raw material supplied in purchase receipt should be a no copy field

stock/doctype/purchase_receipt_item/purchase_receipt_item.txt

@@ -2,7 +2,7 @@
  {
   "creation": "2013-02-07 08:28:23", 
   "docstatus": 0, 
-  "modified": "2013-02-08 14:06:15", 
+  "modified": "2013-02-11 08:13:11", 
   "modified_by": "Administrator", 
   "owner": "Administrator"
  }, 
@@ -385,6 +385,7 @@
   "hidden": 1, 
   "in_filter": 0, 
   "label": "Raw Materials Supplied Cost", 
+  "no_copy": 1, 
   "oldfieldname": "rm_supp_cost", 
   "oldfieldtype": "Currency", 
   "options": "Company:company:default_currency",