<PAGE>

                                 AMENDMENT TO

                     AMENDED AND RESTATED CERTIFICATE AND

                       AGREEMENT OF LIMITED PARTNERSHIP

                                      OF

                         WELLS REAL ESTATE FUND II-OW



     THIS AMENDMENT TO AMENDED AND RESTATED CERTIFICATE AND AGREEMENT OF LIMITED
PARTNERSHIP OF WELLS REAL ESTATE FUND II-OW (the "Partnership") is made and
entered into as of the 1st day of January, 2000, by and among LEO F. WELLS, III,
a Georgia resident ("Wells"), and WELLS CAPITAL, INC., a Georgia corporation
("WCI"), as the General Partners (the "General Partners"), and the Limited
Partners of the Partnership (the General Partners and the Limited Partners are
sometimes collectively referred to herein as the "Partners") for the purpose of
amending that certain Amended and Restated Certificate and Agreement of Limited
Partnership of Wells Real Estate Fund II-OW dated October 14, 1987.

                                  WITNESSETH:

     WHEREAS, the Partnership was formed pursuant to the terms and provisions of
that certain Certificate and Agreement of Limited Partnership of Wells Real
Estate Fund II-OW dated October 13, 1987, and is governed by the provisions of
that certain Amended and Restated Certificate and Agreement of Limited
Partnership of Wells Real Estate Fund II-OW dated October 14, 1987, as
previously amended to date (as so amended, the "Partnership Agreement"); and

     WHEREAS, the Partnership Agreement contemplates that the Partnership will
invest in various real properties and sets forth the agreed to allocations of
profits and losses with respect to each such investment, and certain provisions
relating to the distribution to the Partners of the net proceeds from the sale
of such properties ("Net Sale Proceeds") to the Partners; and

     WHEREAS, in connection with the original capitalization of the Partnership,
the Limited Partners were provided with a Prospectus dated November 6, 1987 (the
"Prospectus") which sets forth in summary form certain descriptions of the
allocations of profits and losses and the distribution of Net Sale Proceeds; and

     WHEREAS, Section 9.3 of the Partnership Agreement provides generally that
Net Sale Proceeds be distributed to Limited Partners in accordance with the
positive balances in their capital accounts after the allocation of Gain on Sale
provided for in Section 10.4 of the Partnership Agreement; and
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     WHEREAS, Section 10.4(c) of the Partnership Agreement provides for, among
other things, an initial allocation of Gain on Sale to Limited Partners holding
Class B Units, in proportion to and to the extent of, the amount necessary to
give each such Limited Partner holding Class B Units an amount equal to the
excess Cash Available for Distribution received by Limited Partners holding
Class A Units prior to the date of such allocation, assuming said Limited
Partners had purchased an equivalent number of Units on the same date; and

     WHEREAS, Section 10.4(c) of the Partnership Agreement further states that
it is the intent of the Partners that any disproportionate distributions of Cash
Available for Distribution made to Limited Partners holding Class A Units
pursuant to the provisions of Section 9.1(a)(i) be equalized by this provision;
and

     WHEREAS, Section 10.4(c) of the Partnership Agreement evidences the General
Partners' intent to allocate and distribute initial Net Sale Proceeds to Limited
Partners holding Class B Units in an amount necessary to equalize the
disproportionate distributions of Cash Available for Distribution previously
paid to the Limited Partners holding Class A Units on a per Unit basis; and

     WHEREAS, pursuant to Section 9.1(a)(i) of the Partnership Agreement, the
Limited Partners holding Class A Units in the Partnership have, over the life of
the Partnership, received preferential distributions of Cash Available for
Distribution from Partnership operations so that in order to effect the stated
intent of the Partners, Limited Partners holding Class B Units in the
Partnership must receive the first amount of Net Sale Proceeds distributed to
ensure that the distributions paid to Limited Partners holding Class B Units are
equalized to the distributions previously paid to Limited Partners bolding Class
A Units such that Limited Partners holding Class B Units ultimately receive the
same amount of distributions from the Partnership, on a per Unit basis, as do
the Limited Partners holding Class A Units; and

     WHEREAS, the descriptions of the distribution of Net Sale Proceeds set
forth in the section of the Prospectus entitled "Summary of the Offering" and
the section of the Prospectus entitled "Distribution Policies - Residual
Proceeds" state a general intention of the General Partners to make
distributions of Net Sale Proceeds first to the Limited Partners in the amount
necessary to return their capital contributions plus a 12% per annum cumulative
return thereon, less all prior distributions of Cash Available for Distribution,
then 85% to the Limited Partners and 15% to the General Partners; and

