I have a folder of static html,imgs,flash content that lives outside of the webapp folder. Right now I\'m using a symbolic link to map that folder into my webapp directory.
You can override DefaultServlet with your own implementation. You can perfectly subclass it, it's a public class. Here are the functional specifications of the DefaultServlet, you need to adhere it.
On the other hand you can ignore DefaultServlet and go for your own solution, an example can be found here.