Установил последнюю бету server light и обновил до t6.
Раз в сутки начал получать письма:
/etc/cron.daily/stmpclean: line 5: stmpclean: command not found
/etc/cron.daily/stmpclean: line 7: stmpclean: command not found
/etc/cron.daily/stmpclean: line 10: stmpclean: command not found

хотя
[root@ca44 ~]# rpm -qf /etc/cron.daily/stmpclean
stmpclean-0.3-alt3

[root@ca44 ~]# rpm -ql stmpclean
/etc/cron.daily/stmpclean
/usr/sbin/stmpclean
/usr/sbin/tmpwatch
/usr/share/doc/stmpclean-0.3
/usr/share/doc/stmpclean-0.3/FAQ
/usr/share/doc/stmpclean-0.3/README
/usr/share/man/man8/stmpclean.8.gz
/usr/share/man/man8/tmpwatch.8.gz