  We show how the (globally supersymmetric) model of Mirabelli and Peskin can
be formulated in the boundary (``downstairs'' or ``interval'') picture. The
necessary Gibbons-Hawking-like terms appear naturally when using (codimension
one) superfields. This formulation is free of the \delta(0) ambiguities of the
orbifold (``upstairs'') picture while describing the same physics since the
boundary conditions on the fundamental domain are the same. The (natural)
boundary conditions follow from the variational principle and form a closed
orbit under supersymmetry variation. They reduce to the ``odd =0'' boundary
conditions in the absence of bulk-boundary coupling. We emphasize that the
action is supersymmetric without the use of any boundary conditions in the
off-shell formulation (but some boundary conditions are necessary for on-shell
supersymmetry!).
