function popup(html) {

	ns4 = (document.layers)? true:false
	ie4 = (document.all)? true:false
	var width = (ns4)? window.innerWidth/2 : document.body.offsetWidth/2

	document.getElementById('popup').innerHTML = html;
	document.getElementById('popup').style.left = (width-337.5);
	if (document.getElementById) {
		// this is the way the standards work
		var style2 = document.getElementById('popup').style;
		style2.display = style2.display? "":"block";
	}
	else if (document.all) {
		// this is the way old msie versions work
		var style2 = document.all['popup'].style;
		style2.display = style2.display? "":"block";
	} 
	else if (document.layers) {
		// this is the way nn4 works
		var style2 = document.layers['popup'].style;
		style2.display = style2.display? "":"block";
	}
	
	new Effect.Appear('popup');
}