Toots I've only made that mistake once! A ~pinch~ of cinnamon into the recipe would be okay, but replacing the nutmeg with it burns incredibly bad and doesn't even have the same effect as the nutmeg does.
I've tried most everything on the spice rack and nothing is the same as the nutmeg... Cumin is a good substitute though.
Nutmeg recipes for internal probably isn't a bad idea! : )