llohancourtroom_dotsX17.jpgLindsay Lohan may be headed to jail next week, but based on what we're hearing, she's definitely NOT on her best behavior!

The other night Lilo reportedly crashed the party for Leonardo DiCaprio’s new movie J. Edgar at the Roosevelt in Hollywood, and spies at the bash tell the NY Post that she caused such a scene, she made A-list attendees “uncomfortable.” Yikes!

Lindsay apparently insisted she was an invited guest to the party, and she even talked her way past hotel security! A source at the bash told the NY Post, “Lindsay was arguing with the security to let her in, dropping every celebrity’s name to get in. She could be heard saying, ‘I have to go and see Leo.’"

“Eventually they let her in, but she made everybody uncomfortable," the source continued. "She was aggressive and random, storming around. She tried to get to Leo, but he was surrounded by his security and a posse of his friends. Clint and Leo and Dustin Lance Black were talking, and Lindsay sent one of her aides over, demanding to get a photo with them, but security shooed them away.”

However, Lindsay's rep has a different story, telling the Post, “She did not crash, she was invited by a guest who attended the event. I am not aware of her asking for photos with Leo or Clint. She was never asked to leave."