Is John Mayer Kissing Up to Another Woman?

Jennifer Aniston is currently starring opposite a loveable pooch in the box office smash Marley & Me, but it’s her real-life boyfriend who just might wind up the doghouse.

Aniston, 39, reunited with John Mayer in October after the pair intially broke things off last August. They’d been dating for throughout the summer.

But now In Touch reports that 31-year-old rocker Mayer  was seen smooching a knockout blonde at Santa Monica, California’s Marix Tex Mex Restaurant on Wednesday.

“They were obviously on a date,” an insider tells the publication. “He came in with her another time, too, and I’ve seen them out together.”

But while it’s expected that Mayer would likely have female friends in his inner circle, the source tells the mag that things were getting a bit heated with the two during their heated oceanside redezvous.

“He gave her a long kiss before they left,” the snitch adds. “John has been here six times in the last two weeks but never with Jen.”

Of course, the timing couldn’t be worse. Aniston’s 40th birthday is on February 11, and rumors had Mayer looking to surprise her with an engagment ring.

Jennifer Aniston might want not want to dig out the his ‘n’ hers matching cargo pants again just yet.