linux1.hostingmatrix.net has no MX records.
Question and response
Question
dig linux1.hostingmatrix.net. MX
Answer
The response has no answer records.
Authority
hostingmatrix.net. 300 SOA ns1.hostingmatrix.net. hostmaster.sitelingo.com. 1327688020 3600 300 1814400 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0