Dallmayr are doing a wine-tasting session in the old Rathaus on 18th March. There will be wines from 37 wine-makers in Germany and Austria.
There are 2 sessions: 13:00-17:00 or 19:30-22:00.
Tickets are 15 euros per person, refunded on purchase of 12 bottles.
There are ticket order forms in the shop on DienerStr, and they're also available online:
Tickets: 13:00-17:00 session
Tickets: 19:30-22:00 session
(Not sure if those links will work properly - if not just do a search for "Weinprobe")