Fedora 14 Login screen not shows users

edit

Hello Guys

I using F14 (i know it is running out of support) on a Thinkpad T60. At latest install I set up a LUKS encryption to whole Physical Volume in lvm (Company requirement)

After this install I found that in the GDM login screen I couldn't get usernames. After a successfully login and logout, it show the users.

If somebody know why it works as I described, and how could I set the login screen to show my id at first login, please let me know.