   62

    SECTION 7.5. Liability of Administrative Agent and Documentation Agent. As
between Administrative Agent and Documentation Agent on the one hand and the
Banks on the other hand, none of the Administrative Agent, the Documentation
Agent nor any of their affiliates nor any of their respective directors,
officers, agents or employees shall be liable for any action taken or not taken
by it in connection herewith (i) with the consent or at the request of the
Required Banks or (ii) in the absence of its own gross negligence or willful
misconduct. As between Administrative Agent and Documentation Agent on the one
hand and the Banks on the other hand, none of the Administrative Agent, the
Documentation Agent nor any of its directors, officers, agents or employees
shall be responsible for or have any duty to ascertain, inquire into or verify
(i) any statement, warranty or representation made in connection with this
Agreement or any borrowing hereunder; (ii) the performance or observance of any
of the covenants or agreements of the Borrower; (iii) the satisfaction of any
condition specified in Article III, except receipt of items required to be
delivered to the Administrative Agent or the Documentation Agent; or (iv) the
validity, effectiveness or genuineness of this Agreement, the other Loan
Documents or any other instrument or writing furnished in connection herewith.
As between Administrative Agent and Documentation Agent on the one hand and the
Banks on the other hand, neither the Administrative Agent nor the Documentation
Agent shall incur any liability by acting in reliance upon any notice, consent,
certificate, statement, or other writing (which may be a bank wire, telex or
similar writing) believed by it to be genuine or to be signed by the proper
party or parties.

    SECTION 7.6. Indemnification. Each Bank shall, ratably in accordance with
its Commitment, indemnify the Administrative Agent and the Documentation Agent
and their affiliates and their respective directors, officers, agents and
employees (to the extent not reimbursed by the Borrower) against any cost,
expense (including, without limitation, counsel fees and disbursements), claim,
demand, action, loss or liability (except such as result from such indemnitee's
gross negligence or willful misconduct) that such indemnitee may suffer or incur
in connection with its duties as Administrative Agent and/or Documentation Agent
under this Agreement, the other Loan Documents or any action taken or omitted by
such indemnitee hereunder. In the event that the Documentation Agent or the
Administrative Agent shall, subsequent to its receipt of indemnification
payment(s) from Banks in accordance with this section, recoup any amount from
the Borrower, or any other party liable therefor in connection with such
indemnification, the Documentation Agent or the Administrative Agent, as the
case may be, shall reimburse the Banks which previously made the payment(s) pro
rata, based upon the actual amounts which were theretofore paid by each Bank.
The Documentation Agent or the Administrative Agent, as the case may be, shall
reimburse such Banks so entitled to reimbursement within two (2) Business Days
of its receipt of such funds from the Borrower or such other party liable
therefor.

    SECTION 7.7. Credit Decision. Each Bank acknowledges that it has,
independently and without reliance upon the Administrative Agent, the
Documentation Agent, the Syndication Agent or any other Bank, and based on such
documents and information as it has deemed appropriate, made its own credit
analysis and decision to enter into this Agreement. Each Bank also acknowledges
that it will, independently and without reliance upon the Administrative Agent,
Documentation Agent, the Syndication Agent or any other Bank, and based on such
documents and information as it shall deem appropriate at the time, continue to
make its own credit decisions in taking or not taking any action under this
Agreement.



                                       58
<PAGE>   63

    SECTION 7.8. Successor Administrative Agent, Documentation Agent or
Syndication Agent. The Administrative Agent, the Documentation Agent or the
Syndication Agent may resign at any time by giving notice thereof to the Banks,
the Borrower and each other and the Administrative Agent, the Documentation
Agent or the Syndication Agent, as applicable, shall resign in the event its
Commitment (or, so long as J.P. Morgan Securities, Inc. is the Syndication
Agent, Morgan Guaranty Trust Company of New York's Commitment) is reduced to
less than Thirty Million Dollars ($30,000,000) unless as a result of a
cancellation or reduction in the aggregate Commitments. Upon any such
resignation, the Majority Banks shall have the right to appoint a successor
Administrative Agent, Documentation Agent or Syndication Agent, as applicable,
which successor Administrative Agent, successor Documentation Agent or successor
Syndication Agent (as applicable) shall, provided no Event of Default has
occurred and is then continuing, be subject to Borrower's approval, which
approval shall not be unreasonably withheld or delayed (except that Borrower
shall, in all events, be deemed to have approved Bank of America, National Trust
and Savings Association, as a successor Administrative Agent and NationsBank,
N.A., as a successor Documentation Agent). If no successor Administrative Agent,
Documentation Agent or Syndication Agent (as applicable) shall have been so
appointed by the Majority Banks and approved by the Borrower, and shall have
accepted such appointment, within 30 days after the retiring Administrative
Agent, Documentation Agent or Syndication Agent (as applicable) gives notice of
resignation, then the retiring Administrative Agent, retiring Documentation
Agent, or retiring Syndication Agent (as applicable) may, on behalf of the
Banks, appoint a successor Administrative Agent, Documentation Agent or
Syndication Agent (as applicable), which shall be the Administrative Agent, the
Documentation Agent or the Syndication Agent as the case may be, who shall act
until the Majority Banks shall appoint an Administrative Agent, Documentation
Agent or Syndication Agent. Any appointment of a successor Administrative Agent,
Documentation Agent or Syndication Agent by Majority Banks or the retiring
Administrative Agent, the Documentation Agent or the Syndication Agent pursuant
to the preceding sentence shall, provided no Event of Default has occurred and
is then continuing, be subject to the Borrower's approval, which approval shall
not be unreasonably withheld or delayed. Upon the acceptance of its appointment
as the Administrative Agent, Documentation Agent or Syndication Agent hereunder
by a successor Administrative Agent or successor Documentation Agent or
successor Syndication Agent, as applicable, such successor Administrative Agent,
successor Documentation Agent or successor Syndication Agent, as applicable,
shall thereupon succeed to and become vested with all the rights and duties of
the retiring Administrative Agent, retiring Documentation Agent or retiring
Syndication Agent, as applicable, and the retiring Administrative Agent, the
retiring Documentation Agent or the retiring Syndication Agent, as applicable,
shall be discharged from its duties and obligations hereunder. The rights and
duties of the Administrative Agent to be vested in any successor Administrative
Agent shall include, without limitation, the rights and duties as Swingline
Lender. After any retiring Administrative Agent's, retiring Documentation
Agent's or retiring Syndication Agent's resignation hereunder, the provisions of
this Article shall inure to its benefit as to any actions taken or omitted to be
taken by it while it was the Administrative Agent, the Documentation Agent or
the Syndication Agent, as applicable. For gross negligence or willful
misconduct, as determined by all the Banks (excluding for such determination
Administrative Agent or Documentation Agent in its capacity as a Bank, as
applicable), Administrative Agent, Documentation Agent or Syndication Agent may
be removed at any time by giving at least thirty (30) Business Days prior
written notice to Administrative Agent, Documentation Agent, Syndication Agent
and Borrower. Such resignation or removal





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<PAGE>   64


shall take effect upon the acceptance of appointment by a successor
Administrative Agent, Documentation Agent or Syndication Agent, as applicable,
in accordance with the provisions of this Section 7.8.

    SECTION 7.9. Consents and Approvals. All communications from Administrative
Agent to the Banks requesting the Banks' determination, consent, approval or
disapproval (i) shall be given in the form of a written notice to each Bank,
(ii) shall be accompanied by a description of the matter or item as to which
such determination, approval, consent or disapproval is requested, or shall
advise each Bank where such matter or item may be inspected, or shall otherwise
describe the matter or issue to be resolved, (iii) shall include, if
reasonably requested by a Bank and to the extent not previously provided to such
Bank, written materials and a summary of all oral information provided to
Administrative Agent by Borrower in respect of the matter or issue to be
resolved, and (iv) shall include Administrative Agent's recommended course of
action or determination in respect thereof. Each Bank shall reply promptly, but
in any event within ten (10) Business Days after receipt of the request therefor
from Administrative Agent (the "Bank Reply Period"). Unless a Bank shall give
written notice to Administrative Agent that it objects to the recommendation or
determination of Administrative Agent (together with a written explanation of
the reasons behind such objection) within the Bank Reply Period, such Bank shall
be deemed to have approved of or consented to such recommendation or
determination. With respect to decisions requiring the approval of the Required
Banks, Majority Banks or all the Banks, Administrative Agent shall submit its
recommendation or determination for approval of or consent to such
recommendation or determination to all Banks and upon receiving the required
approval or consent shall follow the course of action or determination of the
Required Banks, Majority Banks or all the Banks (and each non-responding Bank
shall be deemed to have concurred with such recommended course of action), as
the case may be.

                                  ARTICLE VIII

                             CHANGE IN CIRCUMSTANCES

    SECTION 8.1. Basis for Determining Interest Rate Inadequate or Unfair. If on
or prior to the first day of any Interest Period for any Euro-Dollar Borrowing
or Money Market IBOR Loan the Administrative Agent determines in good faith that
deposits in dollars (in the applicable amounts) are not being offered in the
relevant market for such Interest Period, the Administrative Agent shall
forthwith give notice thereof to the Borrower and the Banks, whereupon until the
Administrative Agent notifies the Borrower that the circumstances giving rise to
such suspension no longer exist, the obligations of the Banks to make
Euro-Dollar Loans shall be suspended. Unless the Borrower notifies the
Administrative Agent at least two Business Days before the date of (i) any
Euro-Dollar Borrowing for which a Notice of Borrowing has previously been given
that it elects not to borrow on such date, such Borrowing shall instead be made
as a Base Rate Borrowing, or (ii) any Money Market IBOR Borrowing for which a
Notice of Money Market Borrowing has previously been given, the Money Market
IBOR Loans comprising such Borrowing shall bear interest for each day from and
including the first day to but excluding the last day of the Interest Period
applicable thereto at the Base Rate for such day.

