ip.t-com.sk has no MX records.
Question and response
Question
dig ip.t-com.sk. MX
Answer
The response has no answer records.
Authority
ip.t-com.sk. 3600 SOA ns.telecom.sk. hostmaster.telecom.sk. 2013010911 28800 3600 1209600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0