mx0.uniserve.com has no MX records.
Question and response
Question
dig mx0.uniserve.com. MX
Answer
The response has no answer records.
Authority
uniserve.com. 3575 SOA domains1.uniserve.com. dns-admin.uniserve.com. 2026021800 7200 1800 604800 21600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0