ISE, WLC: web auth, blocking user account

Question

Hello!
We are implementing BYOD concept with ISE (1.1.4) and WLC 5508 (7.4.100).
On WLC there is SSID(WLAN) with MAC filtering without L2 security. For authentication user is redirected to the ISE Guest Portal.
Credentials are created at the ISE sponsor portal.
We create user account in ISE sponsor portal with one hour lease.
In 10 minutes we delete (or block)  user credentials.
In spite of it the user is still able to work. Even if we manually disconnect client and reconnect it again, client opens the browser and there is no redirection to the ISE web auth page.
This happens because WLC thinks, that client is still associated.
There are session and idle timeout timers in WLC WLAN, but they can't solve the problem of automatic client session removing.
From my point of you, ISE must send some kind of reauth request to the user after account deletion, to make user authentication impossible .
In practice, ISE doesn't tell wlc or user, that client sesssion is blocked.
How the user account blocking process can be automated without manually deleting the client session from WLC client database?

Answer 1

It seems that there is some bug about CoA when deleting Guest accounts
CSCuc82135
Guests need to be removed from the network on Suspend/Delete/Expiration
When a guest user is deleted from the system, the RADIUS sessions   associated with that guest user still exists.
Workaround   Reissue the Change of Authorization using the   session information from Monitoring reports for the sessions associated with   that guest user.
http://www.cisco.com/en/US/docs/security/ise/1.1.1/release_notes/ise111_rn.html#wp411891
from BUG Toolkit there is Release-Pending in "Fixed-in" option.