Need help regarding E-mail..!!

I am trying to write a code for sending a mail in JAVA..
And I am getting the error
(Toggle Plain Text)

javax.mail.MessagingException: Could not connect to SMTP host: mail.yahoo.com, port: 25;


What can my mistake possibly be..??
Please help me find my mistake..

My code is :
[code]

package learn;
import java.util.*;
import java.io.*;
import javax.mail.*;
import javax.mail.internet.*;
import javax.activation.*;

public class maal {

public static void main(String[] args) {

// SUBSTITUTE YOUR EMAIL ADDRESSES HERE!!!
String to = "shveetis@gmail.com";
String from = "shveetis@yahoo.co.in";
// SUBSTITUTE YOUR ISP'S MAIL SERVER HERE!!!
String host = "203.187.209.1";

// Create properties for the Session
Properties props = new Properties();

// If using static Transport.send(),
// need to specify the mail server here
props.put("mail.smtp.host", host);
// To see what is going on behind the scene
// props.put("mail.debug", "true");

// Get a session
Session session = Session.getInstance(props);

try {
// Get a Transport object to send e-mail
Transport bus = session.getTransport("smtp");

// Connect only once here
// Transport.send() disconnects after each send
// Usually, no username and password is required for SMTP
//bus.connect();
bus.connect("mail.yahoo.com", "srathi1", "775916");

// Instantiate a message
Message msg = new MimeMessage(session);

// Set message attributes
msg.setFrom(new InternetAddress(from));
InternetAddress[] address = {new InternetAddress(to)};
msg.setRecipients(Message.RecipientType.TO, address);
// Parse a comma-separated list of email addresses. Be strict.
msg.setRecipients(Message.RecipientType.CC,
InternetAddress.parse(to, true));
// Parse comma/space-separated list. Cut some slack.
msg.setRecipients(Message.RecipientType.BCC,
InternetAddress.parse(to, false));

msg.setSubject("Test E-Mail through Java");
msg.setSentDate(new Date());

// Set message content and send
setTextContent(msg);
msg.saveChanges();
bus.sendMessage(msg, address);

setMultipartContent(msg);
msg.saveChanges();
bus.sendMessage(msg, address);

setFileAsAttachment(msg, "C:/WINDOWS/CLOUD.GIF");
msg.saveChanges();
bus.sendMessage(msg, address);

setHTMLContent(msg);
msg.saveChanges();
bus.sendMessage(msg, address);

bus.close();

}
catch (MessagingException mex) {
// Prints all nested (chained) exceptions as well
mex.printStackTrace();
// How to access nested exceptions
while (mex.getNextException() != null) {
// Get next exception in chain
Exception ex = mex.getNextException();
ex.printStackTrace();
if (!(ex instanceof MessagingException)) break;
else mex = (MessagingException)ex;
}
}
}

public static void setTextContent(Message msg) throws MessagingException {
// Set message content
String mytxt = "This is a test of sending a " +
"plain text e-mail through Java.\n" +
"Here is line 2.";
msg.setText(mytxt);

// Alternate form
msg.setContent(mytxt, "text/plain");

}

public static void setMultipartContent(Message msg) throws MessagingException {
// Create and fill first part
MimeBodyPart p1 = new MimeBodyPart();
p1.setText("This is part one of a test multipart e-mail.");

// Create and fill second part
MimeBodyPart p2 = new MimeBodyPart();
// Here is how to set a charset on textual content
p2.setText("This is the second part", "us-ascii");

// Create the Multipart. Add BodyParts to it.
Multipart mp = new MimeMultipart();
mp.addBodyPart(p1);
mp.addBodyPart(p2);

// Set Multipart as the message's content
msg.setContent(mp);
}

public static void setFileAsAttachment(Message msg, String filename)
throws MessagingException {

// Create and fill first part
MimeBodyPart p1 = new MimeBodyPart();
p1.setText("This is part one of a test multipart e-mail." +
"The second part is file as an attachment");

// Create second part
MimeBodyPart p2 = new MimeBodyPart();

// Put a file in the second part
FileDataSource fds = new FileDataSource(filename);
p2.setDataHandler(new DataHandler(fds));
p2.setFileName(fds.getName());

// Create the Multipart. Add BodyParts to it.
Multipart mp = new MimeMultipart();
mp.addBodyPart(p1);
mp.addBodyPart(p2);

// Set Multipart as the message's content
msg.setContent(mp);
}

public static void setHTMLContent(Message msg) throws MessagingException {

String html = "<html><head><title>" +
msg.getSubject() +
"</title></head><body><h1>" +
msg.getSubject() +
"</h1><p>This is a test of sending an HTML e-mail" +
" through Java.</body></html>";

// HTMLDataSource is an inner class
msg.setDataHandler(new DataHandler(new HTMLDataSource(html)));
}

static class HTMLDataSource implements DataSource {
private String html;

public HTMLDataSource(String htmlString) {
html = htmlString;
}

// Return html string in an InputStream.
// A new stream must be returned each time.
public InputStream getInputStream() throws IOException {
if (html == null) throw new IOException("Null HTML");
return new ByteArrayInputStream(html.getBytes());
}

public OutputStream getOutputStream() throws IOException {
throw new IOException("This DataHandler cannot write HTML");
}

public String getContentType() {
return "text/html";
}

public String getName() {
return "JAF text/html dataSource to send e-mail only";
}
}
}

[/code]