Java SE (Java Platform, Standard Edition)

If you go to the link : http://java.sun.com/docs/books/tutorial/deployment/applet/getStarted.html,
the "hello world applets" should be displayed well.

However, if you scroll the page down to make the applets invisible in the web page, and then scroll back to make the applets visible again. The applets looks kind of messy! If you refresh the web page, it looks find again.

Why this happen? How can i resove it without refreshing the web page?

I tried it on Linux and Mac, both look well. So i guess it's a problem of Windows.

Thanks!