    SECTION 8.2. Illegality. If, on or after the date of this Agreement, the
adoption of any applicable law, rule or regulation, or any change in any
applicable law, rule or regulation, or any change in the interpretation or
administration thereof by any governmental authority, central bank or comparable
agency charged with the interpretation or




                                       60
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administration thereof, or compliance by any Bank (or its Euro-Dollar Lending
Office) with any request or directive (whether or not having the force of law)
made after the Closing Date of any such authority, central bank or comparable
agency shall make it unlawful for any Bank (or its Euro-Dollar Lending Office)
to make, maintain or fund its Euro-Dollar Loans, the Administrative Agent shall
forthwith give notice thereof to the other Banks and the Borrower, whereupon
until such Bank notifies the Borrower and the Administrative Agent that the
circumstances giving rise to such suspension no longer exist, the obligation of
such Bank to make Euro-Dollar Loans shall be suspended. With respect to
Euro-Dollar Loans, before giving any notice to the Administrative Agent pursuant
to this Section, such Bank shall designate a different Euro-Dollar Lending
Office if such designation will avoid the need for giving such notice and will
not, in the judgment of such Bank, be otherwise disadvantageous to such Bank. If
such Bank shall determine that it may not lawfully continue to maintain and fund
any of its outstanding Euro-Dollar Loans to maturity and shall so specify in
such notice, the Borrower shall be deemed to have delivered a Notice of Interest
Rate Election and such Euro-Dollar Loan shall be converted as of such date to a
Base Rate Loan (without payment of any amounts that Borrower would otherwise be
obligated to pay pursuant to Section 2.13 hereof with respect to Loans converted
pursuant to this Section 8.2) in an equal principal amount from such Bank (on
which interest and principal shall be payable contemporaneously with the related
Euro-Dollar Loans of the other Banks), and such Bank shall make such a Base Rate
Loan.

    If at any time, it shall be unlawful for any Bank to make, maintain or fund
its Euro-Dollar Loans, the Borrower shall have the right, upon five (5) Business
Day's notice to the Administrative Agent, to either (x) cause a bank, reasonably
acceptable to the Administrative Agent, to offer to purchase the Commitments of
such Bank for an amount equal to such Bank's outstanding Loans, and to become a
Bank hereunder, or obtain the agreement of one or more existing Banks to offer
to purchase the Commitments of such Bank for such amount, which offer such Bank
is hereby required to accept, or (y) to repay in full all Loans then outstanding
of such Bank, together with interest and all other amounts due thereon, upon
which event, such Bank's Commitments shall be deemed to be canceled pursuant to
Section 2.11(c).

    SECTION 8.3. Increased Cost and Reduced Return.

    (a) If, on or after (x) the date hereof in the case of Committed Loans made
pursuant to Section 2.1, or (y) the date of the related Money Market Quote (in
each case, the "Loan Effective Date"), in the case of any Money Market Loan, the
adoption of any applicable law, rule or regulation, or any change in any
applicable law, rule or regulation, or any change in the interpretation or
administration thereof by any governmental authority, central bank or comparable
agency charged with the interpretation or administration thereof, or compliance
by any Bank (or its Applicable Lending Office) with any request or directive
(whether or not having the force of law) made at the Closing Date of any such
authority, central bank or comparable agency shall impose, modify or deem
applicable any reserve (including, without limitation, any such requirement
imposed by the Board of Governors of the Federal Reserve System (but excluding
with respect to any Euro-Dollar Loan any such requirement reflected in an
applicable Euro-Dollar Reserve Percentage)), special deposit, insurance
assessment or similar requirement against assets of, deposits with or for the
account of, or credit extended by, any Bank (or its Applicable Lending Office)
or shall impose on any Bank (or its Applicable Lending Office) or on the
interbank market any other





                                       61
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condition materially more burdensome in nature, extent or consequence than those
in existence as of the Loan Effective Date affecting such Bank's Euro-Dollar
Loans, its Note, or its obligation to make Euro-Dollar Loans, and the result of
any of the foregoing is to increase the cost to such Bank (or its Applicable
Lending Office) of making or maintaining any Euro-Dollar Loan, or to reduce the
amount of any sum received or receivable by such Bank (or its Applicable Lending
Office) under this Agreement or under its Note with respect to such Euro-Dollar
Loans, by an amount deemed by such Bank to be material, then, within 15 days
after demand by such Bank (with a copy to the Administrative Agent and
Documentation Agent), the Borrower shall pay to such Bank such additional amount
or amounts (based upon a reasonable allocation thereof by such Bank to the
Euro-Dollar Loans made by such Bank hereunder) as will compensate such Bank for
such increased cost or reduction to the extent such Bank generally imposes such
additional amounts on other borrowers of such Bank in similar circumstances.

    (b) If any Bank shall have reasonably determined that, after the date
hereof, the adoption of any applicable law, rule or regulation regarding capital
adequacy, or any change in any such law, rule or regulation, or any change in
the interpretation or administration thereof by any governmental authority,
central bank or comparable agency charged with the interpretation or
administration thereof, or any request or directive regarding capital adequacy
(whether or not having the force of law) made after the Closing Date of any such
authority, central bank or comparable agency, has or would have the effect of
reducing the rate of return on capital of such Bank (or its Parent) as a
consequence of such Bank's obligations hereunder to a level below that which
such Bank (or its Parent) could have achieved but for such adoption, change,
request or directive (taking into consideration its policies with respect to
capital adequacy) by an amount reasonably deemed by such Bank to be material,
then from time to time, within 15 days after demand by such Bank (with a copy to
the Administrative Agent and Documentation Agent), the Borrower shall pay to
such Bank such additional amount or amounts as will compensate such Bank (or its
Parent) for such reduction to the extent such Bank generally imposes such
additional amounts on other borrowers of such Bank in similar circumstances.

    (c) Each Bank will promptly notify the Borrower and the Administrative Agent
of any event of which it has knowledge, occurring after the date hereof, which
will entitle such Bank to compensation pursuant to this Section and will
designate a different Applicable Lending Office if such designation will avoid
the need for, or reduce the amount of, such compensation and will not, in the
reasonable judgment of such Bank, be otherwise disadvantageous to such Bank. If
such Bank shall fail to notify Borrower of any such event within 90 days
following the end of the month during which such event occurred, then Borrower's
liability for any amounts described in this Section incurred by such Bank as a
result of such event shall be limited to those attributable to the period
occurring subsequent to the ninetieth (90th) day prior to the date upon which
such Bank actually notified Borrower of the occurrence of such event. A
certificate of any Bank claiming compensation under this Section and setting
forth a reasonably detailed calculation of the additional amount or amounts to
be paid to it hereunder shall be conclusive in the absence of demonstrable
error. In determining such amount, such Bank may use any reasonable averaging
and attribution methods.

    (d) If at any time, any Bank shall be owed amounts pursuant to this Section
8.3, the Borrower shall have the right, upon five (5) Business Day's notice to
the Administrative Agent to either (x) cause a bank, reasonably acceptable to
the Administrative Agent, to offer to purchase the Commitments of such Bank for
an amount equal to such Bank's outstanding Loans, and to become a Bank




                                       62
<PAGE>   67

hereunder, or to obtain the agreement of one or more existing Banks to offer to
purchase the Commitments of such Bank for such amount, which offer such Bank is
hereby required to accept, or (y) to repay in full all Loans then outstanding of
such Bank, together with interest and all other amounts due thereon, upon which
event, such Bank's Commitment shall be deemed to be canceled pursuant to Section
2.11(c).

    SECTION 8.4. Taxes.

    (a) Any and all payments by the Borrower to or for the account of any Bank,
the Documentation Agent or the Administrative Agent hereunder or under any other
Loan Document shall be made free and clear of and without deduction for any and
all present or future taxes, duties, levies, imposts, deductions, charges or
withholdings, and all liabilities with respect thereto, excluding, in the case
of each Bank, the Documentation Agent and the Administrative Agent, taxes
imposed on its income, and franchise taxes imposed on it, by the jurisdiction
under the laws of which such Bank, the Documentation Agent or the Administrative
Agent (as the case may be) is organized or any political subdivision thereof
and, in the case of each Bank, taxes imposed on its income, and franchise or
similar taxes imposed on it, by the jurisdiction of such Bank's Applicable
Lending Office or any political subdivision thereof or by any other jurisdiction
(or any political subdivision thereof) as a result of a present or former
connection between such Bank, Documentation Agent or Administrative Agent and
such other jurisdiction or by the United States (all such non-excluded taxes,
duties, levies, imposts, deductions, charges, withholdings and liabilities being
hereinafter referred to as "Non-Excluded Taxes"). If the Borrower shall be
required by law to deduct any Non-Excluded Taxes from or in respect of any sum
payable hereunder or under any Note, (i) the sum payable shall be increased as
necessary so that after making all required deductions (including, without
limitation, deductions applicable to additional sums payable under this Section
8.4) such Bank, the Documentation Agent or the Administrative Agent (as the case
may be) receives an amount equal to the sum it would have received had no such
deductions been made, (ii) the Borrower shall make such deductions, (iii) the
Borrower shall pay the full amount deducted to the relevant taxation authority
or other authority in accordance with applicable law and (iv) the Borrower shall
furnish to the Administrative Agent, at its address referred to in Section 9.1,
the original or a certified copy of a receipt evidencing payment thereof.

