CRON and SMTP

[szumlins]

Okay, I have 2 questions. First, I just added a bash shell script to cron 
that runs every half-hour. It works great, but unfortunately it sends an 
e-mail to root every half hour as well confirming the tast being 
complete. This means I get 48 identical e-mails daily. Anyone know how to 
turn off logging for that particular script? it is running off a crontab 
script in one of my users home directories. It is looks like this:

     [root@britney ak]# more crontab
     6,42 * * * *       /home/ak/stats

where "stats" is the shell script. I just don't want to get e-mails every 
30 hour saying the same thing, only when an error occurs in the running 
of the crontab.

Second, I can't seem to let my e-mailer on my Mac send mail through my 
mail server. Pine works perfectly, but I have tried Netscape, Outlook, 
and my Mac e-mailer, all give back the same message when I try to send:

      ** 550 relaying to <blah@blah.blah> prohibited by 
      administrator (failed to find host name from IP address)

      ** SMTP server error "503 Valid RCPT TO <recipient> must precede 
      DATA"

How do I allow hosts other than my server itself to use the server for 
sending mail? I'm using exim, btw.