How to fix workItems with creationDate main field set to none, but with a correct creationDate in the History?

 one way is to set the creation date as system property date so that both the  dates I.e. on the work item and history are in sync. 

            DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
            Date date = new Date();
            IWorkItem wi=client.findWorkItemById(workItemId, IWorkItem.FULL_PROFILE, monitor);
               IWorkItemWorkingCopyManager manager= client.getWorkItemWorkingCopyManager();
               manager.connect(handle, IWorkItem.FULL_PROFILE, monitor);
                wc = manager.getWorkingCopy(handle);
            wi.setCreationDate(new Timestamp(date.getTime()));
            wc.save(null);

This should update the workitem's creation date as system date.