diff --git a/addons/portal/portal.py b/addons/portal/portal.py
index c614148fcc6..a04521ca871 100644
--- a/addons/portal/portal.py
+++ b/addons/portal/portal.py
@@ -173,7 +173,8 @@ class users(osv.osv):
     _name = 'res.users'
     _inherit = 'res.users'
     _columns = {
-        'portal_id': fields.many2one('res.portal', string='Portal',
+        'portal_id': fields.many2one('res.portal', readonly=True,
+            string='Portal',
             help=_('If given, the portal defines customized menu and access rules')),
     }
     
diff --git a/addons/portal/portal_view.xml b/addons/portal/portal_view.xml
index 6a2a39b9c6d..5e3ae9211ca 100644
--- a/addons/portal/portal_view.xml
+++ b/addons/portal/portal_view.xml
@@ -66,7 +66,7 @@ added to (resp. removed from) the portal's users.
             <field name="arch" type="xml">
                 <page string="User" position="after">
                     <page string="Portal">
-                        <field name="portal_id" readonly="1"/>
+                        <field name="portal_id"/>
                     </page>
                 </page>
             </field>