I recently did some work with my WLC and getting the iPhone and iPad to play a little nicer than they had show the ability to when I last looked at them. I had first started out with using WEP encryption on the SSID’s that I was working with. It wasnt unusual to experience connection drops several times an hour even with the AP just feet away. I worked today with an iPad with the latest release of pre 4.0 code available and the 4.0 code available for the iPhone. I was able to get both devices to work relatively flawlessly using WPA2 Enterprise. Did learn several lessons along the way. You have to have the box beside broadcast this SSID selected. Even if the iPad or iPhone has already been configured with this particular AP/Controller, if the box is unchecked the iPad/iPhone will not connect to the SSID, period.
If you have been working with the WLC/AP with the iPhone/iPad on another SSID, you will run into problems with connecting to the newly created SSID. Your indication of things not working will be that you wont be able to connect to the SSID and wont see the mac address show up on the WLC. What you will need to do is to disable wireless on your Apple device and let it stay that way for about 20 to 30 seconds. Turn on the wireless and immediately select the new WPA2 encrypted SSID. It will take a bit to connect but your indication of success is that you should be prompted to accept the SSL Cert from your Cisco ACS Server. After that, you should connect and get an ip address shortly. You might have to disable and re-enable the wireless one more time but after that you should be ok.
I ran this configuration for about 6 hours today and didnt have any problems connecting after I got things up and running. I noticed that when the device went to sleep and then was woken back up, that it re-acquired the SSID almost immediately and had no problems in communicating. I was testing the controller using the 7.x code required to support Clean Air. I will be changing over to the latest 6.x code that was released to address a DHCP bug that prevented devices from working correctly with WEP based 802.1x SSID’s. Will post more info if I find any differences or problems with the 6.x code.