    (b) In addition, the Borrower agrees to pay any present or future stamp or
documentary taxes and any other excise or property taxes, or charges or similar
levies which arise from any payment made hereunder or under any Note or from the
execution or delivery of, or otherwise with respect to, this Agreement or any
Note (hereinafter referred to as "Other Taxes").

    (c) The Borrower agrees to indemnify each Bank, the Documentation Agent and
the Administrative Agent for the full amount of Non-Excluded Taxes or Other
Taxes (including, without limitation, any Non-Excluded Taxes or Other Taxes
imposed or asserted by any jurisdiction on amounts payable under this Section
8.4) paid by such Bank, the Documentation Agent or the Administrative Agent (as
the case may be) and, so long as such Bank, Documentation Agent or
Administrative Agent has promptly paid any such Non-Excluded Taxes or Other
Taxes, any liability for penalties and interest arising therefrom or with
respect thereto. This indemnification shall be made within 15 days from the date
such Bank, the Documentation Agent or the Administrative Agent (as the case may
be) makes demand therefor.



                                       63
<PAGE>   68

    (d) Each Bank organized under the laws of a jurisdiction outside the United
States, on or prior to the date of its execution and delivery of this Agreement
in the case of each Bank listed on the signature pages hereof and on or prior to
the date on which it becomes a Bank in the case of each other Bank, shall
provide the Borrower with (A) two duly completed copies of Internal Revenue
Service form 1001 or 4224, as appropriate, or any successor form prescribed by
the Internal Revenue Service, and (B) an Internal Revenue Service Form W-8 or
W-9, or any successor form prescribed by the Internal Revenue Service, and shall
provide Borrower with two further copies of any such form or certification on or
before the date that any such form or certification expires or becomes obsolete
and after the occurrence of any event requiring a change in the most recent form
previously delivered by it to Borrower, certifying (i) in the case of a Form
1001 or 4224, that such Bank is entitled to benefits under an income tax treaty
to which the United States is a party which reduces the rate of withholding tax
on payments of interest or certifying that the income receivable pursuant to
this Agreement is effectively connected with the conduct of a trade or business
in the United States, and (ii) in the case of a Form W-8 or W-9, that it is
entitled to an exemption from United States backup withholding tax. If the form
provided by a Bank at the time such Bank first becomes a party to this Agreement
indicates a United States interest withholding tax rate in excess of zero,
withholding tax at such rate shall be considered excluded from "Non-Excluded
Taxes" as defined in Section 8.4(a).

    (e) For any period with respect to which a Bank has failed to provide the
Borrower with the appropriate form pursuant to Section 8.4(d) (unless such
failure is due to a change in treaty, law or regulation occurring subsequent to
the date on which a form originally was required to be provided), such Bank
shall not be entitled to indemnification under Section 8.4(c) with respect to
Non-Excluded Taxes imposed by the United States; provided, however, that should
a Bank, which is otherwise exempt from or subject to a reduced rate of
withholding tax, become subject to Non-Excluded Taxes because of its failure to
deliver a form required hereunder, the Borrower shall take such steps as such
Bank shall reasonably request to assist such Bank to recover such Taxes so long
as Borrower shall incur no cost or liability as a result thereof.

    (f) If the Borrower is required to pay additional amounts to or for the
account of any Bank pursuant to this Section 8.4, then such Bank will change the
jurisdiction of its Applicable Lending Office so as to eliminate or reduce any
such additional payment which may thereafter accrue if such change, in the
judgment of such Bank, is not otherwise disadvantageous to such Bank.

    (g) If at any time, any Bank shall be owed amounts pursuant to this Section
8.4, the Borrower shall have the right, upon five (5) Business Day's notice to
the Administrative Agent to either (x) cause a bank, reasonably acceptable to
the Administrative Agent, to offer to purchase the Commitments of such Bank for
an amount equal to such Bank's outstanding Loans, and to become a Bank
hereunder, or to obtain the agreement of one or more existing Banks to offer to
purchase the Commitments of such Bank for such amount, which offer such Bank is
hereby required to accept, or (y) to repay in full all Loans then outstanding of
such Bank, together with interest and all other amounts due thereon, upon which
event, such Bank's Commitment shall be deemed to be canceled pursuant to Section
2.11(c).

    SECTION 8.5. Base Rate Loans Substituted for Affected Euro-Dollar Loans. If
(i) the obligation of any Bank to make Euro-Dollar Loans has been suspended
pursuant to Section 8.2 or (ii) any Bank has demanded compensation under Section


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<PAGE>   69

8.3 or 8.4 with respect to its Euro-Dollar Loans and the Borrower shall, by at
least five Business Days' prior notice to such Bank through the Administrative
Agent, have elected that the provisions of this Section shall apply to such
Bank, then, unless and until such Bank notifies the Borrower that the
circumstances giving rise to such suspension or demand for compensation no
longer exist:

    (a) Borrower shall be deemed to have delivered a Notice of Interest Rate
Election with respect to such affected Euro-Dollar Loans and thereafter all
Loans which would otherwise be made by such Bank as Euro-Dollar Loans shall be
made instead as Base Rate Loans (on which interest and principal shall be
payable contemporaneously with the related Euro-Dollar Loans of the other
Banks), and

    (b) after each of its Euro-Dollar Loans has been repaid, all payments of
principal which would otherwise be applied to repay such Euro-Dollar Loans shall
be applied to repay its Base Rate Loans instead, and

    (c) Borrower will not be required to make any payment which would otherwise
be required by Section 2.13 with respect to such Euro-Dollar Loans converted to
Base Rate Loans pursuant to clause (a) above.


                                   ARTICLE IX

                                  MISCELLANEOUS

    SECTION 9.1. Notices. All notices, requests and other communications to any
party hereunder shall be in writing (including bank wire, telex, facsimile
transmission followed by telephonic confirmation or similar writing) and shall
be given to such party: (x) in the case of the Borrower, the Documentation
Agent, the Syndication Agent or the Administrative Agent, at its address, telex
number or facsimile number set forth on Exhibit F attached hereto with a
duplicate copy thereof, in the case of the Borrower, to the Borrower, at Equity
Office Properties Trust, Two North Riverside Plaza, Suite 2200, Chicago,
Illinois 60606, Attn: Chief Legal Counsel, and to Rosenberg & Liebentritt, P.C.,
Two North Riverside Plaza, Suite 1600, Chicago, Illinois 60606, Attn: James M.
Phipps, Esq., (y) in the case of any Bank, at its address, telex number or
facsimile number set forth in its Administrative Questionnaire or (z) in the
case of any party, such other address, telex number or facsimile number as such
party may hereafter specify for the purpose by notice to the Administrative
Agent and the Borrower. Each such notice, request or other communication shall
be effective (i) if given by telex or facsimile transmission, when such telex or
facsimile is transmitted to the telex number or facsimile number specified in
this Section and the appropriate answerback or facsimile confirmation is
received, (ii) if given by certified registered mail, return receipt requested,
with first class postage prepaid, addressed as aforesaid, upon receipt or
refusal to accept delivery, (iii) if given by a nationally recognized overnight
carrier, 24 hours after such communication is deposited with such carrier with
postage prepaid for next day delivery, or (iv) if given by any other means, when
delivered at the address specified in this Section; provided that notices to the
Administrative Agent and the Documentation Agent under Article II or Article
VIII shall not be effective until received.

    SECTION 9.2. No Waivers. No failure or delay by the Administrative Agent,
the Documentation Agent or any Bank in exercising any right, power or privilege



                                       65
<PAGE>   70

hereunder or under any Note 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, power or privilege. The rights and
remedies herein provided shall be cumulative and not exclusive of any rights or
remedies provided by law.

    SECTION 9.3. Expenses; Indemnification.

    (a) The Borrower shall pay within thirty (30) days after written notice from
the Administrative Agent or Documentation Agent, as applicable, (i) all
reasonable out-of-pocket costs and expenses of the Administrative Agent and the
Documentation Agent (including, without limitation, reasonable fees and
disbursements of special counsel Skadden, Arps, Slate, Meagher & Flom LLP ), in
connection with the preparation of this Agreement, the Loan Documents and the
documents and instruments referred to therein, and any waiver or consent
hereunder or any amendment hereof or any Default or alleged Default hereunder,
(ii) all reasonable fees and disbursements of special counsel in connection with
the syndication of the Loans, and (iii) if an Event of Default occurs, all
reasonable out-of-pocket expenses incurred by the Administrative Agent,
Documentation Agent and each Bank, including, without limitation, fees and
disbursements of counsel for the Administrative Agent, the Documentation Agent
and each of the Banks, in connection with the enforcement of the Loan Documents
and the instruments referred to therein and such Event of Default and
collection, bankruptcy, insolvency and other enforcement proceedings resulting
therefrom; provided, however, that the attorneys' fees and disbursements for
which Borrower is obligated under this subsection (a)(iii) shall be limited to
the reasonable non-duplicative fees and disbursements of (A) counsel for
Administrative Agent, (B) counsel for Documentation Agent and (C) counsel for
all of the Banks as a group; and provided, further, that all other costs and
expenses for which Borrower is obligated under this subsection (a)(iii) shall be
limited to the reasonable non-duplicative costs and expenses of Administrative
Agent and Documentation Agent. For purposes of this Section 9.3(a)(iii), (1)
counsel for Administrative Agent shall mean a single outside law firm
representing Administrative Agent, (2) counsel for Documentation Agent shall
mean a single outside law firm representing Documentation Agent (which may or
may not be the same law firm representing Administrative Agent) and (3) counsel
for all of the Banks as a group shall mean a single outside law firm
representing such Banks as a group (which law firm may or may not be the same
law firm representing either or both of Administrative Agent or Documentation
Agent).

