you dont, proof is you are here talking about it.
but as i am a forum moderator as well on another web site, i can tell you that many times you are not perma banned, its just that the administrators have forgotten about you and at one point they will just look at the list and unban a lot of people just because they dont even remember why you were banned.
though this is blizzard, a big company i suspect they keep a log of what hapenned with each persons.
you could still send them an email asking to be unbanned and that you learned your lessons and all, that it wont happen again... all the bullshit they wanna hear about. it might unban you !
