Philip and I had some time getting the client authentication working in the lab today. We could browse the LDAP directory from the client using GQ, we could see the LDAP users from Yast's users and groups pane, but they weren't showing up on the login screen.
Browsing around the net, I found a couple of sites reporting problems which reminded me that errors like this can be tracked down from /var/log/messages. The message I was getting was "kdm: ldap_pam: bla bla (Protocol Error)". After calling in some help from various mailing lists, and comparing our configuration to a working configuration (always helpful), I changed the LDAP version in /etc/ldap.conf from version 2 to version 3 later realizing that the same affect could have been achieved by un-checking the "Use LDAP version 2" box on the pane provided in Yast->Network Services->LDAP Client.
