ns2.arcemus.com has no MX records.
Question and response
Question
dig ns2.arcemus.com. MX
Answer
The response has no answer records.
Authority
arcemus.com. 86400 SOA udns1.cscdns.net. hostmaster.cscdns.net. 2011022713 28800 7200 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0