diff --git a/openerp/addons/base/ir/ir_attachment.py b/openerp/addons/base/ir/ir_attachment.py
index 6bf2266b412..43d13126f3b 100644
--- a/openerp/addons/base/ir/ir_attachment.py
+++ b/openerp/addons/base/ir/ir_attachment.py
@@ -242,7 +242,7 @@ class ir_attachment(osv.osv):
         # performed in batch as much as possible.
         ima = self.pool.get('ir.model.access')
         for model, targets in model_attachments.iteritems():
-            if model not in self.pool:
+            if not self.pool.get(model):
                 continue
             if not ima.check(cr, uid, model, 'read', False):
                 # remove all corresponding attachment ids