add them with /guser -a blacklist $1 3 <reason>
your on join could look like this:
Code:
on @blacklist:join:#: {
  ban -u30 $chan $nick 3
  kick $chan $nick BLACKLISTED!
}

but then again, what do I know .. I'm NoScRiPtR wink

But then again, what do I know ... I'm NoScRiPtR wink