On Wed, Feb 12, 2003 at 04:06:26PM +0000, robin szemeti said: > most MUA's use the 'References:' or the 'In-reply-to:' line in the header to > do the threading ... off hand I can't think of any that use the subject line
/me coughs and points at http://www.jwz.org/doc/threading.html which lists headers you should look at. I believe Mutt's threading algorithm is based on this technique but I could be horribly wrong. His 5th step is "If any two members of the root set have the same subject, merge them. This is so that messages which don't have References headers at all still get threaded (to the extent possible, at least.)" Read the rest of that step for exactly how to thread based on 'Subject:' -- the test for truth is still quicker than the addition
