Prior to testing my application I built and deployed the seam booking example. My running/deployed application under JBoss 4.0.4 GA uses 1) a base abstract class 2) a common class that extends from base class 3) multiple different classes that extend from common class each containing unqiue additional attributes for that class. The following is an attempt at specifing that heirarchy. Abstract Class @Entity @Name("id") @Table(name = "pro_id") @Inheritance(strategy = InheritanceType.JOINED) public abstract class ProId implements Serializable { Common Class @Entity @Name("device") @Table(name = "device") @Inheritance(strategy = InheritanceType.JOINED) public abstract class Deviceextends ProId implements Serializable { Multiple Classes (Devices) with unique attributes @Entity @Name("deviceabc") @Table(name = "device_abc") public class DeviceAbc extends Device implements Serializable { @Entity @Name("devicedef") @Table(name = "device_def") public class DeviceDef extends Device implements Serializable { When I attempt to deploy I get the following exception 2007-04-01 10:45:58,750 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[localhost].[/BiuCmsCommunication]] Exception sending context initialized event to listener instance of class org.jboss.seam.servlet.SeamListener java.lang.IllegalStateException: Two components with the same name and precedence: device at org.jboss.seam.init.Initialization.addComponentDescriptor(Initialization.java:347) at org.jboss.seam.init.Initialization.installRole(Initialization.java:519) at org.jboss.seam.init.Initialization.installScannedComponentAndRoles(Initialization.java:511) at org.jboss.seam.init.Initialization.installScannedClass(Initialization.java:446) at org.jboss.seam.init.Initialization.scanForComponents(Initialization.java:440) at org.jboss.seam.init.Initialization.init(Initialization.java:422) at org.jboss.seam.servlet.SeamListener.contextInitialized(SeamListener.java:33) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3763) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4211) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:759) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:739) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:524) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.apache.commons.modeler.BaseModelMBean.invoke(BaseModelMBean.java:503) at org.jboss.mx.server.RawDynamicInvoker.invoke(RawDynamicInvoker.java:164) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659) at org.apache.catalina.core.StandardContext.init(StandardContext.java:5052) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.apache.commons.modeler.BaseModelMBean.invoke(BaseModelMBean.java:503) at org.jboss.mx.server.RawDynamicInvoker.invoke(RawDynamicInvoker.java:164) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659) at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeployInternal(TomcatDeployer.java:297) at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeploy(TomcatDeployer.java:103) at org.jboss.web.AbstractWebDeployer.start(AbstractWebDeployer.java:371) at org.jboss.web.WebModule.startModule(WebModule.java:83) at org.jboss.web.WebModule.startService(WebModule.java:61) at org.jboss.system.ServiceMBeanSupport.jbossInternalStart(ServiceMBeanSupport.java:289) at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:245) at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155) at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94) at org.jboss.mx.server.Invocation.invoke(Invocation.java:86) at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659) at org.jboss.system.ServiceController$ServiceProxy.invoke(ServiceController.java:978) at $Proxy0.start(Unknown Source) I use the names DeviceAbc and Device in different xhtml in my client. Can anyone explain what this error means? I found another posting for a similiar error, but that did not help. Thanks View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4033536#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...