I've heard of taking your craft seriously but this goes above and beyond. According to an "insider" close to the production of Sienna Miller's new movie Factory Girl, the sex scene between her and Hayden Christensen is real. The two actors--both 25--became very close on set while Sienna was taking a "break" from then boyfriend Jude Law. After "hanging out" for a month, Sienna left Hayden "devastated" after deciding she wasn't ready for another relationship. According to a friend of Miller:

"Sienna wanted to try to make another go of it with Jude. But again, it didn't work out. At the end of last summer, she and Hayden ended up in Toronto for more shooting. They hadn't talked in six months. But it turned out to be a great reunion."

Yeah, reunions are usually pretty fun when you come. Director George Hickenlooper was asked about the rumor by the New York Daily News

"I can't comment. You'll have to ask Sienna about it."

Which means they had sex. Anytime someone gives a coy response to what seems like a ridiculous question, the ridiculous question is usually true. Like if someone asked you if you've ever whacked off to QVC models and you didn't immediately start yelling at them, I'd have to assume that you have in fact whacked off to QVC models. Not that it's anything to be ashamed of. There was this chick on last night modeling a silk blouse. She tried to play it off, but it was pretty obvious who those seductive stares were meant for.

More pictures of Sienna and her ridiculous outfit after the jump...