[pendy]

Very difficult. I had this at one company, and it took straight talking to deal with the problem. Look at it this way - he may claim low self-esteem (which seems to be a useful excuse for everything from niffing to beating up old ladies), but he obviously doesn't care that he is making other people's working environment unpleasant. He has been told once, and did something about it, albeit for a short time. You may well have to bite the bullet and say "Look mate, you niff, and it is unpleasant for all of us. You must do something about it, or you may well lose your job". If he doesn't heed the warning, there's nothing more you can do except fire him.