February 21, 2008 at 5:55 PM
This type of error comes when the JVM found two versions of the same jar file.
This error occurs when two classloaders have loaded the same class with different signatures.
ie: you have the same class twice in your CLASSPATH, but the classes are different (usually different versions).
Usually, the reason is that you have included a JAR file in your WEB-INF/lib or WAR file, which is already part of the JVM or Servlet Container (such as jsp-api.jar).
I have solved this problem by deleting el-api.jar and el-impl.jar (because there is another version of this jar file in tomcat lin folder)in all the three samples lib folder.
Hope this will sove the problem.