We are using JPA in our web application with Hibernate 3.1 as the persistence provider. When our application starts up in the WAS cluster, the following exception is thrown in multiple nodes. But after that it works fine. What causes this error?

Thanks,
Seema

Caused by: java.util.ConcurrentModificationException: concurrent access to HashMap attempted by Thread[ORB.thread.pool : 1,5,main]
at java.util.HashMap.onExit(HashMap.java:226)
at java.util.HashMap.transfer(HashMap.java:690)
at java.util.HashMap.resize(HashMap.java:676)
at java.util.HashMap.addEntry(HashMap.java:1049)
at java.util.HashMap.put(HashMap.java:561)
at org.hibernate.reflection.java.JavaXFactory.getXMethod(JavaXFactory.java:220)
at org.hibernate.reflection.java.JavaXClass.getDeclaredMethods(JavaXClass.java:100)
at org.hibernate.validator.ClassValidator.initValidator(ClassValidator.java:174)
at org.hibernate.validator.ClassValidator.<init>(ClassValidator.java:110)
at org.hibernate.validator.ClassValidator.<init>(ClassValidator.java:98)
at org.hibernate.validator.ClassValidator.<init>(ClassValidator.java:92)
at org.hibernate.validator.ClassValidator.<init>(ClassValidator.java:84)
at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile(AnnotationConfiguration.java:325)
at org.hibernate.cfg.Configuration.buildMappings(Configuration.java:1034)
at org.hibernate.ejb.Ejb3Configuration.buildMappings(Ejb3Configuration.java:1015)
at org.hibernate.ejb.EventListenerConfigurator.configure(EventListenerConfigurator.java:154)
at org.hibernate.ejb.Ejb3Configuration.createEntityManagerFactory(Ejb3Configuration.java:751)
at org.hibernate.ejb.Ejb3Configuration.createContainerEntityManagerFactory(Ejb3Configuration.java:350)
at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:119)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:218)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:251)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1198)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1167)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:427)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:249)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:155)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:246)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:160)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:267)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:110)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1095)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:857)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:423)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:249)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:155)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:246)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:160)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:291)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:352)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:122)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:76)
at com.adesa.business.framework.context.ContextHolder.initializeContext(ContextHolder.java:145)
at com.adesa.business.framework.context.ContextHolder.getInstance(ContextHolder.java:110)
at com.adesa.business.framework.locator.ServiceLocator.lookup(ServiceLocator.java:88)
at com.adesa.business.security.ejb.SecurityBean.loadStore(SecurityBean.java:96)
at com.adesa.business.security.ejb.EJSRemoteStatelessSecurity_036d6978.loadStore(Unknown Source)
at com.adesa.business.security.ejb._EJSRemoteStatelessSecurity_036d6978_Tie.loadStore(_EJSRemoteStatelessSecurity_036d6978_Tie.java:211)
at com.adesa.business.security.ejb._EJSRemoteStatelessSecurity_036d6978_Tie._invoke(_EJSRemoteStatelessSecurity_036d6978_Tie.java:102)
at com.ibm.CORBA.iiop.ServerDelegate.dispatchInvokeHandler(ServerDelegate.java:621)
at com.ibm.CORBA.iiop.ServerDelegate.dispatch(ServerDelegate.java:474)
at com.ibm.rmi.iiop.ORB.process(ORB.java:503)
at com.ibm.CORBA.iiop.ORB.process(ORB.java:1571)
at com.ibm.rmi.iiop.Connection.respondTo(Connection.java:2701)
at com.ibm.rmi.iiop.Connection.doWork(Connection.java:2575)
at com.ibm.rmi.iiop.WorkUnitImpl.doWork(WorkUnitImpl.java:62)
at com.ibm.ejs.oa.pool.PooledThread.run(ThreadPool.java:118)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1473)

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