SAP Internet mail

Hi, i want to configure SAP server to send and recieve external emails and i have made all the configuration as given in SAPHelp.Actually i am getting problem while making the connection test of SAPconnect and getting error,

"Error when accessing the external software: Test not possible"

My SAP server is on Windows 2000 server and my email server is on linux machine in Local area network only.

Here, i want to configure SAP to send mails through that email server.

If anybody have any kind of help on the same, it will be appreciated.

Regards,

Vivek Chauhan