dwr的A request has been denied as a potential CSRF attack.错误

<servlet>
 <servlet-name>dwr-invoker</servlet-name>
  <servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
  <init-param>
   <param-name>debug</param-name>
   <param-value>true</param-value>
  </init-param>
  <!-- 新加corssDomainSessionSecurity参数 -->
  <init-param>
            <param-name>crossDomainSessionSecurity</param-name>
            <param-value>false</param-value>
    </init-param>
 </servlet>