Theres an XSS issue with bugzilla's atom feeds: http://www.bugzilla.org/security/2.20.3/ Please upgrade to 2.22.2. This version also fixed mysql compat issues with newer mysql versions: http://www.bugzilla.org/releases/2.22.2/release-notes.html
New packages with 2.22.2 built in FC-5, FC-6, devel.
Succeeded by https://bugzilla.redhat.com/show_bug.cgi?id=239786#c3.