using the demo tracker in 0.6.5

python demo.py

I'm not able to register a new user.
I take.

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KeyError: 'username'	Python 2.3.3
/usr/local/bin/python

A problem occurred while running a Python script. Here
is the sequence of function calls leading up to the
error, with the most recent (innermost) call first. The
exception attributes are:
      __doc__ = 'Mapping key not found.'
      __getitem__ = <bound method KeyError.__getitem__
of <exceptions.KeyError instance>>
      __init__ = <bound method KeyError.__init__ of
<exceptions.KeyError instance>>
      __module__ = 'exceptions'
      __str__ = <bound method KeyError.__str__ of
<exceptions.KeyError instance>>
      args = ('username',)

/home/gpciceri/works/roundup-0.6.5/roundup/cgi/client.py
in
registerAction(self=<_roundup_tracker_1.interfaces.Client
instance>)
  766         tracker_name = self.db.config.TRACKER_NAME
  767         subject = 'Complete your registration to
%s'%tracker_name
  768         body = '''
      body = undefined, props = {'__time':
1077608949.1061461}, tracker_name = 'Roundup issue
tracker', self = <_roundup_tracker_1.interfaces.Client
instance>, global base = undefined, otk =
'vtjEbi7seVngbIE4m4VoC4utqO19Aeg3'
  769 To complete your registration of the user
"%(name)s" with %(tracker)s,
  770 please visit the following URL:

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