When defining <wsdl-host>jbossws.undefined.host</wsdl-host> the JBoss CXF indeed replaces the wsoap12:address location within the WSDL with the actual address. But the same substitution is not applied on the WSDL within WS-MEX metadata. Seems like the location is being replaced with an address containing jbossws.undefined.host, instead of the actual host. This causes STS implementations that also expose MEX to fail.