Send mail exception

Question

hai guys,
i am getting the following exception when i try to execute my program which i have given below. can u guys sort this out for me
javax.mail.SendFailedException: Sending failed;
nested exception is:
class javax.mail.SendFailedException: Invalid Addresses;
nested exception is:
class javax.mail.SendFailedException: 552 You must authenticate via SMTP
AUTH or you must POP first. See http://SoftHome.net/help/popfirst.html .
program:
import java.util.Properties;
import javax.mail.*;
import javax.mail.internet.*;
import java.io.UnsupportedEncodingException;
public class MailExample {
     public static void main (String args[]) {
          String host = "mail.softhome.net";
          String from = "[email protected]";
          String to = "[email protected]";     
          try {       
               // Get system properties     
               Properties props = System.getProperties();          
               // Setup mail server     
               Authenticator auth = new PopupAuthenticator();     
               props.put("mail.smtp.host", host);          
               // Get session     
               Session session = Session.getInstance(props, auth);     
               //session.setDebug(true);          
               // Define message     
               MimeMessage message = new MimeMessage(session);          
               // Set the from address     
               message.setFrom(new InternetAddress(from,"FromName"));          
               // Set the to address     
               message.addRecipient(Message.RecipientType.TO,new InternetAddress(to,"ToName"));
               // Set the subject     
               message.setSubject("Hello JavaMail");
               // Set the content     
               message.setText("Welcome to JavaMail");          
               // Send message     
               Transport.send(message);     
               System.out.println("OK Man");     
          }     catch (MessagingException e) {e.toString();System.out.println(e);
          }     catch (UnsupportedEncodingException e) {e.toString();System.out.println(e);
          }     catch (Exception e) {e.toString();System.out.println(e);}
          static class PopupAuthenticator extends Authenticator {
               public PasswordAuthentication getPasswordAuthentication() {  
                    return new PasswordAuthentication("UserName", "Password");
                    } }}

Answer 1

try to add auth attribute to properties
eg.
props.put("mail.smtp.auth", "true");