  We consider the contribution of the B-field into the RR charge of a spherical
D2-brane. Extending a recent analysis of Taylor, we show that the boundary and
bulk contributions do not cancel in general. Instead, they add up to an integer
as observed by Stanciu. The general formula is applied to compute the RR
charges of spherical D-branes of the SU(2) WZW model at level k and it shows
that these RR charges are only defined modulo k+2. We support this claim by
studying bound state formation of D0-branes using boundary conformal field
theory.
