// Setup properties
Properties props = new Properties();
props.put("mail.pop3.auth", true);
props.put("mail.pop3.host", "myHost");

// Setup authentication, get session
Authenticator auth = new Authenticator() {
public PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(user, pass);
}
};
Session session = Session.getInstance(props, auth);