Digital Chocolate is suing Zynga over its use of the name "Mafia Wars," an alleged trademark infringement -- this much we know. Last night, however, Joystiq acquired the full, 157-page complaint. The crux of the suit is Digital Chocolate's common law trademark claim to the name "Mafia Wars," though the company never formally registered the name (as Zynga did last summer).

In registering the trademark last July, Zynga claims under penalty of perjury that it has "belief no other person, firm, corporation or association has the right to use the mark in commerce, either in the identical form thereof or in such near resemblance thereto as to be likely ... to cause confusion, or to cause mistake, or to deceive." It's on this stipulation which Digital Chocolate hinges its lawsuit, and the company has proof that Zynga knew about DC's version of Mafia Wars.