At long last, a problem I've ignored for many, many months is revealed and resolved. Apple gives this simplistic view of a Mac connecting to an SMB share on a windows file server (Win 2003):
http://support.apple.com/kb/HT1568
Which says, select Go > Connect to Server
type in
smb://servername/sharename
enter your domain/username/password
and voila! You are in the land of the MS clients now.
But alas, this failed, and Apple contractors on the net couldn't connect.
So I tried to connect to a member server using this method, with a local account instead of a domain account, and that DID work.
So I thought, Domain Policies, perhaps, and a quick Google turned up this completely useful link:
http://allinthehead.com/retro/218/accessing-a-windows-2003-share-from-os-x
Which says, basically, that by default a Windows domain policy will require all connecting clients to digitally sign communications, which Macs don't do, and thus, lost in translation.
Disable this policy (see link above), run gpupdate to refresh the domain policy, and away we go.
