When I installed Ubuntu 11.10, I had a single monitor attached to it. The screen was locking perfectly fine.
Since then I connected two monitors to the system and replaced video card to another brand.
All seems fine except for screen locking not working anymore. When you go to lock settings, all are there, but the screen just does not lock. You can lock manually, though. I tried to disable locking, then restarted, and re-enabled it. Still no luck.
Any suggestions would be greatly appreciated!