function openwin(winwidth,winheight,wintitle,winurl){
	// this will position the popup window to the center of the screen
	var winl = (screen.width - winwidth) / 2;
	var wint = (screen.height - winheight) / 2;
	window.open(winurl, wintitle, 'width='+winwidth+',height='+(winheight-50)+',top='+wint+',left='+winl+',location=no,scrollbars=no,menubars=no,toolbars=no,resizable=no,status=no');
}