i have a problem with mailenable in plesk

[alekos]

i have a problem with mailenable in plesk 7.5.3 when i send a mail to a domain for example gmail.com or hotmail.com yahoo.. etc the mail is rejected and postmaster send to the account this information


MailEnable: Message delivery has been delayed.

Message is waiting at computertec.com.ar for delivery to verifier.port25.com.

Reason: Mail Server for verifier.port25.com could not be contacted at this time. MailEnable will keep trying to deliver this message and will notify you of any progress.


Message headers follow:

Received: from localhost ([127.0.0.1]) by domain.com with MailEnable ESMTP; Sat, 19 Oct 2002 01:21:20 -0300
Received: from 200.127.211.134 ([200.127.211.134]) by
webmail.domain.com (Horde) with HTTP for <adm@domain.com>;
Sat, 19 Oct 2002 01:21:20 -0300
Message-ID: <20021019012120.sddmoq2xlwsw88gg@webmail.domain.com>
Date: Sat, 19 Oct 2002 01:21:20 -0300
From: adm@domain.com
To: check-auth@verifier.port25.com
Subject:
MIME-Version: 1.0
Content-Type: text/plain;
charset=ISO-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 7bit
User-Agent: Internet Messaging Program (IMP) H3 (4.0.1)