Paul,
I don't have one of either at hand to try, but I believe they will fit the same dropouts. I'm not sure about differences in how the torque-reaction arm/tab is secured.
However, as I recall, the cabling for the Alfine is on the right side, while the Rohloff is on the left, so that might be problematic if it proves true.
Sorry I can't be of more definitive help, but perhaps this will help a bit.
Best,
Dan.
