  We compute the universal weight system for Vassiliev invariants coming from
the Lie superalgebra gl(1|1) applying the construction of \cite{YB}. This
weight system is a function from the space of chord diagrams to the center $Z$
of the universal enveloping algebra of gl(1|1), and we find a combinatorial
expression for it in terms of the standard generators of $Z$. The resulting
knot invariants generalize the Alexander-Conway polynomial.
