I've tried to set this up a couple times and somehow I get no banner 
display at all.

On an idle desktop I set the following by running dconf-editor as root, 
made sure the system was up to date (SL7.1) and rebooted it. When the 
login screen came up all I get is the two most recent users listed.  No 
banner at all.  So it's not showing the banner and it is showing the 
recent user's.  I've looked into this issue a few times but never found 
a solution, so it's probably something really simple and silly that I'm 
missing.

[org/gnome/login-screen]
banner-message-enable=true
banner-message-text='You are accessing a U.S. Government (USG) 
Information (...snip...)'
disable-user-list=true
enable-fingerprint-authentication=false

-- 
Stephen Berg
Systems Administrator
NRL Code: 7320
Office: 228-688-5738
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