Enviar E-mail pelo JAVA

Olá,

Possuo esse codigo que envia e-mail pelo java..... Mas quando tento executar ele ele dá o seguinte erro.

package Mail;
import java.io.*;
import javax.mail.*;
import javax.mail.internet.*;
import java.util.*;

public class Spammer {
   
    public static void postMail(String mensagem, String para, String assunto,String propriedade1, String propriedade2, String de) throws MessagingException {
        final boolean debug = false;
        
        //Set the host smtp address
        Properties props = new Properties();
        props.put(propriedade1, propriedade2);
        
        // create some properties and get the default Session
        Session session = Session.getInstance(props, null);
        Message msg = new MimeMessage(session);
        try {
            // "de" e "para"!!
            msg.setFrom(new InternetAddress(de));
            msg.setRecipient(Message.RecipientType.TO, new InternetAddress(para));
            
            // nao esqueca da data!
            // ou ira 31/12/1969 !!!
            msg.setSentDate(new Date());
            
            msg.setSubject(assunto);
            
            msg.setText(mensagem);
            
            // evniando mensagem (tentando)
            Transport.send(msg);
        } catch (AddressException e) {
         
        } catch (MessagingException e) {
                   }

    }
}

Erro

java.lang.NoClassDefFoundError: javax/activation/DataSource

at Mail.Spammer.postMail(Spammer.java:33)

at grafica.index.user(index.java:2028)

at grafica.index.jButton1ActionPerformed(index.java:1975)

at grafica.index.access$1900(index.java:33)

at grafica.index$20.actionPerformed(index.java:1466)

at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1786)

at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1839)

at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)

at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258)

at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:245)

at java.awt.Component.processMouseEvent(Component.java:5100)

at java.awt.Component.processEvent(Component.java:4897)

at java.awt.Container.processEvent(Container.java:1569)

at java.awt.Component.dispatchEventImpl(Component.java:3615)

at java.awt.Container.dispatchEventImpl(Container.java:1627)

at java.awt.Component.dispatchEvent(Component.java:3477)

at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3483)

at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3198)

at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3128)

at java.awt.Container.dispatchEventImpl(Container.java:1613)

at java.awt.Window.dispatchEventImpl(Window.java:1606)

at java.awt.Component.dispatchEvent(Component.java:3477)

at java.awt.EventQueue.dispatchEvent(EventQueue.java:480)

at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:201)

at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:145)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:137)

at java.awt.EventDispatchThread.run(EventDispatchThread.java:100)

Não sei o que pode ser feito mais..... Espero que alguem possa me ajudar.

Att
Kiko