You can disable the inclusion of the stack trace in the SOAP fault message by setting the
com.sun.xml.ws.fault.SOAPFaultBuilder.disableCaptureStackTrace
Java startup property tofalse
.
Source: http://docs.oracle.com/middleware/1212/wls/WSGET/jax-ws-soapfaults.htm#BABGDDEA
The chapter Using Unmodeled Faults in the same document has some explanation and a reference to SOAP Message Handlers. This would allow you to tweak processing of unmodeled faults i.e. RuntimeException
s.