Linux box Authentication to Active Directory

I have just bought a server which is pre-installed with SUSE linux Enterprize server version 10.

We have an Active Directory where all the uses are authenticated via it.

I have this linux box which needs to communicate to the windows active directory box.

I have managed to install
-samba
-kerberos
-winbindd
commands used to confirm?
wbinfo ?u
wbinfo ?g
kinit username test
it also ask me for a password.

I have used the above commands in the suse linux box and it gives me the list of users and also groups from my active directory.

This way i confirm that my suse linux box is talking to active directly.

PROBLEM:
Single Sing-on problem

When i log out from my suse linux box and log-in using a user from active directory,NOTHING happens.though it gives me the options to choose which domain do i want to connect to.

WHAT DO I DO ABOUT THIS.How do i do futher testing.

Basically i cant log-in(authentication) using linx box to the active diretory.

Can anyone help me please.

Thanks