Failed in adding a new portlet

I tried to add a new portlet into pluto1.1.2, but failed unfortunately.
Referring to the pluto Admin Help page,
1. i created a test.xml in c:/pluto/conf/Catalina/localhost/ which
content : <Context path="test" docBase="c:\pluto\webapps\test"
crossContext="true"></Context>
2. add page element in pluto-portal-driver-config.xml  as the child of
render-config :
 <page name="test" uri="/WEB-INF/themes/pluto-default-theme.jsp">
      <portlet context="/test" name="test"/>
    </page>

Yes, "test" item is displayed when mouse moved over the "Navigation", but
  error occurs when click the "test". Thanks for your help!

type Exception report

message

description The server encountered an internal error () that prevented
it from fulfilling this request.

exception org.apache.jasper.JasperException
	org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:512)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.pluto.driver.PortalDriverServlet.doGet(PortalDriverServlet.java:142)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)




root cause org.apache.jasper.JasperException
	org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:512)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:395)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:966)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspx_meth_c_forEach_2(pluto_002ddefault_002dtheme_jsp.java:746)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspx_meth_c_otherwise_1(pluto_002ddefault_002dtheme_jsp.java:694)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspx_meth_c_choose_1(pluto_002ddefault_002dtheme_jsp.java:562)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspService(pluto_002ddefault_002dtheme_jsp.java:159)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.pluto.driver.PortalDriverServlet.doGet(PortalDriverServlet.java:142)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)




root cause java.lang.NullPointerException
	org.apache.pluto.driver.services.impl.resource.SupportedModesServiceImpl.isPortletModeSupportedByPortlet(SupportedModesServiceImpl.java:107)
	org.apache.pluto.driver.services.impl.resource.SupportedModesServiceImpl.isPortletModeSupported(SupportedModesServiceImpl.java:80)
	org.apache.pluto.driver.config.impl.DriverConfigurationImpl.isPortletModeSupported(DriverConfigurationImpl.java:128)
	org.apache.pluto.driver.tags.PortletModeAnchorTag.isPortletModeAllowed(PortletModeAnchorTag.java:161)
	org.apache.pluto.driver.tags.PortletModeAnchorTag.doStartTag(PortletModeAnchorTag.java:85)
	org.apache.jsp.WEB_002dINF.themes.portlet_002dskin_jsp._jspx_meth_pluto_modeAnchor_0(portlet_002dskin_jsp.java:193)
	org.apache.jsp.WEB_002dINF.themes.portlet_002dskin_jsp._jspx_meth_pluto_portlet_0(portlet_002dskin_jsp.java:118)
	org.apache.jsp.WEB_002dINF.themes.portlet_002dskin_jsp._jspService(portlet_002dskin_jsp.java:76)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:966)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspx_meth_c_forEach_2(pluto_002ddefault_002dtheme_jsp.java:746)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspx_meth_c_otherwise_1(pluto_002ddefault_002dtheme_jsp.java:694)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspx_meth_c_choose_1(pluto_002ddefault_002dtheme_jsp.java:562)
	org.apache.jsp.WEB_002dINF.themes.pluto_002ddefault_002dtheme_jsp._jspService(pluto_002ddefault_002dtheme_jsp.java:159)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	org.apache.pluto.driver.PortalDriverServlet.doGet(PortalDriverServlet.java:142)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

-- 
  Best Regards.
      jacky