Ah. Yes, there's a little 'compartment' where I put in a rinsing fluid. 'Shine-rinse' (= 1:1 translation).. and probably quite nasty chemical shite it is.
Well, may I conclude, you use the vinegar instead of 'shine-rinse' and it does the trick just as well. Mmmm, think I'm going to try it as soon as I need to refill the stuff. (thanks for the advice)