Dennis,
I have an unknown which is similar. When I bought it at a nursery in Houston many years ago, it had three names on the label 'Chicago Hardy', Jelly, and 'Arkansas Black' (which is an apple). As it turns out, it has as much of a chance of being an apple as it does either of the other two. At the time I posted pics in the Gardenweb forum, but it remained unidentified. Both the leaves and fruit are close, but not exact.
It is one of my RKN+ trees which survived last year. I am planning on heat treating the roots this year and planting it into the ground..
~james
pics from 05.2006