It's an Iron Man sequel rumor no more:

Sam Rockwell will, indeed, portray Justin Hammer in the 2010 follow-up film.

“We had a phone conversation about it... They were like, we don’t have a script but this is the deal and this is the character," Rockwell told MTV.

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Rockwell said he signed on, though, because he was a fan of the original Iron Man, which his girlfriend - the gorgeous Leslie Bibb - played a role in.

As for this Justin Hammer fellow?

“He’s a rival [of Tony Stark],” Rockwell said. “He takes over all the weapons stuff after Tony’s left.... I don’t know if he takes over Stark Industries... He’s a money dude. That’s about all I can say.”