speech recognition software

I have just read this article. It is a good idea to donate speech to the VoxForge project. But at the moment, I do have a different question: how is it possible to create an acoustic model (after you have donated some speech)? At the moment, there are acoustic models in the development for the English, Dutch, German and Russian language. Obviously, all (or most) of them are created with CMU Sphinx. But how do you use CMU Sphinx? This is one of the main questions I do have at the moment. It is not easy to find the answer, but I am trying. It should be possible to use Sphinx (and German or English speech files) to create an acoustic model (German or English). But how is it possible to achieve this goal? It would be helpful if there were a good documentation out there. Probably there is, but it is not easy to get involved.