Does anybody know the header for sending an 'on behalf of' email. You know when you see an email from someone and it has a behalf of statement in it, how are these sent, it would be good if it was built into the multimailer as a

This is a functionality of the email server (eg MS Exchange).
In its setup you are granted access to read and to send also emails from an other address (mail box) that belongs to someone else (boss, department, ...). In your mail client, you can monitor the emails in this inbox and reply to them. The additional header is then added automatically by the mail server.

maybe you could use
with whatever is calling the mailer

an example:
To change all outbound mail to the current username followed by the XOOPS admin configured 'From' value...
i.e.

Sent on behalf of Earl Wilson by xoopsadmin@xoops.org

Set your language constant in:
\language\english\mail.php

in \class\mail\xoopsmultimailer.php change line 159 to:


Of course you could use a much more elegant/conditional implementation with replyto and more (assign variables within a module and set an if condition in xoopsmultimailer.php ) but I'm not even sure if I'm answering what you were asking so I won't go too deep. The xoopsUser var would need to be included as a global for this example to actually work.