Hi
i experienced the same behaviour here. In my installation, all number values (days, week numbers, time) showed "NaN" and the weekdays were "undefined", everything else showed up as intended.

adding the line "Calendar._FD = 0;" (taken from the english language file) into the other language files fixed my problems. I checked the german and dutch language files as i'll only need those, maybe this fix works for the other languages as well.
greez