Big thanks for your help. I change -ds.xml and use instead of "java:PostgresDS", "PostgresDS". In connection stage i don't have visible problems, but on | ResultSet rs = st.executeQuery("SELECT * FROM TestTable"); | i see Exception in thread "main" java.lang.reflect.UndeclaredThrowableException at $Proxy2.execute(Unknown Source) at org.ConnectFromJndi.main(ConnectFromJndi.java:36) Caused by: java.rmi.UnmarshalException: Error unmarshaling return; nested exception is: java.lang.ClassNotFoundException: org.postgresql.util.PSQLException (no security manager: RMI class loader disabled) 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:133) at org.jboss.invocation.InvokerInterceptor.invokeInvoker(InvokerInterceptor.java:365) at org.jboss.invocation.InvokerInterceptor.invoke(InvokerInterceptor.java:197) at org.jboss.proxy.ClientMethodInterceptor.invoke(ClientMethodInterceptor.java:74) at org.jboss.resource.adapter.jdbc.remote.StatementInterceptor.invoke(StatementInterceptor.java:58) at org.jboss.proxy.ClientContainer.invoke(ClientContainer.java:100) ... 2 more Caused by: java.lang.ClassNotFoundException: org.postgresql.util.PSQLException (no security manager: RMI class loader disabled) at sun.rmi.server.LoaderHandler.loadClass(Unknown Source) at sun.rmi.server.LoaderHandler.loadClass(Unknown Source) at java.rmi.server.RMIClassLoader$2.loadClass(Unknown Source) at java.rmi.server.RMIClassLoader.loadClass(Unknown Source) at sun.rmi.server.MarshalInputStream.resolveClass(Unknown Source) at java.io.ObjectInputStream.readNonProxyDesc(Unknown Source) at java.io.ObjectInputStream.readClassDesc(Unknown Source) at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source) at java.io.ObjectInputStream.readObject0(Unknown Source) at java.io.ObjectInputStream.readObject(Unknown Source) ... 11 more Maybe its my errors. After your message I am declined to not use jndi and will be limited simple JDBC to connection. It is a lot of complexities and not enough practical advantage in my case. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4038550#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...