I've tried the following:
* Settings | General | Reset | Reset Network Settings (Twice)
* Settings | General | Reset | Reset All Settings (Once)
* Plugging it in and doing a "Restore" through iTunes (that's how I downloaded iOS 5.1.1 in the first place)
All the passcodes and restrictions are are turned off.
When I first try to connect to the network, I'm prompted to enter my username and password (I've elected to "forget" the network a few times so I can get this screen again). If I enter it wrong, then I just get an error that I'm not connected. When I enter it right, I get a warning that the certificate is "not verified". When I click on "More Details", I can see all the information that got pulled from the network (Issuer Name, Signature Algorithm, Public Key Algorithm, Key Usage, etc.). When I choose to "Accept", I get the little icon indicating that it's trying to connect...this never goes away (I let it run for an hour).
The encryption type on the main Wifi I'm trying to connect to says it's RSA (I'm guessing it's WEP though...I didn't set it up, our IT group did that).
I just got it working, and you'll never believe how I did it...
After watching some YouTube clips, I decided to try something way-off in left-field. I put the iPod Touch on ice for about 10 min. (This was easy to do because I bring a cooler with me to keep some things cool at work. I just put it in with my lunch.) When I turned it on and went to the network settings (like I'd been doing all morning); cha-ching, it worked great! I wouldn't have believed it myself if I hadn't have seen it.