Scanelf shows: dev-libs/atk-1.32.0-r1 dev-libs/dbus-glib-0.98 dev-libs/glib-2.30.2 dev-libs/libical-0.48 dev-libs/popt-1.16-r1 media-libs/fontconfig-2.8.0-r1 media-libs/freetype-2.4.8 sys-apps/dbus-1.4.16 x11-libs/cairo-1.10.2-r1 x11-libs/gdk-pixbuf-2.24.0-r1 x11-libs/gtk+-2.24.8-r1 x11-libs/libX11-1.4.4 x11-libs/libnotify-0.7.4 x11-libs/pango-1.28.4 xfce-base/libxfce4util-4.8.2 xfce-base/xfce4-panel-4.8.6 please check and update rdep
it has everything, rest is result of overlinking or the way GTK+ is built against specific libraries