Something

ON *:INVITE:#:{
set %invite.nick. $+ $chan $nick
set %invite.chan. $+ $chan $chan
join $chan
}
ON *:JOIN:#:{
if ($($+(%,invite.chan.,$chan),2)) {
.timer 1 1 chancheck $1
}
}
Alais chancheck {
if ($($+(%,invite.nick.,$1),2) !isop $1 && $($+(%,invite.nick.,$1),2) !Ishop $1) {
part $1 I must be invited by a channel op
unset %Invite.*. [ $+ [ $1 ] ]
}
}