    (b) The Borrower agrees to indemnify the Documentation Agent, the
Administrative Agent and each Bank, their respective affiliates and the
respective directors, officers, agents and employees of the foregoing (each an
"Indemnitee") and hold each Indemnitee harmless from and against any and all
liabilities, losses, damages, costs and expenses of any kind, including, without
limitation, the reasonable fees and disbursements of counsel, which may be
incurred by such Indemnitee in connection with any investigative, administrative
or judicial proceeding that may at any time (including, without limitation, at
any time following the payment of the Obligations) be asserted against any
Indemnitee, as a result of, or arising out of, or in any way related to or by
reason of, (i) any of the transactions contemplated by the Loan Documents or the
execution, delivery or performance of any Loan Document, (ii) any violation by
the Borrower or the Environmental Affiliates of any applicable Environmental
Law, (iii) any Environmental Claim arising out of the management, use, control,
ownership or operation of property or assets by the Borrower or any of the
Environmental Affiliates, including, without limitation, all on-site and







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<PAGE>   71

off-site activities of Borrower or any Environmental Affiliate involving
Materials of Environmental Concern, (iv) the breach of any environmental
representation or warranty set forth herein, but excluding those liabilities,
losses, damages, costs and expenses (a) for which such Indemnitee has been
compensated pursuant to the terms of this Agreement, (b) incurred solely by
reason of the gross negligence, willful misconduct bad faith or fraud of any
Indemnitee as finally determined by a court of competent jurisdiction, (c)
arising from violations of Environmental Laws relating to a Property which are
caused by the act or omission of such Indemnitee after such Indemnitee takes
possession of such Property or (d) owing by such Indemnitee to any third party
based upon contractual obligations of such Indemnitee owing to such third party
which are not expressly set forth in the Loan Documents. In addition, the
indemnification set forth in this Section 9.3(b) in favor of any director,
officer, agent or employee of Administrative Agent, Documentation Agent or any
Bank shall be solely in their respective capacities as such director, officer,
agent or employee. The Borrower's obligations under this Section shall survive
the termination of this Agreement and the payment of the Obligations. Without
limitation of the other provisions of this Section 9.3, Borrower shall indemnify
and hold each of the Administrative Agent, the Documentation Agent and the Banks
free and harmless from and against all loss, costs (including reasonable
attorneys' fees and expenses), expenses, taxes, and damages (including
consequential damages) that the Administrative Agent, the Documentation Agent
and the Banks may suffer or incur by reason of the investigation, defense and
settlement of claims and in obtaining any prohibited transaction exemption under
ERISA or the Code necessary in the Administrative Agent's or the Documentation
Agent's reasonable judgment by reason of the inaccuracy of the representations
and warranties, or a breach of the provisions, set forth in Section 4.6(b).

    SECTION 9.4. Sharing of Set-Offs. In addition to any rights now or hereafter
granted under applicable law or otherwise, and not by way of limitation of any
such rights, upon the occurrence and during the continuance of any Event of
Default, each Bank is hereby authorized at any time or from time to time,
without presentment, demand, protest or other notice of any kind to the Borrower
or to any other Person, any such notice being hereby expressly waived, but
subject to the prior consent of the Administrative Agent and the Documentation
Agent, to set off and to appropriate and apply any and all deposits (general or
special, time or demand, provisional or final) and any other indebtedness at any
time held or owing by such Bank (including, without limitation, by branches and
agencies of such Bank wherever located) to or for the credit or the account of
the Borrower against and on account of the Obligations of the Borrower then due
and payable to such Bank under this Agreement or under any of the other Loan
Documents, including, without limitation, all interests in Obligations purchased
by such Bank. Each Bank agrees that if it shall by exercising any right of
set-off or counterclaim or otherwise, receive payment of a proportion of the
aggregate amount of principal and interest due with respect to any Note held by
it which is greater than the proportion received by any other Bank, the Bank
receiving such proportionately greater payment shall purchase such
participations in the Notes held by the other Banks, and such other adjustments
shall be made, as may be required so that all such payments of principal and
interest with respect to the Notes held by the Banks shall be shared by the
Banks pro rata; provided that nothing in this Section shall impair the right of
any Bank to exercise any right of set-off or counterclaim it may have to any
deposits not received in connection with the Loans and to apply the amount
subject to such exercise to the payment of indebtedness of the Borrower other
than its indebtedness under the Notes. The Borrower agrees, to the fullest
extent it may effectively do so under applicable





                                       67
<PAGE>   72


law, that any holder of a participation in a Note, whether or not acquired
pursuant to the foregoing arrangements, may exercise rights of set-off or
counterclaim and other rights with respect to such participation as fully as if
such holder of a participation were a direct creditor of the Borrower in the
amount of such participation. Notwithstanding anything to the contrary contained
herein, any Bank may, by separate agreement with the Borrower, waive its right
to set off contained herein or granted by law and any such written waiver shall
be effective against such Bank under this Section 9.4.

    SECTION 9.5. Amendments and Waivers. Any provision of this Agreement or the
Notes or other Loan Documents may be amended or waived if, but only if, such
amendment or waiver is in writing and is signed by the Borrower and the Majority
Banks (and, if the rights or duties of the Administrative Agent , the
Documentation Agent or the Swingline Lender in their capacity as Administrative
Agent, Documentation Agent or the Swingline Lender, as applicable, are affected
thereby, by the Administrative Agent, the Documentation Agent or the Swingline
Lender, as applicable); provided that (A) no amendment or waiver of the
provisions of Article V (including, without limitation, any of the definitions
of the defined terms used in Section 5.8 hereof) shall be effective unless
signed by the Borrower and the Required Banks and (B) no such amendment or
waiver with respect to this Agreement, the Notes or any other Loan Documents
shall, unless signed by all the Banks, (i) increase or decrease the Commitment
of any Bank (except for a ratable decrease in the Commitments of all Banks) or
subject any Bank to any additional obligation, (ii) reduce the principal of or
rate of interest on any Loan or any fees hereunder, (iii) postpone the date
fixed for any payment of principal of or interest on any Loan or any fees
hereunder or for any reduction or termination of any Commitment, (iv) change the
percentage of the Commitments or of the aggregate unpaid principal amount of the
Notes, or the number of Banks, which shall be required for the Banks or any of
them to take any action under this Section or any other provision of this
Agreement, (v) release the EOPT Guaranty or (vi) modify the provisions of this
Section 9.5.

    SECTION 9.6. Successors and Assigns.

    (a) The provisions of this Agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective successors and assigns,
except that the Borrower may not assign or otherwise transfer any of its rights
under this Agreement or the other Loan Documents without the prior written
consent of all Banks and the Administrative Agent and a Bank may not assign or
otherwise transfer any of its interest under this Agreement except as permitted
in subsection (b) and (c) of this Section 9.6.

    (b) Prior to the occurrence of an Event of Default, any Bank may at any
time, with (and subject to) the consent of Borrower (which consent shall not be
unreasonably withheld or delayed) and the Administrative Agent, grant to an
existing Bank, one or more banks, finance companies, insurance companies or
other financial institutions (a "Participant") in minimum amounts of not less
than $10,000,000 (or any lesser amount in the case of participations to an
existing Bank) participating interests in its Commitment or any or all of its
Loans. After the occurrence and during the continuance of an Event of Default,
any Bank may at any time grant to any Person in any amount (also a
"Participant"), participating interests in its Commitment or any or all of its
Loans. Notwithstanding anything to the contrary in this subsection (b), with
respect to a Bank's granting of participations in its outstanding Money Market
Loans prior to the occurrence of an Event of Default, the minimum amount of such






                                       68
<PAGE>   73

participations shall be $5,000,000 and no consent of the Administrative Agent or
the Borrower shall be required. Any participation made during the continuation
of an Event of Default shall not be affected by the subsequent cure of such
Event of Default. In the event of any such grant by a Bank of a participating
interest to a Participant, whether or not upon notice to the Borrower and the
Administrative Agent, such Bank shall remain responsible for the performance of
its obligations hereunder, and the Borrower, the Documentation Agent and the
Administrative Agent shall continue to deal solely and directly with such Bank
in connection with such Bank's rights and obligations under this Agreement. Any
agreement pursuant to which any Bank may grant such a participating interest
shall provide that such Bank shall retain the sole right and responsibility to
enforce the obligations of the Borrower hereunder including, without limitation,
the right to approve any amendment, modification or waiver of any provision of
this Agreement; provided that such participation agreement may provide that such
Bank will not agree to any modification, amendment or waiver of this Agreement
described in clause (i), (ii), (iii), (iv) or (v) of Section 9.5 without the
consent of the Participant. The Borrower agrees that each Participant shall, to
the extent provided in its participation agreement, be entitled to the benefits
of Article VIII with respect to its participating interest.

