bzr crashed with ValueError in _get_parent_index(): '<email address hidden>' is not in list

bzr branch ubuntu:facter
cd facter
bzr merge lp:~gandelman-a/ubuntu/precise/facter/merge922788

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: bzr 2.5.0~beta5-3ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-12.20-generic 3.2.2
Uname: Linux 3.2.0-12-generic x86_64
ApportVersion: 1.91-0ubuntu1
Architecture: amd64
BzrDebugFlags: set()
BzrVersion: 2.5b5
CheckboxSubmission: 2f383a1679e8525d7196eb2518a1921f
CheckboxSystem: bb422ca46d02494cdbc459927a98bc2f
CommandLine: ['/usr/bin/bzr', 'merge', 'lp:~gandelman-a/ubuntu/precise/facter/merge922788']
CrashDb: bzr
Date: Mon Jan 30 12:58:13 2012
ExecutablePath: /usr/bin/bzr
FileSystemEncoding: UTF-8
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Alpha amd64 (20110817)
InterpreterPath: /usr/bin/python2.7
Locale: de_DE.UTF-8
PackageArchitecture: all
Platform: Linux-3.2.0-12-generic-x86_64-with-Ubuntu-12.04-precise
ProcCmdline: /usr/bin/python /usr/bin/bzr merge lp:~gandelman-a/ubuntu/precise/facter/merge922788
PythonVersion: 2.7.2
SourcePackage: bzr
Title: bzr crashed with ValueError in _get_parent_index(): '<email address hidden>' is not in list
UpgradeStatus: Upgraded to precise on 2012-01-12 (17 days ago)
UserEncoding: utf-8
UserGroups: adm admin audio cdrom dialout lpadmin plugdev sambashare