Commercial Metals (CMC) 10-Q 2008 Q3 Quarterly report

EXHIBIT 32.2

CERTIFICATION 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 of Commercial Metals Company (the “Company”) on Form 10-Q for the period ended May 31, 2008 (the “Report”), I, William B. Larson, Senior Vice President and Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

     (1) the Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

     (2) the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ William B. Larson  

William B. Larson 

Senior Vice President and Chief Financial Officer 

Date: July 10, 2008

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