Fedora Users — Lots of crond syslog messages...why?

I had a nice stable FC2 system that been running for ages. I finally decided to upgrade yesterday to FC3 and have now managed to get pretty well everything working again. However, I do have one problem that I just can't find.

I get the following messages occurring every 5min in my syslog:

May 29 10:55:01 tiger crond(pam_unix)[5071]: session opened for user root by (uid=0) May 29 10:55:01 tiger crond(pam_unix)[5069]: session opened for user root by (uid=0) May 29 10:55:01 tiger crond(pam_unix)[5070]: session opened for user root by (uid=0) May 29 10:55:01 tiger crond(pam_unix)[5073]: session opened for user root by (uid=0) May 29 10:55:02 tiger crond(pam_unix)[5069]: session closed for user root May 29 10:55:04 tiger crond(pam_unix)[5071]: session closed for user root May 29 10:55:15 tiger crond(pam_unix)[5070]: session closed for user root May 29 10:55:33 tiger crond(pam_unix)[5073]: session closed for user root

I've looked at crontab and crond and commented out anything that was running at 5min intervals without effect. Is this something that happens on FC3 or is there something still broken? Any pointers where else to look???