smtp-gw.brpay.com.br has no MX records.
Question and response
Question
dig smtp-gw.brpay.com.br. MX
Answer
The response has no answer records.
Authority
brpay.com.br. 60 SOA blue. l-adm-dnspagseguro.uol.com.br. 2011011251 1800 600 7257600 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0