function loadCaptcha(){
	var img = document.getElementById("captcha");
	img.src = "include/captcha.png.php?" + Math.random();
}

function maxlenght(textarea, MaxLen){	
	if (textarea.value.length > MaxLen)
		textarea.value = textarea.value.substring(0,MaxLen);
	else
		document.getElementById('counter').innerHTML = MaxLen - parseInt(textarea.value.length);
}

function calcola(check){
	var campo = document.getElementById("totale");
	var totale = parseInt(campo.firstChild.nodeValue);
	var price = parseInt(check.value);	
	totale = (check.checked) ? totale + price : totale - price;
	var totStr = document.createTextNode(totale);
	campo.removeChild(campo.firstChild);
	campo.appendChild(totStr);
}