I have Ubuntu 8.04 LTS machine and Windows 2003 AD domain.

I have succesfully set up that I can log in with domain username and password, using domain prefix, like "domain+username".

Upon login to machine it all works first try, however, for some reason when I try to sudo my logged in user, it asks for the password twice every time when I try sudo. It accepts the password after 2nd time, but not the first time.

Once or twice I might think I just keep entering wrong pass the first time, but this is what happens always, any ideas of what's wrong?

pam.conf is empty pam.d/sudo only includes common-auth & common-account, and

common-auth is:

auth    sufficient      pam_unix.so nullok_secure
auth    sufficient      pam_winbind.so
auth    requisite       pam_deny.so
auth    required        pam_permit.so