27Apr/090
Cannot join OpenSolaris CIFS service to Windows 2008 Domain
By default, our redirector uses NTLMv2 authentication. Prior to joining
your system to a Windows 2008 domain, please run the following command
on your Solaris system such that NTLM authentication will be used instead:
sharectl set -p lmauth_level=2 smb
This is a known issue with Windows Server 2008 which by default
disallows NTLMv2 authentication if the client doesn't support extended
security. Microsoft is working on a hot fix for this issue. Once it
becomes available, the above workaround will no longer be needed.
Reference: http://www.mail-archive.com/cifs-discuss@opensolaris.org/msg00170.html