upgrade from 0.32 to 0.33 makes forms fail

Bug reported in the mailing list:

http://groups.google.com/group/webpy/browse_thread/thread/3d505d3efee41833

The following example used to work in 0.32, but fails in 0.33.

>>> import web
>>> f = web.form.Form(web.form.Checkbox('A', value=False), web.form.Checkbox('B', value=True))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Library/Python/2.5/site-packages/web.py-0.33-py2.5.egg/web/form.py", line 284, in __init__
    Input.__init__(self, name, *validators, **attrs)
  File "/Library/Python/2.5/site-packages/web.py-0.33-py2.5.egg/web/form.py", line 124, in __init__
    self.id = attrs.setdefault('id', self.get_default_id())
  File "/Library/Python/2.5/site-packages/web.py-0.33-py2.5.egg/web/form.py", line 288, in get_default_id
    return self.name + '_' + value.replace(' ', '_')
AttributeError: 'bool' object has no attribute 'replace'

And another one:

With 0.33 addatts() does not produce a leading space anymore.