diff --git a/tryton/common/date_widget.py b/tryton/common/date_widget.py
index 5362d76bf0..757a7489ad 100644
--- a/tryton/common/date_widget.py
+++ b/tryton/common/date_widget.py
@@ -42,6 +42,7 @@ mapping = {
     '%H': ('  ', '([ 0-1][ 0-9]|[ 2][ 0-4])'),
     '%M': ('  ', '([ 0-5][ 0-9]|[ 6][ 0])'),
     '%S': ('  ', '([ 0-5][ 0-9]|[ 6][ 0])'),
+    '%p': ('  ', '[ AP][ M]'),
 }
 
 class DateEntry(gtk.Entry):