This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
Personally, I'd test the functionality outside of the servlet. I use servlets (well, not really, but their equivalent) only to marshall data to service objects (or similar). I keep functionality isolated from the Servlet spec as much as possible to make testing easier.