JBoss ESB custom SOAPProxy action publishes only "<definitions/>" as WSDL

Issue

• I have a custom soap proxy action which extends org.jboss.soa.esb.actions.soap.proxy.SOAPProxy:

package com.example.esb.actions;

import ...

public class CustomSOAPProxy extends SOAPProxy {

• I defined an ESB service using this soap proxy like as below, but the published WSDL only shows "<definitions/>."

  <service category="samples" name="MyService" description="..." invmScope="GLOBAL">
    <listeners>
      <http-gateway name="Http-Gateway" />
    </listeners>
    <actions mep="RequestResponse">
      <action name="soap-proxy" class="com.example.esb.actions.CustomSOAPProxy">
        ...
      </action>
    </actions>
  </service>