I am sending a mail using java mail api.
A few lines of the code are:

String host="ftpmp.pelzer.de";
... other fields defined here...
boolean sessionDebug=true;
Properties props=System.getProperties();
props.put("mail.host",host);
props.put("mail.transport.protocol","smtp");
... other code...
Transport.send(msg);


but it is giving java.net.ConnectException: Connection refused
What might be the possible reasons and there solutions.

Thanks