  In answer to a question of A. Blass, J. Irwin and G. Schlitt, a subgroup G of
the additive group Z^{\omega} is constructed whose dual, Hom(G,Z), is free
abelian of rank 2^{\aleph_0}. The question of whether Z^{\omega} has subgroups
whose duals are free of still larger rank is discussed, and some further
classes of subgroups of Z^{\omega} are noted.
