fortune-mod-1.99.1-r2 installs the symlink /usr/share/man/man1/unstr.1.gz -> strfile.1.gz but it is broken - unless the system happens to have manpages compressed with gzip, I guess. FWIW, I have PORTAGE_COMPRESS="". Reproducible: Always
This is fixed in git: http://git.overlays.gentoo.org/gitweb/?p=proj/portage.git;a=commit;h=700a5b19b310e805800dcef5730e8244115e774f
This is fixed in 2.1.11.60 and 2.2.0_alpha171.