Visits by server time widget: hours missing


I just updated from piwik 1.7.1 to 1.8.2 and have a problem with the visits by server time widget:
when the widget is loaded the first time (for example by visiting my piwik or opening the dashboard), it only shows values from 0 - 9h. (it is now 21.00). Only when I make changes to the widget (by selecting another graph type like pie chart or selecting to show visits and actions), the widget shows all values from 0 - 21h. But this is not saved. If I leave my piwik and then open it again, there again are only values from 0 - 9h shown in the visits by server time widget.

Any idea what the problem is?

I think I solved the problem:
I simply deleted the old widget from the dashboard and added a new widget “visits by server time”. Now it works correctly again.

I can confirm that removing and re-adding the widget solves the problem.
Thanks for the hint.