  In this contribution we review the formal GNS construction developped in a
previous preprint (q-alg/9607019), and formulate the usual WKB-expansion in
flat 2n-dimensional phase space in terms of a GNS construction with a positive
linear functional with support on a projectable Lagrangean submanifold defined
as a graph of an exact one form dS. The main trick is a suitable form of the
star-exponential of S.
