mx2.jpj.net has no NS records.
NS records for this zone are defined at jpj.net.
NS records for this zone are defined at jpj.net.
Question and response
Question
dig mx2.jpj.net. NS
Answer
The response has no answer records.
Authority
jpj.net. 3600 SOA blues.jpj.net. root.blues.jpj.net. 97082768 3600 300 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0