seguendo il consiglio di xinod... prova così


codice:
 

<HTML> 
<HEAD> 

<!-- Codice scaricato gratuitamente da HTML.it, il sito italiano sul Web publishing 
http://www.html.it --> 

<TITLE>Demo Dynamic HTML: esempio pratico </TITLE> 



</HEAD> 

<BODY bgcolor="white" > 


<FONT SIZE=5 COLOR="#0000FF" FACE="ARIAL">Dimostrazione di Cookie.
Ricarica questa pagina per una prova.</FONT> 

<SCRIPT LANGUAGE="JavaScript"> 
function parseCookie() { 
// Separate each cookie. 
var cookieList = document.cookie.split("; "); 
// Array for each cookie in cookieList 
var cookieArray = new Array(); 
for (var i = 0; i < cookieList.length; i++) { 
// Separate name-value pairs. 
var name = cookieList[i].split("="); 
// Decode and add to cookie array. 
cookieArray[unescape(name[0])] = unescape(name[1]); 
} 
return cookieArray; 
} 

// This code requires the parseCookie function. 

function setCookie(visits) { 
/* This routine sets up the cookie by setting its value 
to the number of visits and setting its expiration date 
to 1 year from now. */ 
var expireDate = new Date(); 
var today = new Date(); 
// Set an expiration date in the future. 
expireDate.setDate(365 + expireDate.getDate()); 
// Save the number of visits. 
document.cookie = "Visits=" + visits + "; expires=" + 
expireDate.toGMTString() + ";"; 
// Save today's time and date as the last visit. 
document.cookie = "LastVisit=" + 
escape(today.toGMTString()) + 
"; expires=" + expireDate.toGMTString() + ";"; 
} 

if ("" == document.cookie) { 
// Initialize the cookie. 
setCookie(1); 
document.write("<H2>Questa è la tua prima visita in questa pagina</H2>"); 
} 
else { 
// Parse the cookie. 
var cookies = parseCookie(); 

// Output the Welcome Back message, and increment the 
// visit counter. 
document.write("<H2>Bentornato! tu ci ha visitato " + 
(parseInt(cookies.Visits)+1) + " volte!</H2>"); 
document.write("<H3>La tua ultima visita risale a " + 
cookies.LastVisit + ".</H3>"); 
// Replace existing cookie with an updated one. 
setCookie(cookies.Visits); 
} 
</SCRIPT> 

</body> 
</html>