var ns4 = (navigator.appName.toLowerCase() == "netscape") ? true:false
var ie4 = !ns4

var activeMenu = ""
var mytimer

imageabout = new Image(182, 132);imageabout.src = 'images/about.gif';
imageabout_on = new Image(182, 132);imageabout_on.src = 'images/about_on.gif';
imagescience = new Image(182, 132);imagescience.src = 'images/science.gif';
imagescience_on = new Image(182, 132);imagescience_on.src = 'images/science_on.gif';
imagerd = new Image(182, 132);imagerd.src = 'images/rd.gif';
imagerd_on = new Image(182, 132);imagerd_on.src = 'images/rd_on.gif';
imageclinical = new Image(182, 132);imageclinical.src = 'images/clinical.gif';
imageclinical_on = new Image(182, 132);imageclinical_on.src = 'images/clinical_on.gif';
imagecontract = new Image(182, 132);imagecontract.src = 'images/contract.gif';
imagecontract_on = new Image(182, 132);imagecontract_on.src = 'images/contract_on.gif';

imagepress = new Image(182, 132);imagepress.src = 'images/press.gif';
imagepress_on = new Image(182, 132);imagepress_on.src = 'images/press_on.gif';
imagecareers = new Image(182, 132);imagecareers.src = 'images/careers.gif';
imagecareers_on = new Image(182, 132);imagecareers_on.src = 'images/careers_on.gif';
imagelinks = new Image(182, 132);imagelinks.src = 'images/links.gif';
imagelinks_on = new Image(182, 132);imagelinks_on.src = 'images/links_on.gif';
imagecontact = new Image(182, 132);imagecontact.src = 'images/contact.gif';
imagecontact_on = new Image(182, 132);imagecontact_on.src = 'images/contact_on.gif';
imagesitemap = new Image(182, 132);imagesitemap.src = 'images/sitemap.gif';
imagesitemap_on = new Image(182, 132);imagesitemap_on.src = 'images/sitemap_on.gif';

function doMouseOverMenu(menu)
{
	if (activeMenu != menu && activeMenu != "")
	{
		hideLayer("lay" + activeMenu)
		replace("lay" + activeMenu,"img" + activeMenu,"image" + activeMenu)
	}
	replace("lay" + menu,"img" + menu,"image" + menu + "_on")
	clearTimeout(mytimer)
	activeMenu = menu
	displayLayer("lay" + menu)
}

function makeDelay()
{
	mytimer = setTimeout("desactivateMenu()",1000);
}

function desactivateMenu()
{
	if (activeMenu != "") 
	{
		replace("lay" + activeMenu,"img" + activeMenu,"image" + activeMenu)
		hideLayer("lay" + activeMenu)
		activeMenu = ""
	}
}

function replace(lyr,what,bywhat) 
{ 
	document.images[what].src=eval(bywhat+".src")
	
	/*if (ie4) document.images[what].src=eval(bywhat+".src") ;
	if (ns4)
	{
		var obj
		obj = eval("document." + lyr)
		obj.document.images[what].src=eval(bywhat+".src") ;
		document.images[what].src=eval(bywhat+".src") ;
	}*/
}

function displayLayer(lyrName)
	{
		var obj
		if (ie4)
		{
			obj = eval(lyrName + ".style")
			obj.visibility = "visible"
		}
		if (ns4)
		{
			obj = eval("document." + lyrName)
			obj.visibility = "show"
		}
	}

function hideLayer(lyrName)
	{
		var obj
		if (ie4)
		{
			obj = eval(lyrName + ".style")
			obj.visibility = "hidden"
		}
		if (ns4)
		{
			obj = eval("document." + lyrName)
			obj.visibility = "hide"
		}
	}