When wsa:action is not set explicitly the builder just appends IN or OUT to the endpoint's QName. This does not indicate as to what operation was perfomed when we peek the SOAP Message header.

All along I was thinking that it worked fine for JAXWS tests, but it
has been hard-coded in JAXWSMetaDataBuilder.java:

// default action values

{ // TODO: figure out a way to assign message name instead of IN and OUT String tns = epMetaData.getPortName().getNamespaceURI(); String portTypeName = epMetaData.getPortName().getLocalPart(); addrExt.setInboundAction(tns + "/" + portTypeName + "/IN"); if (!opMetaData.isOneWay()) addrExt.setOutboundAction(tns + "/" + portTypeName + "/OUT"); }