// 5) disposition-field
mdnReport.append(disposition.toString());
mdnReport.append("\r\n");
MimeBodyPart mdnPart = new MimeBodyPart();
mdnPart.setContent(mdnReport.toString(), "message/disposition-notification");
multiPart.addBodyPart(mdnPart);
// Part 3: The optional third part, the original message is omitted.
// We don't want to propogate over-sized, virus infected or
// other undesirable mail!
// There is the option of adding a Text/RFC822-Headers part, which