function keyDown(e) {

if (navigator.appName == 'Netscape') {
if(e.which == 17) {
alert('This action is prohibited');
e.cancelBubble = true;
return false;
}

}

// IE gives me no problem at all...
// if (navigator.appName == 'Microsoft Internet Explorer') {
// if (window.event.keyCode == 17) {
// window.event.keyCode = 0;
// alert('This action is prohibited');
// return false;
// }
// }
}

document.onkeydown = keyDown;
if (navigator.appName == 'Netscape')
document.captureEvents(Event.KEYDOWN)