DTnow = new Date();
Year  = DTnow.getYear();
Month = DTnow.getMonth();
DayN  = DTnow.getDay(); 
DayM  = DTnow.getDate();

if (Year < 1000) Year += 1900;  

var Mths = new Array("Stycznia","Lutego","Marca","Kwietnia","Maja","Czerwca","Lipca","Sierpnia","Września","Października","Listopada","Grudnia");
var DoW = new Array("Niedziela","Poniedziałek","Wtorek","Środa","Czwartek","Piątek","Sobota");

document.write(DoW[DayN] + ",  " + DayM + " " + Mths[Month] + " " + Year);