One of the main features introduced in the iOS 5 was iCloud which help you to backup and restore your device wirelessly so you can avoid the usage of iPhone Sync Cable. The best use of the service comes when you can easily backup and restore your device from iCloud Backup service rather than on Local PC or Mac using iTunes.
These cloud services are working perfectly for us, but there may be a security Flaw using these services for restore process. Guys over Electronista came across with a problem which is,they started receiving random Apple IDs rather than the original one. According to them, when you do a software restore on your device using cloud backup, it will cause random Apple IDs to be generated on your iDevice.
This problem has also been raised in the Apple's support forum. And according to the Apple's forum, they are working on this problem and soon they will fix it in the next release, iOS 5.0.2. Electonsita has also posted a video which clearly shows that how Apple ID's are generated and shown, even if those Apple ID's doesn't belong to them. And if it disappears, it will start appearing again right after 20 mins.
As there is no solution for this problem, but you can apparently fix it by avoiding the restore using Cloud Backup service. Instead, Do a clean restore using iTunes from your PC or Mac. However, we will need to wait for the release of iOS 5.0.2 to fix this problem.