Unicode/ASCII error

After one commit, cron start to send this error message, the last line is IMO important:

usr/lib/python2.5/site-packages/creoleparser/dialects.py:381: UserWarning:
Use of Creole10 is depreciated, use create_dialect() instead.

  """
Traceback (most recent call last):
  File "./bzr_email_notifier.py", line 371, in <module>
    main()
  File "./bzr_email_notifier.py", line 105, in main
    send_commit_emails_for_branch(branch, relative_path, last_emailed_revisions)
  File "./bzr_email_notifier.py", line 216, in send_commit_emails_for_branch
    message = compose_commit_email(branch, revid, relative_path)
  File "./bzr_email_notifier.py", line 293, in compose_commit_email
    msg = config.commit_email_config.compose_email(template_data)
  File "/var/bazaar/tools/bzr-email-notifier-1.5/configuration.py", line 192, in compose_email
    body = unicode(self._body_template(actual_data))
  File "/var/lib/python-support/python2.5/Cheetah/Template.py", line 981, in __str__
    def __str__(self): return getattr(self, mainMethName)()
  File "templates_loggerhead_commit_message_html.py", line 279, in respond
  File "/var/lib/python-support/python2.5/Cheetah/DummyTransaction.py", line 31, in getvalue
    return ''.join(outputChunks)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc4 in position 8: ordinal not in range(128)