clicking on a weekday in the the weekly overview doesn't change the selected day to day that's been clicked on

Steps to reproduce:

1. login to http://beta.kolabnow.com/
2. select "calendar" in the drop-down error in the top right corner
3. select weekly calendar view on the right hand side of the monthly overview on the left
4. click on e.g. "MO 10-22"

Actual results:
nothing happens

Expected results:
the calendar changes the selected day to "MO 10-22" which you can see by the slightly differently coloured background in the weekly overview as well as in the monthly overview