Outlook 2007: Outlook profile for users with mandatory profiles.

We are operating a Windows 2003 AD domain where the client machines are
running XP Pro SP3, the DCs are Server 2008 (64) and Exchange server is 2003.
Most of our users log on with mandatory profiles. We've configured these
profiles to import an Outlook PRF profile from the netlogon share on the DCs.
This is done through a ImportPRF string in the following registry location:
HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\O utlook\Setup
For the most part, this seems to work well; however, there are some users
whose profiles don't seem to be successfully copying over the profile. There
doesn't seem to be any pattern to this. Some users will only have the default
Outlook profile loaded, which simply picks up the user settings that were
used to initially configure the mandatory profile. Some users do actually
pick up the correct Outlook profile that we've configured, but Outlook
crashes upon opening (Outlook has encountered an error. The Outlook window
could not be opened.). If we open the Mail applet from Control Panel and copy
the Outlook profile (the one we configured) and rename it (adding a 1 to the
end of the name), the profile will work fine. There are no errors generated
from these events and we are finding it difficult to troubleshoot the issue.
Any ideas anyone? Thanks,
Adam