Recently installed SLES10 64bit on 2 servers, default Gnome - when using the 'Lock Screen' feature the screen dims and goes blank and I would expect it to lock the screen and session but it doesn't - how can I change this?

With KDE, lock, well locks it until you enter a password, I was expecting the same with Gnome, and the icon does show a key.

BTW - SLES10 with KDE does lock as one would expect, Gnome doesn't for some reason.

This is very frustrating, and nobody has been able to offer a fix on other forums.