idunn.t-mobile.cz has no MX records.
Question and response
Question
dig idunn.t-mobile.cz. MX
Answer
The response has no answer records.
Authority
t-mobile.cz. 3600 SOA tmobile1.ns.nic.cz. dss-system.t-mobile.cz. 1771550598 43200 3600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0