United States v. Padilla, __ F.3d __ (9th Cir. Nov. 12, 2004) (conviction for felon in possession of firearm, under 18 U.S.C. 922(g)(1) was not invalidated by post-conviction nunc pro tunc state court invalidation of underlying felony conviction; conviction remains valid since defendant was a felon at the time of the federal conviction).