function DisableOnContextMenu(ev) {
	return	false;
}

function DisableContextMenu(ev) {
	if (ev) {
		if (ev.button && ev.button == 2) {			// W3C DOM2
			return	false;
		} else if (!ev.button && ev.which == 3) {	// N4
			return	false;
		} else if (navigator.platform.indexOf("Mac")!=-1
					&& navigator.appName == "Netscape") {
			return	false;
		}
	} else {
		if (event && event.button && event.button == 2) {  // IE
			return	false;
		}
	}
}

if (navigator.appName == "Netscape" && !(navigator.platform.indexOf("Mac")!=-1)) {
 	document.captureEvents(Event.MOUSEDOWN);
}

document.onmousedown=DisableContextMenu;
document.oncontextmenu=DisableOnContextMenu;