if (document.images) {
nav0a = new Image; nav0b = new Image;
nav1a = new Image; nav1b = new Image;
nav2a = new Image; nav2b = new Image;
nav3a = new Image; nav3b = new Image;
nav4a = new Image; nav4b = new Image;
nav5a = new Image; nav5b = new Image;
nav6a = new Image; nav6b = new Image;
nav7a = new Image; nav7b = new Image;

nav0a.src = "gfx/nav_0a.jpg"; nav0b.src = "gfx/nav_0b.jpg";
nav1a.src = "gfx/nav_1a.jpg"; nav1b.src = "gfx/nav_1b.jpg";
nav2a.src = "gfx/nav_2a.jpg"; nav2b.src = "gfx/nav_2b.jpg";
nav3a.src = "gfx/nav_3a.jpg"; nav3b.src = "gfx/nav_3b.jpg";
nav4a.src = "gfx/nav_4a.jpg"; nav4b.src = "gfx/nav_4b.jpg";
nav5a.src = "gfx/nav_5a.jpg"; nav5b.src = "gfx/nav_5b.jpg";
nav6a.src = "gfx/nav_8a.jpg"; nav6b.src = "gfx/nav_8b.jpg";
nav7a.src = "gfx/nav_7a.jpg"; nav7b.src = "gfx/nav_7b.jpg";

}

function chgImg(imgField,newImg) {
	if (document.images) {
		document[imgField].src= eval(newImg + ".src")
	}
}