It turns out that fixing this bug is not trivial; it is merely one of a whole host of problems that are caused because apparently swig has changed its interface in a variety of ways. Adapting to the changes seems easy on the assumption that you understand swig, but I don't.
Perhaps version 2.0.1 (see bug 173384) solves the problems. Since version 2.1 is not free at all, perhaps the best thing to do is to drop roleplaying from Debian entirely. Thomas