Production of $J/��$-pairs at HERA-$\vec{\rm N}$

The production of $J/��$-pairs as a possible measure of the polarized gluon distribution $��G(x)$ is studied for proton--nucleon collisions at $\sqrt{s} =40\;\mbox{GeV}^2$ (HERA-$\vec{\rm N}$). Possibilities of reconstructing the helicity state of at least one of the $J/��$'s are critically reviewed. The observation of production asymmetries in the single polarized mode of HERA-$\vec{\rm N}$ is found to be not feasible.
8 pages, LATeX, 3 figures availabe as .uu-file