diff --git a/trytond/ir/property.py b/trytond/ir/property.py
index 26ff417a03..250aa0541e 100644
--- a/trytond/ir/property.py
+++ b/trytond/ir/property.py
@@ -96,14 +96,14 @@ class Property(OSV):
         model_field_obj = self.pool.get('ir.model.field')
         field_id = model_field_obj.search(cursor, user, [
             ('name', '=', name),
-            ('model', '=', model),
+            ('model.model', '=', model),
             ], limit=1, context=context)[0]
 
         property_ids = self.search(cursor, user, [
             ('field', '=', field_id),
             ('res', '=', name + ',' + str(res_id)),
             ], context=context)
-        self.unlink(cursor, property_ids, context=context)
+        self.unlink(cursor, user, property_ids, context=context)
 
         default_id = self.search(cursor, user, [
             ('field', '=', field_id),
diff --git a/trytond/osv/fields.py b/trytond/osv/fields.py
index 189118f294..f973ad8ce5 100644
--- a/trytond/osv/fields.py
+++ b/trytond/osv/fields.py
@@ -617,7 +617,7 @@ class Property(Function):
 
     def __init__(self, obj_prop, **args):
         function.__init__(self, '', False, self._fnct_write,
-                (obj_prop, ), **args)
+                obj_prop, **args)
 
     def get(self, cursor, obj, ids, name, user=None, offset=0, context=None,
             values=None):