If a an SMTP error happens when a user clicks send the user is shown an error message. Would it be possible to include the SMTP error given from the SMTP server in this error message? Or maybe have a config option to enable such behavior?

Although I do not expect users to understand the SMTP errors, but when users generate support cases when problems occur with our SOGo webmail solution it would be very beneficial to us if the user could give us the SMTP error they experienced.

Example of such errors could be that the user has reached his or her quota for sending mail, there is a formatting problem with the mail, the mail has too many recipients or any other problem the SMTP server might report.