code: final JsMsgMap getOtherUserPropertyMap() {
          if (otherUserPropertyMap == null) {
              List<String> keys = (List<String>) getApi().getField(JsApiAccess.OTHERPROPERTY_NAME);
              List<Object> values = (List<Object>) getApi().getField(JsApiAccess.OTHERPROPERTY_VALUE);
              otherUserPropertyMap = new JsMsgMap(keys, values);
          }
          return otherUserPropertyMap;
      }
docs: Helper method used by the main Message Property methods to obtain the
  non-JMS-valid Property items in the form of a map.
  <p>
  The method has package level visibility as it is used by JsJmsMessageImpl,
  JsSdoMessageimpl and MQJsJmsMessageEncoderImpl.
  
  @return A JsMsgMap containing the Message Property name-value pairs.