Wine tasting event at the Altes Rathaus - Munich

There is an annual wine tasting event in the basement of the Altes Rathaus today and tomorrow, I think from 12 until 7. It costs 5 Euros and you can taste as many different wines as many times as you wish. If you then buy one (or more) of the wines you like, you get the 5 Euros back in form of reduction of your spend, if you spend over 35 Euros.
I cant find any information about this online, but was informed by a friend of this event, (we were there last year), and Im off to try a few today.

Ratskeller München : Frühjahrsweinprobe

Trying to do a properlink, but it wont let me. Just go to here and scroll down to April 25th