function calculate(oCntrl) {
	month = document.frm.mes.selectedIndex;
	month = document.frm.mes.options[month].value;
	day = document.frm.dia.selectedIndex;
	day = document.frm.dia.options[day].value;
	var exd = new Date();
	var year=exd.getFullYear();

	var oyear=year

	var dob = " "+ year +", "+month + ",  "+day;
	var thenx = new Date(dob);

	var year=thenx.getYear();
	if (year<100) year="19" + thenx.getYear();
	else year=thenx.getYear();

	if (year > 1969) wyear=year;
	else {
		if (oyear<1900) {
			if (oyear>1800) {
				wrelyear= (eval(oyear)-1801)%(28);
				wyear = wrelyear+1981;
			}
			else wyear = 1970 
		}
		else
		if (oyear>1900) {wrelyear= (eval(oyear)-1901)%(28); 
			wyear= wrelyear+1985
		}
		else 
		if (oyear==1900) {
			wyear= 1990;
	   	}              
	}
	var dob = " "+ wyear +", "+month + ",  "+day;
	var thenx = new Date(dob);

	var theday = thenx.getDay()+1;
	var date=thenx.getDate();
	
	var weekday = new Array(6);
	weekday[1]="Domingo";
	weekday[2]="Lunes";
	weekday[3]="Martes";
	weekday[4]="Miercoles";
	weekday[5]="Jueves";
	weekday[6]="Viernes";
	weekday[7]="Sabado";
	//alert("Sorry!  That appears to be an invalid date! "+day+" ..."+date+"::"+oyear+"..."+year+" "+dob+"=="+wyear+".-.-"+thenx+" "+day+" "+month);
	if (day != date) alert('Porfavor seleccione el un día y fecha para su reservación.');
	else {
		dayborn = weekday[theday];
		dob = dayborn;
		//alert("El dia es: " + dob);
		cambia2(oCntrl,dob);
   }
}


function addOpt(oCntrl, iPos, sTxt, sVal){ 
     var selOpcion=new Option(sTxt, sVal); 
     eval(oCntrl.options[iPos]=selOpcion); 
   } 
 
