This triggers when you get the "# unable to join channel (address is banned)" message. It sets a timer where it will hammer the channel every three seconds. The timer disables when you join the channel.
raw 474:*: {
if ($timer($$2)) {
haltdef
}
else {
.timer $+ $$2 0 3 .join $$2
}
}
on *:join:#: {
if ($nick == $me) && ($timer($chan)) {
.timer $+ $chan OFF
}
}