Bump.
I'm glad this worked for you, but this solution didn't do anything for me, as the network I'm trying to connect to doesn't broadcast its SSID and I have connected to it under iOS5 countless time using the same method, but it fails every time now.
I've tried every solution suggested by this thread short of resetting my device (Reset network setting, reset device, turn wifi on/off, etc... Since I can't connect, renewing lease or changing DNS setting isn't even an option), but seeing as how I've visited a local apple dealer and confirmed that their brand new iPad Mini (Less than a week old) had the same exact problem, I'm almost certain it will not fix my problem.
The most annoying this about this is that for me, it was having problems switching between networks after iOS 6 update, but I was always able to get a connection eventually. But as of two weeks ago, it broke completely and 6.0.1 did nothing to solve this issue. I can only connect to open networks now.
Anyone with a different solution - please help me out.
I'm using the "abandoned-by-Apple" iPad 3 running iOS 6.0.1