No cron on SuSE 8 ?! (OT for security)

Hi, I wonder if there are any problems with cron on SuSE 8. None of my cron scripts work. It seems that they don't even start. I also put a simple command in my crontab (5 * * * * echo "Cronjob" | mail -s "Mail from cron" root). This doens't work, too. Why? Cron is running, the cronfiles are in /var/spool/cron/tabs. In messages I see that cron recognized that I modified/listed the crontabs. But nothing else. None of the users is listed in cron.allow (doesn't exist) and cron.deny. Any idea? Thx, Oliver