I am trying to create a simple web app built with Maven. Maven by default will package all dependencies in the WAR, which causes classloader issues if those libraries are also already in JBoss. Ok, so I thought classloader isolation solved this problem, but apparently I'm not understanding it correctly. The error is that ELResolver was already loaded (the el-api JAR is in my WAR under /WEB-INF/lib): | Caused by: java.lang.ClassNotFoundException: Unexpected error during load of: javax.el.ELResolver, msg=loader constraint violation: loader (instance of org/jboss/mx/loading/UnifiedClassLoader3) previously initiated loading for a | different type with name "javax/el/ELResolver" | at org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:560) | at org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:415) | at java.lang.ClassLoader.loadClass(ClassLoader.java:251) | at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) | Here's my jboss-web.xml. My understanding was that this means I get an isolated classloader that will use the classes in my WAR only and not those of the app server: | <?xml version="1.0" encoding="UTF-8"?> | <!DOCTYPE jboss-web PUBLIC "-//JBoss//DTD Web Application 2.4//EN" | "http://www.jboss.org/j2ee/dtd/jboss-web_4_0.dtd"> | <jboss-web> | <class-loading> | <loader-repository>seam.jboss.org:loader=pjm-mule.war | <loader-repository-config>java2ParentDelegation=false</loader-repository-config> | </loader-repository> | </class-loading> | </jboss-web> | What am I doing wrong? Am I absolutely forced to remove this JAR from my WAR? I have a similar problem with an EAR but this is a much simpler example. Thanks in advance for the help. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4179135#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...