It seems to be a bug with this month in Calendar view. The error: File "tryton/gui/window/view_form/view/calendar_gtk/parser.pyc", line 22, in on_page_changed
File "tryton/gui/window/view_form/view/calendar_gtk/calendar_.pyc", line 48, in update_domain File "tryton/gui/window/view_form/view/calendar_gtk/calendar_.pyc", line 42, in get_displayed_period
