You can definitely do it and it's not much different to doint it with Aruba.
I've got a customer running WLC's for ClearPass Guest and general 802.1x.
You still define CPPM as the radius server in the WLAN profiles like you would with Aruba. The real changes are in how the guest stuff works. Cisco publishes an application note on the web redirect procedure. you need to push 2 Cisco VSAs out to trigger a captive portal redirect. You can also specifiy the web login page in the WLC WLAN profile.
see here for more info.
http://www.cisco.com/c/en/us/support/docs/wireless-mobility/wlan-security/115951-web-auth-wlc-guide-00.html