Adam Lambert made quite the impression at Lady Gaga’s surprise twenty-fifth birthday party Sunday night, and not in a good way.

The American Idol alum, 29, wasn’t even invited to the bash at L.A.’s La Cita Mexican restaurant, but attended as a guest of the Scissor Sisters, who have been opening for the “Born this Way” singer on tour, Perez Hilton told the Morning Dish radio program Thursday.

“Adam showed up beyond drunk,” said the gossip blogger. “Super sloppy embarrassingly drunk!”

Lambert began some intense fist-pumping and kept beating on the walls until he’d actually punched a hole in the building’s low ceiling, Hilton said.

And another eyewitness tells UsMagazine.com, “Adam acted like an animal. He kept jumping up on the tables and chairs and screaming. When they brought the cake out he tried to smear it in Gaga’s face and put a doll from the cake in her mouth!”

Then the “Whataya Want from Me” singer tried to serenade the birthday girl, “like he was auditioning for Idol again!” Hilton said.

Eventually Gaga asked her security to kick him out, added the witness.

A rep for Lambert had no comment on the incident, but a few days later, Lambert acknowledged his bad behavior on his Twitter page.

Music Video