[jQuery] UI Datepicker Regional

Hello all,
I can't get the regional settings (language etc) to work with my
datepicker - the changes I have made other than that are:
$("#dateInput").datepicker({
    closeText: 'Luk',
    prevText: '« M',
    nextText: 'M »',
    currentText: 'M',
    navigationAsDateFormat: true,
    firstDay: 1,
    duration: 'fast',
    showAnim: 'fadeIn'
});
What do I put in there to set the region?
Thanx