My guess right off hand is that the updated ATM is using DB views that were not completed in 4.0(3) - I don't have a 4.0(3) box to test against - 4.0(5) is the oldest version I have handy and the latest ATM works fine on that.
The best I can suggest is to keep using the old ATM with 4.0(3) until you can upgrade Unity to something a little more recent - I don't have cycles to go back and retrofix ATM back to those older versions of Unity at this point.