...

The following is based on having at least two addresses (publicaddress@example.com and spam@example.com) trigger the same procmail script. In most vanity domain setups, all addresses are processed by the same procmail script. The script needs to be edited to include your real addresses and domain. You also need to confirm the path for spamassassin and sa-learn, which you can find, after logging into the server, by typing which spamassassin.

#Uncomment the following lines and use tail -f procmail.log to debug
#LOGFILE=$HOME/procmail.log
#VERBOSE=yes
#LOGABSTRACT=all

# Feed redirected spam to sa-learn, and also store a copy in a folder called spam.
# This folder of false negatives could be useful if we needed to rebuild our Bayes
# database in the future.

:0
* ^To:.*spam@example.com

*  < 256000{

   * < {256000
   :0c: spamassassin.spamlock
   | sa-learn --spam

   :0: spamassassin.filelock
   spam
   }

# Send all other mail through SpamAssassin

:0fw: spamassassin.lock
* < 256000
| /usr/bin/spamassassin


# Mail that is very likely spam (>15) can be saved on the server
# (not forwarded), or by moving the # down one line, even dropped
# on the floor.  Note that dropping mail on the floor is a *bad*
# idea unless you really, really believe no false positives will
# have a score greater than 15.  If you want all mail forwarded,
# just add #'s in front of each of these lines:

:0: spamassassin.filelock2
* ^X-Spam-Level: \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*
#/dev/null
almost-certainly-spam


# Forward all mail with a score less than 15 to my non-publicized address 
:0
! privateaddress@example.net

This file is available procmailrc.forward.txt. If you don't currently have a procmail file, you can import this one by entering:

wget http://wiki.apache.org/spamassassin-data/attachments/ProcmailToForwardMail/attachments/procmailrc.forward.txt
mv procmailrc.forward.txt .procmailrc

On your mail client, you'd then likely want to filter mail with a score of 5 or higher (i.e., where "X-Spam-Level: *****") into a Likely Spam folder. False Positives rarely score higher than 15. The advantage of leaving mail with a score of 15 or higher on the server is that it makes it easier to find false positives in the Likely Spam folder without being overwhelmed by hundreds of obvious spam. You can then ManualWhitelist those false positives.

For the mistake-based training, it's critical to redirect (or bounce) the message, rather than forwarding. Forwarding loses all of the critical header information, which is much of what Bayes trains off of. Here are directions for redirecting from different clients. Note that for all redirections, you'll want to clear away all To: and Cc: entries and then add spam@example.com to the To:, in order to avoid resending the spam to another victim.

• AOL's integrated email client: Redirecting mail is not available. (Dave Goldsmith)
• Eudora: Select the message, go to the "Message" menu, choose redirect, fill in the address, and choose send. (Brian Corcoran and Erik Wheeler)
• Evolution: Select the message. In the "Actions" menu, choose the "Forward" submenu (not "Forward message", the "Forward" submenu). Pick "Redirect", fill in the "To" field, and press "Send". (Johannes Ullrich)
• OS/X Mail.app: With the email message open or selected, go to Mail's 'Message' menu and select 'Bounce to sender' or 'Redirect'. If you use this frequently, go to the "View" menu, choose "Customize toolbar", and add a button for "Redirect". (Marion Bates)
• Microsoft Outlook 97: Double-click on the message so it opens in a new window. Click on Tools-Resend This Message. A warning will appear about you not being the original sender of the message. Click Yes. A message window appears. Update the To: field and click on 'Send'. (Dave Goldsmith)
• Microsoft Outlook 2000 & higher: Double-click on the message so it opens in a new window. Click on Actions->Resend This Message. A warning will appear about you not being the original sender of the message. Click Yes. A message window appears. Update the To: field and click on 'Send'. (Dave Goldsmith)
• Microsoft Outlook Express: It does not appear to have a redirect option. (Dave Goldsmith and Alex Bates)
• Netscape Communicator 4.x and 7.x: They don't appear to have a redirect option.
• Pine: For a single message, highlight the message and press "b" to bounce it. Enter the target address and press enter. For multiple messages, select all the messages you'd like to bounce with either ":" to select them one at a time, or ";" to select multiple messages by message number, subject, body text, etc. Once selected, press "a", then "b" to Apply the Bounce command to all of them. Enter the target email address. Once done, press ";", then "a" to Unselect All selected messages. More can be found at: http://www.itc.virginia.edu/desktop/email/pine/bounce.html
• Sylpheed: Click on the message, go to the "Message" menu, choose "Redirect", fill in the "To:" address, and press send. Alternately, right click in the message and choose "Redirect" from the popup menu, fill in the "To:" address, and press send. (Dave Goldsmith)
  

Thanks to William Stearns <wstearns@pobox.com> for this redirection \[http://www.stearns.org/doc/spamassassin-setup.current.html<ac:structured-macro ac:name="redirect" ac:schema-version="1" ac:macro-id="420ff471-e88d-45f2-8e6b-cba87470db56"><ac:parameter ac:name=""><ac:link><ri:page ri:content-title="info]." /></ac:link></ac:parameter><ac:parameter ac:name="location"><ac:link><ri:page ri:content-title="info]." /></ac:link></ac:parameter></ac:structured-macro>

Contributors

...

See ResendingMailWithHeaders for details of how to do this.

Step-by-step instructions

Way more detail on how to do this is at SingleUserUnixInstall.

Other training options

An even easier form of mistake-based training is to use IMAP and create a Learn{{`As}}`Spam folder, as described in the IMAP section of SingleUserUnixInstall.

Contributors

• DanKohn