A little less than five years ago I found the following java script which I've copied and pasted into my pages ever since, to disable right-clicking when those pages are viewed using either IE or Netscape. How do I amend or replace this java script to continue to disable right-clicking by users of IE and Netscape and, at the same time, disable it by users of the new Firefox browser?

Here's the javascript:

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<SCRIPT LANGUAGE="JavaScript1.1">
<!-- Original: Martin Webb (martin@irt.org) -->

<!-- This script and many more are available free online at -->
<!-- The JavaScript Source!! http://javascript.internet.com -->

<!-- Begin
function right(e) {
if (navigator.appName == 'Netscape' or 'Mozilla Firefox' &&
(e.which == 3 || e.which == 2))
return false;
else if (navigator.appName == 'Microsoft Internet Explorer' &&
(event.button == 2 || event.button == 3)) {
alert("Please respect copyright.");
return false;

}
return true;
}

document.onmousedown=right;
document.onmouseup=right;
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
if (document.layers) window.captureEvents(Event.MOUSEUP);
window.onmousedown=right;
window.onmouseup=right;
// End -->
</script>

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