My crontab only likes five asterisks (timezone related?)

So the question now is:

It's evident that the cron daemon is working with the old timezone while the rest of the server is working with the new timezone.

How can I fix the cron daemon's understanding of the new timezone?

My guess is the a timezone data update package has been installed (tzdata RPM or similar) but the server has not been rebooted and the crond daemon has not been restarted after the update, so crond is still using the old timezone data it loaded when it was originally started.

If that is the problem, then restarting the daemon should fix the problem, as Shane H commented: service crond restart or /etc/init.d/crond restart should do it. You should also consider restarting any other long-running system daemons that may record timestamps, like sendmail.