Admitted Al Qaeda member Zacarias Moussaoui is asking a federal appeals court to undo his guilty plea. He says his lawyers were prohibited from discussing with him crucial evidence in his case.

Moussaoui is serving a life sentence. He described himself as the so-called "20th hijacker" and says he was supposed to have flown a fifth airplane into the White House during the Sept. 11, 2001 attacks.

Lawyers are asking an appeals court in Virginia to toss out Moussaoui's guilty plea. They say the strict rules about what classified information could be discussed made it impossible for attorneys to properly advise him. They say that violated Moussaoui's constitutional rights.