browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);
if ((browserName == "Netscape" && browserVer >= 3) ||
    (browserName == "Microsoft Internet Explorer" && browserVer >= 4))
  version = "n3ie4";
else
  version = "noway";

opt01off = new Image();
opt01off.src = '/ian/graphics/a0.gif';
opt02off = new Image();
opt02off.src = '/ian/graphics/b0.gif';
opt03off = new Image();
opt03off.src = '/ian/graphics/c0.gif';
opt04off = new Image();
opt04off.src = '/ian/graphics/d0.gif';
opt05off = new Image();
opt05off.src = '/ian/graphics/e0.gif';
opt06off = new Image();
opt06off.src = '/ian/graphics/f0.gif';

if (version == "n3ie4") {
  opt01on = new Image();
  opt01on.src = '/ian/graphics/a1.gif';
  opt02on = new Image();
  opt02on.src = '/ian/graphics/b1.gif';
  opt03on = new Image();
  opt03on.src = '/ian/graphics/c1.gif';
  opt04on = new Image();
  opt04on.src = '/ian/graphics/d1.gif';
  opt05on = new Image();
  opt05on.src = '/ian/graphics/e1.gif';
  opt06on = new Image();
  opt06on.src = '/ian/graphics/f1.gif';
}

function img_act(imgNo) {
  if (version == "n3ie4")
    document.images[imgNo].src = eval (imgNo + 'on.src');
}
function img_inact(imgNo) {
  if (version == "n3ie4")
    document.images[imgNo].src = eval (imgNo + 'off.src');
}