Sorry I am a bit late to this thread. You don't need a streaming server for PoodLL. If you use the MP3 recorder it will just work.
Whenever you set up a PoodLL thing (assignment submission, question , atto editor icons etc) you can choose the recorder that your students will use. If you choose the mp3 recorder, it works without any streaming server.
The option to use the public PoodLL streaming server is there for you, if you choose to use the other audio recorder or the video recorder. It is usually not necessary to set up your own streaming server unless you have lots of students or are keen to keep the whole show in house.
Let me know if you have any questions. And if you want to thrash around trying it out, there is a recording quiz all set up on http://demo.poodll.com . Go crazy there.
Justin ( the PoodLL guy )