codice:
<style type="text/css">
#mappa {
    width: 600px;
    height: 600px;
    
    
    border-radius: 30em;
    -moz-border-radius: 30em;
    -webkit-border-radius: 30em;
    
}
    
    </style>

    <!--[if IE]> 
    <script type="text/javascript" src="curvycorners.js"></script>
    <script type="text/javascript">
    
      addEvent(window, 'load', initCorners);
    
      function initCorners() {
        var settings = {
          tl: { radius: 30 },
          tr: { radius: 30 },
          bl: { radius: 30 },
          br: { radius: 30 },
          antiAlias: true
        }
    
        curvyCorners(settings, "#mappa");
      }    
    
    </script>
    <![endif]-->