private Packet packet(Message m) {
   final Packet p = new Packet();
   // TODO when do we use xmlCodec?
   p.codec = soapCodec;
   if (m != null) p.setMessage(m);
   MTOMFeature mf = features.get(MTOMFeature.class);
   if (mf != null) {
     p.setMtomFeature(mf);
   }
   return p;
 }