  We discovered that only a weakened version of the main lemma is true. We
state the right version, and the remaining open problem: Is it possible to
approximate holomorphic vector fields (or more generally, sections in a line
bundle) on an open Riemann surface of finite type (i.e. a compact one without a
finite number of points) by meromorphic vector fields (where the poles are
supposed to be in the distinguished points) ? We know that this is true for
functions.
