function activate_menu(menu_id) {
	
	document.menu_image_swap[menu_id] = document.getElementById('menu_item_' + menu_id).src;	
	document.getElementById('menu_item_' + menu_id).src = document.menu_image[menu_id].src;	
	
}

function deactivate_menu(menu_id) {
	
	document.getElementById('menu_item_' + menu_id).src = document.menu_image_swap[menu_id];
	
}

function preload_menu() {
	
	document.menu_image = new Array;
	document.menu_image_swap = new Array;
	document.menu_image[1] = new Image;
	document.menu_image[1].src = 'images/m1h.jpg';
	document.menu_image[2] = new Image;
	document.menu_image[2].src = 'images/m2h.jpg';
	document.menu_image[3] = new Image;
	document.menu_image[3].src = 'images/m3h.jpg';
	document.menu_image[4] = new Image;
	document.menu_image[4].src = 'images/m4h.jpg';
	document.menu_image[5] = new Image;
	document.menu_image[5].src = 'images/m5h.jpg';
	
}