spf.whservidor.com has no MX records.
Question and response
Question
dig spf.whservidor.com. MX
Answer
The response has no answer records.
Authority
spf.whservidor.com. 1800 SOA ns1.host.uol.com.br. admin.uolhost.com.br. 2015111003 43200 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0