nepomukservicestub crashed with SIGSEGV in strcmp()

[smeg0l]

Binary package hint: kdebase-runtime

i have both ubuntu and kubuntu installed when running youtube then when i tried to close firefox i got this error message

ProblemType: Crash
Architecture: i386
DistroRelease: Ubuntu 9.04
ExecutablePath: /usr/bin/nepomukservicestub
NonfreeKernelModules: nvidia
Package: kdebase-runtime 4:4.2.1-0ubuntu1 [modified: usr/lib/kde4/libexec/kdesu]
ProcCmdline: /usr/bin/nepomukservicestub nepomukstorage
ProcEnviron:
 LANG=da_DK.UTF-8
 SHELL=/bin/bash
 LANGUAGE=
Signal: 11
SourcePackage: kdebase-runtime
StacktraceTop:
 strcmp () from /lib/tls/i686/cmov/libc.so.6
 librdf_digest_register_factory () from /usr/lib/librdf.so.0
 librdf_digest_md5_constructor () from /usr/lib/librdf.so.0
 librdf_init_digest () from /usr/lib/librdf.so.0
 librdf_world_open () from /usr/lib/librdf.so.0
Title: nepomukservicestub crashed with SIGSEGV in strcmp()
Uname: Linux 2.6.28-8-generic i686
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare