ip.onefone.pl has no MX records.
Question and response
Question
dig ip.onefone.pl. MX
Answer
The response has no answer records.
Authority
ip.onefone.pl. 3600 SOA localhost. root.localhost. 1755586002 7200 1800 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0