diff --git a/message.xml b/message.xml
index cdcebac..f2b0e0e 100644
--- a/message.xml
+++ b/message.xml
@@ -2,7 +2,7 @@
 <!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
 this repository contains the full copyright notices and license terms. -->
 <tryton>
-    <data group="1">
+    <data grouped="1">
         <record model="ir.message" id="invalid_production_state">
             <field name="text">You can not create an operation for Production "%(production)s".</field>
         </record>