function nav_highlight (which) {
	var previous_bg = which.style.backgroundImage.substring(4,which.style.backgroundImage.length-1);
	which.style.backgroundImage= "url('" + previous_bg.substring(0,previous_bg.lastIndexOf("1")) + "2.jpg')";
}
function nav_unhighlight (which) {
	var previous_bg = which.style.backgroundImage.substring(4,which.style.backgroundImage.length-1);
	which.style.backgroundImage= "url('" + previous_bg.substring(0,previous_bg.lastIndexOf("2")) + "1.jpg')";
}
function arrow (which) {
	document.getElementById("arrow_" + which).src='images/arrow.gif';
}
function unarrow_real (which) {
	document.getElementById("arrow_" + which).src='images/spacer.gif';
}
function unarrow (which) {
	setTimeout(function() {unarrow_real(which);},400);
}

function preload_nav_mouseovers () {
	imageObj = new Image();
	images = new Array();
	images[0]="images/layout/nav/home2.jpg"
	images[1]="images/layout/nav/about2.jpg"
	images[2]="images/layout/nav/education2.jpg"
	images[3]="images/layout/nav/connect2.jpg"
	images[4]="images/layout/nav/safezone2.jpg"
	images[5]="images/layout/nav/contacts2.jpg"

	for(i=0; i<images.length; i++) {
		imageObj.src=images[i];
	}
}