function openwindow (url, name, w, h, perc, scroll)
{
	var winX = (screen.availWidth - w)*perc*.01;
	var winY = (screen.availHeight - h)*perc*.01;
	popupWin = window.open(url, name,'width=' + w + ',height=' + h + ',left=' + winX + ',top=' + winY + ',scrollbars=' + scroll + ',toolbar=0;');
}