SoapUI SOAPClient doesn't pick up HttpClient properties when hosting WSDL locally ("file://...") in SOA-P 5

Issue

• We need a specific SOAPClient action to use our forward proxy. We have set the below properties associated with the SOAP action:

  <action name="soapui-client-action" class="org.jboss.soa.esb.actions.soap.SOAPClient">
    <property name="wsdl" value="file:/opt/jboss-soa-p-5.3.1/jboss-as/server/default/wsdl/SampleWS.wsdl"/>
    <property name="http-client-properties">
      <http-client-property name="http.proxyHost" value="${http.proxyHost}"/>
      <http-client-property name="http.proxyPort" value="${http.proxyPort}"/> 
    </property>
    ...
  </action>

• However these values appear not to be used and the SOAPClient action's connection is timing out.