Why can't you talk to him man to man? I had a co worker who had the same problem. Everyone made fun of him behind is back, but no one said anything to him to his face. It pissed me off because he was one of the nicest people I ever met, to this day. One day I took him aside and asked him if he knew people made fun of him because he stank. I told him I wasn't trying to be funny, but that I thought he should know. He was hurt, but he understood. He thanked me, and went to his doctor, who changed his medication. Give it a shot.