Please apply the below patch to cron.log.

reason:  vixie-cron has a feature whereby it mails the
stdout and stderr from a cronjob to the user running the
cronjob.  To do this it fork()s, and the child waits until
the cronjob has completed to determine if mail needs to be
sent.  By using killall you end up killing the child in
addition to HUPing the parent.

So, for example, any errors generated while rotating the
logs will be completely lost, rather than mailed to root.
Instead of using killall, send the HUP to the cron parent
directly.

Dean

--- cron.log.orig       Sat Apr 17 10:47:25 1999
+++ cron.log    Sat Apr 17 10:48:23 1999
@@ -1,5 +1,5 @@
 /var/log/cron {
     postrotate
-       /usr/bin/killall -HUP crond
+       /bin/kill -HUP `/bin/cat /var/run/crond.pid`
     endscript
 }