In: R. Bergmann; G. Lindemann; S. Kim; et al. (Hrsg.). MATES. German Conference on Multiagent System Technologies (MATES-2008), 6th German Conference, located at 31st German Conference on Artificial Intelligence (KI 2008), September 23-26, Kaiserslautern, Germany, Pages 135-146, Lecture Notes in Computer Science (LNCS), Vol. 5244, ISBN 978-3-540-87804-9, Springer, 2008.