Tomcat needs the jasper-compiler-jdt.jar file to compile jsp files. But my deployed application also needs the jasper-compiler-jdt.jar but in a different version than the one used by Tomcat 5.5. So how do I make this work. Only one version of the jasper-compiler-jdt must be in the /server/default/lib folder of JBoss. So either my application throws an exception or it's Tomcat depending on the jar version. Is there a way to tell Tomcat to use its own jasper-compiler-jdt.jar within JBoss?