diff --git a/addons/product/product.py b/addons/product/product.py
index b6a58fcd1e8..27cd4249a60 100644
--- a/addons/product/product.py
+++ b/addons/product/product.py
@@ -657,9 +657,9 @@ class product_product(osv.osv):
                 # Performing a quick memory merge of ids in Python will give much better performance
                 ids = set()
                 ids.update(self.search(cr, user, args + [('default_code',operator,name)], limit=limit, context=context))
-                if len(ids) < limit:
+                if not limit or len(ids) < limit:
                     # we may underrun the limit because of dupes in the results, that's fine
-                    ids.update(self.search(cr, user, args + [('name',operator,name)], limit=(limit-len(ids)), context=context))
+                    ids.update(self.search(cr, user, args + [('name',operator,name)], limit=(limit and (limit-len(ids)) or False) , context=context))
                 ids = list(ids)
             if not ids:
                 ptrn = re.compile('(\[(.*?)\])')