var isnn,isie
if(navigator.appName=='Microsoft Internet Explorer') {  isie=true }
if(navigator.appName=='Netscape'){  isnn=true }
function right(e)
{
	if (isnn && (e.which == 3 || e.which == 2 ))
		return false;
	else if (isie && (event.button == 2 || event.button == 3)) 
	{
		alert("Sorry, no right click allowed.");
		return false;
	}
		return true;
}
function key(k)   
{
	if(isie) {
		if(event.keyCode==17 || event.keyCode==18 || event.keyCode==93) {
			alert("Sorry, you may not use this key.") 
			return false;
		 } 
	}
	if(isnn){
		alert("Sorry, you may not use this key.") 		
		return false; }   
}
if (document.layers) window.captureEvents(Event.KEYPRESS);  
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
if (document.layers) window.captureEvents(Event.MOUSEUP);
document.onkeydown=key;  
document.onmousedown=right;
document.onmouseup=right;
window.document.layers=right;