When i declare mac = 123, my internet explorer and firefox will keep refresh non-stop. And if i declare mac = getMacAddress it returns a value 1...

I'm able to do a document.write(getMacAddress()) and it would able to display the mac address nicely.

1) Why my explorer will keep refreshing non-stop when i code it manually with "123"

2) why is the document.write able to display out, and when i store it to the cookie, somehow it didnt mange to capture into the cookie and it return a value of "1".

Anyone help?

create_users.php

    <script language="JavaScript">

    function getMacAddress(){
    document.macaddressapplet.setSep( "-" );
    return (document.macaddressapplet.getMacAddress());
    }

    function setCookie(c_name,value) {
    document.cookie = c_name + "=" +escape(value);
    }

    //error checking
    //var mac = getMacAddress();
    var mac = "123";

    setCookie('cookie_name',mac);
    window.location = "checkAvailability.php";

    </script> 

checkAvailability.php

$javascript_cookie_value = isset($_COOKIE["cookie_name"]) ? $_COOKIE["cookie_name"] : 1;
mysql_query("INSERT INTO test (mac) VALUES ('$javascript_cookie_value')");