Please, translate it into your languages if you need a calendar in your language. These are files in Deutch and French, use them as a pattern.

jQuery(function(a){a.datepicker.regional.de={closeText:"schließen",prevText:"<zurück",nextText:"Vor>",currentText:"heute",monthNames:["Januar","Februar","März","April","Mai","Juni","Juli","August","September","Oktober","November","Dezember"],monthNamesShort:["Jan","Feb","Mär","Apr","Mai","Jun","Jul","Aug","Sep","Okt","Nov","Dez"],dayNames:["Sonntag","Montag","Dienstag","Mittwoch","Donnerstag","Freitag","Samstag"],dayNamesShort:["So","Mo","Di","Mi","Do","Fr","Sa"],dayNamesMin:["So","Mo","Di","Mi","Do","Fr","Sa"],dateFormat:"dd.mm.yy",firstDay:1,isRTL:false};a.datepicker.setDefaults(a.datepicker.regional.de)});

jQuery(function(a){a.datepicker.regional.fr={closeText:"Fermer",prevText:"<Préc",nextText:"Suiv>",currentText:"Courant",monthNames:["Janvier","Février","Mars","Avril","Mai","Juin","Juillet","Août","Septembre","Octobre","Novembre","Décembre"],monthNamesShort:["Jan","Fév","Mar","Avr","Mai","Jun","Jul","Aoû","Sep","Oct","Nov","Déc"],dayNames:["Dimanche","Lundi","Mardi","Mercredi","Jeudi","Vendredi","Samedi"],dayNamesShort:["Dim","Lun","Mar","Mer","Jeu","Ven","Sam"],dayNamesMin:["Di","Lu","Ma","Me","Je","Ve","Sa"],dateFormat:"dd/mm/yy",firstDay:1,isRTL:false};a.datepicker.setDefaults(a.datepicker.regional.fr)});