Custom logonprompt text doesn't appear

In previous Windows versions a custom text could be set in registry values:

HKLM\Software\Microsoft\Windows NT\WinLogon\Welcome
HKLM\Software\Microsoft\Windows NT\WinLogon\Logonprompt

that would appear as the title and within the login box. In Vista Business
SP1 these texts aren't displayed on any logon screen that I can find.

The values is in the real registry, put there either by group policy or by
an administrator in elevated mode.

Can't believe it's a whole year later and this isn't corrected in SP1. I
found one web reference that suggests this should work, but here's a
reference from September that says it doesn't work:
http://forum.soft32.com/windows/Cust...ict354316.html

What am I msising? Only been a Vista user for a week and my list of things
that don't work from XP is growing at an alarming pace. I had much greater
hopes for SP1...

Carl