And while Katie's publicist has denied any and all rumors of romance, one witness said that the Django Unchained star might have blurred some lines that night to get some:
"They danced, and after a hug he grabbed her butt and tried to seal the deal. She was flattered, but not interested."
We're just as confused about this alleged grope as one trying to figure out words that rhyme with "hug me."
Was Jamie trying to tell Katie that her ex Tom Cruise was not her maker? Was he trying to take this good girl??
Regardless, it looks like Katie was definitely up all night just for good fun you guys, even if Jamie was up all night to get lucky!
However, a friend of Katie's claims that the two "weren't flirting and have been friends a long time."
Hmm we wonder if Jamie tried to cup his star friend Katie or not? LOLz!
[Image via Dennis Van Tine/Future Image/VisualWENN.]