I have a 5.0 install that has upgraded to 5.1. since the initial install, I've never had the password prompt come up for getting back into the machine after locking. I verified that I do have locking turned on, and my account requires a password to login.
When locking, the screen will go to a lockscreen (after a long wait), but when I return and move the mouse or hit the keyboard, I'm immediately returned to my running session...no password needed.
While some would call this a feature, I kind need to be able to lock my screen. Any thoughts?