HELP ！！！help！！！manito！！有谁遇见过？？怎么解决？？？
HTTP Status 500 - identifier of an instance of com.myEdition.bean.ContentType was altered from 28 to 30; nested exception is org.hibernate.HibernateException: identifier of an instance of com.myEdition.bean.ContentType was altered from 28 to 30
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type Exception report
message identifier of an instance of com.myEdition.bean.ContentType was altered from 28 to 30; nested exception is org.hibernate.HibernateException: identifier of an instance of com.myEdition.bean.ContentType was altered from 28 to 30
description The server encountered an internal error that prevented it from fulfilling this request.
exception 
org.springframework.orm.hibernate3.HibernateSystemException: identifier of an instance of com.myEdition.bean.ContentType was altered from 28 to 30; nested exception is org.hibernate.HibernateException: identifier of an instance of com.myEdition.bean.ContentType was altered from 28 to 30
org.springframework.orm.hibernate3.SessionFactoryUtils.convertHibernateAccessException(SessionFactoryUtils.java:679)
org.springframework.orm.hibernate3.HibernateTransactionManager.convertHibernateAccessException(HibernateTransactionManager.java:793)
org.springframework.orm.hibernate3.HibernateTransactionManager.doCommit(HibernateTransactionManager.java:664)
org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:412)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:118)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
$Proxy6.findContentType(Unknown Source)
com.myEdition.action.ContenAction.release(ContenAction.java:37)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:601)
com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:441)
com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:280)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:243)
com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionI