mexne.jp has no MX records.
Question and response
Question
dig mexne.jp. MX
Answer
The response has no answer records.
Authority
mexne.jp. 900 SOA ns0.mexne.jp. root.ns0.mexne.jp. 2470668640 900 3600 604800 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0