  From any given Frobenius manifold one may construct a so-called dual
structure which, while not satisfying the full axioms of a Frobenius manifold,
shares many of its essential features, such as the existence of a prepotential
satisfying the WDVV equations of associativity. Jacobi group orbit spaces
naturally carry the structures of a Frobenius manifold and hence there exists a
dual prepotential. In this paper this dual prepotential is constructed and
expressed in terms of the elliptic polylogarithm function of Beilinson and
Levin.
