function validaCPF(cpf)
{
    
	cpf = remove(cpf, ".");
    cpf = remove(cpf, "-");
	
	if (cpf.length < 11)
        return false;
        
    var nonNumbers = /\D/;
    
    if (nonNumbers.test(cpf))
        return false;
        
    if (cpf == "00000000000" || cpf == "11111111111" || cpf == "22222222222" || cpf == "33333333333" || cpf == "44444444444" || cpf == "55555555555" || cpf == "66666666666" || cpf == "77777777777" || cpf == "88888888888" || cpf == "99999999999")
        return false;
    
    var a = [];
    var b = new Number;
    var c = 11;
    
    for (i=0; i<11; i++)
    {
        a[i] = cpf.charAt(i);
        if (i < 9)
            b += (a[i] * --c);
    }
    
    if ((x = b % 11) < 2)
        a[9] = 0;
    else
        a[9] = 11-x;
    
    b = 0;
    c = 11;
    
    for (y=0; y<10; y++)
        b += (a[y] * c--);
        
    if ((x = b % 11) < 2)
        a[10] = 0;
    else
        a[10] = 11-x;
        
    if ((cpf.charAt(9) != a[9]) || (cpf.charAt(10) != a[10]))
        return false;

    return true;
}

 function remove(str, sub) {
   i = str.indexOf(sub);
   r = "";
   if (i == -1) return str;
   r += str.substring(0,i) + remove(str.substring(i + sub.length), sub);
   return r;
 }