function validar(formulario)
{

rut=form1.rut.value;
var count=0;
var count2=0;
var factor=2;
var suma=0;
var sum=0;
var digito=0;
count2=rut.length - 1;

while(count < rut.length)
{

sum = factor * (parseInt(rut.substr(count2,1))); 
suma = suma + sum;
sum=0;

count = count + 1;
count2 = count2 - 1;
factor = factor + 1;

if(factor > 7)
{
factor=2; 
} 

}

digito= 11 - (suma % 11)

if(digito==11)
{
digito=0;
}

if(digito==10)
{
	digito="K";
}

if(digito!=form1.digito.value)
{

	alert("Digito Verificador Incorrecto");
	form1.digito.value="";
	//document.digito.focus()
	return false
}

}