The fraud involved financial cooking of books but was characterized by prosecutors as an elaborate Ponzi scheme, in which the company would use newly invested money to pay off its earlier debt.

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Earlier this month, Bush proposed doubling the maximum prison term for corporate fraud and vowed to "end the days of cooking the books" after revelations of misdeeds by Enron, WorldCom and other major companies.

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It was due to deceitful, and perhaps illegal, games played by corporate executives: diverting funds into secret partnerships, cooking the books to keep those deals secret, lying to investors and employees about the financial health of the company, while selling their own stock to make sure they wouldn't be hurt when the whole house of cards collapsed.

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