browser_name = navigator.appName;
browser_version = parseFloat(navigator.appVersion);
if (browser_name == "Netscape" && browser_version >= 3.0) {
roll = 'true';
} else if (browser_name == "Microsoft Internet Explorer" && browser_version >= 4.0) {
roll = 'true';
} else {
roll = 'false';
}
function swapImg(img,ref)
{
if (roll == 'true' && document.images[img]) {
document.images[img].src = ref;
}
}