Exhibit (32)(a)
Certification of CEO and CFO Pursuant to
18 U.S.C. Section 1350,
as Adopted Pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002
In connection with the Quarterly Report on Form 10-Q of CMS Energy Corporation (the
“Company”) for
the quarterly period ended
September 30, 2007 as filed with the Securities and Exchange Commission
on the date hereof (the
“Report”),
David W. Joos, as President and Chief Executive Officer of the
Company, and
Thomas J. Webb, as Executive Vice President and Chief Financial Officer of the
Company, each hereby certifies, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section
906 of the Sarbanes-Oxley Act of 2002, that, to the best of his knowledge:
(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the
Securities Exchange Act of 1934; and
(2) The information contained in the Report fairly presents, in all material respects, the
financial condition and results of operations of the Company.