qa-reports.gentoo.org has a link in the rightmost column ("Ebuild Problems") for Non-fetchable distfiles that leads to http://dev.gentoo.org/distfile-mirroring/ which is now a 404: The requested URL /fcgi-bin/gorg.fcgi/distfile-mirroring/failure.xml was not found on this server.
These reports generated GuideXML which no longer works.
*** Bug 592058 has been marked as a duplicate of this bug. ***