DTMCC05WAP-G stands for a recent (4.Qrt 2000) real-life case study dealing with the practical aspects of large scale mobile entertainment services as currently prototyped by European internet service providers. Software platforms for mobile entertainment services, e.g., interactive multi-player games or profile based personal matching using real- time geographical information, are facing a number of software-technical challenges, with respect to both, reliability as well as scaleability. In this case study report, we will provide a brief outline of the specific requirements for the WAP-G platform and, in the main part of the paper, focus on two technical key issues in the context of interactive multi-player WAP games: maintaining consistent user session and game state information in presence of unreliable WAP connections and device independent output generation and transformation for not fully standardized WML end user devices. The former issue has been dealt with by running an array of server-side Mealy-style state machines yielding a consistent game state database used for session and game recovery in presence of flapping WAP connections. The latter challenge has been met by using an XML-style intermediate output representation based on a specific WML DTD in such a way that XML output generation and translation happens as a side effect of state transitions in the above mentioned state machines. In this paper, both both problems together with real-life tested solutions are discussed in detail.