     WHEREAS, the Partnership Agreement provisions setting forth the allocation
and distribution of Net Sale Proceeds set forth in Section 9.3, when read in
conjunction with the provisions regarding the allocation of Gain on Sale set
forth in Section 10.4(c) described above, along with the various provisions of
the Prospectus describing the distribution of Net Sale Proceeds described above,
are inconsistent and ambiguous; and

     WHEREAS, Section 11.2(b) of the Partnership Agreement grants the General
Partners the authority to amend the Partnership Agreement without the consent or
vote of the Limited Partners to cure any ambiguity or to correct or supplement
any provision in the Partnership Agreement which may be inconsistent with any of
the other provision of the Partnership Agreement; and
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     WHEREAS, in view of the foregoing inconsistent and ambiguous sections of
the Partnership Agreement relating to the distribution of Net Sale Proceeds
referred to above, the General Partners are now desirous of correcting and
clarifying such provisions and curing the currently existing ambiguities with
respect to distributions of Net Sale Proceeds; and

     WHEREAS, the General Partners have deemed it to be fair and in the best
interest of the Partners that the distribution of Net Sale Proceeds be made in
accordance with the General Partners' original intention, as evidenced by
Section 10.4(c) of the Partnership Agreement, to allocate and distribute Net
Sale Proceeds as follows: (a) first, to Limited Partners holding Class B Units
in an amount necessary to provide them with cash distributions equal to the Cash
Available for Distribution previously paid to the Limited Partners holding Class
A Units on a per Unit basis; (b) then, to Limited Partners on a per Unit basis
until each Limited Partner has received distributions equal to the sum of his
Capital Contribution, plus an amount equal to his Cumulative Distribution, less
the sum of all prior distributions to such Limited Partner; and (c) finally, 85%
thereof to the Limited Partners and 15% thereof to the General Partners.

     NOW, THEREFORE, in consideration of the foregoing premises and the mutual
benefits, covenants and conditions herein contained, the parties hereto do
hereby amend the Partnership Agreement as follows:

                            AMENDMENT TO ARTICLE IX

     Section 9.3 of Article IX of the Partnership Agreement is hereby deleted in
its entirety and the following provision is inserted in lieu thereof:

     "9.3 Net Sale Proceeds. Except as otherwise provided for in Section 9.4
          -----------------
hereof in connection with a dissolution and liquidation of the Partnership, and
except for the potential reinvestment of Net Sale Proceeds as provided in
Section 11.3(g) hereof, Net Sale Proceeds shall be distributed as follows: (a)
first, to each Limited Partner holding Class B Units, in proportion to and to
the extent of, the amount, if any, necessary to give each Limited Partner
holding Class B Units an amount of Net Sale Proceeds equal to the excess Cash
Available for Distribution received prior to the Allocation Date by each Limited
Partner holding Class A Units under Section 9.1(a)(i) hereof, assuming said
Limited Partners had purchased an equivalent number of Units on the same date;
(b) then, to the Limited Partners until each Limited Partner has received
Partnership distributions in an amount equal to the sum of his Capital
Contribution, plus an amount equal to his Cumulative Distribution, less the sum
of all prior distributions made to such Limited Partner; and (c) finally,
eighty-five percent (85%) thereof to the Limited Partners and fifteen percent
(15%) thereof to the General Partners."

                                RECERTIFICATION

     Except as set forth above, the Partnership Agreement, as specifically
amended hereby, shall continue and remain in full force and effect.
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     IN WITNESS WHEREOF, the undersigned have executed this Amendment to Amended
and Restated Certificate and Agreement of Limited Partnership of Wells Real
Estate Fund II-OW as of the day and year first above written both as parties
hereto and on behalf of the Limited Partners pursuant to that certain power of
attorney granted to the General Partners pursuant to the provisions of Section
19.1(a)(iv) of the Partnership Agreement.


                              GENERAL PARTNERS:
                              ----------------


                              /s/ Leo F. Wells, III      (SEAL)
                              ---------------------------
                              LEO F. WELLS, III


                              WELLS CAPITAL, INC.
                              A Georgia corporation


                              By:  /s/ Leo F. Wells, III
                                 ------------------------------------
                                 Leo F. Wells, III, President