if (document.images)
{
	preload_image = new Image();
	image_url = new Array();
	image_url[0] = "./images/nav_projects_over.png";
	image_url[1] = "./images/nav_members_over.png";
	image_url[2] = "./images/nav_contact_over.png";
	image_url[3] = "./images/nav_fridge_over.png";
	
	for(var i=0; i<4; i++) 
		preload_image.src = image_url[i];
}