Nachdem ich /etc/motd manuell angepasst habe, sehe ich nun für die mailer.conf folgenden Eintrag:
The following changes, which occurred between FreeBSD 10.0-RELEASE and
FreeBSD 10.1-RELEASE have been merged into /etc/mail/mailer.conf:
--- current version
+++ new version
@@ -1,5 +1,6 @@
+#...