   function cambia2(oCntrl,dob){ 
    while (oCntrl.length) oCntrl.remove(0); 
    switch (dob){ 
     case "Lunes":  
      addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
      addOpt(oCntrl,  01, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  02, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
      addOpt(oCntrl,  03, "14:00 a 15:00 hrs", "14:00 a 15:00 hrs"); 
	  addOpt(oCntrl,  04, "15:00 a 16:00 hrs", "15:00 a 16:00 hrs"); 
      addOpt(oCntrl,  05, "16:00 a 17:00 hrs", "16:00 a 17:00 hrs"); 
      addOpt(oCntrl,  06, "17:00 a 18:00 hrs", "17:00 a 18:00 hrs"); 
	  addOpt(oCntrl,  07, "18:00 a 19:00 hrs", "18:00 a 19:00 hrs"); 
      addOpt(oCntrl,  08, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  09, "20:00 a 21:00 hrs", "20:00 a 21:00 hrs"); 
	  addOpt(oCntrl,  10, "21:00 a 22:00 hrs", "21:00 a 22:00 hrs"); 
      addOpt(oCntrl,  11, "22:00 a 23:00 hrs", "22:00 a 23:00 hrs"); 
      addOpt(oCntrl,  12, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs"); 
	  break; 
     case "Martes":
      addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
      addOpt(oCntrl,  01, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  02, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
      addOpt(oCntrl,  03, "14:00 a 15:00 hrs", "14:00 a 15:00 hrs"); 
	  addOpt(oCntrl,  04, "15:00 a 16:00 hrs", "15:00 a 16:00 hrs"); 
      addOpt(oCntrl,  05, "16:00 a 17:00 hrs", "16:00 a 17:00 hrs"); 
      addOpt(oCntrl,  06, "17:00 a 18:00 hrs", "17:00 a 18:00 hrs"); 
	  addOpt(oCntrl,  07, "18:00 a 19:00 hrs", "18:00 a 19:00 hrs"); 
      addOpt(oCntrl,  08, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  09, "20:00 a 21:00 hrs", "20:00 a 21:00 hrs"); 
	  addOpt(oCntrl,  10, "21:00 a 22:00 hrs", "21:00 a 22:00 hrs"); 
      addOpt(oCntrl,  11, "22:00 a 23:00 hrs", "22:00 a 23:00 hrs"); 
      addOpt(oCntrl,  12, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs"); 
	  break; 
     case "Miercoles":
	  addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
      addOpt(oCntrl,  01, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  02, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
      addOpt(oCntrl,  03, "14:00 a 15:00 hrs", "14:00 a 15:00 hrs"); 
	  addOpt(oCntrl,  04, "15:00 a 16:00 hrs", "15:00 a 16:00 hrs"); 
      addOpt(oCntrl,  05, "16:00 a 17:00 hrs", "16:00 a 17:00 hrs"); 
      addOpt(oCntrl,  06, "17:00 a 18:00 hrs", "17:00 a 18:00 hrs"); 
	  addOpt(oCntrl,  07, "18:00 a 19:00 hrs", "18:00 a 19:00 hrs"); 
      addOpt(oCntrl,  08, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  09, "20:00 a 21:00 hrs", "20:00 a 21:00 hrs"); 
	  addOpt(oCntrl,  10, "21:00 a 22:00 hrs", "21:00 a 22:00 hrs"); 
      addOpt(oCntrl,  11, "22:00 a 23:00 hrs", "22:00 a 23:00 hrs"); 
      addOpt(oCntrl,  12, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs"); 
	  break; 
	  case "Jueves": 
	  addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
      addOpt(oCntrl,  01, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  02, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
      addOpt(oCntrl,  03, "14:00 a 15:00 hrs", "14:00 a 15:00 hrs"); 
	  addOpt(oCntrl,  04, "15:00 a 16:00 hrs", "15:00 a 16:00 hrs"); 
      addOpt(oCntrl,  05, "16:00 a 17:00 hrs", "16:00 a 17:00 hrs"); 
      addOpt(oCntrl,  06, "17:00 a 18:00 hrs", "17:00 a 18:00 hrs"); 
	  addOpt(oCntrl,  07, "18:00 a 19:00 hrs", "18:00 a 19:00 hrs"); 
      addOpt(oCntrl,  08, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  09, "20:00 a 21:00 hrs", "20:00 a 21:00 hrs"); 
	  addOpt(oCntrl,  10, "21:00 a 22:00 hrs", "21:00 a 22:00 hrs"); 
      addOpt(oCntrl,  11, "22:00 a 23:00 hrs", "22:00 a 23:00 hrs"); 
      addOpt(oCntrl,  12, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs"); 
	  addOpt(oCntrl,  13, "00:00 a 01:00 hrs", "00:00 a 01:00 hrs"); 
	  break; 
	  case "Viernes":
	  addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
      addOpt(oCntrl,  01, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  02, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
      addOpt(oCntrl,  03, "17:00 a 18:00 hrs", "17:00 a 18:00 hrs"); 
	  addOpt(oCntrl,  04, "18:00 a 19:00 hrs", "18:00 a 19:00 hrs"); 
      addOpt(oCntrl,  05, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  06, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs");
	  addOpt(oCntrl,  07, "00:00 a 01:00 hrs", "00:00 a 01:00 hrs");
	  break; 
	  case "Sabado":
	  addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
	  addOpt(oCntrl,  01, "09:00 a 10:00 hrs", "09:00 a 10:00 hrs");
	  addOpt(oCntrl,  02, "10:00 a 11:00 hrs", "10:00 a 11:00 hrs");
	  addOpt(oCntrl,  03, "11:00 a 12:00 hrs", "11:00 a 12:00 hrs");
	  addOpt(oCntrl,  04, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  05, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
      addOpt(oCntrl,  06, "14:00 a 15:00 hrs", "14:00 a 15:00 hrs"); 
      addOpt(oCntrl,  07, "16:00 a 17:00 hrs", "16:00 a 17:00 hrs"); 
      addOpt(oCntrl,  08, "17:00 a 18:00 hrs", "17:00 a 18:00 hrs"); 
	  addOpt(oCntrl,  09, "18:00 a 19:00 hrs", "18:00 a 19:00 hrs"); 
      addOpt(oCntrl,  10, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  11, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs"); 
	  addOpt(oCntrl,  12, "00:00 a 01:00 hrs", "00:00 a 01:00 hrs");
	  break; 
	  case "Domingo":
	  addOpt(oCntrl,  00, ".: Hora :.", ".: Hora :."); 
      addOpt(oCntrl,  01, "09:00 a 10:00 hrs", "09:00 a 10:00 hrs");
	  addOpt(oCntrl,  02, "10:00 a 11:00 hrs", "10:00 a 11:00 hrs");
	  addOpt(oCntrl,  03, "11:00 a 12:00 hrs", "11:00 a 12:00 hrs");
	  addOpt(oCntrl,  04, "12:00 a 13:00 hrs", "12:00 a 13:00 hrs"); 
      addOpt(oCntrl,  05, "13:00 a 14:00 hrs", "13:00 a 14:00 hrs"); 
	  addOpt(oCntrl,  06, "19:00 a 20:00 hrs", "19:00 a 20:00 hrs"); 
      addOpt(oCntrl,  07, "20:00 a 21:00 hrs", "20:00 a 21:00 hrs"); 
	  addOpt(oCntrl,  08, "21:00 a 22:00 hrs", "21:00 a 22:00 hrs"); 
      addOpt(oCntrl,  09, "22:00 a 23:00 hrs", "22:00 a 23:00 hrs"); 
      addOpt(oCntrl,  10, "23:00 a 00:00 hrs", "23:00 a 00:00 hrs"); 
	  break; 
    } 
   }