Hi Lito,
as I'm running a mailserver myself I'm a little bit sceptic that no authentification is required - this would then be a open relay - ahh, spammers would be in heaven - so I've done a telnet session to it:
[admin admin]$ telnet mail.cantv.net 25
Trying 200.44.32.43...
Connected to mail.cantv.net.
Escape character is '^]'.
220-rs25s9.datacenter.cha.cantv.net ESMTP Exchange Server 2.236/2.0
220-Vea
http://www.cantv.net/seguridad/email para terminos y condiciones
220-de uso de este servicio, especialmente en cuanto a los requerimientos
220-tecnicos necesarios para que Cantv.net acepte sus mensajes
220 Wed, 17 Nov 2004 15:37:43 -0400
HELO <hidden>
250 rs25s9.datacenter.cha.cantv.net Hello <hidden>
[217.196.72.126], pleased to meet you
MAIL FROM: <hidden>
250 2.1.0 <hidden>... Sender ok
RCPT TO: <hidden>
550 5.7.1 <hidden>... Relaying denied
Connection closed by foreign host
------- end of telnet session ---------
Pls follow Eddy and give it a try
br
Peter