I have migrated to using systemd timers for everything, removing cron altogether from my machines. There should be no reason to have virtual/cron installed, but kdeadmin-meta pulls in this. I still would prefer to use kdeadmin-meta instead of getting the packages manually in case the list changes, but the RDEPEND has kcron hard-coded in which pulls in virtual/cron and it is an administrative program I do not need. Logrotate's latest ebuild (which is keyworded on amd64) has a +cron USE flag, to which I set -cron. I think the same should be done in this ebuild in the RDEPEND section.
Thanks for reporting. This is fixed in cvs and git now. Please sync in some hours to get the changes. + + 22 Jun 2015; Johannes Huber <johu@gentoo.org> kdeadmin-meta-4.14.3.ebuild, + metadata.xml: + Add USE flag cron, bug #548908. + https://gitweb.gentoo.org/proj/kde.git/commit/?id=1b55fe8045545ab40c3e773a0968103bf48fc6e4
