ftip006236892.acc4.mr.21cn-nte.bt.net has no MX records.
Question and response
Question
dig ftip006236892.acc4.mr.21cn-nte.bt.net. MX
Answer
The response has no answer records.
Authority
acc4.mr.21cn-nte.bt.net. 86400 SOA ns0.bt.net. hostmaster.bt.net. 8286 10800 3600 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0