function popup(url) 
{
 params  = 'width='+screen.width;
 params += ', height='+screen.height;
 params += ', top=0, left=0'

 params += ', menubar=yes';
 params += ', location=yes';
 params += ', scrollbars=1';
 params += ', toolbar=yes';
 params += ', status=yes';

 newwin=window.open(url,'windowname4', params);
 if (window.focus) {newwin.focus()}
 return false;
}