mx.zorveta.com has no NS records.
NS records for this zone are defined at zorveta.com.
NS records for this zone are defined at zorveta.com.
Question and response
Question
dig mx.zorveta.com. NS
Answer
The response has no answer records.
Authority
zorveta.com. 3600 SOA dns.zorveta.com. hostmaster.zorveta.com. 1345839288 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0