Method getSource from an older version of the Hibernate Core is referenced. It is stated within the compatibility matrix that Hibernate Validator 3.1.0.CR1 is compatible only with Hibernate Core 3.3.x version(s). Exception in thread "main" java.lang.NoSuchMethodError: org.hibernate.event.PreInsertEvent.getSource()Lorg/hibernate/engine/SessionImplementor; at org.hibernate.validator.event.ValidateEventListener.onPreInsert(ValidateEventListener.java:172) at org.hibernate.action.EntityInsertAction.preInsert(EntityInsertAction.java:178) at org.hibernate.action.EntityInsertAction.execute(EntityInsertAction.java:72) at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:279) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:263) at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:167) at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:321) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027) at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:365) at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:137)