Netqmail can not be installed due to a file collision. The detected file collision is with /usr/share/man/man3/error.3.bz2. portageq / /usr/share/man/man3/error.3.bz2 sys-apps/man-pages-3.18 (similar to bug #177605, mail-client/mutt-1.5.15-r2 & net-mta/netqmail-1.05-r8 collision)
Please don't CC maintainers/herds yourself. Leave that to the bug-wranglers.
*** This bug has been marked as a duplicate of bug 137207 ***