diff --git a/tryton/gui/main.py b/tryton/gui/main.py
index 7054a53092..ee30987ea1 100644
--- a/tryton/gui/main.py
+++ b/tryton/gui/main.py
@@ -954,7 +954,7 @@ class Main(object):
             sb_id = self.sb_username.get_context_id('message')
             self.sb_username.push(sb_id, prefs.get('status_bar', ''))
             if prefs and 'language' in prefs:
-                translate.setlang(prefs['language'])
+                translate.setlang(prefs['language'], prefs.get('locale'))
                 CONFIG['client.lang'] = prefs['language']
                 CONFIG.save()
         self.window.present()
diff --git a/tryton/gui/window/view_form/view/list_gtk/parser.py b/tryton/gui/window/view_form/view/list_gtk/parser.py
index 91090606ff..60594ce483 100644
--- a/tryton/gui/window/view_form/view/list_gtk/parser.py
+++ b/tryton/gui/window/view_form/view/list_gtk/parser.py
@@ -329,10 +329,10 @@ class Boolean(Int):
 
 class Date(Char):
     server_format = DT_FORMAT
-    display_format = date_format()
 
     def __init__(self, field_name, model, treeview=None, attrs=None,
             window=None):
+        self.display_format = date_format()
         self.field_name = field_name
         self.model = model
         self.attrs = attrs or {}
@@ -359,7 +359,12 @@ class Date(Char):
 
 class Datetime(Date):
     server_format = DHM_FORMAT
-    display_format = date_format() + ' ' + HM_FORMAT
+
+    def __init__(self, field_name, model, treeview=None, attrs=None,
+            window=None):
+        self.display_format = date_format() + ' ' + HM_FORMAT
+        return super(Datetime, self).__init__(field_name, model,
+                treeview=treeview, attrs=attrs, window=window)
 
     def get_textual_value(self, model):
         value = model[self.field_name].get_client(model)