Zynga today sued PlayerAuctions.com for enabling the sale of of their virtual items. The Facebook developer has in the past gone after other third-parties which have sold virtual currency used in their games like Mafia Wars and Farmville.

“Zynga has not authorized any third party to sell the ‘virtual currency’ or ‘virtual goods’ required to play the games,” the company wrote.

Zynga says that PlayerAuctions has interfered with the user agreement, which bars players from selling virtual items through channels outside the game. They also say that PlayerAuctions has violated Zynga’s trademarks and copyrights by using the names and images from the games.

Source: MediaPost {link no longer active}