Uncommit error invites to retry the uncommit which will lead to another uncommit

Use case described in the attached doc file.

* OS: WIN7-64

* bzr details:

About Tortoise Bazaar
Tortoise Bazaar 0.6.6
Executable: C:\Program Files (x86)\Bazaar\tbzrcommand.exe
Library: C:\Program Files (x86)\Bazaar\lib\library.zip\tbzrlib
Copyright 2008-2012 Canonical Ltd.
About Bazaar
Bazaar (bzr) 2.6.0
  Python interpreter: C:\Program Files (x86)\Bazaar\python27.dll 2.7.6
  Python standard library: C:\Program Files (x86)\Bazaar\lib\library.zip
  Platform: Windows-7-6.1.7601-SP1
  bzrlib: C:\Program Files (x86)\Bazaar\lib\library.zip\bzrlib
  Bazaar configuration: C:/Users/aleroyer/AppData/Roaming/bazaar/2.0
  Bazaar log file: C:\Users\aleroyer\Documents\.bzr.log

Copyright 2005-2012 Canonical Ltd.
http://bazaar.canonical.com/

bzr comes with ABSOLUTELY NO WARRANTY. bzr is free software, and
you may use, modify and redistribute it under the terms of the GNU
General Public License version 2 or later.

Bazaar is part of the GNU Project to produce a free operating system.

About Plugins
bzrtools 2.6.0
Various useful commands for working with bzr.
changelog_merge 2.6.0
Merge hook for GNU-format ChangeLog files
colo 0.4.0
Work with colocated branches using current technology.
explorer 1.3.0
Version Control for Human Beings.
fastimport 0.14.0dev
FastImport Plugin
git 0.6.12
A GIT branch and repository format implementation for bzr.
launchpad 2.6.0
Launchpad.net integration plugin for Bazaar.
loom 2.3.0dev
(no description)
netrc_credential_store 2.6.0
Use ~/.netrc as a credential store for authentication.conf.
news_merge 2.6.0
Merge hook for bzr's NEWS file.
pipeline 1.5.0
Manage a series of branches as a pipeline.
qbzr 0.23.1
QBzr - Qt-based frontend for Bazaar
rewrite 0.6.4dev
Rebase support.
svn 1.2.3
Support for Subversion branches
upload 1.2.0dev
Upload a working tree, incrementally.
xmloutput 0.8.9
This plugin adds an option (--xml) to log and provides an xml version of some builtin commands.