When I don't use one of the default applications in elementary OS I usually hide it from the Applications menu using MenuLibre, rather than uninstalling them. However I can't seem to be able to do that with Nepomuk Cleaner, since as soon as I check "hide from menu" another .desktop entry for said program is created, i.e. if I hide "nepomukcleaner.desktop", as soon as I save those changes another file (something like "nepomukcleaner1.desktop") is created, and shows up alongside the previous, now hidden, entry. If I try to hide this one, a third .desktop file is created, and so on. Same thing happens if I try to delete it.