Per https://bugs.freedesktop.org/show_bug.cgi?id=46147 $SUBJECT says it all, fixed upstream in dbus-1.4.20 (confirmed it builds as-is, no need to rebase any patches), or you can cherry-pick the fix available in the upstream bug. This is needed to bring qt5 tech-preview packages to fedora 17.
*** This bug has been marked as a duplicate of bug 856131 ***