function popup(url) {
	  winparams = 'scrollbars=yes, width=500, height=500, resizable=yes, status=yes';
	  if (!twindow){
		twindow = window.open('','textwin', winparams);
	}

	if (twindow.closed) {
		twindow=window.open('big/'+url,'textwin', winparams);
		twindow.focus();
	}
	else {
		twindow.location = 'big/'+url;
		twindow.focus();
	}
	twindow.resizeTo(500,500);
}
function exit() {
	if (twindow && twindow.closed == 0) { twindow.close(); }
}
twindow='';