in the WA_Universal Email folder, open each of the files whose name begins with WAUE_
on line 15:
$WA_MailObject = WAUE_Definition("".($WAGLOBAL_Email_Server) ."","25","","","","");
change that to:
$WA_MailObject = WAUE_Definition("".($WAGLOBAL_Email_Server) ."","25","","","","UTF-8");