Since the JB OTA update, I have been unable to connect to the corporate wifi at work. It worked fine on ICS, using 802.1x EAP (PEAP). Apparently there is a bug in 4.1.1 that prevents connecting to that type of wifi network. Good news is there is a fix in 4.1.2, although when we get that update is anyone's guess. There is a patch you can apply if you need to. This also affects Nexus 7 tablets and other JB devices. Here is a reference and the patch:

Issue 34212 - android - On Jelly Bean, failed to connect to WPA enterprise wireless - Android - An Open Handset Alliance Project - Google Project Hosting