Sent to me by our IT guy. I hear this may be old news now, but...whatever...
The resolution for the smb authentication is because panther can not send digital signatures with its authentication
Windows 2000 and windows 2003 active directory domains can not .successfully authenticate so you need to edit the registry on all of your domain controllers and servers that will be accessed by the Mac Clients.
The Key is in
hkey local machine
system
current control set
services
Lanmanserver
Parameters
Requiresecuritysignature
Set it to 0
Save and exit reboot the server
This will make it all happy!
This isn't the case with Jaguar however. J