help w messenger

can anyone tell me about a program that allows some d***head to kick of any one he wants inside a msn chatroom. im not real bright but im learning. i know its possibly w irc bots and yahoo to mess w people but i havent heard about on msn using messenger. can anybody tell me whats up w that and how can i block the a**hole from kicking me off whenever he feels like. also my friend was banned and she wants to know if she can unban herself. same a**hole at work. im running xp. all updates. firewall, all the good stuff. would appreciate any help. thanks