We currently have SE 1112 and are using two (one primary, one backup). I recently upgraded my primary from 126.96.36.199 to 188.8.131.52 and had some issues after the upgrade.
After some time, the ACS would stop responding via the GUI or just be extremely slow. During this time, I couldn't log in to any devices. I would reboot the ACS and then I could authenticate again.
After looking through the logs for the time the ACS was non responsive, I saw no failed authentications. I saw no failed authentications in the backup server either. After some time the server was extremely slow again (doing anything on the GUI took forever) and I couldn't log in to anything. I decided to power it off. After this, I had no problems authenticating via the backup server.
I upgraded exactly how Cisco said. Upgraded the management software, then the acs software, backed up my database, ran the recovery disk for 1112 184.108.40.206, recovered my database.
I haven't uploaded any of the patches, but I don't see a description any where for this bug.