Put this at the very end of environment.rb (*after* the 'end' of the Rails::Initializer.run method):
CalendarDateSelect.format = :finnish
Now I remember I had the same problem when trying to use British- format dates (dd/mm/yyyy). Try this as a starting point: http://groups.google.com/group/calendar_date_select/browse_thread/thread/86d0451c515c2074/9f93a4a5976119fa That discussion is getting old now, so it might be worth looking through the calendar_date_select group to see if there have been changes to Rails and/or the plugin that you need to know about. It's still working for me with Rails 2.2, though.
And more info here:
