if (document.images) 					// aktive Bilder
{
img1on = new Image();
	img1on.src = "nav_but/a1.gif";
	img1off = new Image();
	img1off.src = "nav_but/b1.gif";

img2on = new Image();
	img2on.src = "nav_but/a2.gif";
	img2off = new Image();
	img2off.src = "nav_but/b2.gif";

img3on = new Image();
	img3on.src = "nav_but/a3.gif";
	img3off = new Image();
	img3off.src = "nav_but/b3.gif";

img4on = new Image();
	img4on.src = "nav_but/a4.gif";
	img4off = new Image();
	img4off.src = "nav_but/b4.gif";

img5on = new Image();
	img5on.src = "nav_but/a5.gif";
	img5off = new Image();
	img5off.src = "nav_but/b5.gif";

img6on = new Image();
	img6on.src = "nav_but/a6.gif";
	img6off = new Image();
	img6off.src = "nav_but/b6.gif";

img7on = new Image();
	img7on.src = "nav_but/a7.gif";
	img7off = new Image();
	img7off.src = "nav_but/b7.gif";

img8on = new Image();
	img8on.src = "nav_but/a8.gif";
	img8off = new Image();
	img8off.src = "nav_but/b8.gif";

;
}
// Funktion fuer Bilderaktivierung
function imgOn(imgName) {
	if (document.images) {
		document[imgName].src = eval(imgName + "on.src");
	}
}
// Funktion fuer Bilderdeaktivierung
function imgOff(imgName) {
	if (document.images) {
		document[imgName].src = eval(imgName + "off.src");
	}
}