[Samba] Is there a way to allow empty user (NULL) to connect to samba3 as nobody/guest from W2K/XP workstations?

[Vlad Borisoff]

Hi,

After   switching  to  samba3  I've  noticed  that  it  doesn't  allow
connections  with empty usernames with security = user anymore.
Samba2  mapped  empty  user  to nobody, is there a way to achieve such
behavior?  It  is needed for compatibility - we still have lots of W2k
workstations  that  allow passing empty usernames in login prompts (as
opposed to XP).

Adding null/NULL to smbusers file didn't help.
Searching documentation & googing didn't give me an answer for this issue.
-- 
Thanks in advance,
Vlad Borisoff