Just added to the cast - which, in addition to Stiller, already includes the criminally under appreciated Carla Gugino - are two men who know their way around a movie set: Dick Van Dyke and Mickey Rooney. Van Dyke, who hasn't appeared on the big screen since 1990's Dick Tracy (speaking of under appreciated), will play a long-time museum guard who sees a "magical pharaoh's tablet" (found by Stiller's character) as his key to perpetual youth. Along with sidekick Rooney, he sets out to steal the tablet and, presumably, crazy accidental magic things result.
Hopefully the fact that Van Dyke and Rooney (who has been away from the movies since Babe: Pig in the City) decided to appear in this film means that it's going to be really great, and not that they were both offered so much money that they don't care if the screenplay sucks. Hopefully.