  This is an old paper put here for archeological purposes. We compute the
second cohomology of current Lie algebras of the form $L\otimes A$, where $L$
belongs to some class of Lie algebras which includes classical simple and
Zassenhaus algebras, and of some modular semisimple Lie algebras. The results
are largely superseded by subsequent papers, though, perhaps, some tricks and
observations used here remain of minor interest.
