Custom profile field problem: checkboxs are not recognized

[burzum]

I've modded some custom textfields in my SMF 1.1.RC2 board following this tutorial http://www.unknownbrackets.com/tutorials/custom-profile [nofollow]

The Problem is now, that the script doesnt recognize a change of the checkbox. If checked it should insert/update the value to 1, if unchecked it should update/insert the value to 0.

Koodi [Valitse] Laajenna

                            </tr><tr>
                                <td><strong>Bogenschütze: DEBUGVALUE: ',$context['member']['options']['ffc_archer'],'</strong></td>
                                <td><input type="checkbox" name="default_options[ffc_archer]" value="1"', @$context['member']['options']['ffc_archer'] == 1 ? ' checked="checked"' : '', ' class="check" /></td>

Displaying the box as checked/unchecked works with this code. But why doesnt recognizes the script a change of the value?