Kristen Stewart's 'New Moon' Potty Mouth

Kristen Stewart may play iconic, bad ass rocker Joan Jett and partake in some girl-on-girl action on screen with Dakota Fanning in The Runaways, but while filming New Moon the beloved actress had a potty mouth off camera!

New Moon director Chris Weitz told PopEater that Kristen took the cake for the number of curse words on set.

"It's Kristen by several lengths actually," Chris said.

What cuss words gave Kristen the title of champion swearer?

"I couldn't say over a domestic phone line," the director quipped.

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Unfortunately, there is not a blooper real of Kristen's potty mouth on the New Moon DVD, which to the delight of Twi-hards was released everywhere this weekend!

"I think that blooper reel would take us into NC-17 territory," the director told PopEater. "I don't think that's what Summit Entertainment has in mind in terms of extras."

What additional features will fans enjoy on the DVD? A wholesome documentary on the making of the movie and commentary from Chris and editor Peter Lambert.

There are no deleted scenes and no bloopers (sigh); however, deleted scenes will be included on future DVD releases.

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"Everyone likes to say that things were hilarious on the set, but we were working so hard that we couldn't afford to have bloopers," Chris said. "Every take counted."

The clean takes that is.

"Those kids have some mouths," he said. "Except for Taylor (Lautner). He was always very well-spoken."