Here just the ~x86-keyword is needed: net-libs/libsoup-2.24.0.1 gnome-base/libgnomeprintui-2.18.3 gnome-base/libgnomeprint-2.18.5 gnome-base/gnome-panel-2.22.2 gnome-base/gnome-menus-2.24.1 dev-libs/libgweather-2.22.3 x11-libs/libwnck-2.24.1 x11-libs/libXres-1.0.3 x11-proto/resourceproto-1.0.2 dev-texlive/texlive-langgerman-2008 net-libs/gnutls-2.5.4 media-gfx/gthumb-2.10.10 media-libs/libmng-1.0.10
Done, I deferred gthumb until bug #243206 is fixed.