DetachedCriteria criteria = DetachedCriteria.forClass(Foo.class);
      criteria.add(Restrictions.eq("bar.id", 1l));
      criteria.getExecutableCriteria(s).list();
      tx.commit();

org.hibernate.QueryException: could not resolve property: bar.id of: org.hibernate.bugs.Foo
	at org.hibernate.persister.entity.AbstractPropertyMapping.propertyException(AbstractPropertyMapping.java:73)
	at org.hibernate.persister.entity.AbstractPropertyMapping.toColumns(AbstractPropertyMapping.java:88)
	at org.hibernate.persister.entity.BasicEntityPropertyMapping.toColumns(BasicEntityPropertyMapping.java:43)
	at org.hibernate.persister.entity.AbstractEntityPersister.toColumns(AbstractEntityPersister.java:1953)
	at org.hibernate.loader.criteria.CriteriaQueryTranslator.getColumns(CriteriaQueryTranslator.java:534)
	at org.hibernate.loader.criteria.CriteriaQueryTranslator.findColumns(CriteriaQueryTranslator.java:549)
	at org.hibernate.criterion.SimpleExpression.toSqlString(SimpleExpression.java:66)
	at org.hibernate.loader.criteria.CriteriaQueryTranslator.getWhereCondition(CriteriaQueryTranslator.java:424)
	at org.hibernate.loader.criteria.CriteriaJoinWalker.<init>(CriteriaJoinWalker.java:106)
	at org.hibernate.loader.criteria.CriteriaJoinWalker.<init>(CriteriaJoinWalker.java:75)
	at org.hibernate.loader.criteria.CriteriaLoader.<init>(CriteriaLoader.java:80)
	at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1985)
	at org.hibernate.internal.CriteriaImpl.list(CriteriaImpl.java:370)
	at org.hibernate.bugs.CriteriaAssociationTest.optionalTest(CriteriaAssociationTest.java:65)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.hibernate.testing.junit4.ExtendedFrameworkMethod.invokeExplosively(ExtendedFrameworkMethod.java:45)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
	at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:298)
	at org.junit.internal.runners.statements.FailOnTimeout$CallableStatement.call(FailOnTimeout.java:292)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.lang.Thread.run(Thread.java:748)