ValueError: unsupported format character 'j' (0x6a) at index 19

ubuntuone-preferences hangs after start.
It seems to be a localisation issue since it disappears when setting LANG to en_US (I have Esperanto by default).

==========
$ echo $LANG
eo.utf8

$ ubuntuone-preferences
Exception in thread Thread-2:
Traceback (most recent call last):
  File "/usr/lib/python2.6/threading.py", line 532, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.6/threading.py", line 484, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/bin/ubuntuone-preferences", line 162, in do_rest_request
    callback(result)
  File "/usr/bin/ubuntuone-preferences", line 681, in got_quota_info
    self.update_quota_display(used, total)
  File "/usr/bin/ubuntuone-preferences", line 635, in update_quota_display
    'percent' : percent })
ValueError: unsupported format character 'j' (0x6a) at index 19

Terminated
$ LANG=en_US ubuntuone-preferences

(process:14800): Gtk-WARNING **: Locale not supported by C library.
        Using the fallback 'C' locale.

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 10.04.3 LTS
Release: 10.04
Codename: lucid

$ uname -a
Linux my-desktop 2.6.32-33-generic #72-Ubuntu SMP Fri Jul 29 21:07:13 UTC 2011 x86_64 GNU/Linux

$ dpkg -l ubuntuone-preferences
Neniu pako kongruanta al ubuntuone-preferences.

$ dpkg -l ubuntuone*
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Cfg-files/Unpacked/Failed-cfg/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Nomo Versio Priskribo
+++-=====================================================-=====================================================-==========================================================================================================================
ii ubuntuone-client 1.2.2-0ubuntu2 Ubuntu One client
ii ubuntuone-client-gnome 1.2.2-0ubuntu2 Ubuntu One client GNOME integration
ii ubuntuone-client-tools 1.2.2-0ubuntu2 Ubuntu One client tools
un ubuntuone-oauth-login <nenio> (neniu priskribo disponeblas)
un ubuntuone-storage-protocol <nenio> (neniu priskribo disponeblas)
un ubuntuone-storagefs <nenio> (neniu priskribo disponeblas)

$ python --version
Python 2.6.5

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