var pagestatus=0;
function winpage(url,title,x,y) {
   if (pagestatus != 0) pagestatus.close();
   if (!title) title = "okno";
   var winx = (screen.width-x)/2;
   var winy = (screen.height-y)/2;
   pagestatus = window.open( url , title ,"toolbar=yes,menubar=no,location=no,directories=no,scrollbars=yes,resizable=no,status=yes,top="+winy+",left="+winx+",width="+x+",height="+y);
   return;
}