I looked some more and the missing class is defined in el-ri.jar . But I thought that that jar should no longer be used in JBoss 4.2.1. This means that some Seam class is compiled to look for the com.sun.el.ExpressionFactoryImpl class. Is there a work-around for this? Everything else is working. On my UI elements, I can put security restrictions on them. It's only throwing this when I invoke a method which is @Restricted. Thanks View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4068603#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...