This is my situation exactly. Websense blocks all apple.com connections. Since the stupid check fails, my legitimate and successfull connection is disconnected by a braindead "improvement" in ios6.
This is so frustrating that I may just "downgrade to a more familiar experience" being 5.1.1. Apple is sure learning a few things from M$..
Oh, and just in case anyone was wondering 6.0.1 did nothing to resolve this. Give us the option to have it check the connection or not. Some networks do not connect to the internet, we have several at work that are that way.
While your at it Apple, give me the option to leave the wifi on and consume some battery. It disconnecting every time it goes to sleep is very annoying. I think I know how best ot manage my own battery. A fully charged battery on a phone that does not do what you want it to is absolutely useless in my opinion...