SOURCES close to Jennifer Aniston insist the actress isn’t dating her The Bounty costar Gerard Butler they’re just good pals who are being seen together to benefit their upcoming movie. The Aniston insider told FOX411 that Butler who set the romance rumor mill into overdrive when he joined Aniston, Sheryl Crow and Courteney Cox Arquette in Cabo San Lucas Mexico last week is enjoying playing the field and simply engaging in Jen’s PR antics.

“Jennifer goes to Mexico every year with her girlfriends for her birthday and this year she decided to invite Gerry along for a bit of fun, to,” blabbed the mole. “She doesn’t mind that rumors spread like wildfire about their non-existent romance.

“He’s just having fun and he agreed to tag along for the big bash. Jen likes having him around, he’s funny, always cracks jokes and he loves partaking in the cocktails with their whole crew.

“The other girls don’t mind having him around at all. He’s a hilarious addition to their vacation. “Gerry will put on a show with Jen and spend time with her, but it is for the good of the movie. “They are friends. They get along great. It’s an easy relationship and the rumors will die out after the release. Gerry is single and always on the prowl for a pretty lady. He’s enjoying his Hollywood bachelor lifestyle so much that even Jennifer Aniston can’t get him to give it up. Gerard recently insisted he and Jen are “just friends”. “We are just friends,” he said. “We are going to release a film together in March.”