// Comprobar fechas

function comprobar_fecha(f) {

var parsedDate = f.split ("/");
   if (parsedDate.length != 3) return false;
var day, month, year;
   day = eval(parsedDate[0]);
   month = eval(parsedDate[1])-1;
   year = eval(parsedDate[2]);

var objDate = new Date (year, month, day, 0, 0, 0, 0);

if (month != objDate.getMonth()) return false;
   if (day != objDate.getDate()) return false;
   if (year != objDate.getFullYear()) return false;
   return true;
}