hide login username from the login screen in Fedora 18

I using Fedora 18 - Gnome 3.6.2

I have ten user accounts (created for testing purposes) i dont want the username listed or shown to anyone trying to login to my laptop.

i came across a solution updating gconf database

go to


 touch or create a file called 01.mysettings

vi 01.mysettings

update the dconf database