EJB3+JSF+JBoss5.0出现同一个对象转型异常?????????

[Phoenix Slade]

EJB3+JSF+JBoss5.0出现转型异常:
public AddNewsBean() {
try {
InitialContext ctx = new InitialContext();
CategoryLocal local = (CategoryLocal) ctx
.lookup("CategoryBean/local");
ArrayList<Category> category = local.getCategoryList();
categoryList = new ArrayList<SelectItem>();
for (int i = 0; i < category.size(); i++) {
this.categoryList.add(new SelectItem(category.get(i).getId(),
category.get(i).getName()));
}
} catch (Exception e) {
e.printStackTrace();
}
}
异常代码如下:
this.categoryList.add(new SelectItem(category.get(i).getId(),category.get(i).getName()));

异常如下:
17:36:24,757 ERROR [STDERR] java.lang.ClassCastException: com.news.entitybean.Category cannot be cast to com.news.entitybean.Category17:36:24,758 ERROR [STDERR] at com.news.AddNewsBean.<init>(AddNewsBean.java:31)
17:36:24,758 ERROR [STDERR] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
17:36:24,759 ERROR [STDERR] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
17:36:24,759 ERROR [STDERR] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
17:36:24,759 ERROR [STDERR] at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
17:36:24,775 ERROR [STDERR] at java.lang.Class.newInstance0(Class.java:355)
17:36:24,775 ERROR [STDERR] at java.lang.Class.newInstance(Class.java:308)
17:36:24,775 ERROR [STDERR] at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:186)
17:36:24,775 ERROR [STDERR] at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:106)
17:36:24,775 ERROR [STDERR] at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:368)
17:36:24,775 ERROR [STDERR] at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:230)
17:36:24,776 ERROR [STDERR] at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:86)
17:36:24,776 ERROR [STDERR] at javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)
17:36:24,776 ERROR [STDERR] at com.sun.faces.el.FacesCompositeELResolver.getValue(FacesCompositeELResolver.java:72)
17:36:24,776 ERROR [STDERR] at org.apache.el.parser.AstIdentifier.getValue(AstIdentifier.java:61)
17:36:24,776 ERROR [STDERR] at org.apache.el.parser.AstValue.getValue(AstValue.java:107)
17:36:24,776 ERROR [STDERR] at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
17:36:24,776 ERROR [STDERR] at org.apache.jasper.el.JspValueExpression.getValue(JspValueExpression.java:101)
17:36:24,776 ERROR [STDERR] at javax.faces.component.UIOutput.getValue(UIOutput.java:184)
17:36:24,776 ERROR [STDERR] at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:201)
17:36:24,776 ERROR [STDERR] at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:284)
17:36:24,777 ERROR [STDERR] at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:154)
17:36:24,777 ERROR [STDERR] at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:861)
17:36:24,777 ERROR [STDERR] at javax.faces.component.UIComponent.encodeAll(UIComponent.java:937)
17:36:24,777 ERROR [STDERR] at javax.faces.render.Renderer.encodeChildren(Renderer.java:148)
17:36:24,777 ERROR [STDERR] at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:837)
17:36:24,777 ERROR [STDERR] at javax.faces.component.UIComponent.encodeAll(UIComponent.java:930)
17:36:24,777 ERROR [STDERR] at javax.faces.component.UIComponent.encodeAll(UIComponent.java:933)
17:36:24,777 ERROR [STDERR] at com.sun.faces.application.ViewHandlerImpl.doRenderView(ViewHandlerImpl.java:266)
17:36:24,777 ERROR [STDERR] at com.sun.faces.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:197)
17:36:24,777 ERROR [STDERR] at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:110)
17:36:24,777 ERROR [STDERR] at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100)
17:36:24,778 ERROR [STDERR] at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
17:36:24,778 ERROR [STDERR] at javax.faces.webapp.FacesServlet.service(FacesServlet.java:266)
17:36:24,778 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
17:36:24,778 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
17:36:24,778 ERROR [STDERR] at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
17:36:24,778 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
17:36:24,778 ERROR [STDERR] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
17:36:24,778 ERROR [STDERR] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:235)
17:36:24,778 ERROR [STDERR] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
17:36:24,778 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:190)
17:36:24,778 ERROR [STDERR] at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:92)
17:36:24,778 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.process(SecurityContextEstablishmentValve.java:126)
17:36:24,779 ERROR [STDERR] at org.jboss.web.tomcat.security.SecurityContextEstablishmentValve.invoke(SecurityContextEstablishmentValve.java:70)
17:36:24,779 ERROR [STDERR] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
17:36:24,779 ERROR [STDERR] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
17:36:24,779 ERROR [STDERR] at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:158)
17:36:24,779 ERROR [STDERR] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
17:36:24,779 ERROR [STDERR] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:330)
17:36:24,779 ERROR [STDERR] at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:829)
17:36:24,779 ERROR [STDERR] at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:601)
17:36:24,779 ERROR [STDERR] at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
17:36:24,780 ERROR [STDERR] at java.lang.Thread.run(Thread.java:619)

用的包是jsf官网上下的包 或用jboss-5.0.1.GA\server\default\deploy\jbossweb.sar\jsf-libs包都报这个错误
其中用jboss自带的包是因为jboss启动报com.sun....转型异常
大家速度帮解决啊....