    (c) Any Bank may at any time assign to a Qualified Institution (in each
case, an "Assignee") (i) prior to the occurrence of an Event of Default, in
minimum amounts of not less than Ten Million Dollars ($10,000,000) and integral
multiple of One Million Dollars ($1,000,000) thereafter (or any lesser amount in
the case of assignments to an existing Bank) and (ii) after the occurrence and
during the continuance of an Event of Default, in any amount, all or a
proportionate part of all, of its rights and obligations under this Agreement,
the Notes and the other Loan Documents, and, in either case, such Assignee shall
assume such rights and obligations, pursuant to a Transfer Supplement in
substantially the form of Exhibit "E" hereto executed by such Assignee and such
transferor Bank; provided, that if no Event of Default shall have occurred and
be continuing, such assignment shall be subject to the Administrative Agent's
and the Borrower's consent, which consent shall not be unreasonably withheld or
delayed; and provided further that if an Assignee is an affiliate of such
transferor Bank or was a Bank immediately prior to such assignment, no such
consent shall be required; and provided further that such assignment may, but
need not, include rights of the transferor Bank in respect of outstanding Money
Market Loans. Upon execution and delivery of such instrument and payment by such
Assignee to such transferor Bank of an amount equal to the purchase price agreed
between such transferor Bank and such Assignee, such Assignee shall be a Bank
party to this Agreement and shall have all the rights and obligations of a Bank
with a Commitment as set forth in such instrument of assumption, and no further
consent or action by any party shall be required and the transferor Bank shall
be released from its obligations hereunder to a corresponding extent. Upon the
consummation of any assignment pursuant to this subsection (c), the transferor
Bank, the Administrative Agent and the Borrower shall make appropriate
arrangements so that, if required, a new Note is issued to the Assignee. In
connection with any such assignment, the transferor Bank shall pay to the
Administrative Agent an administrative fee for processing such assignment in the
amount of $2,500. If the Assignee is not incorporated under the laws of the
United States of America or a state thereof, it shall deliver to the Borrower
and the Administrative Agent certification as to exemption from deduction or
withholding of any United States federal income taxes in accordance with Section
8.4.



                                       69
<PAGE>   74

Any assignment made during the continuation of an Event of Default shall not be
affected by any subsequent cure of such Event of Default.

    (d) Any Bank (each, a "Designating Lender") may at any time designate one
Designated Lender to fund Money Market Loans on behalf of such Designating
Lender subject to the terms of this Section 9.6(d) and the provisions in Section
9.6(b) and (c) shall not apply to such designation. No Bank may designate more
than one (1) Designated Lender at any one time. The parties to each such
designation shall execute and deliver to the Lead Agent for its acceptance a
Designation Agreement. Upon such receipt of an appropriately completed
Designation Agreement executed by a Designating Lender and a designee
representing that it is a Designated Lender, the Lead Agent will accept such
Designation Agreement and will give prompt notice thereof to the Borrower,
whereupon, (i) the Borrower shall execute and deliver to the Designating Lender
a Designated Lender Note payable to the order of the Designated Lender, (ii)
from and after the effective date specified in the Designation Agreement, the
Designated Lender shall become a party to this Agreement with a right (subject
to the provisions of Section 2.4(b)) to make Money Market Loans on behalf of its
Designating Lender pursuant to Section 2.4 after the Borrower has accepted a
Money Market Loan (or portion thereof) of the Designating Lender, and (iii) the
Designated Lender shall not be required to make payments with respect to any
obligations in this Agreement except to the extent of excess cash flow of such
Designated Lender which is not otherwise required to repay obligations of such
Designated Lender which are then due and payable; provided, however, that
regardless of such designation and assumption by the Designated Lender, the
Designating Lender shall be and remain obligated to the Borrower, the
Administrative Agent, the Managing Agents, the Co-Agents and the Banks for each
and every of the obligations of the Designating Lender and its related
Designated Lender with respect to this Agreement, including, without limitation,
any indemnification obligations under Section 7.6 hereof and any sums otherwise
payable to the Borrower by the Designated Lender. Each Designating Lender shall
serve as the administrative agent of the Designated Lender and shall on behalf
of, and to the exclusion of, the Designated Lender: (i) receive any and all
payments made for the benefit of the Designated Lender and (ii) give and receive
all communications and notices and take all actions hereunder, including,
without limitation, votes, approvals, waivers, consents and amendments under or
relating to this Agreement and the other Loan Documents. Any such notice,
communication, vote, approval, waiver, consent or amendment shall be signed by
the Designating Lender as administrative agent for the Designated Lender and
shall not be signed by the Designated Lender on its own behalf and shall be
binding upon the Designated Lender to the same extent as if signed by the
Designated Lender on its own behalf. The Borrower, the Administrative Agent, the
Managing Agents, the Co-Agents and the Banks may rely thereon without any
requirement that the Designated Lender sign or acknowledge the same. No
Designated Lender may assign or transfer all or any portion of its interest
hereunder or under any other Loan Document, other than assignments to the
Designating Lender which originally designated such Designated Lender or
otherwise in accordance with the provisions of Section 9.6 (b) and (c).

    (e) Any Bank may at any time assign all or any portion of its rights under
this Agreement and its Note to a Federal Reserve Bank. No such assignment shall
release the transferor Bank from its obligations hereunder.

    (f) No Assignee, Participant or other transferee of any Bank's rights shall
be entitled to receive any greater payment under Section 8.3 or 8.4 than such
Bank would have been entitled to receive with respect to the rights transferred,
unless such transfer is made with the Borrower's prior written consent or by



                                       70
<PAGE>   75

reason of the provisions of Section 8.2, 8.3 or 8.4 requiring such Bank to
designate a different Applicable Lending Office under certain circumstances or
at a time when the circumstances giving rise to such greater payment did not
exist.

    (g) No Assignee of any rights and obligations under this Agreement shall be
permitted to further assign less than all of such rights and obligations. No
participant in any rights and obligations under this Agreement shall be
permitted to sell subparticipations of such rights and obligations.

    (h) Anything in this Agreement to the contrary notwithstanding, so long as
no Event of Default shall have occurred and be continuing, no Bank shall be
permitted to enter into an assignment of, or sell a participation interest in,
its rights and obligations hereunder which would result in such Bank holding a
Commitment without participants of less than Ten Million Dollars ($10,000,000)
(or in the case of the Administrative Agent, Documentation Agent or Morgan
Guaranty Trust Company of New York or the Managing Agents, Thirty Million
Dollars ($30,000,000), or in the case of any Co-Agent, Twenty Million Dollars
($20,000,000)) unless as a result of a cancellation or reduction of the
aggregate Commitments; provided, however, that no Bank shall be prohibited from
assigning its entire Commitment so long as such assignment is otherwise
permitted under this Section 9.6.

    (i) By its execution of this Agreement, each of the Banks which were parties
to the Existing Credit Agreement (each an "Existing Bank") hereby assigns and
sells to the Banks accepting the same as set forth below, without recourse,
representation or warranty (except as expressly provided herein), that portion
of its "Commitment" under the Existing Loan Agreement which is in excess of its
Commitment hereunder. By its execution of this Agreement, each of the Banks
which were not parties to the Existing Credit Agreement (each a "New Bank") and
each Existing Bank whose Commitment hereunder exceeds its "Commitment" under the
Existing Credit Agreement hereby accepts the portion of the above-referenced
excess "Commitments" which is equal to the (i) in the case of a New Bank, the
amount of its Commitment hereunder, and (ii) in the case of an Existing Bank
whose Commitment hereunder exceeds its "Commitment" under the Existing Credit
Agreement, the amount of such increase. Each Bank hereby acknowledges and agrees
that, as of the date hereof, its Commitment hereunder is in the amount shown on
the signature page of such Bank attached to this Agreement. Each Existing Bank
hereby represents and warrants that it is the legal and beneficial owner of the
interests being assigned by it in accordance with this Section 9.6(f) and that
such interests are free and clear of any adverse claim.

    SECTION 9.7. Collateral. Each of the Banks represents to the Administrative
Agent and each of the other Banks that it in good faith is not relying upon any
"margin stock" (as defined in Regulation U) as collateral in the extension or
maintenance of the credit provided for in this Agreement.

    SECTION 9.8. Governing Law; Submission to Jurisdiction. (a) THIS AGREEMENT
AND THE OTHER LOAN DOCUMENTS AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER AND THEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND BE GOVERNED
BY THE LAWS OF THE STATE OF ILLINOIS (WITHOUT GIVING EFFECT TO THE PRINCIPLES
THEREOF RELATING TO CONFLICTS OF LAW).



                                       71
<PAGE>   76

    (b) Any legal action or proceeding with respect to this Agreement or any
other Loan Document and any action for enforcement of any judgment in respect
thereof may be brought in the courts of the State of Illinois or of the United
States of America for the Northern District of Illinois, and, by execution and
delivery of this Agreement, the Borrower hereby accepts for itself and in
respect of its property, generally and unconditionally, the non-exclusive
jurisdiction of the aforesaid courts and appellate courts from any thereof. The
Borrower irrevocably consents to the service of process out of any of the
aforementioned courts in any such action or proceeding by the hand delivery, or
mailing of copies thereof by registered or certified mail, postage prepaid, to
the Borrower at its address set forth below. The Borrower hereby irrevocably
waives any objection which it may now or hereafter have to the laying of venue
of any of the aforesaid actions or proceedings arising out of or in connection
with this Agreement or any other Loan Document brought in the courts referred to
above and hereby further irrevocably waives and agrees not to plead or claim in
any such court that any such action or proceeding brought in any such court has
been brought in an inconvenient forum. Nothing herein shall affect the right of
the Administrative Agent or the Documentation Agent to serve process in any
other manner permitted by law or to commence legal proceedings or otherwise
proceed against the Borrower in any other jurisdiction.

