Mail filter seems to mark outgoing mail as spam...is that right?

Question

I thought that the mail filter ran on incoming email before it got delivered to individual mailboxes.
But I have a php program that uses my smtp server to send email (using the php mail() function). Recently one of the accounts we were testing, sent several empty email messages to test accounts. This caused the spam filter to classify it as spam. But the weird part is it gets tagged with my spam message in the subject when it gets sent.
I can understand it being marked as spam to my local email accounts, but when it is marked by my custom spam filter message in my gmail inbox that is amazing.
I'm just surprised that it is going through the filter on the way out. Does this sound right?
Is there a configuration that prevents this?
xserve Mac OS X (10.4.7)

Answer 1

It should be good enough to redirect (not forward) mails originating from that account to "notjunkmail". May take more than one redirected mail though.
You can however whitelist domains or accounts which is easier than avoiding outgoing scans. However, whitelisting by domain or mail address always bears a risk of letting "spoofed" mail through. So if you go down that route, make sure your server is properly secured.
Check /etc/amavisd.conf
It is full of examples on how to customize it (including whitelisting). Look especially at section V
It's quite well documented. If you have problems, post back and somebody will help.
Alex