'dev-qt/qtgui:4[dbus(+)]' is wrong, latest qtgui ebuild does not have qtdbus dep now, see https://bugs.gentoo.org/show_bug.cgi?id=478222#c4
+ 28 Sep 2013; Daniel Pielmeier <billie@gentoo.org> backlite-1.0.3-r1.ebuild: + Depend on dev-qt/qtdbus. This fixes bug #484162. Thanks to Nikoli for the + report.