Abstract :
In the paper “Constraint quantization of open string in background B field and non-commutative D-brane”, [Nucl. Phys. B 568 (2000) 447], it is claimed that the boundary conditions lead to an infinite set of secondary constraints and Dirac brackets result in a non-commutative Poisson structure for D-brane. Here we show that contrary to the arguments in that paper, the set of secondary constraints on the boundary is finite and the non-commutativity algebra cannot be obtained by evaluating the Dirac brackets.