Lock Screen and Screensavers

Hello,

I am having a issue with being able to lock the screen or setup a password
protected screen saver in Gnome under RH 7.2. When I go to the menu and
click on "Lock Screen", nothing happens at all. So I thought I would setup a
password protected screen saver with a very short timer. However, that does
not work either, the screen saver just never starts whether it is password
protected or not. If I click on preview it starts just fine, but it will not
start on the timer. Can someone help me out with either of these? Thanks!

Adrian