var month = new Array("Enero", "Febrero", "Marzo", "Abril", "Mayo", "Junio", "Julio", "Agosto", "Septiembre", "Octubre", "Noviembre", "Diciembre");
var day = new Array("Domingo", "Lunes", "Martes", "Miércoles", "Jueves", "Viernes", "Sábado", "Domingo");
var today = new Date();

var year = today.getYear();
date = day[today.getDay()] + ", "; 
date += today.getDate() +  "  de   "; 
date += month[today.getMonth()] +   "  de  "; 
date +=  (year <= 99? "19" + year : (year <= 199? 1900 + year : year));

document.write(date  +   "<BR>" );