[Samba] A few questions

[Shane McBride]

1. There is no Domain Users group on my Samba 3.0.6 server. Does this 
group need to be manually created?

2. In my smbpasswd file:
# Unix_name = SMB_name1 SMB_name
root = Administrator
nobody = guest pcguest smbguest

I can not join a domain using administrator. I must use root. What did I 
do wrong?

3. Since there is no Domain Users group. I have been adding each user to 
the admin group on the local PC. When they are added the security 
identifier is also shown. How come?