Outgoing mails should be in UTF-8 encoding.

I don't know why but forward modules sends mails using iso-8859-1 character encoding. I think it should use UTF-8 encoding.

On line 564 in /* $Id: forward.module,v 1.11.2.5 2006/03/27 21:59:18 seanr Exp $ */
On line 557 in /* $Id: forward.module,v 1.11 2006/03/10 00:24:03 seanr Exp $ */

$headers .= "Content-type: text/html; charset=iso-8859-1\n";

should be replaced with

$headers .= "Content-type: text/html; charset=utf-8\n";