The value for the useBean class attribute is invalid.

안녕하세요 상기의 제목과 같은 에러때문에 고생 좀 하고 있습니다.   설정상 문제인 것 같은 데요 좀 봐 주시겠어요   참고로 build 폴더에 net.daum.DaumMain.DaumMainDW  클래스는 있습니다.   1. index.jsp <jsp:useBean id="beanTestMain" class="net.daum.DaumMain.DaumMainDW" scope="request" />   2.환경 :  eclipse-jee-juno-SR2-win32+ apache-tomcat-6.0.37   3.로그   심각: Servlet.service() for servlet jsp threw exception org.apache.jasper.JasperException: /index.jsp(18,0) The value for the useBean class attribute net.daum.DaumMain.DaumMainDW is invalid.  at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:40)  at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)  at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:148)  at org.apache.jasper.compiler.Generator$GenerateVisitor.visit(Generator.java:1233)  at org.apache.jasper.compiler.Node$UseBean.accept(Node.java:1178)  at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2361)  at org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2411)  at org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2417)  at org.apache.jasper.compiler.Node$Root.accept(Node.java:495)  at org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2361)  at org.apache.jasper.compiler.Generator.generate(Generator.java:3461)  at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:231)  at org.apache.jasper.compiler.Compiler.compile(Compiler.java:354)  at org.apache.jasper.compiler.Compiler.compile(Compiler.java:334)  at org.apache.jasper.compiler.Compiler.compile(Compiler.java:321)  at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:592)  at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:328)  at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)  at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)  at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)  at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)  at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)  at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)  at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)  at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)  at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)  at org.apache.catalina.core.StandardEngineVal‎ve.invoke(StandardEngineVal‎ve.java:109)  at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)  at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)  at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)  at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)  at java.lang.Thread.run(Thread.java:619)