Hello, a customer of mine is using "Avira Managed E-Mail". We're using the mx-records for Avira. Everything works fine so far, but web.de and GMX answer with Nemesis ESMTP Service not avail able 554-No SMTP service 554-Bad DNS PTR resource record. 554 For explanation visit http://postmaster.web.de/error-messages?ip) After talking to Avira, they told me that the Reverse-DNS have to match "customerdomain.com", not "myserverprovider.com". To fix this, I bought another IP @ Hetzner and included everything - it works fine. But I get "Reverse DNS does not match SMTP Banner". Is it possible to answer with a IP-Based $myhostname?