I was getting the following error using the patch:
"UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 238: ordinal not in range(128)"
  So I replaced the following line:
    contents = contents.replace(u'<!–[if IE]><![endif]–>', '')
With:
    contents = contents.replace('<!–[if IE]><![endif]–>', '')

Apparently, last.fm made a subtle change to their pages that prevents BeautifulSoup from parsing the scrobbles correctly.

librefm/trunk/lastscrape$ ./lastscrape.py encukou lastfm_dump.txt
Traceback (most recent call last):
  File "./lastscrape.py", line 98, in <module>
    sys.exit(main(*sys.argv))
  File "./lastscrape.py", line 89, in main
    for artist, track, timestamp in fetch_tracks(args[1]):
  File "./lastscrape.py", line 75, in fetch_tracks
    for artist, track, timestamp in tracks:
  File "./lastscrape.py", line 34, in parse_page
    for row in soup.find('table', 'candyStriped tracklist').findAll('tr'):
AttributeError: 'NoneType' object has no attribute 'findAll'

(on a side note, BeautifulSoup 3.2 has been out for some while; it might make sense to tell users to use that instead of the 3.0.7a if it's made to work)