Application that crashed: kcmshell4
Version of the application: 
KDE Version: 4.2.95 (KDE 4.2.95 (KDE 4.3 RC1))
Qt Version: 4.5.0
Operating System: Linux 2.6.30-9-generic i686
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
I tried it several times after and it worked fine then. Maybe it was some issue that kbuildsycoca had to be run/updated for my root user first?

 -- Backtrace:
Application: KDE Control Module (kcmshell4), signal: Segmentation fault
[KCrash Handler]
#6  QDataStream::operator>> (this=0x0, i=@0xbfa124e8) at io/qdatastream.cpp:656
#7  0x00af9b0b in KServiceFactory (this=0x8ca6c78) at /build/buildd/kde4libs-4.2.95/kdecore/services/kservicefactory.cpp:44
#8  0x00af9e1c in KServiceFactory::self () at /build/buildd/kde4libs-4.2.95/kdecore/sycoca/ksycocafactory.h:200
#9  0x00aefbff in KService::serviceByMenuId (_name=@0xbfa125f8) at /build/buildd/kde4libs-4.2.95/kdecore/services/kservice.cpp:600
#10 0x00af636f in KService::serviceByStorageId (_storageId=@0xbfa125f8) at /build/buildd/kde4libs-4.2.95/kdecore/services/kservice.cpp:605
#11 0x00c7f1cf in locateModule (module=@0xbfa127c0) at /build/buildd/kdebase-runtime-4.2.95/kcmshell/main.cpp:73
#12 0x00c80783 in kdemain (_argc=2, _argv=0xbfa12ab4) at /build/buildd/kdebase-runtime-4.2.95/kcmshell/main.cpp:224
#13 0x08048642 in main (argc=2147483643, argv=0x4b7170) at /build/buildd/kdebase-runtime-4.2.95/obj-i486-linux-gnu/kcmshell/kcmshell4_dummy.cpp:3

Reported using DrKonqi