Should double-bounce@mydomain.com be a valid email address?

Our postfix setup uses recipient address verification. Obviously, postfix uses a special email address for this process, defined right here. $ /usr/sbin/postconf | grep double_bounce_sender address_verify_sender = $double_bounce_sender double_bounce_sender = double-bounce Last week we got a problem with this setup, as our smtp asked the target smtp about the recipient address, the target smtp on the other hand, asked our smtp, whether double-bounce@mydomain.com is valid, which it neglected. So, that email could not be delivered, although both the original sender and the recipient are valid email addresses. Now, I have different options: * deactivate address verification * create an alias for double-bounce@mydomain.com, so it gets valid * set another valid email address/alias as double-bounce address I can't foresee the outcome of these actions. Any thoughts?