  We show that the well known $N=1$ NLS equation possesses $N=2$ supersymmetry
and thus it is actually the $N=2$ NLS equation. This supersymmetry is hidden in
terms of the commonly used $N=1$ superfields but it becomes manifest after
passing to the $N=2$ ones. In terms of the new defined variables the second
Hamiltonian structure of the supersymmetric NLS equation coincides with the
$N=2$ superconformal algebra and the $N=2$ NLS equation belongs to the $N=2$
$a=4$ KdV hierarchy. We propose the KP-like Lax operator in terms of the $N=2$
superfields which reproduces all the conserved currents for the corresponding
hierarchy.
