Is this guy still around? This issue was delt with a long time ago. Please see here
http://www.newsforge.com/article.pl?sid=04/09/29/000224
If this guy put the same effort into actually building his business the way he harasses people he would be a multi-millionare by now.
Let him pursue you and anyone else he wants. If he has nothing better to do with his money, let him blow it on a legal suit he has no chance of ever winning.
Infact, I'm almost tempted to change all my mambo sites and use the code in question. Then send him an email letting him know the wonderful job that the developers have done. If he had only waited a little longer, he could have gotten what he wanted for free.