You need richfaces-3.0.1-SNAPSHOT.jar in WEB-INF/lib and you have to change in jboss-4.0.5.GA/server/default/deploy/jbossweb-tomcat55.sar/META-INF/jboss-service.xml from false to true | <attribute name="Java2ClassLoadingCompliance">true</attribute> | <!-- A flag indicating if the JBoss Loader should be used. This loader | uses a unified class loader as the class loader rather than the tomcat | specific class loader. | The default is false to ensure that wars have isolated class loading | for duplicate jars and jsp files. | --> | <attribute name="UseJBossWebLoader">true</attribute> | <!-- The list of package names that should not be loaded without | delegating to the parent class loader before trying the web app | class loader. The packages listed here are those tha are used by | the web container implementation and cannot be overriden. | This only applies when UseJBossWebLoader=false. | --> | for jboss4.2.0 is the same just jboss-service.xml has a different path. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4060792#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...