Breaks delete button in field collection

After click on button and for some reason form was not submitted, its break delete buttons in field collection. (for example if we use custom client side validation)
What happening?
Immediately after click, hidden element is created (with button name and value), but not removed with "disabled" attribute. And think, hidden field "op" breaks ajax execution.

solution: remove garbage
in hideSubmitResetButtons() after
$(el).removeClass(Drupal.checkPlain(Drupal.settings.hide_submit.hide_submit_hide_css)).removeAttr('disabled');
add
$('input[name="'+$(el).attr('name')+'"][type="hidden"][value="'+$(el).attr('value')+'"]').remove();
and in "default" case too

// by the way, reset buttons not worked without this patch