  We discuss the issue of how to include magnetic charges in the AdS(4)
superalgebra osp(4|2). It is shown that the usual way of introducing a
pseudoscalar central charge on the right hand side of the basic anticommutator
does not work, because this breaks SO(2,3) covariance. We propose a way out by
promoting the magnetic charge to a vector charge, which amounts to enlarge
osp(4|2) to the superconformal algebra su(2,2|1). The conditions for 1/4, 1/2
and 3/4 BPS states are then analyzed. These states form the boundary of the
convex cone associated with the Jordan algebra of 4x4 complex hermitian
matrices. An Inonu-Wigner contraction of the constructed superalgebra yields a
known extension of the Poincare' superalgebra containing electric and magnetic
0-brane charges as well as string- and space-filling 3-brane charges. As an
example, we show how some supersymmetric AdS(4) black holes fit into the
classification scheme of BPS states.
