Capturar mensagem do banco de dados com hibernate

Programação Java
#1

Alguém sabe como pegar com hibernate a mensagem de uma exception que veio do banco de dados, exemplo:

Caused by: org.firebirdsql.jdbc.FBSQLException: GDS Exception. 335544665. violation of PRIMARY or UNIQUE KEY constraint "INTEG_141" on table "CTRC"
        at org.firebirdsql.jdbc.AbstractPreparedStatement.internalExecute(AbstractPreparedStatement.java:712)
        at org.firebirdsql.jdbc.AbstractPreparedStatement.executeUpdate(AbstractPreparedStatement.java:172)
        at org.hibernate.jdbc.NonBatchingBatcher.addToBatch(NonBatchingBatcher.java:23)
        at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2247)

isso aparece no console do netbeans quando da um ex.printStackTrace();
só que se eu der uma mensagem com ex.getCause().getMessage() vem a seguinte mensagem:

log4j:WARN No appenders could be found for logger (org.hibernate.cfg.annotations.Version).
log4j:WARN Please initialize the log4j system properly.
org.hibernate.exception.GenericJDBCException: could not insert: [br.com.maxiconsystems.embarcador.modelo.Ctrc]
        at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
        at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
        at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
        at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2267)
        at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2660)
        at org.hibernate.action.EntityInsertAction.execute(EntityInsertAction.java:56)
        at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:250)
        at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:234)
        at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:141)
        at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:298)
        at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
        at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000)
        at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:338)
        at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:106)
        at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:54)
        at br.com.maxiconsystems.embarcador.util.GenericDAO.persist(GenericDAO.java:35)
        at br.com.maxiconsystems.embarcador.frames.LanCtrc.toolBarSalvar(LanCtrc.java:5275)
        at br.com.maxiconsystems.componentes.MToolBar$2.actionPerformed(MToolBar.java:87)
        at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1636)
        at javax.swing.JComponent.processKeyBinding(JComponent.java:2849)
        at javax.swing.KeyboardManager.fireBinding(KeyboardManager.java:267)
        at javax.swing.KeyboardManager.fireKeyboardAction(KeyboardManager.java:216)
        at javax.swing.JComponent.processKeyBindingsForAllComponents(JComponent.java:2926)
        at javax.swing.JComponent.processKeyBindings(JComponent.java:2906)
        at javax.swing.JComponent.processKeyEvent(JComponent.java:2812)
        at java.awt.Component.processEvent(Component.java:5818)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4413)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848)
        at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:697)
        at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:962)
        at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:834)
        at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:661)
        at java.awt.Component.dispatchEventImpl(Component.java:4285)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Window.dispatchEventImpl(Window.java:2440)
        at java.awt.Component.dispatchEvent(Component.java:4243)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)

só que com essa segunda parte da exception fica complicado de saber o que realmente aconteceu, precisa pegar o erro que veio do banco.

#2