com.sun.tools.javac.Main is not on the classpath.Perhaps JAVA_HOME does not point to the JDK

eclipse + tomcat 出错
安装eclipse + myeclipse在指定tomcat 时正常，但通过eclipse运行tomcat出错，单独运行正常。找不到解决方法，直接安装eclipse的tomcat插件，问题解决。哪位仁兄有碰到类此的问题解决了，望回帖，谢谢。

严重: Javac exception
Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK
 at org.apache.tools.ant.taskdefs.compilers.CompilerAdapterFactory.getCompiler(CompilerAdapterFactory.java:106)
 at org.apache.tools.ant.taskdefs.Javac.compile(Javac.java:935)
 at org.apache.tools.ant.taskdefs.Javac.execute(Javac.java:764)
 at org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:382)
 at org.apache.jasper.compiler.Compiler.compile(Compiler.java:472)
 at org.apache.jasper.compiler.Compiler.compile(Compiler.java:451)
 at org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
 at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:511)
 at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:295)
 at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
 at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
 at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
 at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
 at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
 at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:118)
 at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
 at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
 at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
 at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
 at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
 at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
 at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:683)
 at java.lang.Thread.run(Unknown Source)