diff --git a/product/ERP5/mixin/document.py b/product/ERP5/mixin/document.py
index 8772a07a431d853914d1da4ff55b5415d48b0525..1cb3b55987f4bac35bb297193b18330bb3552c6f 100644
--- a/product/ERP5/mixin/document.py
+++ b/product/ERP5/mixin/document.py
@@ -27,7 +27,7 @@
 #
 ##############################################################################
 from Products.CMFCore.utils import getToolByName
-from AccessControl import ClassSecurityInfo
+from AccessControl import ClassSecurityInfo, Unauthorized
 from Products.ERP5Type import Permissions
 from OFS.Image import Pdata
 from cStringIO import StringIO