jbpm 错误 loader constraint violation: when resolving interface method "javax.servlet.jsp.JspApplicati

加jbpm 后运行 jsp 报错：  Servlet.service() for servlet jsp threw exceptionjava.lang.LinkageError: loader constraint violation: when resolving interface method "javax.servlet.jsp.JspApplicationContext.getExpressionFactory()Ljavax/el/ExpressionFactory;" the class loader (instance of org/apache/jasper/servlet/JasperLoader) of the currentclass, org/apache/jsp/index_jsp, and the class loader (instance of org/apache/catalina/loader/StandardClassLoader) for resolved class, javax/servlet/jsp/JspApplicationContext, have different Class objects for the type javax/el/ExpressionFactory used in thesignature at org.apache.jsp.index_jsp._jspInit(index_jsp.java:23) at org.apache.jasper.runtime.HttpJspBase.init(HttpJspBase.java:52) at org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:159) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:329) 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:717) 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:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:852) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:619) 

jbpm4 在tomcat6 下面ssh2 这个错误！

原因是项目中WEB-INF/lib中的三个jar包(juel.jar, juel-engine.jar, juel-impl.jar)和

tomcat6下lib中jar包(el-api.jar)冲突

解决方法：

方法一：换成tomcat5.5 一点问题也没有了

方法二：将juel.jar, juel-engine.jar, juel-impl.jar这三个包复制到tomcat6下lib中，

并删除原来的el-api.jar，切记要把WEB-INF/lib中的juel.jar, juel-engine.jar, juel-impl.jar删除。

不然还是要冲突。

http://blog.csdn.net/jiazimo/article/details/5506140