Error trying to send email -- IOException while sending message

Question

Email is successful when:
I run my application through JDeveloper
or
when I use a classpath, but if I try to execute app via a jar file, i get the following error message: IOException while sending message.
The jar file does include mail.jar and activation.jar.
Below is my email code:
import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;
public class JMAR_Mail {
private String sendTo;
private String sentFrom;
private String host;
private String messageSubject;
private String messageText;
private MimeMessage msg;
public JMAR_Mail() {}
public JMAR_Mail(String sendTo, String sentFrom, String _host) {
sendTo = _sendTo;
sentFrom = _sentFrom;
host = _host;
public void setEmailSubject(String _messageSubject) {
messageSubject = _messageSubject;
} // end setEmailSubject
public void setEmailText(String _text) {
messageText = _text;
public void sendEmail() throws MessagingException {   
// create some properties and get the default Session
Properties props = System.getProperties();
props.put("mail.smtp.host", host);
Session session = Session.getInstance(props, null);
InternetAddress addr = new InternetAddress();
// parses comma separted list of email addresses
InternetAddress[] address = addr.parse(sendTo);
msg = new MimeMessage(session);
msg.setFrom(new InternetAddress(sentFrom));
msg.setSubject(messageSubject);
msg.setText(messageText);
msg.setRecipients(Message.RecipientType.TO, address);
msg.setSentDate(new Date());
Transport.send(msg);
} // end sendEmail
}

Answer 1

You don't want to include those jar files in your jar file,
you want to reference them:
http://forum.java.sun.com/thread.jspa?forumID=43&threadID=762763