var ems_win=null;

function ems_testopenwins(){if (ems_win && !ems_win.closed)ems_win.close()}

function ems_ow(link,ww,wh){
ems_testopenwins();
var aw=screen.availWidth;
var ah=screen.availHeight;
if(aw<ww)ww=aw-20;
if(ah<wh)wh=ah-20;
var xw=(aw-ww)/2;
var yw=(ah-wh)/2;
ems_win=window.open(link,'_blank','location=no,toolbar=no,menubar=no,scrollbars=yes,status=no,resizable=yes,width='+ww+',height='+wh+',left='+xw+',top='+yw);
return false;
}

window.onunload=ems_testopenwins