kdesktop_lock in kdebase before 3.1.3-5.11 for KDE in Red Hat Enterprise Linux (RHEL) 3 does not properly terminate, which can prevent the screensaver from activating or prevent users from manually locking the desktop.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10535
http://www.securityfocus.com/bid/19152
http://www.redhat.com/support/errata/RHSA-2006-0576.html
http://securitytracker.com/id?1016571