NB> Am I missing something easy here?

   I think so.

 NB> --- Mystic BBS v1.10 A20 (Linux)

   In the linux version of (at least) Thunderbird, you shall not hit the reply
button -- it will try to send an email reply -- but rather the button to the
right of that (totally forgotten what it says).

--- Mozilla/5.0 (Windows; U; Windows NT 5.1; sv-SE; rv:1.9.1.16) Gecko/20101125