type Exception report

message

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

exception

org.apache.jasper.JasperException: Unable to compile class for JSP

No Java compiler was found to compile the generated source for the JSP. 
This can usually be solved by copying manually $JAVA_HOME/lib/tools.jar from the JDK 
to the common/lib directory of the Tomcat server, followed by a Tomcat restart. 
If using an alternate Java compiler, please check its installation and access path.

	org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:127)
	org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:351)
	org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:415)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:458)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:552)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:291)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:856)

note The full stack trace of the root cause is available in the Tomcat logs.

Apache Tomcat/5.0.18
为什么出现这个错误？
我的jdk配置路径是对的！


恳请高手帮忙！！！！！