function setStartPage() {
      var b = document.body;
      var ua = navigator.userAgent;
      var ie = ua.indexOf("MSIE");
      var iever = parseInt(ua.substring(ie+5, ie+6));
      var os = ua.indexOf("Windows");
      if(ie > 0 && iever >= 5 && os > 0 && !window.opera){
         var homepage = "http://www.livedoor.com";
         var jumpto = "http://www.livedoor.com/r/set_blog/";
         b.style.behavior = "url('#default#homepage')";
         var is_home =
             b.isHomePage(homepage) || b.isHomePage(homepage + "/");
          if(is_home)
              alert("livedoor はすでにスタートページに設定されています。");
          else
              b.setHomePage(homepage + "/");
         is_home =
             b.isHomePage(homepage) || b.isHomePage(homepage + "/");
         if(is_home) {
             document.location.replace(jumpto);
         }
      }
      else {
          document.location.href="http://helpguide.livedoor.com/start.html";
      }
}