Distinguishable multiple SubmitButtons in the buttons attribute of a form

[moschlar]

I need to have multiple SubmitButtons that I need to distinguish on the server side! If they have a name attribute, their values get send in the POST request. But validation strips their values from the resulting dictionary.
Since I would like to use TurboGears @validate decorator, I would like to have some kind of trick to include the buttons in the validated data!

To reproduce the behaviour, consider the following form definition:

import tw2.core as twc
import tw2.forms as twf
import tw2.dynforms as twdf

class JudgementForm(twdf.CustomisedTableForm):

    title = 'Judgement'

    assignment_id = twf.HiddenField()
    submission_id = twf.HiddenField()

    class annotations(twdf.GrowingGridLayout):
        line = twf.TextField(size=3, validator=twc.IntValidator, css_class='span1')
        comment = twf.TextField(size=65, css_class='span4')
    comment = twf.TextArea(placeholder=u'Comment on the above source code', css_class='span5', rows=8)
    corrected_source = twf.TextArea(placeholder=u'Correct the above source code', css_class='span5', rows=8)

    buttons = [
        twf.SubmitButton('submit', name='submit', value='Submit', css_class='btn btn-primary'),
        twf.SubmitButton('reset', name='reset', value='Delete', css_class='btn btn-danger')]

If I just try it in a IPython shell, I just get:

In [4]: JudgementForm().validate({})
Out[4]: 
{'annotations': [],
 'assignment_id': '',
 'comment': '',
 'corrected_source': '',
 'submission_id': ''}

In [5]: JudgementForm().validate({'submit':'Submit'})
Out[5]: 
{'annotations': [],
 'assignment_id': '',
 'comment': '',
 'corrected_source': '',
 'submission_id': ''}

where I would like to have at least the name of the pressed button included.

Is there any way to achieve that?