xorg 6.8.0 requires the xprint use flag for several programs to work - mozilla*-bin requires it, as does acroread, and most likely other programs. I notice that the default-x86-2004.2 profile _does_ have xprint specified in make.defaults, but default-linux/x86/2004.2 does not. xprint and bitmap-fonts need to be added to at least the default-linux/x86/2004.2 profile, and most likely to other (cascading) 2004.2 profiles.
yeah, we're aware of it
should be fixed as of yesterday (in a solution that is definitely not cascading, unfortunately, but portage 52 should fix that).