Blink tag in IE vs Firefox

< html>
< head>
< script language="javascript">

/* IE, Firefox Browsers */
function blinkIt() {
if (!document.all) return;
else {
for(i=0;i< document.all.tags('blink').length;i++){
s=document.all.tags('blink')[i];
s.style.visibility=(s.style.visibility=='visible')?'hidden':'visible';
}
}
}
< /script>
< /head>
< body onLoad="javascript:setInterval('blinkIt()',500);">
< blink>Am i blinking ?< /blink>
< /body>
< /html>

Note:
In this example, 1 blank space added to all the tags opening and closing area. Before you execute this example, pls remove that space and execute it.