unity-2d-launcher crashed with SIGSEGV

[David .]

unity 2D bar has disappeared last a few seconds.

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: unity-2d-launcher 4.2.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.0.0-9.14-generic 3.0.3
Uname: Linux 3.0.0-9-generic x86_64
Architecture: amd64
CrashCounter: 1
Date: Sun Aug 28 15:22:40 2011
Disassembly: => 0x60: Cannot access memory at address 0x60
ExecutablePath: /usr/bin/unity-2d-launcher
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007.1)
ProcCmdline: unity-2d-launcher
ProcEnviron:
 LANGUAGE=fr:en
 PATH=(custom, no user)
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x60: Cannot access memory at address 0x60
 PC (0x00000060) not located in a known VMA region (needed executable region)!
SegvReason: executing NULL VMA
Signal: 11
SourcePackage: unity-2d
StacktraceTop:
 ?? ()
 ?? () from /usr/lib/x86_64-linux-gnu/libQtDeclarative.so.4
 ?? () from /usr/lib/x86_64-linux-gnu/libQtDeclarative.so.4
 ?? () from /usr/lib/x86_64-linux-gnu/libQtDeclarative.so.4
 ?? () from /usr/lib/x86_64-linux-gnu/libQtScript.so.4
Title: unity-2d-launcher crashed with SIGSEGV
UpgradeStatus: Upgraded to oneiric on 2011-08-28 (0 days ago)
UserGroups: adm admin audio cdrom dialout dip fax floppy fuse lpadmin netdev nopasswdlogin plugdev sambashare tape vboxusers video

[Apport retracing service (apport)]

StacktraceTop:
 ?? ()
 QDeclarativePropertyCache::property (engine=<optimized out>, obj=0x3241d30, name=@0x7fff99fd5818, local=...) at qml/qdeclarativepropertycache.cpp:408
 QDeclarativeObjectScriptClass::queryProperty (this=0x24117c0, obj=<optimized out>, name=@0x7fff99fd5818, flags=<optimized out>, evalContext=0x0, hints=...) at qml/qdeclarativeobjectscriptclass.cpp:167
 QDeclarativeObjectScriptClass::queryProperty (this=0x24117c0, object=<optimized out>, name=@0x7fff99fd5818, flags=<optimized out>) at qml/qdeclarativeobjectscriptclass.cpp:147
 QScript::DeclarativeObjectDelegate::getOwnPropertySlot (this=0x30fb350, object=0x7fcc04f26400, exec=0x7fcc141de048, propertyName=..., slot=...) at bridge/qscriptdeclarativeobject.cpp:74