dns4.wanadoo.es has no MX records.
Question and response
Question
dig dns4.wanadoo.es. MX
Answer
The response has no answer records.
Authority
wanadoo.es. 3600 SOA dns1.wanadoo.es. hostmaster.wanadoo.es. 2012012738 14400 3600 2592000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0