EXHIBIT 3.4(a)

                            CERTIFICATE OF FORMATION

                                       OF

                         ENCORE OPERATING LOUISIANA, LLC

            This Certificate of Formation of ENCORE OPERATING LOUISIANA, LLC
(the "Company") is being executed and filed by the undersigned authorized person
for the purpose of forming a limited liability company under the Delaware
Limited Liability Company Act.

                                   Article One

            The name of the Delaware limited liability company formed hereby is
ENCORE OPERATING LOUISIANA, LLC.

                                   Article Two

            The address of the registered office of the Company in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, Wilmington, New Castle
County, Delaware 19801, and the name and address of the Company's registered
agent for service of process at that address is The Corporation Trust Company.

            IN WITNESS WHEREOF, the undersigned has executed this Certificate of
Formation on July 17, 2003.

                                                 AUTHORIZED PERSON

                                                 /s/ SEAN T. WHEELER
                                                 -------------------------------
                                                 Sean T. Wheeler
                                                 Authorized Person