It seems that HTMLParser.feed throws an exception whenever an attribute
name contains both quotation mark '&' and non-ascii characters.

Running the attached test file with Python 2.5 succeeds, but with Python
2.6, the result is:

C:\Python26>python.exe test.py
Without & in attribute
OK
With & in attribute
Traceback (most recent call last):
  File "test.py", line 18, in <module>
    HP().feed(s)
  File "C:\Python26\lib\HTMLParser.py", line 108, in feed
    self.goahead(0)
  File "C:\Python26\lib\HTMLParser.py", line 148, in goahead
    k = self.parse_starttag(i)
  File "C:\Python26\lib\HTMLParser.py", line 249, in parse_starttag
    attrvalue = self.unescape(attrvalue)
  File "C:\Python26\lib\HTMLParser.py", line 386, in unescape
    return re.sub(r"&(#?[xX]?(?:[0-9a-fA-F]+|\w{1,8}));",
replaceEntities, s)
  File "C:\Python26\lib\re.py", line 150, in sub
    return _compile(pattern, 0).sub(repl, string, count)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 0:
ordinal
not in range(128)

I am running:

Python 2.6rc2 (r26rc2:66507, Sep 18 2008, 14:27:33) [MSC v.1500 32 bit
(Intel)] on win32