diff --git a/product/ERP5/Document/Delivery.py b/product/ERP5/Document/Delivery.py
index 391ac5f8d5ce86c8d4b4085df01fd0491da0857e..8d37d6ce505a5c349aa312712d3db9c819c3f9ad 100755
--- a/product/ERP5/Document/Delivery.py
+++ b/product/ERP5/Document/Delivery.py
@@ -622,6 +622,8 @@ class Delivery(XMLObject):
         simulation_quantity = 0.
         for simulation_movement in movement.getDeliveryRelatedValueList():
           simulation_quantity += float(simulation_movement.getCorrectedQuantity())
+          if simulation_movement.getStartDate() != movement.getStartDate():
+            return 1
         if d_quantity != simulation_quantity:
           return 1
       return 0