What is the test for evidence of prior act or subsequent act in the context of Section 404(b) of the Criminal Code?

By its very terms, 404(b) does not distinguish between "prior" and "subsequent" acts. We have specifically allowed prior act evidence to prove knowledge. United States v. Marsh, 894 F.2d 1035, 1038 (9th Cir.1989), cert. denied, --- U.S. ----, 110 S.Ct. 1143, 107 L.Ed.2d 1048 (1990). Moreover, in United States v. Mehrmanesh, 689 F.2d 822, 832-33 (9th Cir.1982), we allowed subsequent act evidence to prove intent. In Mehrmanesh, a witness testified that Mehrmanesh possessed and sold large quantities of drugs after his arrest for attempting to possess with intent to distribute heroin. The government sought to use the testimony concerning Mehrmanesh's subsequent activities to prove that he previously "intended something more than the mere personal use of the heroin at issue in [the] case." Id. at 832. We concluded that the jury properly could draw such an inference regarding intent.