Uh did you even check if your IP was the same as before after you did it or not? If yuo don't know how 2 check your IP go 2 www.ipchicken.com, release/renew then go back 2 ipchicken.com and see if it's the same like I said, your host my hold your Mac assigned to a IP for like 10 mins when you're not connected. So maybe staying offline for that period of time then reconnecting your modem you might have it changed... Also it might not even be a "ip ban" it could be a "temperary restriction" as bnet calls it which restricts your Cd-key from that server. So you might wanan change your key if changing your IP doesn't fix the issue.