cm.vtr.net has no MX records.
Question and response
Question
dig cm.vtr.net. MX
Answer
The response has no answer records.
Authority
cm.vtr.net. 38400 SOA ns00.vtr.net. hostmaster.vtr.net. 2011061603 10800 3600 604800 38400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0