diff --git a/product/ERP5/Document/AccountingTransaction.py b/product/ERP5/Document/AccountingTransaction.py
index bcd7d33889b710e5190af13222170c12c56c362e..e4262336d424d8dca72a4db1ca9b86ea31932124 100644
--- a/product/ERP5/Document/AccountingTransaction.py
+++ b/product/ERP5/Document/AccountingTransaction.py
@@ -32,6 +32,7 @@ from Products.ERP5Type import Permissions, PropertySheet, Constraint, Interface
 from Products.CMFCore.utils import getToolByName
 
 from Products.ERP5.Document.Delivery import Delivery
+from Acquisition import aq_base
 
 class AccountingTransaction(Delivery):
     """
@@ -112,7 +113,15 @@ class AccountingTransaction(Delivery):
         if prop:
           text_list.append(str(prop))
       return ' '.join(text_list)
-  
+
+    def manage_afterClone(self, transaction):
+        Delivery.manage_afterClone(self, transaction)
+        #Clean some properties
+        if getattr(aq_base(self), 'source_reference', None) is not None:
+          delattr(self, 'source_reference')
+        if getattr(aq_base(self), 'destination_reference', None) is not None:
+          delattr(self, 'destination_reference')
+
 # Compatibility
 # It may be necessary to create an alias after removing the Transaction class
 # Products.ERP5Type.Document.Transaction = AccountingTransaction