bzr: ERROR: Unprintable exception

Steps to reproduce:

* Run a Swedish installation of 12.04
bzr branch lp:~ubuntu-audio-dev/pulseaudio/ubuntu.precise (I guess any other branch will do as well)
bzr bd
While "bzr bd" is running, open a second terminal in the same directory and execute "bzr commit"

You will be met by:

bzr: ERROR: Unprintable exception LockContention: dict={'msg': IOError(11, 'Resursen tillf\xc3\xa4lligt otillg\xc3\xa4nglig'), 'lock': u'/tmp/ubuntu.precise/.bzr/checkout/dirstate'}, fmt='Could not acquire lock "%(lock)s": %(msg)s', error=UnicodeDecodeError('ascii', '[Errno 11] Resursen tillf\xc3\xa4lligt otillg\xc3\xa4nglig', 25, 26, 'ordinal not in range(128)')

The LockContention is probably correct (after all, I did do two bzr commands in parallel), but it would be nice if it could print a proper error message.

ProblemType: Bug
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
Date: Thu Feb 2 16:38:22 2012
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120103)
PackageArchitecture: all
SourcePackage: bzr
UpgradeStatus: No upgrade log present (probably fresh install)