mail send problem using smtp

[sudipmondal440]

import javax.mail.*;
import javax.mail.inte rnet.*;
import java.util.*;
import javax.activatio n.*;
import javax.swing.tex t.*;
import javax.swing.*;
import java.io.*;
import java.awt.*;
import javax.activatio n.DataSource;
import javax.mail.inte rnet.MimeMessag e;

/**
*
* @author rathit
*/
public class SendMail {

/** Creates a new instance of SendMail */
public SendMail() {
}
private class SMTPAuthenticat or extends javax.mail.Auth enticator{
public PasswordAuthent ication getPasswordAuth entication(){
String username = "Muni";
String password = "Raj";
return new PasswordAuthent ication(usernam e, password);
}
}
public void postMail() throws MessagingExcept ion {

boolean debug = false;
String recipients[] = {"java.muni@red iffmail.com"};
String recipientsCC[] = {"likhis_007@ya hoo.com"};

String subject = "Mail";
String message = "This is body for the message";
String from = "pop_muni@yahoo .com";
Properties props = new Properties();
props.put("mail .smtp.host","20 8.220.245.70");//mail.yahoo.com/68.142.225.208
props.put("mail .smtp.auth","tr ue");
Authenticator auth = new SMTPAuthenticat or();
Session session = Session.getDefa ultInstance(pro ps, auth);
session.setDebu g(debug);
MimeMessage msg = new MimeMessage(ses sion);
// set the from and to address
InternetAddress addressFrom = new InternetAddress (from);
msg.setFrom(add ressFrom);
InternetAddress[] addressTo = new InternetAddress[recipients.leng th];
for(int i = 0; i < recipients.leng th; i++){
addressTo[i] = new InternetAddress (recipients[i]);
}
msg.setRecipien ts(Message.Reci pientType.TO, addressTo);

//recipientsCC[]
InternetAddress[] addressCC = new InternetAddress[recipientsCC.le ngth];
for(int j = 0; j < recipientsCC.le ngth; j++){
addressCC[j] = new InternetAddress (recipientsCC[j]);
}
msg.setRecipien ts(Message.Reci pientType.CC, addressCC);

// Optional : You can also set your custom headers in the Email if you Want
msg.addHeader(" MyHeaderName", "myHeaderValue" );
msg.setSubject( subject);
msg.setContent( message,"text/html");
Transport.send( msg);
System.out.prin tln("Mail Successfully Sent");

}//End of postMail()
/**
* @param args the command line arguments
*/
public static void main(String[] args) throws MessagingExcept ion {
// TODO code application logic here
new SendMail().post Mail();
}

}


when run
Exception in thread "main" java.lang.NoCla ssDefFoundError : javax/activation/DataSource
at test.SendMail.p ostMail(SendMai l.java:53)
at test.SendMail.m ain(SendMail.ja va:83)
Java Result: 1

pls help me