How do I set HTTP headers from SOAPClient in ESB?

Issue

• How do I set custom HTTPS header parameters like userToken, for example?

POST / HTTP/1.1\r
accept: application/xml\r
accept-encoding: gzip\r
transfer-encoding: identity\r
api-version: 3.2\r
accessmode: conso\r
--->userToken: anonymous\r
connection: close\r
content-Length: \r\n\r\n

Here's my jboss-esb.xml

<action name="soapui-client-action" class="org.jboss.soa.esb.actions.soap.SOAPClient">
  <property name="wsdl" value="http://test:80/MyTest/Test_01?wsdl"/>
  <property name="SOAPAction" value="getMyValue"/>
  <property name="responseAsOgnlMap" value="true" />
<action/>

Within my request Action class, I’m not able to use httpRequest.getHeaders(), because the HttpHeaders list is empty (null).