System reported a bug while Viewing "firefox browser"

mozilla firefox 3 beta 5

ProblemType: Crash
Architecture: amd64
Date: Mon Apr 7 13:31:46 2008
DistroRelease: Ubuntu 8.04
ExecutablePath: /usr/lib/nspluginwrapper/i386/linux/npviewer.bin
NonfreeKernelModules: nvidia
Package: nspluginwrapper 0.9.91.5-2ubuntu1
PackageArchitecture: amd64
ProcCmdline: /usr/lib/nspluginwrapper/i386/linux/npviewer.bin --plugin /usr/lib/flashplugin-nonfree/libflashplayer.so --connection /org/wrapper/NSPlugins/libflashplayer.so/7515-3
ProcEnviron:
 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
 LANG=en_CA.UTF-8
 SHELL=/bin/bash
Signal: 11
SourcePackage: nspluginwrapper
StacktraceTop:
 g_type_check_instance_cast ()
 ?? () from /usr/lib/flashplugin-nonfree/libflashplayer.so
 ?? () from /usr/lib/flashplugin-nonfree/libflashplayer.so
 ?? () from /usr/lib/flashplugin-nonfree/libflashplayer.so
 ?? () from /usr/lib/flashplugin-nonfree/libflashplayer.so
Title: npviewer.bin crashed with SIGSEGV in g_type_check_instance_cast()
Uname: Linux 2.6.24-15-generic x86_64
UserGroups: adm admin audio cdrom dialout dip floppy fuse lpadmin plugdev video