mx.hotel-lintner.com has no MX records.
Question and response
Question
dig mx.hotel-lintner.com. MX
Answer
The response has no answer records.
Authority
hotel-lintner.com. 3600 SOA dns.hotel-lintner.com. hostmaster.hotel-lintner.com. 1377854277 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0