It's look like that the net-libs/libwww dependency is missing for thunar-0.8.0-r3. Reproducible: Always
Looks more like you need to run revdep-rebuild... # emerge -pv thunar libwww These are the packages that would be merged, in order: Calculating dependencies... done! [ebuild R ] xfce-base/thunar-0.8.0-r3 USE="X dbus -debug -doc exif gnome hal pcre plugins startup-notification" 0 kB [ebuild N ] net-libs/libwww-5.4.0-r7 USE="-mysql ssl" 1,118 kB Total: 2 packages (1 new, 1 reinstall), Size of downloads: 1,118 kB