code: public void addAttachment(final DataHandler handler, final String filename)
  		throws MessagingException
  	{
  		final BodyPart part = new MimeBodyPart();
  		part.setFileName(filename);
  		part.setDataHandler(handler);
  		addAttachment(part);
  	}
docs: Adds the attachment.
  
  @param handler
  The DataHandler for the attachment.
  @param filename
  The new Filename for the attachment.
  
  @throws MessagingException
  is thrown if the underlying implementation does not support modification of
  existing values