collapsible element do not take into account the attribute "data-state=collapsed" since alpha2

collapsible element do not take into account the attribute "data-state=collapsed" since alpha2

<div data-role="collapsible" data-state="collapsed">
...
</div>

are always displayed expanded.
-------------------------------------------------
alpha1 code for plugin:
...
collapsed: $(this).is('[data-state="collapsed"]'),
...
------------------------------------------------
alpha2 code for plugin:
...
collapsed: false,
...