import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import javax.mail.*;
import javax.mail.internet.*;
import javax.mail.event.*;
import java.net.*;
import java.util.*;
public class servletmail extends HttpServlet
{
public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException
{
PrintWriter out=response.getWriter();
response.setContentType("text/html");
try
{
Properties props=new Properties();
props.put("mail.transport.protocol", "smtp");
props.put("mail.smtp.host","smtp.gmail.com");
props.put("mail.smtp.port", "25");
props.put("mail.smtp.auth", "true");
Authenticator authenticator = new Authenticator()
    {
    protected PasswordAuthentication getPasswordAuthentication() 
        {
        return new PasswordAuthentication("user", "pass");
    }
};
Session sess=Session.getDefaultInstance(props,authenticator);
Message msg=new MimeMessage(sess);
msg.setFrom(new InternetAddress("[email protected]"));
msg.addRecipient(Message.RecipientType.TO, new InternetAddress("[email protected]"));
msg.setSubject("Hello JavaMail");
msg.setText("Welcome to JavaMail");
Transport.send(msg);
out.println("mail has been sent");
}
catch(Exception e)
{
System.out.println("err"+e);
}
}
}

im working with above im gettin d following error

servletmail.java:22: reference to Authenticator is ambiguous, both class java.ne
t.Authenticator in java.net and class javax.mail.Authenticator in javax.mail mat
ch
Authenticator authenticator = new Authenticator()
^
servletmail.java:22: reference to Authenticator is ambiguous, both class java.ne
t.Authenticator in java.net and class javax.mail.Authenticator in javax.mail mat
ch
Authenticator authenticator = new Authenticator()
                                  ^
2 errors

i have followed the example in

http://java.sun.com/developer/onlineTraining/JavaMail/contents.html

how should i get the output..will the above code...work what are the changes that need to be made..im using thunderbird smtp server