multipart.setParent(message);
BodyPart p1 = new BodyPart();
Header h1 = new Header();
h1.addField(Fields.contentType("text/plain"));
p1.setHeader(h1);
p1.setBody(new StringBody("this stuff"));
BodyPart p2 = new BodyPart();
Header h2 = new Header();
h2.addField(Fields.contentType("text/plain"));
p2.setHeader(h2);
p2.setBody(new StringBody("that stuff"));
BodyPart p3 = new BodyPart();
Header h3 = new Header();
h3.addField(Fields.contentType("text/plain"));
p3.setHeader(h3);
p3.setBody(new StringBody("all kind of stuff"));
multipart.addBodyPart(p1);
multipart.addBodyPart(p2);
multipart.addBodyPart(p3);