function clickIE4(){
    if (event.button==2){
	return false;
    }
}

function clickNS4(e) {

    if (document.layers||document.getElementById&&!document.all){
	if (e.which==2||e.which==3) {
	    return false;
	}
    }
}

if (document.layers) {
    document.captureEvents(Event.MOUSEDOWN);
    document.onmousedown=clickNS4;
} else if (document.all&&!document.getElementById) {
    document.onmousedown=clickIE4;
}
document.oncontextmenu=new Function("return false");