During a 'lull' in her career, Jess did a workout tape for fitness video company Speedfit.

Unfortch, we prob aren't gonna get to see that any time soon. Simpson and Poppa Joe are now trying to prevent the release of the tape

The owner of Speedfit, Alex Astilean, is totally pissed because Jess signed a multimillion-dollar contract with them. He sued Jugs last year for $10 mill and since she didn't want to settle, well, now he's a comin' after Jess' daddy/manager, Joe, too.

In regards to this ongoing battle, Astilean said, "They are hurting millions of fat people in America."

Those are fighting words!

A Simpson rep said, "It's a legal matter that's in the hands of attorneys."