In the past, I was able join dual boot (linux,windows) boxes to an NT4 domain,
by modifying the netbios name on the linux side of things using
netbios name = hostname-samba
netbios aliases = hostname
(or something similar to that).  That way, the machine accounts didn't stomp all
over each other.

Now, I'm trying to do the same thing, but with samba-3.0.14a and Active
Directory.  Unfortunately, it doesn't work (in linux using the netbios name trick).
When 
netbios name = hostname-samba
netbios aliases = hostname
is set, 

$ net ads join 
(supposedly) works saying,
Using short domain name -- DOMAIN-AD
Joined 'HOSTNAME-SAMBA' to realm 'DOMAIN.LOCAL'

But subsequently, winbind doesn't authenticate, and testing wbinfo returns errors:
$ wbinfo -t
checking the trust secret via RPC calls failed
error code was STATUS_BUFFER_OVERFLOW (0x80000005)
Could not check secret