diff --git a/app/controllers/todos_controller.rb b/app/controllers/todos_controller.rb
index aa629cda..776f92f9 100644
--- a/app/controllers/todos_controller.rb
+++ b/app/controllers/todos_controller.rb
@@ -423,6 +423,7 @@ class TodosController < ApplicationController
 
     @todo = current_user.todos.find(params['id'])
     @original_item = current_user.todos.build(@todo.attributes)  # create a (unsaved) copy of the original todo
+    @original_item_due_id = get_due_id_for_calendar(@original_item.due)
 
     update_tags
     update_project
@@ -442,7 +443,6 @@ class TodosController < ApplicationController
       @saved = false
     end
 
-
     provide_project_or_context_for_view
 
     # this is set after save and cleared after reload, so save it here
@@ -1138,18 +1138,18 @@ end
   end
 
   def count_old_due_empty(id)
-    due_today_date = Time.zone.now
-    due_this_week_date = Time.zone.now.end_of_week
-    due_next_week_date = due_this_week_date + 7.days
-    due_this_month_date = Time.zone.now.end_of_month
     case id
     when "due_today"
+      due_today_date = Time.zone.now
       return current_user.todos.not_completed.where('todos.due <= ?', due_today_date).count
     when "due_this_week"
+      due_this_week_date = Time.zone.now.end_of_week
       return current_user.todos.not_completed.where('todos.due > ? AND todos.due <= ?', due_today_date, due_this_week_date).count
     when "due_next_week"
+      due_next_week_date = due_this_week_date + 7.days
       return current_user.todos.not_completed.where('todos.due > ? AND todos.due <= ?', due_this_week_date, due_next_week_date).count
     when "due_this_month"
+      due_this_month_date = Time.zone.now.end_of_month
       return current_user.todos.not_completed.where('todos.due > ? AND todos.due <= ?', due_next_week_date, due_this_month_date).count
     when "due_after_this_month"
       return current_user.todos.not_completed.where('todos.due > ?', due_this_month_date).count
diff --git a/test/controllers/todos_controller_test.rb b/test/controllers/todos_controller_test.rb
index 509ea9f5..a419492b 100644
--- a/test/controllers/todos_controller_test.rb
+++ b/test/controllers/todos_controller_test.rb
@@ -440,6 +440,14 @@ class TodosControllerTest < ActionController::TestCase
     assert_equal context.id, todo.reload.context.id, 'context of todo should be changed'
   end
 
+  def test_update_todo_due_in_calendar_view
+    t = Todo.find(1)
+    login_as(:admin_user)
+    post :update, xhr: true, params: { :id => 1, :_source_view => 'calendar', "context_name"=>"library", "project_name"=>"Build a working time machine", "todo"=>{"id"=>"1", "notes"=>"", "description"=>"Call Warren Buffet to find out how much he makes per day", "due"=>"31/11/2006"}, "tag_list"=>"foo bar" }
+    t = Todo.find(1)
+    assert_response 200
+  end
+
   #######
   # defer
   #######