This bug has been copied from bug #615179 and has been proposed to be backported to 5.5 z-stream (EUS).
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: Previously, 'sudo' returned a 'cache error' whenever a mixed cased user name or a mixed cased group name was fetched from an Active Directory via LDAP (Lightweight Directory Access Protocol) or QAS (Quest Authentication Services). With this update, the case of a user name or a group name is ignored and 'sudo' no longer returns a 'cache error'.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2010-0777.html