This plugin provides channel ops with an automated repeat-flood kicker. It will NOT kick on a general flood from a user, only on a flood of repeated lines. It counts the number of repeats within a 30-second period. If someone is repeating at a slower rate than that, it's not really a flood, and you can deal with it manually.
When someone has reached the limit set with the command, they are kicked (but not banned) from the channel. If they exceed the limit, they are banned. In practice, this usually means if they're flooding fast they get banned pretty much right away. If they're flooding slowly or just being annoying they get kicked as a warning, then if they come back and continue to do it they get kickbanned.
For what it's worth, only the first 64 characters of each line are checked; if they're identical it's a repeat.
/repeatlimit count kickmsg
This sets the number of repeated lines that count as a flood, and sets the message used to kick the flooders. Note that the count is the number of *repeats* of the same line. If someone says 'foo' 3 times, that's 2 repeats.