Cannot retrieve Twitter messages and responses. HTTP Error 400: Bad request

It works for Identi.ca but not for Twitter.

I am running Gwibber 0.8 on Ubuntu 9.04 Beta.

This is the debug output:
Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/gwibber/microblog/__init__.py", line 46, in get_data
    for message in method(client):
  File "/usr/lib/python2.6/dist-packages/gwibber/microblog/twitter.py", line 216, in receive
    for data in self.get_messages():
  File "/usr/lib/python2.6/dist-packages/gwibber/microblog/twitter.py", line 166, in get_messages
    urllib.urlencode({"count": self.account["receive_count"] or "20"})))
  File "/usr/lib/python2.6/dist-packages/gwibber/microblog/twitter.py", line 161, in connect
    url, data, {"Authorization": self.get_auth()})).read()
  File "/usr/lib/python2.6/urllib2.py", line 124, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib/python2.6/urllib2.py", line 389, in open
    response = meth(req, response)
  File "/usr/lib/python2.6/urllib2.py", line 502, in http_response
    'http', request, response, code, msg, hdrs)
  File "/usr/lib/python2.6/urllib2.py", line 427, in error
    return self._call_chain(*args)
  File "/usr/lib/python2.6/urllib2.py", line 361, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.6/urllib2.py", line 510, in http_error_default
    raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
HTTPError: HTTP Error 400: Bad Request