var NewWind
function popup(url,w,h)
{
if (NewWind && !NewWind.closed) 
{
	NewWind.close()
} 

params = ""
params += "resizable=no,"
params += "scrollbars=yes,"
params += "status=no,"
params += "width=" + w + ","
params += "height=" + h


NewWind = window.open(url, "" , params);
}