My installation is : Odoo 8 on Ubuntu 14. We have incoming and outgoing mail configured correctly (both tests return 'successful').

We can send new email message to partners by composing new message. We can also receive messages through the incoming mail gateways configured and the mails are redirected to the wright users.

The problem we are facing is that when we reply to a mail received, the reply is not sent and there is no error message. We have configured an outgoing mail gateway with the lower sequence priority. Are we missing something ?