was ist das denn für ein script

<script language="JavaScript">
<!--
var SymRealOnLoad;
var SymRealOnUnload;

function SymOnUnload()
{
  window.open = SymWinOpen;
  if(SymRealOnUnload != null)
     SymRealOnUnload();
}

function SymOnLoad()
{
  if(SymRealOnLoad != null)
     SymRealOnLoad();
  window.open = SymRealWinOpen;
  SymRealOnUnload = window.onunload;
  window.onunload = SymOnUnload;
}

SymRealOnLoad = window.onload;
window.onload = SymOnLoad;

//-->
</script>