FC 3: Every cron job logged to messages

I just upgraded my FC2 system to FC3.  Now the following is logged to
/var/log/messages every time a cron job runs (filling up my messages log
with unhelpful cruft):


Dec 17 10:01:01 hostname crond(pam_unix)[15548]: session opened for user
root by (uid=0)
Dec 17 10:01:01 hostname crond(pam_unix)[15548]: session closed for user
root


I suspect this has to do with cron now using PAM in FC3.  Is there a
clean way to silence this?


Thanks.

Andrew