SMTP not accepting my outgoing mail

[Selvi]

I am having RH7.1 in my office with Dialup connectivity also running Squid over that. In another PC (WIN2000) configured Outlook express as a mail client. I   The problem is i can send  mail to @anysite.com  by connecting telnet to above said linux PC.   In Outlook express i have configured SMTP is RH7.1 ipaddres.now when i send any mail through outlook express the SMTP server is not connecting.   The error returns like this in OExpress   "The connection to the server has failed. Account: 'Bala', Server: '130.202.11.253', Protocol: SMTP, Port: 25, Secure(SSL): No, Socket Error: 10061, Error Number: 0x800CCC0E     Can any one help me ?