var mymessage = "Deze site is beveiligd!";
function rtclickcheck(keyp){
	if (navigator.appName == "Netscape" && keyp.which == 3) {
		alert(mymessage);
		return false; 
	}
	if (navigator.appVersion.indexOf("MSIE") != -1 && event.button == 2) {
		alert(mymessage);
		return false; 
	}
}