ObjIRC  Diff

		user = [IRCUser IRCUserWithString: who];

		if ([[user nickname] isEqual: _nickname]) {
			[_nickname release];
			_nickname = [nickname copy];
		}

		enumerator = [_channels keyEnumerator];
		enumerator = [_channels objectEnumerator];
		while ((channel = [enumerator nextObject]) != nil) {
			if ([channel containsObject: [user nickname]]) {
				[channel removeObject: [user nickname]];
				[channel addObject: nickname];
			}
		}