There is incorrect html/javascript code at the end of the page of qt creator doc.
Look the source file the error is at the end of the file

</body>
</html>
[0]; s.parentNode.insertBefore(ga, s);
  })();
  </script>
</body>
</html>

The page issue are:

http://doc.qt.nokia.com/qtcreator-2.3/index.html
http://doc.qt.nokia.com/qtcreator-2.2/index.html
http://doc.qt.nokia.com/qtcreator-extending/index.html
http://doc.qt.nokia.com/qtcreator-2.1/index.html
http://doc.qt.nokia.com/qtcreator-2.0.1/index.html
http://doc.qt.nokia.com/qtcreator-2.0/index.html