In 4.0.4, JspFactory appears in server/xxx/lib/javax.servlet.jsp.jar. In 4.2.2 it appears in server/xxx/lib/jsp-api.jar. The one in jsp-api.jar contains the getJspApplicationContext method. Your application must be picking up a copy of that class from some other location. One way to track this down is to restart the app server using the "-verbose:class" JVM command line option. This option identifies the jar file for every class loaded. Start the app server and once it is up deploy your app. The jar file for JspFactory should show up on the command line. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4165424#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...