The KDE 2.0 kdebase packages for Red Hat 7.0 (both the ones in Rawhide and the newer ones off of kde.org) contain a regression in /etc/pam.d/kde to using pam_pwdb as opposed to using pam_stack to allow for alternate authentication methods such as Kerberos, NIS, or LDAP.
Fixed in 2.0.1-4