function centerPopUp( url, name, width, height, scrollbars ) {

	if( scrollbars == null ) scrollbars = "0"
	
		str = "";
		str += "resizable=1,";
		str += "scrollbars=" + scrollbars + ",";
		str += "width=" + width + ",";
		str += "height=" + height + ",";
		
	if ( window.screen ) {
		var ah = screen.availHeight - 30;
		var aw = screen.availWidth - 10;
		
		var xc = ( aw - width ) / 2;
		var yc = ( ah - height ) / 2;
		
		str += ",left=" + xc + ",screenX=" + xc;
		str += ",top=" + yc + ",screenY=" + yc;
	}
	window.open( url, name, str );
}