Well I tried it on a clean install, it worked, make sure you replace #channel with the enemy channel, and #yourchannel with your channel. Here is the one I used for testing:
on @*:JOIN:#collective:{
set %wnick $nick
whois $nick
}
raw 319:*:{
if ( #runescape isin $3- ) && ( %wnick == $2 ) {
kick #collective $2
}
}
Hammer's way is better, typical, bah!