Version: 4.4 pre (using KDE 4.5.1)
apart from hiding the calendar manager from the settings menu, it can also be hidden with the mouse by dragging its handle downwards, making it difficult to figure out where the cal. manager is. at least in one case this happened to a user updating from KDE 3.5 -> 4.5.1, as stated on the kde mailing list <http://lists.kde.org/?l=kde&m=128420583720057&w=2>. in my opinion it's unecessary to have two ways to hide the cal. manager; one would be sufficient.
Steps to Reproduce:
enable calendar manager from settings menu, then hide it with the mouse by dragging its handle downward. now disable and enable from settings menu, and it won't show up until it's dragged up with the mouse again.
i would expect the cal. manager to be displayed when that option is checked in the settings menu, whether or not it's been hidden with the mouse previously.
The calendar manager now has a minimum height.