Roadcasting is a novel technology that emerged from the adaptation of methods for personalized audio transmissions over the Internet ("podcasting") to the area of mobile ad-hoc networks, in particular car-tocar networks. Current approaches to roadcasting, however, concentrate on the human-to-computer interface and high level peer-to-peer file sharing systems and do not deal with the communication infrastructure in any detail. As a consequence, scalability and adaptability of these existing systems remained unexplored so far. Starting from an analysis of new applications for roadcasting and the problems involved, this paper presents a novel architecture for a cross-layer emulation environment geared especially to roadcasting scenarios, including a modular routing architecture and routing optimization methods that will allow adaptability and scalability evaluations of roadcasting solutions in the near future.