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                     RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                              DYNEGY HOLDINGS INC.

         The present name of the corporation is Dynegy Holdings Inc. The
corporation was incorporated under the name "Midstream Combination Corp." by the
filing of its original Certificate of Incorporation with the Secretary of State
of the State of Delaware on May 22, 1996. This Restated Certificate of
Incorporation of the corporation, which both restates and further amends the
provisions of the corporation's Certificate of Incorporation, was duly adopted
in accordance with the provisions of Sections 242 and 245 of the General
Corporation Law of the State of Delaware and by the written consent of its sole
stockholder in accordance with Section 228 of the General Corporation Law of the
State of Delaware. The Certificate of Incorporation of the corporation is hereby
amended and restated to read in its entirety as follows:

                                    Article I
         The name of the Corporation is Dynegy Holdings Inc. (the
"CORPORATION").

                                   Article II
         The address of the Corporation's registered office in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, in the City of
Wilmington, County of New Castle. The name of its registered agent at such
address is The Corporation Trust Company.

                                   Article III
         The nature of the business or purposes to be conducted or promoted is:
To engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of Delaware (the "DGCL").

                                   Article IV
         The total number of shares of common stock which the Corporation shall
have authority to issue is One Thousand (1,000) and the par value of each of the
shares is One Dollar ($1.00) amounting in the aggregate to One Thousand Dollars
($1,000).


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                                    Article V
         The Corporation is to have perpetual existence.

                                   Article VI
         In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors of the Corporation (the "Board of Directors") is
expressly authorized to make, alter or repeal the bylaws of the Corporation.

                                   Article VII
         Elections of directors need not be by written ballot unless the bylaws
of the Corporation shall so provide. Meetings of stockholders may be held within
or without the State of Delaware, as the bylaws may provide. The books of the
Corporation may be kept (subject to any provision contained in the statutes)
outside the State of Delaware at such place or places as may be designated from
time to time by the board of directors or in the bylaws of the Corporation.

                                  Article VIII
         The Corporation reserves the right to amend, alter, change or repeal
any provision contained in this Certificate of Incorporation, in the manner now
or hereafter prescribed by statute, and all rights conferred upon stockholders
herein are granted subject to this reservation.

                                   Article IX
         A director of the Corporation shall not be liable to the Corporation or
its stockholders for monetary damages for breach of fiduciary duty as a
director, except to the extent such exemption from liability or limitation
thereof is not permitted under the DGCL as the same exists or may hereafter be
amended. Any amendment, modification or repeal of the foregoing sentence shall
not adversely affect any right or protection of a director of the Corporation
hereunder in respect of any act or omission occurring prior to the time of such
amendment, modification or repeal.


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                                    Article X
         Section 10.1. RIGHT TO INDEMNIFICATION. The Corporation shall indemnify
and hold harmless, to the fullest extent permitted by applicable law as it
presently exists or may hereafter be amended, any person (a "Covered Person")
who was or is made or is threatened to be made a party or is otherwise involved
in any action, suit or proceeding, whether civil, criminal, administrative,
arbitrative or investigative (a "proceeding"), by reason of the fact that he, or
a person for whom he is the legal representative, is or was a director or
officer of the Corporation or, while a director or officer of the Corporation,
is or was serving at the request of the Corporation as a director, officer,
employee or agent of another corporation or of a partnership, joint venture,
trust, enterprise or nonprofit entity, including service with respect to
employee benefit plans, against all liability and loss suffered and expenses
(including attorneys' fees) reasonably incurred by such Covered Person.
Notwithstanding the preceding sentence, except as otherwise provided in Section
10.3 of this Article X, the Corporation shall be required to indemnify a Covered
Person in connection with a proceeding (or part thereof) commenced by such
Covered Person only if the commencement of such proceeding (or part thereof) by
the Covered Person was authorized by the Board of Directors.

         Section 10.2. PREPAYMENT OF EXPENSES. The Corporation shall pay the
expenses (including attorneys' fees) incurred by a Covered Person in defending
any proceeding in advance of its final disposition, PROVIDED, HOWEVER, that, to
the extent required by law, such payment of expenses in advance of the final
disposition of the proceeding shall be made only upon receipt of an undertaking
by the Covered Person to repay all amounts advanced if it should be ultimately
determined that the Covered Person is not entitled to be indemnified under this
Article X or otherwise.

         Section 10.3. CLAIMS. If a claim for indemnification or advancement of
expenses under this Article X is not paid in full within thirty days after a
written claim therefor by the Covered Person has been received by the
Corporation, the Covered Person may file suit to recover the unpaid amount of
such claim and, if successful in whole or in part, shall be entitled to be paid
the expense of prosecuting such claim. In any such action the Corporation shall
have the burden of


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proving that the Covered Person is not entitled to the requested indemnification
or advancement of expenses under applicable law.

         Section 10.4. NONEXCLUSIVITY OF RIGHTS. The rights conferred on any
Covered Person by this Article X shall not be exclusive of any other rights
which such Covered Person may have or hereafter acquire under any statute,
provision of this Certificate of Incorporation, bylaws, agreement, vote of
stockholders or disinterested directors or otherwise.

         Section 10.5. OTHER SOURCES. The Corporation's obligation, if any, to
indemnify or to advance expenses to any Covered Person who was or is serving at
its request as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust, enterprise or nonprofit entity shall be
reduced by any amount such Covered Person may collect as indemnification or
advancement of expenses from such other corporation, partnership, joint venture,
trust, enterprise or non-profit enterprise.

         Section 10.6. AMENDMENT OR REPEAL. Any repeal or modification of the
foregoing provisions of this Article X shall not adversely affect any right or
protection hereunder of any Covered Person in respect of any act or omission
occurring prior to the time of such repeal or modification.

         Section 10.7. OTHER INDEMNIFICATION AND PREPAYMENT OF EXPENSES. This
Article X shall not limit the right of the Corporation, to the extent and in the
manner permitted by law, to indemnify and to advance expenses to persons other
than Covered Persons when and as authorized by appropriate corporate action.


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IN WITNESS WHEREOF, the undersigned has executed this Restated Certificate of
Incorporation this 1st day of February, 2000.

                         DYNEGY Holdings INC.,

                         By:
                            --------------------------------
                            John U. Clarke
                            Executive Vice President and Chief Financial Officer