[Samba] MS ADS Authentication

[Marco]

Dear group,

I have installed Fedora Core 2 with samba, winbind enabled and managed to join 
our ADS as member server.
Using kinit username at mydomain.com I receive a valid ticket an can connect to 
Windows share by smbclient //server/share -k
Now my goal is to use the AD Usernames i.e. username at mydomain.com for Login to 
Linux. 
I can't find the correct PAM settings, so could please somebody help me?

Best regards,
Marco