We consider properties of a covariant worldvolume action for a system of N
coincident Dp-branes in D=(p+2) dimensional space-time (so called codimension
one branes). In the case of N coincident D0-branes in D=2 we then find a
generalization of this action to a model which includes fermionic degrees of
freedom and is invariant under target-space supersymmetry and worldline
kappa-symmetry. We find that the type IIA D=2 superalgebra generating the
supersymmetry transformations of the ND0-brane system acquires a non-trivial
"central extension" due to a nonlinear contribution of U(N) adjoint scalar
fields. Peculiarities of space-time symmetries of coincident Dp-branes are
discussed.Comment: LaTeX2e file, 14 pages. Some signs corrected. Version published in
JHE