title: Excel biff5 to biff8 conversion
body: <p>My system uses Apache-POI to manage some xls files. Now I've got almost 300 xls files, but it appears that they are in an old format so i got this exception:</p>
  
  <blockquote>
    <p>The supplied spreadsheet seems to be Excel 5.0/7.0 (BIFF5) format. POI only supports BIFF8 format (from Excel versions 97/2000/XP/2003)</p>
  </blockquote>
  
  <p>Is there a way to handle that or to automatically convert all those files to a biff8 format?</p>