I just restored to stock 4.0.2 and locked my phone (it was repaired and sent back unlocked). I'm going through the regular setup routine and when I try to encrypt the phone, it just reboots and nothing happens. I go to the encryption settings, select "Encrypt this phone" and then enter my PIN. I confirm again once it sees that I'm plugged in and have enough battery, but then the reboot happens and I'm back to the home screen. Anyone seen this? I'm on GSM. I had no issues encrypting on 4.0.1.