function clickIE() {
	if (document.all){
		return false;
	}
}
 
function clickNS(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=clickNS;
} else {
	document.onmouseup=clickNS;document.oncontextmenu  =clickIE;
} 
document.oncontextmenu=new Function("return false");