Roll back to the previous OS version. If the problem goes away, then you've found a bug in the OS. That's a risk you run with any new OS version, leaked or official. If the problem doesn't go away, then something else you changed is causing the problem. Have you installed any new apps?
Yes. Do a clean 246 install and rebuild the device on that load. This is an app permissions problem most likely seen with Google Maps at least that is the most common for me.
Posted from my CrackBerry at wapforums.crackberry.com
1. Wiped my entire device, retained .246.
2. Did a selective restore, unchecked - permissions, firewall
3. In application manager - manually allowed permission for all, and the security timer permission wasnt greyed out this time around.