Problem sending mail with authentication

Question

Please help as I've spent the last two days trying various things to solve my problem to no avail. I have been able to send email through the smtp server I have access to (just for interest, smtp.cs.stir.ac.uk), to email addresses in the same domain (e.g [email protected]) because the server does not require me to log in to do this - I can do it anonymously.
My problem comes when I try to send an email outwith the cs.stir.ac.uk subdomain, (e.g [email protected]) because it requires me to login. So I set about learning about authenticating with smtp servers using the javamail package, and I found two methods of doing it, both of which threw a javax.mail.AuthenticationFailedException. I believe this exception is only thrown when a username or password is wrong and I can't understand it because I'm definitely using the same user/pass combo as I do to log into my webmail. The stack trace for the exception is:
javax.mail.Service.connect(Service.java:264)
javax.mail.Service.connect(Service.java:134)
javax.mail.Service.connect(Service.java:86)
com.sun.mail.smtp.SMTPTransport.connect(SMTPTransport.java:144)
javax.mail.Transport.send0(Transport.java:150)
javax.mail.Transport.send(Transport.java:80)
EmailAuth.send(EmailAuth.java:80)
EmailAuth.<init>(EmailAuth.java:40)
EmailPanel.actionPerformed(EmailPanel.java:56)
javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1764)
javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1817)
javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:419)
javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:257)
javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:245)
java.awt.Component.processMouseEvent(Component.java:5093)
java.awt.Component.processEvent(Component.java:4890)
java.awt.Container.processEvent(Container.java:1566)
java.awt.Component.dispatchEventImpl(Component.java:3598)
java.awt.Container.dispatchEventImpl(Container.java:1623)
java.awt.Component.dispatchEvent(Component.java:3439)
java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3450)
java.awt.LightweightDispatcher.processMouseEvent(Container.java:3165)
java.awt.LightweightDispatcher.dispatchEvent(Container.java:3095)
java.awt.Container.dispatchEventImpl(Container.java:1609)
java.awt.Window.dispatchEventImpl(Window.java:1585)
java.awt.Component.dispatchEvent(Component.java:3439)
java.awt.EventQueue.dispatchEvent(EventQueue.java:450)
java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:197)
java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:144)
java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:136)
java.awt.EventDispatchThread.run(EventDispatchThread.java:99)
And the code I'm using is:
import javax.mail.*;
import javax.mail.internet.*;
import java.util.*;
import java.io.*;
public class EmailAuth
     public String uname;
     public String pword;
  public EmailAuth(String host, String username, String password, String message,
            String subject, String from, String[] to) throws MessagingException {
            uname = username;
            pword = password;
            send(host, username, password, message, subject, from, to);
  public void send( String host, String username, String password, String message,
            String subject, String from, String[] to) throws MessagingException
    boolean debug = false;
     Properties props = new Properties();
     props.put("mail.smtp.host", host);
     props.put("mail.smtp.auth", "true");
    Authenticator auth = new SMTPAuthenticator();
    Session session = Session.getDefaultInstance(props, auth);
    session.setDebug(debug);
     // create a message
    Message msg = new MimeMessage(session);
    // set the from and to address
    InternetAddress addressFrom = new InternetAddress(from);
    msg.setFrom(addressFrom);
    InternetAddress[] addressTo = new InternetAddress[to.length];
    for (int i = 0; i < to.length; i++)
        addressTo[i] = new InternetAddress(to);
msg.setRecipients(Message.RecipientType.TO, addressTo);
// Setting the Subject and Content Type
msg.setSubject(subject);
msg.setContent(message, "text/plain");
Transport.send(msg);
private class SMTPAuthenticator extends javax.mail.Authenticator
public PasswordAuthentication getPasswordAuthentication(String username, String password)
return new PasswordAuthentication(username, password);
Any help is greatly appreciated!!

Answer 1

try logging in to the SMTP server with that username/pwd manually. i've done this in win32 using telnet...
at the command prompt, enter "telnet mail.host.com 143", then from within telnet type "a1 login username password". the SMTP server should respond with something like "a1 OK LOGIN completed" if accepted. then, close the session by entering "a2 logout" (or just kill the telnet session).
the exchange should look like this:
telnet mail.host.com 143 * OK IMAP4rev1 server ready (3.0.14)
a1 login username password
a1 OK LOGIN completed
a2 logout
* BYE IMAP4rev1 Server logging out
a2 OK LOGOUT completed
Connection to host lost.
peace
bobD