function lang(code)
 {var ini = top.frames.location.href;
  var url = ini.replace(/-\w\w\.htm/,"-"+code+".htm"); // -xx.htm -> -yy.htm
  url = url.replace(/-\w\w\.php/,"-"+code+".php"); // -xx.php -> -yy.php
  url = url.replace(/lang=\w\w/,"lang="+code); // lang=xx -> lang=yy
  if (url == ini)
   {if (url.indexOf("?")>0)
      url = url.replace(/\?/,"?lang="+code+"&"); // ?etc -> ?lang=yy&etc
    else if (url.indexOf("#")>0)
      url = url.replace(/#/,"?lang="+code); // #etc -> ?lang=yy
    else
      url = url+"?lang="+code; // vide -> ?lang=yy
   }
  top.frames.location.href = url;
 }