    SECTION 9.9. Counterparts; Integration;. Effectiveness. This Agreement may
be signed in any number of counterparts, each of which shall be an original,
with the same effect as if the signatures thereto and hereto were upon the same
instrument. This Agreement constitutes the entire agreement and understanding
among the parties hereto and supersedes any and all prior agreements and
understandings, oral or written, relating to the subject matter hereof. This
Agreement shall become effective upon receipt by the Documentation Agent and the
Borrower of counterparts hereof signed by each of the parties hereto (or, in the
case of any party as to which an executed counterpart shall not have been
received, receipt by the Administrative Agent in form satisfactory to it of
telegraphic, telex or other written confirmation from such party of execution of
a counterpart hereof by such party).

    SECTION 9.10. WAIVER OF JURY TRIAL. EACH OF THE BORROWER, THE ADMINISTRATIVE
AGENT, THE DOCUMENTATION AGENT, THE SYNDICATION AGENT AND THE BANKS HEREBY
IRREVOCABLY WAIVE ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING
ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED
HEREBY.

    SECTION 9.11. Survival. All indemnities set forth herein shall survive the
execution and delivery of this Agreement and the other Loan Documents and the
making and repayment of the Loans hereunder.

    SECTION 9.12. Domicile of Loans. Each Bank may transfer and carry its Loans
at, to or for the account of any domestic or foreign branch office, subsidiary
or affiliate of such Bank.

    SECTION 9.13. Limitation of Liability. No claim may be made by the Borrower
or any other Person acting by or through Borrower against the Administrative
Agent, the Documentation Agent, the Syndication Agent or any Bank or the
affiliates, directors, officers, employees, attorneys or agent of any of them
for any punitive damages in respect of any claim for breach of contract or any
other theory of liability arising out of or related to the transactions
contemplated by this Agreement or by the other Loan Documents, or any act,
omission or event occurring in connection therewith; and the Borrower hereby



                                       72
<PAGE>   77

waives, releases and agrees not to sue upon any claim for any such damages,
whether or not accrued and whether or not known or suspected to exist in its
favor.

    SECTION 9.14. Recourse Obligation. This Agreement and the Obligations
hereunder are fully recourse to the Borrower. Notwithstanding the foregoing, no
recourse under or upon any obligation, covenant, or agreement contained in this
Agreement shall be had against (i) any officer, director, shareholder or
employee of the Borrower or EOPT (other than pursuant to the Acorn Guaranty (as
defined in the EOPT Guaranty)) or (ii) any general partner of Borrower other
than EOPT, in each case except in the event of fraud or misappropriation of
funds on the part of such officer, director, shareholder or employee or such
general partner.

    SECTION 9.15. Confidentiality. The Administrative Agent, the Documentation
Agent and each Bank shall use reasonable efforts to assure that information
about Borrower, EOPT and its Subsidiaries and Investments Affiliates, and the
Properties thereof and their operations, affairs and financial condition, not
generally disclosed to the public, which is furnished to Administrative Agent,
the Documentation Agent or any Bank pursuant to the provisions hereof or any
other Loan Document is used only for the purposes of this Agreement and shall
not be divulged to any Person other than the Administrative Agent, the
Documentation Agent, the Banks, and their affiliates and respective officers,
directors, employees and agents who are actively and directly participating in
the evaluation, administration or enforcement of the Loan and other transactions
between such Bank and the Borrower, except: (a) to their attorneys and
accountants, (b) in connection with the enforcement of the rights and exercise
of any remedies of the Administrative Agent, the Documentation Agent and the
Banks hereunder and under the other Loan Documents, (c) in connection with
assignments and participations and the solicitation of prospective assignees and
participants referred to in Section 9.6 hereof, who have agreed in writing to be
bound by a confidentiality agreement substantially equivalent to the terms of
this Section 9.15, and (d) as may otherwise be required or requested by any
regulatory authority having jurisdiction over the Administrative Agent, the
Documentation Agent or any Bank or by any applicable law, rule, regulation or
judicial process.

    SECTION 9.16. Bank's Failure to Fund.

    (a) If a Bank does not advance to Administrative Agent such Bank's Pro Rata
Share of a Loan in accordance herewith, then neither Administrative Agent,
Documentation Agent nor the other Banks shall be required or obligated to fund
such Bank's Pro Rata Share of such Loan.

    (b) As used herein, the following terms shall have the meanings set forth
below:

         (i) "Defaulting Bank" shall mean any Bank which (x) does not advance to
the Administrative Agent such Bank's Pro Rata Share of a Loan in accordance
herewith for a period of five (5) Business Days after notice of such failure
from Administrative Agent, (y) shall otherwise fail to perform such Bank's
obligations under the Loan Documents (including, without limitation, the
obligation to purchase participations pursuant to Section 2.3) for a period of
five (5) Business Days after notice of such failure from Administrative Agent,
or (z) shall fail to pay the Administrative Agent, Documentation Agent or any
other Bank, as the case may be, upon demand, such Bank's Pro Rata Share of any


                                       73
<PAGE>   78

costs, expenses or disbursements incurred or made by the Administrative Agent
pursuant to the terms of the Loan Documents for a period of five (5) Business
Days after notice of such failure from Administrative Agent, and in all cases,
such failure is not as a result of a good faith dispute as to whether such
advance is properly required to be made pursuant to the provisions of this
Agreement, or as to whether such other performance or payment is properly
required pursuant to the provisions of this Agreement.

         (ii) "Junior Creditor" means any Defaulting Bank which has not (x)
fully cured each and every default on its part under the Loan Documents and (y)
unconditionally tendered to the Administrative Agent such Defaulting Bank's Pro
Rata Share of all costs, expenses and disbursements required to be paid or
reimbursed pursuant to the terms of the Loan Documents.

         (iii) "Payment in Full" means, as of any date, the receipt by the Banks
who are not Junior Creditors of an amount of cash, in lawful currency of the
United States, sufficient to indefeasibly pay in full all Senior Debt.

         (iv) "Senior Debt" means (x) collectively, any and all indebtedness,
obligations and liabilities of the Borrower to the Banks who are not Junior
Creditors from time to time, whether fixed or contingent, direct or indirect,
joint or several, due or not due, liquidated or unliquidated, determined or
undetermined, arising by contract, operation of law or otherwise, whether on
open account or evidenced by one or more instruments, and whether for principal,
premium, interest (including, without limitation, interest accruing after the
filing of a petition initiating any proceeding referred to in Section 6.1(f) or
(g)), reimbursement for fees, indemnities, costs, expenses or otherwise, which
arise under, in connection with or in respect of the Loans or the Loan
Documents, and (y) any and all deferrals, renewals, extensions and refundings
of, or amendments, restatements, rearrangements, modifications or supplements
to, any such indebtedness, obligation or liability.

         (v) "Subordinated Debt" means (x) any and all indebtedness, obligations
and liabilities of Borrower to one or more Junior Creditors from time to time,
whether fixed or contingent, direct or indirect, joint or several, due or not
due, liquidated or unliquidated, determined or undetermined, arising by
contract, operation of law or otherwise, whether on open account or evidenced by
one or more instruments, and whether for principal, premium, interest
(including, without limitation, interest accruing after the filing of a petition
initiating any proceeding referred to in Section 6.1(f) or (g)), reimbursement
for fees, indemnities, costs, expenses or otherwise, which arise under, in
connection with or in respect of the Loans or the Loan Documents, and (y) any
and all deferrals, renewals, extensions and refundings of, or amendments,
restatements, rearrangements, modifications or supplements to, any such
indebtedness, obligation or liability.

    (c) Immediately upon a Bank's becoming a Junior Creditor and until such time
as such Bank shall have cured all applicable defaults, no Junior Creditor shall,
prior to Payment in Full of all Senior Debt:

         (i) accelerate, demand payment of, sue upon, collect, or receive any
payment upon, in any manner, or satisfy or otherwise discharge, any Subordinated
Debt, whether for principal, interest and otherwise;

         (ii) take or enforce any Liens to secure Subordinated Debt or attach or
levy upon any assets of Borrower, to enforce any Subordinated Debt;



                                       74
<PAGE>   79

         (iii) enforce or apply any security for any Subordinated Debt; or

         (iv) incur any debt or liability, or the like, to, or receive any loan,
return of capital, advance, gift or any other property, from, the Borrower.

    (d) In the event of:

         (i) any insolvency, bankruptcy, receivership, liquidation,
dissolution, reorganization, readjustment, composition or other similar
proceeding relating to Borrower;

         (ii) any liquidation, dissolution or other winding-up of the Borrower,
voluntary or involuntary, whether or not involving insolvency, reorganization or
bankruptcy proceedings;

         (iii) any assignment by the Borrower for the benefit of creditors;

         (iv) any sale or other transfer of all or substantially all assets of
the Borrower; or

         (v) any other marshaling of the assets of the Borrower;

each of the Banks shall first have received Payment in Full of all Senior Debt
before any payment or distribution, whether in cash, securities or other
property, shall be made in respect of or upon any Subordinated Debt. Any payment
or distribution, whether in cash, securities or other property that would
otherwise be payable or deliverable in respect of Subordinated Debt to any
Junior Creditor but for this Agreement shall be paid or delivered directly to
the Administrative Agent for distribution to the Banks in accordance with this
Agreement until Payment in Full of all Senior Debt. If any Junior Creditor
receives any such payment or distribution, it shall promptly pay over or deliver
the same to the Administrative Agent for application in accordance with the
preceding sentence.

