--- a/taskapp/events/task.py	Fri Feb 26 14:39:47 2010 +0530
+++ b/taskapp/events/task.py	Fri Feb 26 15:00:01 2010 +0530
@@ -233,6 +233,8 @@
     task.status = "CM"
     task.save()
 
+    task.request_task.filter(is_replied=False).update(is_valid=False)
+
     ## generate notification appropriately using marked_by
     ## we also have to mark unread requests as invalid