var imagesPath = 'images/nav/';
var preloadFlag = false;

function preloadImages() {
	if (document.images) {
		pre_home = newImage('images/nav/home_1.gif');
		pre_about = newImage('images/nav/about_1.gif');
		pre_services = newImage('images/nav/services_1.gif');
		pre_clients = newImage('images/nav/clients_1.gif');
		pre_contact = newImage('images/nav/contact_1.gif');
		preloadFlag = true;
	}
}

function swapNav(el,state){
	if(preloadFlag == true){
		var objEl;
		objEl = (document.getElementById) ? document.getElementById(el) : objEl = document.images[el];
		if(document.getElementById || document.images){
			if(state=='on'){
				objEl.src = imagesPath + el + '_1.gif';
			}else if(state=='off'){
				objEl.src = imagesPath + el + '_0.gif';
			}
		}
	}
}

function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}