$(document).ready(function() {

	$("ul#top_nav li").hover(function() { //Hover over event on list item
		if (this.className != "on") {	// Only show if not active item
			$(this).css({ 'background' : 'background: URL(images/nav_button_off.png) no-repeat'}); //Add background color and image on hovered list item
			$(this).find("span").show(); //Show the subnav
		}
	} , function() { //on hover out...
		if (this.className != "on") {
			$(this).css({ 'background' : 'background: URL(images/nav_button_off.png) no-repeat'}); //Ditch the background
			$(this).find("span").hide(); //Hide the subnav
		}
	});

});