LDAP Module only for Authorization and not for Authentication

Hallo, I have Freeradius 1.1.7 and use it to check user and password with pam module. The pam module uses pam_afs.so library to check in the kerberos IV server. I want to keep this configuration but additionaly to make a check for groups in LDAP. Something like: 1. Authorize Huntgroup-Name== xxx, Ldap-Group==xxx.... 2. Authenticate user + password through pam Can I do authorization with LDAP and then authenticate with pam? Then I don't want to provide any passwords in LDAP. Thay must stay in the kerberos IV server. When I use a remote LDAP-Server, should I configure some special modules during the installation of radius? Thanks. Regards Irina