IE4plus = (document.all) ? true : false;
NS4 = (document.layers) ? true : false;

function clickIE()
{
	return false;
}

function clickNS(e)
{
	if (e.which==2 || e.which==3) 
	{
		return false;
	}
}
if (!IE4plus) 
{
	document.captureEvents(Event.MOUSEDOWN || Event.MOUSEUP);
	document.onmousedown=clickNS;
	document.onmouseup= clickNS;
	document.oncontextmenu=clickIE; // For NS 6+
} 
else 
{
	document.onmouseup= clickIE;
	document.oncontextmenu=clickIE;
}