If you want to take a look at it, I uploaded my working version to https://sourceforge.net/tracker/?func=detail&aid=2979323&group_id=311&atid=423692 (and submitted to Paul).
We may compare our modifications and merge it into a new release.
http://squirrelmail.org/plugin_view.php?id=62 won't work with my
squirrelmail (currently 1.4.20), and since the plugin is quite old
(2003 ?) I took a small look into the code. With a few changes, I was
able to make i t work again. Any Idea of where I should direct a patch
to the code, so squirrelmail can again fight the evil winmail.dat and
TNEF encoding hell.