Brad Pitt Attacker -- Gettin' Dirty with Brad On His Mind

The guy who bum rushed Brad Pitt at a Hollywood premiere is still hung up on Pitt -- even as he begins serving his sentence for the attack.

Vitalii Sediuk was wearing a tank top emblazoned with Brad's pic while he picked up garbage as part of his court-ordered community service.

Sediuk pled no contest to the attack -- he was ordered to stay away from Pitt and Angelina Jolie and has to do 20 days labor -- mostly clean-up duty.