lab.scc-zip.net has no MX records.
Question and response
Question
dig lab.scc-zip.net. MX
Answer
The response has no answer records.
Authority
lab.scc-zip.net. 86400 SOA ns1.scc-zip.net. dnsadmin.scc-zip.net. 2013050280 28800 7200 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0