public MimeMessage createMimeMessage() {
        if (session == null) {
            createSession();
        }
        return new MimeMessage(session);
    }
Factory method to return a blank JavaMail message. You should use the
object returned and set desired message properties. When done, pass the
object to the addMessage(Message) method.

@return a new JavaMail message.
xmppserver/src/main/java/org/jivesoftware/util/EmailService.java