The course "Simulative Untersuchung von Protokollfunktionen des Internet" (Simulative Evaluation of Internet Protocol Functions) has been developed in 2004 at the Technical University of Berlin, Telecommunications Network Group (TKN). It uses a model framework called Protsim, which is based on OMNeT++.
This semester (WS05/06) the course is taught again at the Technical University of Berlin as well as at the Technical University of Ilmenau. Self-teaching materials and source code are available on the web pages.
For those who cannot speak German, some key to the TU Ilmeau page:
Themenliste contains exercises with detailed instructions and background information (unfortunately in German only)
Aufgabenquellen contains Protsim-based source bundles for the exercises. Indentifiers and comments in the source are in English!
Selbststudienmaterial contains an excellent set of slides (in English!) which contain C++, simulation and probability primer, intro to OMNeT++ and Protsim -- basically everything to get started.
At the TU Berlin page only the course handouts are publicly available.