Hallo Erwin, a long as the vfmg still exists (who knows?!) the Sommertagung will be at the beginning of the september each year.
Concerning 2012: i put it in the calender. the Sommertagung is open also for non-members of the vfmg. i will give you details if possible, so far i know the guys from saxonia it will be great.
tot ziens
jürgen