var win = null;
function NewWindow(mypage, w, h, scroll)
{
	if ( win != null ) win.close();
	LeftPosition = (screen.width) ? (screen.width - w)/2 : 0;
	TopPosition = (screen.height) ? (screen.height - h)/2 : 0;
	settings = 'height=' + h + ',width=' + w + ',top=' + TopPosition + ',left=' + LeftPosition + ',scrollbars=' + scroll + ',resizable';
	win = window.open(mypage, 'name', settings);
	win.focus();
	return false;
}