Personally don't have much motivations to see internatlized explanations
(you're sending explanation to somebody else, who you dont know, nor do
you know what language they speek, better pick closest to semi-international
language there is in the world>.
But if there is serious interest to do it, I recommend doing it the same
way its been done to support multiple charsets for Subject and From
and other headers. For more info see http://www.ietf.org/rfc/rfc2047.txt
--
William Leibzon
Elan Networks
william(_at_)elan(_dot_)net