There's a comment "# Unknown item missing from deps, gtkunique." in gthumb's ebuild, I guess that means the newly added libunique.. Might as well make use of it?
if the API didn't change too much, it could yes.
2007-08-18 Paolo Bacchilega <paobac@svn.gnome.org> * configure.in: * src/Makefile.am: * src/main.c: * src/gth-window.c: * src/gth-application.h: * src/gth-application.c: * src/GNOME_GThumb.idl: * data/Makefile.am: * data/GNOME_GThumb.server: Use again bonobo to provide the single instance application feature. Removed the gtk-unique dependecy as it's not well maintained, api unstable, poorly available, not enough powerfull.