You Shouldn't set  creator for struts  in dwr  file , you only need set creator for actions and method that are used by ajax .
sth like this

 <create creator="spring" javascript="testAction">
        <include method="saveItem"/>
        <include method="editItem"/>
         <param name="beanName" value="testAction"/>
</create>

Besides ,dont forget to add your DWRServlet  configuration in your web.xml

<servlet>
        <servlet-name>dwr-invoker</servlet-name>
        <display-name>DWR Servlet</display-name>
        <description>Direct Web Remoter Servlet</description>
        <servlet-class>com.parstelco.bucket.struts.DWRServlet</servlet-class>
        <init-param>
            <param-name>debug</param-name>
            <param-value>true</param-value>
        </init-param>

<init-param>
            <param-name>testDwrXml</param-name>
     <param-value>/WEB-INF/testDwr.xml </param-value>                                                


</init-param>

</servlet>

I've solved my
problem .but please check this URL out.
http://getahead.ltd.uk/dwr/server/struts

it is offical site of DWR, in this site Joe's written
about using of creator="struts"...