“…Faddeev and Jackiw [2] have thus proposed an alternative method based on a first order Lagrangean (symplectic) formulation, avoiding the introduction of primariy constraints. Furthermore, the local symmetries of the Hamiltonian, as generated by the so called "first-class" constraints in Dirac's terminology, turn out to be larger than those of the Lagrangean This has led to a renewed interest in the problem of deducing the local symmetries of a Lagrangean from the Hamiltonian formalism [3], and in particular to a revival of the "Lagrangean approach", and the "symplectic approach" to constrained systems [4,5,6,7,8,9]. Of all three methods, the Lagrangean algorithm is actually the most pedestrian one, with a solid mathematical basis.…”