Tomcat6 Startup error Exception starting filter struts Com.opensymphony.xwork2.spring.SpringObjectFactory.getClassInstance

2010-7-27 11:16:43 Org.apache.catalina.core.StandardContext Filterstart
Serious: Exception starting filter Struts
Java.lang.NullPointerException
At Com.opensymphony.xwork2.spring.SpringObjectFactory.getClassInstance

(springobjectfactory.java:188)
At

Com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.verifyResultType

(xmlconfigurationprovider.java:479)
At Com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addResultTypes

(xmlconfigurationprovider.java:450)
At Com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.addPackage

(xmlconfigurationprovider.java:407)
At Com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadPackages

(xmlconfigurationprovider.java:239)
At Org.apache.struts2.config.StrutsXmlConfigurationProvider.loadPackages

(strutsxmlconfigurationprovider.java:111)
At Com.opensymphony.xwork2.config.impl.DefaultConfiguration.reload

(defaultconfiguration.java:152)
At Com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration

(configurationmanager.java:52)
At Org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration

(dispatcher.java:395)
At Org.apache.struts2.dispatcher.Dispatcher.init (dispatcher.java:452)
At Org.apache.struts2.dispatcher.FilterDispatcher.init (filterdispatcher.java:201)
At Org.apache.catalina.core.ApplicationFilterConfig.getFilter

(applicationfilterconfig.java:275)
At Org.apache.catalina.core.ApplicationFilterConfig.setFilterDef

(applicationfilterconfig.java:397)
At org.apache.catalina.core.applicationfilterconfig.<init>

(applicationfilterconfig.java:108)
 at Org.apache.catalina.core.StandardContext.filterStart ( standardcontext.java:3696)
 at Org.apache.catalina.core.StandardContext.start (standardcontext.java:4343 )
 at org.apache.catalina.core.ContainerBase.addChildInternal (containerbase.java:791)
 at Org.apache.catalina.core.ContainerBase.addChild (containerbase.java:771)
 at Org.apache.catalina.core.StandardHost.addChild (standardhost.java:525)
 at Org.apache.catalina.startup.HostConfig.deployDirectory (hostconfig.java:920)
 at Org.apache.catalina.startup.HostConfig.deployDirectories (hostconfig.java:883)
 at Org.apache.catalina.startup.HostConfig.deployApps (hostconfig.java:492)
 at Org.apache.catalina.startup.HostConfig.start (hostconfig.java:1138)
 at Org.apache.catalina.startup.HostConfig.lifecycleEvent (hostconfig.java:311)
 at Org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent

(lifecyclesupport.java:117)
 at Org.apache.catalina.core.ContainerBase.start (containerbase.java:1053 )
 at Org.apache.catalina.core.StandardHost.start (standardhost.java:719)
 at Org.apache.catalina.core.ContainerBase.start (containerbase.java:1045)
 at Org.apache.catalina.core.StandardEngine.start (standardengine.java:443)
 at Org.apache.catalina.core.StandardService.start (standardservice.java:516)
 at Org.apache.catalina.core.StandardServer.start (standardserver.java:710)
 at Org.apache.catalina.startup.Catalina.start (catalina.java:566)
 at Sun.reflect.NativeMethodAccessorImpl.invoke0 (Native method)
 at Sun.reflect.NativeMethodAccessorImpl.invoke (nativemethodaccessorimpl.java:39)
 at Sun.reflect.DelegatingMethodAccessorImpl.invoke

(delegatingmethodaccessorimpl.java:25)
At Java.lang.reflect.Method.invoke (method.java:597)
At Org.apache.catalina.startup.Bootstrap.start (bootstrap.java:288)
At Org.apache.catalina.startup.Bootstrap.main (bootstrap.java:413)
2010-7-27 11:16:43 org.apache.catalina.core.StandardContext Start
Serious: Error Filterstart
2010-7-27 11:16:43 org.apache.catalina.core.StandardContext Start
Serious: Context [/csmartshop] startup failed due to previous errors

My struts2.
The packages are as follows:
Commons-logging-1.0.4.jar

Freemarker-2.3.8.jar

Ognl-2.6.11.jar

Struts2-core-2.0.11.jar

Xwork-2.0.4.jar

The above error occurred
The reason is to add a more package, remove this package can be
Struts2-spring-plugin-2.0.11.jar