Такой вопрос:
в маппинге есть такой вот composite-id:
<composite-id class="PK" name="drilldownPK">
<key-property name="currentColumnName" column="COLUMN_REP_1" type="java.lang.String"/>
<key-property name="drilldownColumnName" column="COLUMN_REP_2" type="java.lang.String"/>
</composite-id>

мне нужно вытянуть bag:
<bag name="drilldownReportRoles" lazy="false">
<key column="COLUMN_REP_1" not-null="true"/>
<one-to-many class="ReportRole"/>
</bag>

Кидает вполне обьяснимый эксепшен:
Invocation of init method failed; nested exception is org.hibernate.MappingException: Foreign key (FK9D5C38CD54DE7269:TABLE_NAME[COLUMN_REP_1])) must have same number of columns as the referenced primary key (META_DRILLDOWN [COLUMN_REP_1,COLUMN_REP_2])

тогда я сделал еще одну проперти в маппинге:
<property name="currentColumnName" column="COLUMN_REP_1" type="String" insert="false" update="false" access="field"/>

и изменил bag:
<bag name="drilldownReportRoles" lazy="false">
<key property-ref="currentColumnName" not-null="true"/>
<one-to-many class="ReportRole"/>
</bag>

теперь бросает ClassCastException:
java.lang.ClassCastException: java.lang.String
at org.hibernate.type.ComponentType.toLoggableString(ComponentType.java:377)
at org.hibernate.pretty.MessageHelper.collectionInfoString(MessageHelper.java:284)
at org.hibernate.loader.Loader.loadCollection(Loader.java:2001)
at org.hibernate.loader.collection.CollectionLoader.initialize(CollectionLoader.java:36)
at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:565)
at org.hibernate.event.def.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:60)
at org.hibernate.impl.SessionImpl.initializeCollection(SessionImpl.java:1716)
at org.hibernate.collection.AbstractPersistentCollection.forceInitialization(AbstractPersistentCollection.java:454)
at org.hibernate.engine.StatefulPersistenceContext.initializeNonLazyCollections(StatefulPersistenceContext.java:794)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:241)
at org.hibernate.loader.Loader.loadEntity(Loader.java:1860)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:48)
at org.hibernate.loader.entity.AbstractEntityLoader.load(AbstractEntityLoader.java:42)
at org.hibernate.persister.entity.AbstractEntityPersister.load(AbstractEntityPersister.java:3044)
at org.hibernate.event.def.DefaultLoadEventListener.loadFromDatasource(DefaultLoadEventListener.java:395)
at org.hibernate.event.def.DefaultLoadEventListener.doLoad(DefaultLoadEventListener.java:375)
at org.hibernate.event.def.DefaultLoadEventListener.load(DefaultLoadEventListener.java:139)
at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:179)
at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:103)
at org.hibernate.impl.SessionImpl.fireLoad(SessionImpl.java:878)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:795)
at org.hibernate.impl.SessionImpl.load(SessionImpl.java:788)
at org.springframework.orm.hibernate3.HibernateTemplate$3.doInHibernate(HibernateTemplate.java:508)
at org.springframework.orm.hibernate3.HibernateTemplate.execute(HibernateTemplate.java:372)
at org.springframework.orm.hibernate3.HibernateTemplate.load(HibernateTemplate.java:502)
at org.springframework.orm.hibernate3.HibernateTemplate.load(HibernateTemplate.java:496)
at com.dvision.business.dao.impl.DrilldownDaoImpl.findById(DrilldownDaoImpl.java:24)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:296)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:198)
at $Proxy9.findById(Unknown Source)
at com.dvision.business.dao.impl.DrilldownDaoImplTest.testFindById(DrilldownDaoImplTest.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at junit.framework.TestCase.runTest(TestCase.java:154)
at junit.framework.TestCase.runBare(TestCase.java:127)
at junit.framework.TestResult$1.protect(TestResult.java:106)
at junit.framework.TestResult.runProtected(TestResult.java:124)
at junit.framework.TestResult.run(TestResult.java:109)
at junit.framework.TestCase.run(TestCase.java:118)
at junit.framework.TestSuite.runTest(TestSuite.java:208)
at junit.framework.TestSuite.run(TestSuite.java:203)
at org.eclipse.jdt.internal.junit.runner.junit3.JUnit3TestReference.run(JUnit3TestReference.java:128)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)


Как быть??В чем моя ошибка?