Back from the marathon. I had a very fast race. Here are the results. The final time was 1:40:07 which is around 5 minutes better than expected. My buddy Ulf was actually 1m18s faster than me. Congratulations.
Unfortunately, the GPS phone did not have enough power to send messages for 100 minutes so it stopped sending after an hour. So my marathon page does not reflect the whole track. But I had another GPS receiver with me that hopefully recorded the whole route. I am going to update the marathon page when I am recovered.
Thanks to Tobias, Jörg for setting up the system. Many thanks also to Papillon who was my pacemaker in the recent weeks. Thanks also to the team of berliner-stadtplan.com for allowing me to use their maps.