Missing charset in email header
Hi, how do I set the charset in email header? We are using TikiWiki 2.4 to send broadcast messages in Chinese. We have set the "Default charset for sending mail" to utf-8 in General preferences. But the email header shows missing charset..
Content-Type: text/plain; charset=""
Content-Transfer-Encoding: 7bit
What could possibly go wrong? Which source files should I check?
Attached is the "original" lib/mail/maillib.php file.
Thanks!