mailerdaemon — set the From: address for MDNs
MailerDaemon = "mailer-daemon@hostname"
When sending bounce messages upon a permanent delivery failure of a message, the recipient is specified as the original sender, the envelop sender is null, but the "From:" header is dictated by Momentum as "mailer-daemon@hostname" where hostname is the hostname of the local machine, as returned by
gethostname . Alternatively, it can be explicitly set using this option.
mailerdaemon is valid in the binding, binding_group, domain and global scopes.