unity-2d-panel crashed with SIGSEGV in QConfSchema::findKey()

Oneiric i386
crash after password validation into lightdm-gtk-greeter

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: unity-2d-panel 4.2.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.0.0-9.14-generic-pae 3.0.3
Uname: Linux 3.0.0-9-generic-pae i686
NonfreeKernelModules: nvidia
Architecture: i386
Date: Sat Aug 27 19:29:34 2011
ExecutablePath: /usr/bin/unity-2d-panel
ProcCmdline: unity-2d-panel
ProcEnviron:
 PATH=(custom, no user)
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0xb6a6f937 <_ZNK11QConfSchema7findKeyEPKc+39>: mov 0x8(%eax),%edx
 PC (0xb6a6f937) ok
 source "0x8(%eax)" (0xffff95c0) not located in a known VMA region (needed readable region)!
 destination "%edx" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: unity-2d
StacktraceTop:
 QConfSchema::findKey(char const*) const () from /usr/lib/libdconf-qt.so.0
 QConf::notify(char const*) () from /usr/lib/libdconf-qt.so.0
 ?? () from /usr/lib/libdconf-qt.so.0
 ?? () from /usr/lib/libdconf-dbus-1.so.0
 ?? () from /lib/i386-linux-gnu/libdbus-1.so.3
Title: unity-2d-panel crashed with SIGSEGV in QConfSchema::findKey()
UpgradeStatus: No upgrade log present (probably fresh install)
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