[Spambayes] Problems with classifying as spam

[skip at pobox.com]

    Jesse> SpamBayes doesn't follow links (see
    Jesse> http://spambayes.sourceforge.net/faq.html#will-show-spam-clues-notify-a-spammer-that-i-opened-their-message
    Jesse> for a tangentially related discussion), ...

Unless you set the experimental x-slurp_urls option to True.  Even with this
set it will only slurp under specific circumstances:

     If this option is enabled, when a message normally scores in the
     'unsure' range, and has fewer tokens than the maximum looked at, and
     contains URLs, then the text at those URLs is obtained and tokenized.
     If those tokens result in the message moving to a score outside the
     'unsure' range, then they are added to the tokens for the message.
     This should be particularly effective for messages that contain only a
     single URL and no other text.

Skip