Unicode error in Trac wiki formatter

$ python setup.py test -m tests

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ERROR: Test Product link SHREF_TARGET_FIRST
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Traceback (most recent call last):
  File "/path/to/bloodhound/trac/trac/wiki/tests/formatter.py", line 181, in test
    v = unicode(formatter.generate(**self.generate_opts))
  File "/path/to/bloodhound/trac/trac/wiki/formatter.py", line 1501, in generate
    escape_newlines)
  File "/path/to/bloodhound/trac/trac/wiki/formatter.py", line 1283, in format
    result = re.sub(self.wikiparser.rules, self.replace, line)
  File "/path/to/venv/lib/python2.6/re.py", line 151, in sub
    return _compile(pattern, 0).sub(repl, string, count)
  File "/path/to/bloodhound/trac/trac/wiki/formatter.py", line 1201, in replace
    replacement = self.handle_match(fullmatch)
  File "/path/to/bloodhound/trac/trac/wiki/formatter.py", line 1197, in handle_match
    return internal_handler(match, fullmatch)
  File "/path/to/bloodhound/trac/trac/wiki/formatter.py", line 584, in _shref_formatter
    return self._make_link(ns, target, match, match, fullmatch)
  File "/path/to/bloodhound/trac/trac/wiki/formatter.py", line 634, in _make_link
    return resolver(self, ns, target, escape(label, False),
  File "/usr/local/lib/python2.6/dist-packages/Genshi-0.6-py2.6.egg/genshi/core.py", line 517, in escape
    return cls(text)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 8: ordinal not in range(128)

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