dovecot - Aug 2008 - Has anyone ever seen outlook do single sign on with dovecot/etc?

Hey all,

I'm curious, has anyone been able to get outlook to do single sign on
with a linux IMAP/SMTP back end? I have it doing NTLM authentication
via the dovecot winbind module with Samba 3.2 just fine, but I have
yet to see it try to use the cached windows logon credentials.. It
appears to do an NTLM exchange with a blank password and then prompt
for a password and then do an exchange with the given password. It
does the same thing if PLAIN authentication is used.

I'm starting to suspect MS deliberately hobbled outlook so that it
uses the SSPI to exchange an entered password but not ever the logon
credentials.. Does anyone know different?

What a topsy-turvy world when thunderbird using SSPI works better on
Windows than outlook. :|

Thanks,
Jason