jboss+mySQL+ CMP+ 主键自动生成

error:ejb/Customerjava.rmi.ServerException: RemoteException occurred in server thread; nested exception is: 
java.rmi.ServerException: EJBException:; nested exception is: 
javax.ejb.EJBException: getGeneratedKeys returned an empty ResultSet
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:325)
at sun.rmi.transport.Transport$1.run(Transport.java:153)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
at java.lang.Thread.run(Thread.java:595)
at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(Unknown Source)
at sun.rmi.transport.StreamRemoteCall.executeCall(Unknown Source)
at sun.rmi.server.UnicastRef.invoke(Unknown Source)
at org.jboss.invocation.jrmp.server.JRMPInvoker_Stub.invoke(Unknown Source)
at org.jboss.invocation.jrmp.interfaces.JRMPInvokerProxy.invoke(JRMPInvokerProxy.java:118)
at org.jboss.invocation.InvokerInterceptor.invokeInvoker(InvokerInterceptor.java:227)
at org.jboss.invocation.InvokerInterceptor.invoke(InvokerInterceptor.java:167)
at org.jboss.proxy.TransactionInterceptor.invoke(TransactionInterceptor.java:46)
at org.jboss.proxy.SecurityInterceptor.invoke(SecurityInterceptor.java:55)
at org.jboss.proxy.ejb.HomeInterceptor.invoke(HomeInterceptor.java:169)
at org.jboss.proxy.ClientContainer.invoke(ClientContainer.java:86)
at $Proxy0.create(Unknown Source)
at test.client.main(client.java:56)
Caused by: java.rmi.ServerException: EJBException:; nested exception is: 
javax.ejb.EJBException: getGeneratedKeys returned an empty ResultSet
at org.jboss.ejb.plugins.LogInterceptor.handleException(LogInterceptor.java:352)
at org.jboss.ejb.plugins.LogInterceptor.invokeHome(LogInterceptor.java:125)
at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invokeHome(ProxyFactoryFinderInterceptor.java:93)
at org.jboss.ejb.EntityContainer.internalInvokeHome(EntityContainer.java:508)
at org.jboss.ejb.Container.invoke(Container.java:894)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:141)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:80)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:72)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:249)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:644)
at org.jboss.invocation.jrmp.server.JRMPInvoker$MBeanServerAction.invoke(JRMPInvoker.java:805)
at org.jboss.invocation.jrmp.server.JRMPInvoker.invoke(JRMPInvoker.java:406)
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 sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:294)
at sun.rmi.transport.Transport$1.run(Transport.java:153)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
at java.lang.Thread.run(Thread.java:595)
Caused by: javax.ejb.EJBException: getGeneratedKeys returned an empty ResultSet
at org.jboss.ejb.plugins.cmp.jdbc.keygen.JDBCMySQLCreateCommand.executeInsert(JDBCMySQLCreateCommand.java:87)
at org.jboss.ejb.plugins.cmp.jdbc.JDBCAbstractCreateCommand.performInsert(JDBCAbstractCreateCommand.java:308)
at org.jboss.ejb.plugins.cmp.jdbc.JDBCAbstractCreateCommand.execute(JDBCAbstractCreateCommand.java:138)
at org.jboss.ejb.plugins.cmp.jdbc.JDBCStoreManager.createEntity(JDBCStoreManager.java:572)
at org.jboss.ejb.plugins.CMPPersistenceManager.createEntity(CMPPersistenceManager.java:222)
at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.createEntity(CachedConnectionInterceptor.java:266)
at org.jboss.ejb.EntityContainer.createHome(EntityContainer.java:766)
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.jboss.invocation.Invocation.performCall(Invocation.java:345)
at org.jboss.ejb.EntityContainer$ContainerInterceptor.invokeHome(EntityContainer.java:1113)
at org.jboss.ejb.plugins.AbstractInterceptor.invokeHome(AbstractInterceptor.java:90)
at org.jboss.ejb.plugins.EntitySynchronizationInterceptor.invokeHome(EntitySynchronizationInterceptor.java:192)
at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invokeHome(CachedConnectionInterceptor.java:212)
at org.jboss.ejb.plugins.AbstractInterceptor.invokeHome(AbstractInterceptor.java:90)
at org.jboss.ejb.plugins.EntityInstanceInterceptor.invokeHome(EntityInstanceInterceptor.java:117)
at org.jboss.ejb.plugins.EntityLockInterceptor.invokeHome(EntityLockInterceptor.java:61)
at org.jboss.ejb.plugins.EntityCreationInterceptor.invokeHome(EntityCreationInterceptor.java:28)
at org.jboss.ejb.plugins.CallValidationInterceptor.invokeHome(CallValidationInterceptor.java:41)
at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:109)
at org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCMT.java:335)
at org.jboss.ejb.plugins.TxInterceptorCMT.invokeHome(TxInterceptorCMT.java:146)
at org.jboss.ejb.plugins.SecurityInterceptor.invokeHome(SecurityInterceptor.java:116)
at org.jboss.ejb.plugins.LogInterceptor.invokeHome(LogInterceptor.java:121)
... 25 more
getGeneratedKeys returned an empty ResultSet.I use google to search it , without any solution.it is a common problem.Wish the real expert can help.