if (document.images) {
//main nav
	nav1 = new Image;		nav1a = new Image;
	nav2 = new Image;		nav2a = new Image;
	nav3 = new Image;		nav3a = new Image;
	nav4 = new Image;		nav4a = new Image;
	nav5 = new Image;		nav5a = new Image;
	nav6 = new Image;		nav6a = new Image;
	
	nav1.src = "gfx/nav1.jpg"; nav1a.src = "gfx/nav1a.jpg";
	nav2.src = "gfx/nav2.jpg"; nav2a.src = "gfx/nav2a.jpg";
	nav3.src = "gfx/nav3.jpg"; nav3a.src = "gfx/nav3a.jpg";
	nav4.src = "gfx/nav4.jpg"; nav4a.src = "gfx/nav4a.jpg";
	nav5.src = "gfx/nav5.jpg"; nav5a.src = "gfx/nav5a.jpg";
	nav6.src = "gfx/nav6.jpg"; nav6a.src = "gfx/nav6a.jpg";
	
		
function chgImg(imgField,newImg) {
	if (document.images) {
		document[imgField].src= eval(newImg + ".src")
		}
	}
}