    (e) Each Junior Creditor shall file in any bankruptcy or other proceeding of
Borrower in which the filing of claims is required by law, all claims relating
to Subordinated Debt that such Junior Creditor may have against Borrower and
assign to the Banks who are not Junior Creditors all rights of such Junior
Creditor thereunder. If such Junior Creditor does not file any such claim prior
to forty-five (45) days before the expiration of the time to file such claim,
Administrative Agent, as attorney-in-fact for such Junior Creditor, is hereby
irrevocably authorized to do so in the name of such Junior Creditor or, in
Administrative Agent's sole discretion, to assign the claim to a nominee and to
cause proof of claim to be filed in the name of such nominee. The foregoing
power of attorney is coupled with an interest and cannot be revoked. The
Administrative Agent shall, to the exclusion of each Junior Creditor, have the
sole right, subject to Section 9.5 hereof, to accept or reject any plan proposed
in any such proceeding and to take any other action that a party filing a claim
is entitled to take. In all such cases, whether in administration, bankruptcy or
otherwise, the Person or Persons authorized to pay such claim shall pay to
Administrative Agent the amount payable on such claim and, to the full extent
necessary for that purpose, each Junior Creditor hereby transfers and assigns to
the Administrative Agent all of the Junior Creditor's rights to any such
payments or distributions to which Junior Creditor would otherwise be entitled.



                                       75
<PAGE>   80

    (f) (i) If any payment or distribution of any character or any security,
whether in cash, securities or other property, shall be received by any Junior
Creditor in contravention of any of the terms hereof, such payment or
distribution or security shall be received in trust for the benefit of, and
shall promptly be paid over or delivered and transferred to, Administrative
Agent for application to the payment of all Senior Debt, to the extent necessary
to achieve Payment in Full. In the event of the failure of any Junior Creditor
to endorse or assign any such payment, distribution or security, Administrative
Agent is hereby irrevocably authorized to endorse or assign the same as
attorney-in-fact for such Junior Creditor.

         (ii) Each Junior Creditor shall take such action (including, without
limitation, the execution and filing of a financing statement with respect to
this Agreement and the execution, verification, delivery and filing of proofs of
claim, consents, assignments or other instructions that Administrative Agent may
require from time to time in order to prove or realize upon any rights or claims
pertaining to Subordinated Debt or to effectuate the full benefit of the
subordination contained herein) as may, in Administrative Agent's sole and
absolute discretion, be necessary or desirable to assure the effectiveness of
the subordination effected by this Agreement.

    (g) (i) Each Bank that becomes a Junior Creditor understands and
acknowledges by its execution hereof that each other Bank is entering into this
Agreement and the Loan Documents in reliance upon the absolute subordination in
right of payment and in time of payment of Subordinated Debt to Senior Debt as
set forth herein.

         (ii) Only upon the Payment in Full of all Senior Debt shall any Junior
Creditor be subrogated to any remaining rights of the Banks which are not
Defaulting Banks to receive payments or distributions of assets of the Borrower
made on or applicable to any Senior Debt.

         (iii) Each Junior Creditor agrees that it will deliver all instruments
or other writings evidencing any Subordinated Debt held by it to Administrative
Agent, promptly after request therefor by the Administrative Agent.

         (iv) No Junior Creditor may at any time sell, assign or otherwise
transfer any Subordinated Debt, or any portion thereof, including, without
limitation, the granting of any Lien thereon, unless and until satisfaction of
the requirements of Section 9.6 above and the proposed transferee shall have
assumed in writing the obligation of the Junior Creditor to the Banks under this
Agreement, in a form acceptable to the Administrative Agent.

         (v) If any of the Senior Debt, should be invalidated, avoided or set
aside, the subordination provided for herein nevertheless shall continue in full
force and effect and, as between the Banks which are not Defaulting Banks and
all Junior Creditors, shall be and be deemed to remain in full force and effect.

         (vi) Each Junior Creditor hereby irrevocably waives, in respect of
Subordinated Debt, all rights (x) under Sections 361 through 365, 502(e) and 509
of the Bankruptcy Code (or any similar sections hereafter in effect under any
other Federal or state laws or legal or equitable principles relating to
bankruptcy, insolvency, reorganizations, liquidations or otherwise for the
relief of debtors or protection of creditors), and (y) to seek or obtain
conversion to a different type of proceeding or to seek or obtain dismissal of a
proceeding, in each case in relation to a bankruptcy, reorganization, insolvency
or other proceeding under similar laws




                                       76
<PAGE>   81


with respect to the Borrower. Without limiting the generality of the foregoing,
each Junior Creditor hereby specifically waives (A) the right to seek to give
credit (secured or otherwise) to the Borrower in any way under Section 364 of
the Bankruptcy Code unless the same is subordinated in all respects to Senior
Debt in a manner acceptable to Administrative Agent in its sole and absolute
discretion and (B) the right to receive any collateral security (including,
without limitation, any "super priority" or equal or "priming" or replacement
Lien) for any Subordinated Debt unless the Banks which are not Defaulting Banks
have received a senior position acceptable to the Banks in their sole and
absolute discretion to secure all Senior Debt (in the same collateral to the
extent collateral is involved).

    (h) (i) In addition to and not in limitation of the subordination effected
by this Section 9.16, the Administrative Agent and each of the Banks which are
not Defaulting Banks may in their respective sole and absolute discretion, also
exercise any and all other rights and remedies available at law or in equity in
respect of a Defaulting Bank; and

         (ii) The Administrative Agent shall give each of the Banks notice of
the occurrence of a default under this Section 9.16 by a Defaulting Bank and if
the Administrative Agent and/or one or more of the other Banks shall, at their
option, fund any amounts required to be paid or advanced by a Defaulting Bank,
the other Banks who have elected not to fund any portion of such amounts shall
not be liable for any reimbursements to the Administrative Agent and/or to such
other funding Banks.

    (i) Notwithstanding anything to the contrary contained or implied herein, a
Defaulting Bank shall not be entitled to vote on any matter as to which a vote
by the Banks is required hereunder, including, without limitation, any actions
or consents on the part of the Administrative Agent as to which the approval or
consent of all the Banks or the Required Banks or Majority Banks is required
under Article VIII, Section 9.5 or elsewhere, so long as such Bank is a
Defaulting Bank; provided, however, that in the case of any vote requiring the
unanimous consent of the Banks, if all the Banks other than the Defaulting Bank
shall have voted in accordance with each other, then the Defaulting Bank shall
be deemed to have voted in accordance with such Banks.

    (j) Each of the Administrative Agent and any one or more of the Banks which
are not Defaulting Banks may, at their respective option, (i) advance to the
Borrower such Bank's Pro Rata Share of the Loans not advanced by a Defaulting
Bank in accordance with the Loan Documents, or (ii) pay to the Administrative
Agent such Bank's Pro Rata Share of any costs, expenses or disbursements
incurred or made by the Administrative Agent pursuant to the terms of this
Agreement not theretofore paid by a Defaulting Bank. Immediately upon the making
of any such advance by the Administrative Agent or any one of the Banks, such
Bank's Pro Rata Share and the Pro Rata Share of the Defaulting Bank shall be
recalculated to reflect such advance. All payments, repayments and other
disbursements of funds by the Administrative Agent to Banks shall thereupon and,
at all times thereafter be made in accordance with such Bank's recalculated Pro
Rata Share unless and until a Defaulting Bank shall fully cure all defaults on
the part of such Defaulting Bank under the Loan Documents or otherwise existing
in respect of the Loans or this Agreement, at which time the Pro Rata Share of
the Bank(s) which advanced sums on behalf of the Defaulting Bank and of the
Defaulting Bank shall be restored to their original percentages.



                                       77
<PAGE>   82

    SECTION 9.17. Banks' ERISA Covenant. Each Bank, by its signature hereto or
on the applicable Transfer Supplement, hereby agrees (a) that on the date any
Loan is disbursed hereunder no portion of such Bank's Pro Rata Share of such
Loan will constitute "assets" within the meaning of 29 C.F.R. Section 2510.3-101
of an "employee benefit plan" within the meaning of Section 3(3) of ERISA or a
"plan" within the meaning of Section 4975(e)(1) of the Code, and (b) that
following such date such Bank shall not allocate such Bank's Pro Rata Share of
any Loan to an account of such Bank if such allocation (i) by itself would cause
such Pro Rata Share of such Loan to then constitute "assets" (within the meaning
of 29 C.F.R. Section 2510.3-101) of an "employee benefit plan" within the
meaning of Section 3(3) of ERISA or a "plan" within the meaning of Section
4975(e)(1) of the Code and (ii) by itself would cause such Loan to constitute a
prohibited transaction under ERISA or the Code (which is not exempt from the
restrictions of Section 406 of ERISA and Section 4975 of the Code and the taxes
and penalties imposed by Section 4975 of the Code and Section 502(i) of ERISA)
or any Agent or Bank being deemed in violation of Section 404 of ERISA.

    SECTION 9.18. Managing Agents and Co-Agents. Borrower, the Agents and each
Bank acknowledges and agrees that the obligations of the Managing Agents and the
Co-Agents hereunder shall be limited to those obligations that are expressly set
forth herein, if any, and the Managing Agents and the Co-Agents shall not be
required to take any action or assume any liability except as may be required in
each of their capacity as a Bank hereunder. Borrower, the Agents and each Bank
agrees that the indemnifications set forth herein for the benefit of the Agents
shall also run to the benefit of the Managing Agents and the Co-Agents to the
extent the Managing Agents and/or any Agent incurs any loss, cost or damage
arising from its capacity as the Managing Agents or as a Co-Agent.

    SECTION 9.19. No Bankruptcy Proceedings. Each of the Borrower, the Banks,
the Administrative Agent, the Managing Agents, and the Co-Agents hereby agrees
that it will not institute against any Designated Lender or join any other
Person in instituting against any Designated Lender any bankruptcy,
reorganization, arrangement, insolvency or liquidation proceeding under any
federal or state bankruptcy or similar law, until the later to occur of (i) one
year and one day after the payment in full of the latest maturing commercial
paper note issued by such Designated Lender and (ii) the Maturity Date.

