For multi-homed servers, this may cause confusion and prevent clients from connecting to the server.
In OS X Server (Mountain Lion) or Lion Server, use this command to restrict DDNS registration to a single interface (en0 in this example):
dsconfigad -restrictDDNS "en0"
For Mac OS X Server v10.5 or v10.6, edit the /etc/smb.conf file.
After the line "; END required configuration.", specify the interface(s)/address(es) that you do want registered after 'interfaces =': .
interfaces = en0
bind interfaces only = yes
This will cause Samba to only bind to the specified interface(s) and only register the selected interface(s) address in DNS. This information is from samba.org, attributed to Tim Potter.