Since JAX-WS allows normal messages and XOP encoded messages for MTOM enabled
service, it should send non-XOP encoded messages to requests coming from
non-MTOM aware clients.
JAX-WS can find about the client is MTOM aware from the HTTP headers in the
request. It should send normal messages if Content-Type header is not
application/xop+xml and ACCEPT header doesn't contain application/xop+xml.