I found this with the Tray Icon object as well, had to delete the object and re-create it. Might want to check this too Yves. I don't have the old code but Everytime I want to 'Fix the issues I have. Deleting the object and re adding it in seems a little harsh because I have to re-create the events associated with it.
You should try renaming the 1st object and create another one, than in the event editor right click the 1st object and select "Replace by another object."