[sf-lug] what is the name of the screen (application) that comes up when my laptop wakes from hibernate?

[Michael Shiloh]

it's the one that asks for my password to unlock the screen and has 4 
tabs at the bottom, one of them to log in as a different user.

standard ubuntu with gnome desktop

reason i ask is that ever since i upgraded to koala, this screen and 
everything afterwards has corrupted video, unless i click on the second 
from left button (which i'm pretty sure is the one to change users, 
which i'm pretty sure resets the video card, which appears to fix the 
problem). then i log in as myself and everything is fine.

i'm guessing there was an update to this application which skips 
resetting the video card, at least for my video driver (lenova t60, 
intel 945GM/GMS, 943/940GML)

any tips appreciated, but the name of the application would at least 
help me start my search.