// Browser Detection
browser_name = navigator.appName;
browser_version = parseFloat(navigator.appVersion); 

	if (browser_name == "Netscape" && browser_version >= 3.0) { roll = 'true'; }
	else if (browser_name == "Microsoft Internet Explorer" && browser_version >= 4.0) { roll = 'true'; }
	else { roll = 'false'; }

// Preload images, if browser supports mouseovers
if (roll == 'true') {

var imglist = new Array (
	"images/top_menu/home_b.gif",
	"images/top_menu/product_b.gif",
    "images/top_menu/services_b.gif",
    "images/top_menu/spare_b.gif",
    "images/top_menu/faq_b.gif",
	"images/top_menu/aboutus_b.gif",
	"images/top_menu/contact_b.gif"
    );
	var imgs = new Array();

    var count;
    if (document.images)
    for (count=0; count<imglist.length; count++)
    {imgs[count]=new Image(); imgs[count].src=imglist[count];}
    }
function _on(img,ref) { if (roll == 'true') { document.images[img].src = ref; } }
function _off(img,ref)  { if (roll == 'true') { document.images[img].src = ref; } }