Forcing MTOM output for faults with CXF in EAP 6

Issue

• CXF is returning SOAP faults with Content-Type of application/soap+xml;charset=UTF-8 and successful submissions with a ContentType of multipart/related;type="application/xop+xml" when we have enabled MTOM. How to force xop+xml Content-Type for all responses?
• Previous web service implementation, Metro, returned MTOM output, or multipart mime, for both success and fault responses while CXF is only using MTOM for non-fault responses.
• Forcing MTOM enabled web service to use MTOM for faults as well as successful operations