no defaults in form

app/admin/bans.rb

@@ -23,7 +23,7 @@ ActiveAdmin.register Ban do
       f.input :reason
       f.input :valid_from, :as => :datetime_picker
       f.input :valid_to, :as => :datetime_picker
-      f.input :activate, :input_html => { :checked => 'checked' }
+      f.input :activate
     end
     f.buttons
   end

app/admin/frequencies.rb

@@ -9,7 +9,7 @@ ActiveAdmin.register Frequency do
       f.input :helpmsg
       f.input :description
       f.input :delay
-      f.input :activate, :input_html => { :checked => 'checked' }
+      f.input :activate
     end
     f.buttons
   end