jbpm4.4 spring3.0 hibernate 集成错误 急！急！急！could not initialize proxy - no Session

<bean id="springHelper" class="org.jbpm.pvm.internal.processengine.SpringHelper" />
  <bean id="processEngine" factory-bean="springHelper" factory-method="createProcessEngine" />
  
  <!-- 流程定义及管理 -->
  <bean id="repositoryService" factory-bean="processEngine"
  factory-method="getRepositoryService" />
  
  <!-- 控制流程实例 --> 
  <bean id="executionService" factory-bean="processEngine"
  factory-method="getExecutionService" />
  
  <bean id="historyService" factory-bean="processEngine"
  factory-method="getHistoryService" />
  
  <bean id="managementService" factory-bean="processEngine"
  factory-method="getManagementService" />
  
  <bean id="identityService" factory-bean="processEngine"
  factory-method="getIdentityService" />
  
  <bean id="taskService" factory-bean="processEngine"
  factory-method="getTaskService" />

当调用repositoryService.deleteDeploymentCascade(cmsWorkflowdeploy.getDeployId());方法时：
[CONSOLE_INFO] 2011-02-21 13:29:11,687 - org.hibernate.LazyInitializationException -86953 [http-8088-7] ERROR org.hibernate.LazyInitializationException - could not initialize proxy - no Session
org.hibernate.LazyInitializationException: could not initialize proxy - no Session

困扰了我三天了，一直没有找到一个合适的解决方法，您能提供点建议么？谢谢！期待您能快些回复....... 急！急！急！