Want to ask for acknowledgement of receipt

[Pitmaster]

Hi when I make a new mail I want the user to be able to ask for an acknowledgement of receipt.
I think I have to do someting with $rcmail_config['mdn_default'] = 0; in main.inc.php? Am I right?

I find it difficult to find good documentation for Roundcube. Is there someone who can help out here?

Thanks, Pit

[SKaero]

If you want the ask for acknowledgement of receipt on by default set mdn_default to 1.