Samba 4 - very long login time on Windows 7

[fatman at crackmonkey.us]

Hi list!

I'm happy to report great success with Samba 4 alpha 15 on Ubuntu Lucid
LTS with two Windows 7 Ultimate clients. :D

I notice though that my two workstations are taking ~10 minutes to log
in. On both systems, Event Viewer shows event IDs 6005 and 6006 each
occurring twice during login.

6005 is "The winlogon notification subscriber <x> is taking long time to
handle the notification event (Logon)", where x is Profiles in the
first instance and GPClient in the second on both systems.

6006 is "The winlogon notification subscriber <x> took y second(s) to
handle the notification event (Logon)", where x is Profiles in the
first instance and GPClient in the second on both systems, and y varies
but is around about 90 seconds in the first instance and 300 in the
second.

Do we know how to fix/workaround this? My Google searches suggest it
might be a Windows issue. I should add that I'm not running any login
scripts, and running "gpresult /Z" on both systems returns "the user
does not have RSOP data".

Is there a log file I can check on my Ubuntu DC?

TiA,
Adam J Richardson