Code:
telnet mail.maisveloz.com.br 25
Trying 200.186.145.138...
Connected to mail.maisveloz.com.br.
Escape character is '^]'.
220 mail.maisveloztelecom.com.br Microsoft ESMTP MAIL Service, Version: 6.0.3790.3959 ready at Sat, 3 Jan 2009 20:52:50 -0200
if you are expecting to receive external email on the above domain then you need to update your external DNS MX record.