                            [SIGNATURE PAGE FOLLOWS]

    IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed by their respective authorized officers as of the day and year first
above written.


                           EOP OPERATING LIMITED PARTNERSHIP,
                           a Delaware limited partnership

                   By:     Equity Office Properties Trust, a Maryland real
                                estate investment trust, its managing general
                                partner


                   By:
                           Name:
                           Title:

                   Facsimile number: (312) 559-5009
                   Address:     Two North Riverside Plaza
                                Suite 2200
                                Chicago, Illinois 60606
                                Attn: Chief Financial Officer




                                       78
<PAGE>   83

TOTAL COMMITMENTS:         $1,000,000,000
                           NATIONSBANK, N.A., as Administrative Agent,
                           as Swingline Lender and as a Bank


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

                   Commitment: $69,000,000
                           BANK OF AMERICA, NATIONAL TRUST &
                           SAVINGS ASSOCIATION, as Documentation
                           Agent and as a Bank


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

                   Commitment: $69,000,000
                           J.P. MORGAN SECURITIES, INC., as Syndication
                           Agent


                   By:
                      --------------------------------------------

                   Name:
                   Title:

                           MORGAN GUARANTY TRUST COMPANY OF
                           NEW YORK, as a Bank


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

                   Commitment: $69,000,000
                           THE BANK OF NOVA SCOTIA, as a Managing
                           Agent and as a Bank


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


                   Commitment: $65,000,000

                         THE CHASE MANHATTAN BANK, as a
                          Managing Agent and as a Bank


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




<PAGE>   84

                   Commitment: $65,000,000

                   COMMERZBANK AKTIENGESELLSCHAFT, as a


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

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


                   Commitment: $65,000,000


                         DRESDNER BANK AG, NEW YORK AND
                           CAYMAN BRANCHES, as a Managing Agent and
                           as Bank


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

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


                   Commitment: $65,000,000

                           PNC BANK, NATIONAL ASSOCIATION, as a
                          Managing Agent and as a Bank


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

                   Commitment: $65,000,000
                         UNION BANK OF SWITZERLAND, NEW
                           YORK BRANCH, as a Managing Agent and as a
                           Bank


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




<PAGE>   85


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



                   Commitment: $65,000,000
                           CREDIT LYONNAIS, NEW YORK BRANCH, as
                           a Co-Agent and as a Bank


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

                   Commitment: $54,000,000
                           FLEET NATIONAL BANK, as a Co-Agent and as
                           a Bank


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

                   Commitment: $54,000,000
                           U.S. BANK NATIONAL ASSOCIATION, as a
                           Co-Agent and as a Bank


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

                   Commitment: $54,000,000

                           BANK ONE, ILLINOIS, N.A., as a Bank


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

                   Commitment: $50,000,000

                           BAYERISCHE HYPOTHEKEN-UND
                           WECHSEL-BANK AKTIENGESELLSCHAFT, as a
                           Bank


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

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

<PAGE>   86


                   Commitment: $50,000,000
                           BANKBOSTON, N.A., as a Bank


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

                   Commitment: $31,000,000

                           LASALLE NATIONAL BANK, as a Bank


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

                   Commitment: $30,000,000
                             MELLON BANK, as a Bank


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

                   Commitment: $30,000,000
                           UNION BANK OF CALIFORNIA, N.A., as a Bank


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

                   Commitment: $30,000,000

                           THE INDUSTRIAL BANK OF JAPAN,
                           LIMITED, as a Bank


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

                   Commitment: $20,000,000


<PAGE>   87

                                  Schedule 1.1
                   Initial Qualifying Unencumbered Properties

<TABLE>
<CAPTION>

      Property Name                                           Location
      -------------                                           --------
<S>                                                        <C>
1,2,3 Devon Square                                         Wayne, PA

1-5 Valley Square                                          Plymouth Meeting, PA

10/30 S. Wacker                                            Chicago, IL

1100 Executive Tower                                       Orange County,  CA

1111 19th Street                                           Washington, D.C.

1601 Market Street                                         Philadelphia, PA

1620 L Street                                              Washington, D.C.

1700 Market                                                Philadelphia, PA

177 Broad                                                  Stamford, CT

1920 Main Plaza                                            Orange County, CA

201 Mission                                                San Francisco, CA

2010 Main Plaza                                            Orange County, CA

28 State Street                                            Boston, MA

30 North LaSalle                                           Chicago,IL

300 Atlantic Street                                        Stamford, CT

49 East Thomas                                             Phoenix, AZ

500 Marquette Building                                     Albuquerque, NM

500 Orange Tower                                           Orange County, CA

5100 Brookline                                             Oklahoma City, OK

550 South Hope                                             Los Angeles, CA

60 Spear Street Building                                   San Francisco, CA

601 Tehoupitoulas                                          New Orleans, LA

8080 Central                                               Dallas, TX

850 Third Avenue                                           New York, NY

9400 NCX                                                   Dallas, TX

Adams/Wabash Garage                                        Chicago, IL

Atrium Towers                                              Oklahoma City, OK

Bank One Center/Tower                                      Indianapolis, IN
</TABLE>




<PAGE>   88

<TABLE>

<S>                                                    <C>
Brookhollow I, II, III                                     Houston, TX

Civic Parking                                              St. Louis, MO

Colonnade I                                                San Antonio, TX

Denver Corporate Center II & III                           Denver, CO

Destec Tower                                               Houston, TX

Dominion Tower                                             Norfolk, VA

First Union Center                                         Ft. Lauderdale, FL

Four Falls                                                 West Conshohocken, PA

Four Forest                                                Dallas, TX

Intercontinental Center                                    Houston, TX

LL & E Tower                                               New Orleans, LA

Nations Bank Plaza                                         Nashville, TN

North Central Plaza Three                                  Dallas, TX

Northborough Tower                                         Houston, TX

Oak Hill Plaza                                             King of Prussia, PA

Oakbrook Terrace                                           Oak Brook Terrace, IL

One American Center                                        Austin, TX

One Clearlake Centre                                       West Palm Beach, FL

One Layfayette                                             Washington, D.C.

One Maritime Plaza                                         San Francisco, CA

One North Franklin                                         Chicago, IL

One Phoenix                                                Phoenix, AZ

One & Two Stamford Plaza                                   Stamford, CT

Paces West                                                 Atlanta, GA

Philadelphia Garages                                       Philadelphia, PA

Preston Commons                                            Dallas, TX

San Jacinto Center                                         Austin, TX

Sarasota City Center                                       Sarasota, FL
</TABLE>


<PAGE>   89

<TABLE>

<S>                                                    <C>
Shelton Point                                              Shelton, CT

Smith Barney                                               San Diego, CA

Sterling Plaza                                             Dallas, TX

Summitt Office Park                                        Ft. Worth, TX

Sun Trust Building                                         Orlando, FL

Tampa Commons                                              Tampa, FL

Texaco Center                                              New Orleans, LA

The Quadrant                                               Denver, CO

Two California Plaza                                       Los Angeles, CA

Union Square                                               San Antonio, TX

University Tower                                           Durham, NC
</TABLE>



<PAGE>   90


                                 SCHEDULE 4.4(b)

                                  Disclosure of
                        Additional Material Indebtedness


1.  Drawings under this Agreement.

2.  On April 30, 1998, EOP-Tabor, L.L.C. assumed a $48,108,587 loan obligation
    to Prudential Insurance Company of America in connection with the
    acquisition of One Tabor Center, Denver Colorado.

3.  On May 14, 1998, EOP-Dominion Plaza, L.L.C. issued a Promissory Note in the
    amount of $37,943,846.23 to Dom Plaza Associates, L.P., in payment of a
    portion of the purchase price in connection with the acquisition of Dominion
    Plaza, Denver, Colorado. The Promissory Note is secured by a $37,943,846,23
    Letter of Credit issued by NationsBank of Texas, N.A., for the account of,
    and reimbursement of any draws thereunder are the obligation of EOP
    Operating Limited Partnership and EOP-Dominion Plaza, L.L.C.


<PAGE>   91

                                  SCHEDULE 4.6

                          Borrower and EOPT ERISA Plans



The employees of EOPT and the Borrower (other than union employees) may
currently participate in a 401(k) Plan.

Other benefits for non-union employees include:

                                     Health care plan, dental care, vision care,
                                     life insurance and accidental death and
                                     dismemberment plan, travel/accident
                                     insurance, short-term disability, long-term
                                     disability, sick time, vacation time,
                                     personal days, holidays and direct paycheck
                                     deposit.


Union employee benefits include:

                                     Sick time, vacation time, personal days,
                                     holidays, direct paycheck deposit, monthly
                                     employer contributions into the health and
                                     welfare trust and pension fund (which
                                     health and welfare trusts and pension funds
                                     are generally Plans, Multiemployer Plans or
                                     Benefit Arrangements).


<PAGE>   92



                               SCHEDULE 5.11(c)(1)


                                  EOP-QRS Trust

                              EOP-QRS LaJolla Trust

    Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership

  Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership II

  Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership III

  Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership IV


<PAGE>   93


                               SCHEDULE 5.11(c)(2)


                                  EOP-QRS Trust

                              EOP-QRS LaJolla Trust

    Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership

  Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership II

  Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership III

  Zell/Merrill Lynch Real Estate Opportunity Partners Limited Partnership IV