Superkaramba applets don't show up in widget browser

I created a .skz file and I installed it via “Install Widget from
local file” > “SuperKaramba”. Installation seems
correct,
.skz file is created in .kde4/share/apps/plasma/plasmoids/sk_themename and
relevant .desktop file is
in /.kde4/share/kde4/services.
plasmapkg -l lists it as sk_themename and plasmoidviewer loads the applet.
But still the plasmoid does’nt appear in the widget browser after runnin
kbuildsycoca4.
How can I add it to the desktop? I remember that superkaramba was listed under
‘categories’ in the widget browser but from some time it’s gone.
(KDE 4.2.90 (KDE 4.3 Beta2), openSUSE 11.1 64)