John Mayer was looking typically annoyed at the Costume Institute Gala, the last time he was seen out with Jessica Simpson. Now Perez Hilton is reporting that Mayer and Simpson are done. Someone should tell her dad.

The split happened very recently. “They officially called it quits this past weekend,” a well placed source tells us. “They’d been having problems for a while now and just decided it’d be better to end things.”

This news will come as a surprise to many, especially Jessica’s dad – who just a few days ago was publicly praising Mayer in the press.

While Jessica is currently in Cannes – seemingly having a great time – John is wasting no time enjoying the single life either.

Mayer and his entourage hit up New York City club Stereo on Thursday night, and the rocker was having a really good time.

“He was f***ing drunk off his ass and was spending a lot of time with an ugly brunette that was not Jessica Simpson,” a spywitness tells us.

[From PerezHilton via Best Week Ever]

I’ve been burned reporting Perez’s “exclusives” before so I would venture to guess someone told him that John Mayer was hanging out with a brunette that was not Simpson and he turned it into “multiple sources confirm” that they’re done.

Still, it’s not like anyone expected these two to last. TMZ is now carrying the story, but there’s no confirmation from either of their publicists.

Meanwhile there’s a story today that Jessica is no longer representing charity “Operation Smile,” on whose behalf she spent just 2 out of 10 days visiting children in October of 2005 during a trip to Africa she credits with helping her decide to break up with her ex husband, Nick Lachey.