compiz crashed with SIGSEGV in g_datalist_id_set_data_full() when moving to single monitor mode

When moving from multi-monitor mode to single monitor (by unplugging the monitor), I got this crash.

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: libnux-2.0-0 2.2.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-12.21-generic 3.2.2
Uname: Linux 3.2.0-12-generic x86_64
ApportVersion: 1.91-0ubuntu1
Architecture: amd64
CrashCounter: 1
Date: Mon Feb 6 08:49:32 2012
ExecutablePath: /usr/bin/compiz
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120111)
ProcCmdline: compiz
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SegvAnalysis:
 Segfault happened at: 0x7f0ffe9b2c85 <g_datalist_id_set_data_full+341>: mov 0x0(%r13),%esi
 PC (0x7f0ffe9b2c85) ok
 source "0x0(%r13)" (0xaaaaaaaaaaaaaaa8) not located in a known VMA region (needed readable region)!
 destination "%esi" ok
SegvReason: reading unknown VMA
Signal: 11
SourcePackage: nux
StacktraceTop:
 g_datalist_id_set_data_full () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
 ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 g_object_unref () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
 unity::PanelTray::~PanelTray() () from /usr/lib/compiz/libunityshell.so
 unity::PanelTray::~PanelTray() () from /usr/lib/compiz/libunityshell.so
Title: compiz crashed with SIGSEGV in g_datalist_id_set_data_full()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo