Big problem with "hackers"

So, today someone named Player came over.
The problem is, he has Owner rank and i heard that stuffing knew of it, but couldnt stop it.
Basically, i was checking over at the server to test some mcmmo commands (/party) and then he came.
I wondered who he actually is, and said "lolcanihasdiamonds" as a tiny step closer.
"The Ban Hammer has spoken!"
Well wha.
I waited a little, and i was unbanned.
Meanwhile, he caused a small restart and gave in to spamhammer and authme.
I said "lolcanihasdiamonds" again and got kicked (possibly by reddot). Then Player came back, and i said "lolcanihasdiamonds" again.
"The Ban Hammer has spoken!"
...
AAAAAAAAAAARG-
ahem.
but still, you should do something. Maybe ban the name "Player"? Make a small plugin that fucks everyone using that name over? Maybe get that shitster's IP and flip it over?

If he had Owner rank it would be impossible to do anything in game. He would have to be de-ranked and banned by console.
In regards to your ban, saying something you got kicked for purely to antagonise is going to lead to a ban. When in the heat of the moment, admin, mod, don't like to be provoked.