  We preesent a new supersymmetric integrable extensions of the a=4,N=2 KdV
hierarchy. The root of the supersymmetric Lax operator of the KdV equation is
generalized, by including additional fields. This generalized root generate new
hierarchy of integrable equations, for which we investigate the hamiltonian
structure. In special case our system describes the interaction of the KdV
equation with the two MKdV equations.
