arr = new Array(pre + "images/nav/aboutus_on.gif", pre + "images/nav/home_on.gif", pre + "images/nav/portfolio_on.gif", pre + "images/nav/services_on.gif", pre + "images/nav/downloads_on.gif" , pre + "images/nav/contactus_on.gif", pre + "images/nav/login_on.gif")
 for(i = 0; i < arr.length; i++) {
	newImg = new Image()
	newImg.src = arr[i]
 }
 
 function mOver(name, status)
 {
 	if(status ) document.images[name].src=pre + 'images/nav/' + name + '.gif'
 	else document.images[name].src=pre + 'images/nav/' + name + '_on.gif'	
 }

function swap(imageName, imageSrc)
{
	if (document.images){
		var i = document.images[imageName];
		if (i != null){
			i.src = pre+imageSrc;
		}
	}
}