backend crashed with ValueError in loads()

[Nipas]

Binary package hint: checkbox

System: ubuntu 10.04 beta amd64, all updates installed
I was browsing the internet via firefox when suddenly backend crashed. Unfortunately I cannot ensure if this bug isn't the same as another bug i read on launchpad concerning backend in Lucid

ProblemType: Crash
DistroRelease: Ubuntu 10.04
Package: checkbox 0.9
ProcVersionSignature: Ubuntu 2.6.32-17.26-generic 2.6.32.10+drm33.1
Uname: Linux 2.6.32-17-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Mon Mar 29 11:27:29 2010
ExecutablePath: /usr/share/checkbox/backend
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Beta amd64 (20100318)
InterpreterPath: /usr/bin/python2.6
PackageArchitecture: all
ProcCmdline: /usr/bin/python /usr/share/checkbox/backend /tmp/checkboxQVr5IF/input /tmp/checkboxQVr5IF/output
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, no user)
 LANG=en_US.utf8
PythonArgs: ['/usr/share/checkbox/backend', '/tmp/checkboxQVr5IF/input', '/tmp/checkboxQVr5IF/output']
SourcePackage: checkbox
Title: backend crashed with ValueError in loads()
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