I have the following jsbin. Editing a user allows to change several things:

But clicking on the active checkbox has no effect. The name is properly updated, though.
This is the relevant part of the template:
<div class="control-group">
<label class="control-label" for="name-id">Name</label>
<div class="controls">
{{view Ember.TextField valueBinding="name" id="name-id" required="true"}}
<i class="help-block">User's name</i>
</div>
</div>
<div class="control-group">
<label class="control-label" for="active-id">Active</label>
<div class="controls">
{{view Ember.Checkbox valueBinding="active"}}
<i class="help-block">Is this user active?</i>
</div>
</div>
What is the problem with the checkbox? Why is it not being updated in the backend (FIXTURES in this case)?