I just noted that it doesn't like UTF-8. On GMail I got the utf character printed right but the mail header contains this which is I assume wrong: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Encoding should prolly be "quoted-printable", but I didn't had my nose in mails for quite some time, I hope some of you will know better than I do.
I forgot an example: http://foo-projects.org/pipermail/xfce/2009-September/025878.html
http://git.xfce.org/admin/xfce-git-hooks/commit/?id=d424099dc1121ca88950cc7fb362d84869425207