samba - Jul 2011 - Cross-realm authentication

Hello,

I created a cross-realm between a Kerberos MIT and a AD 2008 R2. That works.
I can authenticate a MIT user from a windows workstation. I configured a
samba workstation and add it into my Windows domain. I can authenticate a
user form my AD but not from MIT Kerberos. How can I do that ? Is it
possible ?

Thanks