title: Toplink in clustered environment Exception
body: <p>*<strong>My application using Toplink with Spring and working fine...but when test application on  clustering environment it throwing exception ... 
  I have 2 nodes of servers (n1 and n2) when i shutdown serving node(suppose n1) it start throwing below exception... while n2 is serving requests *</strong>  </p>
  
  <p>DEBUG [controller.administrator.ManageCustomFieldsController] Trying to find handler for exception superclass [java.lang.Exception]
  java.lang.NullPointerException
          at oracle.toplink.internal.indirection.QueryBasedValueHolder.instantiate(QueryBasedValueHolder.java:62)
          at oracle.toplink.internal.indirection.QueryBasedValueHolder.instantiate(QueryBasedValueHolder.java:55)
          at oracle.toplink.internal.indirection.DatabaseValueHolder.getValue(DatabaseValueHolder.java:61)
          at oracle.toplink.indirection.IndirectList.buildDelegate(IndirectList.java:202)
          at oracle.toplink.indirection.IndirectList.getDelegate(IndirectList.java:359)
          at oracle.toplink.indirection.IndirectList.isEmpty(IndirectList.java:444)
          at com.soft.web.controller.administrator.ManageCustomFieldsController.transform(ManageCustomFieldsController.java:540)</p>
  
  <p>Any idea about it...?</p>