[TriLUG] crond opening root sessions..?

[Brian Henning]

Hi Folks,
   Past couple days I've started seeing entries in the pam_unix section 
of LogWatch that look like this:

crond:
    Unknown Entries:
       session closed for user root: 270 Time(s)
       session opened for user root by (uid=0): 270 Time(s)

I don't know what that means, or why it's suddenly happening.  crond 
opening a session for user root?  A session of what?  When I hear 
"session," I think "interactive," and nothing that cron is doing should 
be involving interaction from anyone.  root's crontab just has what I 
expect it to have.

The only thing I've changed lately was to install the MailScanner RPMs, 
but I haven't actually put the installation to work; haven't configured 
it, haven't stopped sendmail and put mailscanner in control, etc.

So it's got me a bit nervous.  Could something nefarious be going on 
here?  Why should root be opening a session a little more than 11 times 
an hour?

Thanks,
~Brian