Inspired by a blog post from Adrian Sutton and the comments beneath it I am now documenting how I train Spamassassin from within Apple Mail.
The setup is fairly straight forward but implies that you at least have a working Spamassassin instance running somewhere and know your way around UNIX a little bit. So I’m just going to explain the rough details to get you going.

  1. Switch on the bayes database for SA. On my Debian box this is done via putting the line use_bayes 1 in the file /etc/spamassassin/ After that restart SA (eg. /etc/init.d/spamassassin restart)
  2. Let SA put all your Junk Messages in the folder “Junk” in your IMAP Account
  3. Let Apple Mail put all your Junk Messages in the folger “Junk” in your IMAP Account
  4. Install a little Cronjob to have SA learn Spam from your Junk folder and Ham (=not Spam) from your Inbox. The following is my script:
    echo "----learn spam----"
    sa-learn --spam /var/opt/vmail/*
    echo "----learn ham----"
    sa-learn --ham /var/opt/vmail/*

    Note: those are just 4 lines, the blog just wrapps the two ‘sa-learn’ lines because of limited horizontal space. Of course you have to change the path to the real location of your ‘Junk’ folder.
  5. Last thing to do is installing the cronjob. Mine looks like this:
    0 */4 * * * /path_to_your/script > /dev/null 2>&1

Actually my setup involves learning from 4 different user accounts, who all use Apple Mail just to get more Ham- & Spam-volume faster.
I hope this is helpfull to you. It works perfectly on my server for over a month now.

While searching for an easy way to do server side Spam filtering, so I don’t have to bear with all those spams when looking at my Inbox with Webmail, I found IMAP Spam begone. It’s a python script that scans your Inbox for new messages and hands them to Spamassasin to check their spam status and copies them to a pre-defined folder in your Maildir if it is found to be a spam message. Client side spam filtering is done with Apple Mail on my iBook which works very good for me. So there is a second layer of filtering in place in case something still gets through.

Although is rather old and hasn’t been updatet in about three years it works very conveniently and tags nearly all of my Spams, moves them to my Junk folder and deletes them from my Inbox. The script is called from a cronjob and run every 10 minutes so there is a slight chance that I still find Spams in my Webmail before is able to run and delete them.

The reason I settled for this “external” integration of Spamassasin via is that I didn’t want to mess around with the transport rules of my MTA because of the chance to do something not all users are happy with. With IMAP Spam begone I have an individual solution that works for me without altering the way all the other people experience the mail service.

Below you’ll find the command line options I have running, for further explanations please refer to the projects homepage. --spaminbox INBOX.Junk --spamc --delete --nostats --expunge

Update: Since the ISBG site seems to be down currently, I’ll provide a download link for the script here.