These two fields allow to specify a different default assignee for ticket opened against this package in bugzilla. Note: The EPEL field is always displayed for packages in the 'rpms' namespace regardless of whether it is used in bugzilla or not.
YafaRay may crash with some versions of gettext (bugzilla #650471). As a workaround, running "qtconfig-qt4" and changing the style from "GTK+" to "Plastique", fix the problem (at least in KDE).