A Virginia software developer has pleaded guilty in a Detroit federal courtroom in a scam involving bulk commercial e-mails called spam.

Forty-nine-year-old David Patton of Centreville, Virginia pleaded guilty Tuesday to aiding and abetting violations of the CAN-SPAM Act of 2003.

Patton is the ninth defendant to enter a guilty plea in the case in which millions of unsolicited e-mails were sent out to inflate the price of Chinese stocks.

He faces up to six years in prison, a $3,000 fine and the forfeiture of $50,100 in proceeds from the sales of his software.

In his plea deal, Patton acknowledges that he knew other defendants used at least two of his programs to send large volumes of spam while disguising their true origins to evade spam-blocking filters.