Crash when comitting with non-English description

I was comitting changes to a project branch and told bazaar to load the revision's description from a file with the '-F' argument. The file contains Unicode text with some non-English characters and bazaar crashed, giving the following traceback:

(bazaar on Mac OS X 10.4 Tiger, installed using MacPorts)

bzr: ERROR: exceptions.UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 14: ordinal not in range(128)

Traceback (most recent call last):
  File "/opt/local/lib/python2.5/site-packages/bzrlib/commands.py", line 802, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/commands.py", line 758, in run_bzr
    ret = run(*run_argv)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/commands.py", line 492, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/builtins.py", line 2334, in run
    author=author)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/decorators.py", line 165, in write_locked
    return unbound(self, *args, **kwargs)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/workingtree_4.py", line 245, in commit
    result = WorkingTree3.commit(self, message, revprops, *args, **kwargs)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/decorators.py", line 165, in write_locked
    return unbound(self, *args, **kwargs)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/mutabletree.py", line 187, in commit
    revprops=revprops, *args, **kwargs)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/commit.py", line 367, in commit
    message = message_callback(self)
  File "/opt/local/lib/python2.5/site-packages/bzrlib/builtins.py", line 2324, in get_message
    bzrlib.user_encoding).read()
  File "/opt/local/lib/python2.5/codecs.py", line 618, in read
    return self.reader.read(size)
  File "/opt/local/lib/python2.5/codecs.py", line 424, in read
    newchars, decodedbytes = self.decode(data, self.errors)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 14: ordinal not in range(128)

bzr 1.0.0 on python 2.5.1.final.0 (darwin)
arguments: ['/opt/local/bin/bzr', 'commit', '-F', 'cambios.txt']
encoding: 'US-ASCII', fsenc: 'utf-8', lang: None
plugins:
  bzrtools /opt/local/lib/python2.5/site-packages/bzrlib/plugins/bzrtools [1.0.0]
  launchpad /opt/local/lib/python2.5/site-packages/bzrlib/plugins/launchpad [unknown]
  multiparent /opt/local/lib/python2.5/site-packages/bzrlib/plugins/multiparent.pyc [unknown]
*** Bazaar has encountered an internal error.
    Please report a bug at https://bugs.launchpad.net/bzr/+filebug
    including this traceback, and a description of what you
    were doing when the error occurred.