[CentOS] Nightly housekeeping/Logwatch periodically not running

I've noticed something strange with a 3.4 test box that is basically 
just sitting here in the lab.  I've got it configured to forward me the 
Logwatch run (which seems to go off at 4:02am by default).  Every couple 
of days, that logwatch run goes missing.  I haven't really dug down to 
find out if the cron job is crapping out or if postfix is dropping the 
report on the floor.  Is anyone else having this problem?  It's a 
completely vanilla 3.4 system with all the latest patches on a single P4 
3.4ghz machine.  Otherwise, the system seems to be just dandy.  It's 
quite speedy and has never given me an instant of trouble.

*scratching my head*

Cheers,

C