Hashtable parms = new Hashtable();
parms.put(Context.INITIAL_CONTEXT_FACTORY, com.ibm.websphere.naming.WsnInitialContextFactory.class.getName());
Context context = new InitialContext(parms);
DataSource ds= (DataSource)javax.rmi.PortableRemoteObject.narrow(context.lookup("jdbc/ds"), javax.sql.DataSource.class);