Mel Gibson Confirmed for 'Hangover 2'; Zach Galifianakis Frustrated?

MTV News has confirmed that Mel Gibson will in fact make an appearance in The Hangover 2. While this may be good news to Hangover fans, Hangover star Zach Galifianakis is reportedly feeling "frustrated" on set. But hey, maybe Mel coming to set is just the kind of guy that can cheer him up!

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According to two MTV News sources close with The Hangover 2 production, Mel "is confirmed."

As the film gets underway you'd think the stars are excited to be reunited, but New York Magazine's Vulture section reports that Zach may not be that thrilled.

The comedian chatted with Scott Aukerman on a Comedy Death-Ray podcast this month and said he's had to turn some projects down due on moral grounds.

"But a movie you're acting in, you don't have a lot of control — you just show up and vomit your lines out. I'm not the boss," Zach said on the show. "I'm in a deep protest right now with a movie I'm working on, up in arms about something. But I can't get the guys to listen ... I'm not making any leeway."

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When the host started to say the title of the film, Zach gave a warning sound and cut him off. But, Aukerman persisted and said, "I know you're filming The Hhhhhhhh ... "

"It has something to do with a movie I'm working on, yeah," Zach admitted. "I'll tell you about it later. It's very frustrating."

Hopefully Zach's frustrations are now fixed or didn't have to do with The Hangover 2. It just wouldn't be the same without Alan!