_spf0.sapo.pt has no MX records.
Question and response
Question
dig _spf0.sapo.pt. MX
Answer
The response has no answer records.
Authority
sapo.pt. 3600 SOA ns.sapo.pt. root.sapo.pt. 1771869106 3600 7200 2419200 300
Additional
The response has no additional records.