They depend on Qt4 and upstream changelog lied about port to Qt5.
#--- END OF EXAMPLES ---
+# Andreas Sturmlechner <asturm@gentoo.org> (12 May 2018)
+# Depends on dead Qt4, upstream TRAC and SVN dead. No maint. response.
+# Masked for removal in 30 days, bugs #645418, #591866, #574244.
+net-dns/dnssec-lookup
+net-dns/dnssec-nodes
+net-dns/dnssec-system-tray
+
# Mikle Kolyada <zlogene@gentoo.org> (10 May 2018)
# The upstream is totally dead (the last release is from 2006).
# Does not compile against gcc-6, uses old EAPI=3 (#564998, #644262).