what does this code do

[Tommy]

<SCRIPT LANGUAGE="JavaScript">
<!--
var agt=navigator.userAgent.toLowerCase();
var is_major=parseInt(navigator.appVersion);
var is_minor=parseFloat(navigator.appVersion);
var is_nav=((agt.indexOf('mozilla')!=-1)&&(agt.indexOf('spoofer')==-1)&&(agt.indexOf('compatible')==-1) && (agt.indexOf('opera')==-1)&&(agt.indexOf('webtv')==-1));
var is_ie=(agt.indexOf('msie')!=-1);
if(is_ie){var agt_ie=agt.substring(agt.indexOf('msie')+5); is_major=parseInt(agt_ie); is_minor=parseFloat(agt_ie);}
var is_dom2=(document.getElementById);
var is_http=(window.location.protocol.indexOf('http')==0);
// Browser detect
if( is_minor < 3.5 )
alert( "This page will not function properly in your browser.\n\nYour browser is very old. Please upgrade your browser to version 4 or later.\n\nOr request the webmaster (of this page) to change their browser compatibility setting in Cool Page to version 3 browsers." );
else
{
if( is_nav && is_minor < 5.0 )
window.location.replace( 'girlfriends_nn4.html' + window.location.search );
}

//-->

[DangerDave]

Browser Sniffer and Redirector

replaces elements dependant on the browser viewing the page

DD