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                                                                    EXHIBIT 4.29

             ACKNOWLEDGMENT AND AMENDMENT TO STOCK TRADING AGREEMENT

     This Acknowledgment and Amendment to Stock Trading Agreement (this
"AGREEMENT") is dated as of April 17, 2003 and is made by Electric City Corp., a
Delaware corporation (the "COMPANY"), and Munder Power Plus Fund ("MUNDER").

                              W I T N E S S E T H:

     WHEREAS, MUNDER and the Company are parties to that certain Securities
Purchase Agreement, dated as of April 17, 2003 (the "SECURITIES PURCHASE
AGREEMENT") whereby the Company has agreed to sell and MUNDER has agreed to
purchase shares of the Company's Common Stock (as therein defined) together with
warrants to purchase additional shares of Common Stock (the "WARRANTS"); and

     WHEREAS, it is a condition precedent to the obligation of the Company to
issue and sell, and the obligation of MUNDER to purchase, such shares of Common
Stock and such Warrants that the Parties hereto enter into this Agreement;

     NOW, THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the Parties agree as follows:

     1.   DEFINED TERMS. Capitalized terms used in this Agreement which are not
otherwise defined herein are used with the meanings given such terms in the
Securities Purchase Agreement. In addition, the following additional term when
used in this Agreement has the meaning indicated:

          "WARRANT SHARES" means any shares of Common Stock issued pursuant to
     exercise of the Warrants.

     2.   AMENDMENT OF STOCK TRADING AGREEMENT. That certain Stock Trading
Agreement dated as of December 16, 2002 between MUNDER and the Company (as
amended hereby and as it may be further amended, restated, modified or
supplemented and in effect from time to time, the "STOCK TRADING AGREEMENT"), is
hereby amended by amending and restating the definition of Common Stock therein
as follows:

          "COMMON STOCK" means and includes all shares of the Company's common
     stock, par value $0.0001 per share, which have been or hereafter are
     acquired by Munder pursuant to (i) the Munder Securities Purchase Agreement
     or the Common Stock Warrants issued to Munder pursuant to the Munder
     Securities Purchase Agreement, (ii) the Securities Purchase Agreement dated
     as of April 17, 2003 between Munder and the Company or the Common Stock
     Warrants issued to Munder pursuant to such Securities Purchase Agreement,
     or (iii) with respect to shares of the Company common stock described in
     clauses (i) and (ii) immediately preceding pursuant to any stock split,
     reverse stock split, stock dividend or other similar event, affecting the
     Company's common stock generally.

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     3.   TRADING RESTRICTIONS. MUNDER hereby agrees that the shares of Common
Stock and any Warrant Shares shall be subject to the provisions, terms,
conditions and trading restrictions applicable to MUNDER under the Stock Trading
Agreement, and further agrees that the Company shall be entitled to enforce
MUNDER's obligations under this Agreement and the Stock Trading Agreement with
respect to all such shares of Common Stock and all such Warrant Shares.

     4.   LEGEND ON SHARE CERTIFICATES. MUNDER further agrees that all shares of
Common Stock and all Warrant Shares that are subject to the terms and provisions
of this Agreement and the Stock Trading Agreement shall, in addition to such
legends as may be required by law and any other legend required by any agreement
or document executed in connection with the Securities Purchase Agreement shall
bear the following legend:

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          THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
          REQUIREMENTS AS TO TRADING CONTAINED IN THE STOCK TRADING AGREEMENT,
          DATED AS OF DECEMBER 16, 2002, BETWEEN THE COMPANY AND THE HOLDER, A
          COPY OF WHICH IS ON FILE WITH THE SECRETARY OF THE COMPANY.

     Upon the termination of the Stock Trading Agreement or for sales in
conformance with the provisions of the Stock Trading Agreement, MUNDER (or the
applicable purchaser) shall be entitled to receive, in exchange for any security
bearing the legend regarding the Stock Trading Agreement, a security without
such legend.

     5.   INJUNCTIVE RELIEF. It is acknowledged that it is impossible to measure
in money the damages that would be suffered if MUNDER fails to comply with the
obligations imposed on it by this Agreement and that, in the event of any such
failure, the Company would be irreparably damaged and would not have an adequate
remedy at law. The Company shall, therefore, be entitled to injunctive relief
and/or specific performance to enforce such obligations of MUNDER, and if any
action should be brought in equity to enforce any of such provisions of this
Agreement, MUNDER shall not raise the defense that there is an adequate remedy
at law.

     6.   GOVERNING LAW. Except as to matters governed by the General
Corporation Law of the State of Delaware and decisions thereunder of the
Delaware courts applicable to Delaware corporations, which shall be governed by
such laws and decisions, this Agreement shall be construed and enforced in
accordance with, and the rights of the Parties shall be governed by, the laws of
the State of Illinois.

     7.   ENTIRE AGREEMENT; WAIVER. This Agreement together with the Stock
Trading Agreement contain the entire agreement among the parties hereto with
respect to the subject matter hereof. No waiver of any term or provision shall
be effective unless in writing signed by the party to be charged in accordance
herewith.

     8.   BINDING EFFECT. This Agreement shall be binding on and inure to the
benefit of the parties and, subject to the terms and provisions hereof, their
respective legal representatives, successors and assigns.

     9.   INVALIDITY OF PROVISION. The invalidity or unenforceability of any
provision of this Agreement in any jurisdiction shall not affect the validity or
enforceability of the remainder of this Agreement in that jurisdiction or the
validity or enforceability of this Agreement, including that provision, in any
other jurisdiction.

     10.  COUNTERPARTS. This Agreement may be executed in two or more
counterparts, all of which shall be deemed but one and the same instrument and
each of which shall be deemed an original, and it shall not be necessary in
making proof of this Agreement to produce or account for more than one such
counterpart for each of the parties hereto. Delivery by facsimile by any of the
parties hereto of an executed counterpart of this Agreement shall be effective
as an original executed counterpart hereof and shall be deemed a representation
that an original

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executed counterpart hereof will be delivered.

     11.  NOTICES. All notices, consents and other communications under this
Agreement shall be in writing and shall be deemed to have been duly given when
given in accordance with the provisions of the Stock Trading Agreement.

       [Balance of page intentionally left blank; signature page follows.]

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     IN WITNESS WHEREOF, the parties hereto have executed this Acknowledgment
and And Amendment To Stock Trading Agreement as of the day and year first above
written.


ELECTRIC CITY CORP.                     MUNDER POWER PLUS FUND, A
                                        SERIES OF THE MUNDER FUNDS, INC.


By:   /s/ John Mitola                   By:  /s/ Stephen Shenkenberg
    -----------------------------           --------------------------------
Name:  John Mitola                      Name:    Stephen Shenkenberg
                                               -------------------------------
Title: Chief Executive Officer          Title:   Vice President & Secretary
                                               -------------------------------

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