mx1.smartape.net has no CNAME records.
Question and response
Question
dig mx1.smartape.net. NS
Answer
The response has no answer records.
Authority
smartape.net. 3414 SOA ns3.smartape.net. abuse.smartape.net. 2013041697 3600 7200 2419200 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0