>Is there any reason that the _AUTOLEARN_ tag isn't getting replaced with "no", "ham", or "spam"? Or is there something with my distribution's setup that's causing this?
If report_safe is not set to 0, SA won't do that, it will only honor _SCORE_ and _REQD_.
Read the documentation for rewrite_header in man Mail::SpamAssassin::Conf.
Self correction, I was quoting documentation for SA 3.0, and you're apparently using 2.6x. (In the future, when asking config questions please specify what version of SA you're running, particularly if it's not the latest)
In any event, read the documentation for subject_tag in man Mail::SpamAssassin::Conf if you're using 2.6x. It works much like 3.0, however, the docs seem to read the reverse, claiming you can only use SCORE and REQD unless report_safe is used. I suspect this is a typo, and it means unless report_safe 0 is used.
