diff --git a/addons/stock/stock.py b/addons/stock/stock.py
index d84ede039d3..3f078ef9e41 100644
--- a/addons/stock/stock.py
+++ b/addons/stock/stock.py
@@ -475,7 +475,10 @@ class stock_tracking(osv.osv):
 
     def make_sscc(self, cr, uid, context=None):
         sequence = self.pool.get('ir.sequence').get(cr, uid, 'stock.lot.tracking')
-        return sequence + str(self.checksum(sequence))
+        try:
+            return sequence + str(self.checksum(sequence))
+        except Exception, e:
+            return sequence
 
     _columns = {
         'name': fields.char('Pack Reference', size=64, required=True, select=True),