I guess I'm "old school" but I'd ask this guy "hey, you got a minute" and give him the straight poop. Look him in the eye and tell him to knock it off. If that doesn't work, your supervisor is the next step. Then when she asks if you talked to him, you can tell her exactly what was said. I would even document the conversation and his response. There's nothing better than a memo up the chain. He's an insecure little weeny and the only thing that makes him feel like a man is picking on others. Jerk!