  We discuss the classical solutions of the equations of motion and the
possible boundary condition for a bosonic string with Kalb-Ramond background in
AdS3. It turns out that there exists three different physical sectors and that
it is also possible to describe the motion on an extremal black hole
background. The existence of three sectors clearly shows how one of the spectra
proposed is incomplete. We consider also the classical 'canonical'
transformation which maps the string fields to the classical Wakimoto ones. It
turns however out that the Wakimoto fields are not free because of the boundary
conditions and in order to have the usual mode expansion with reasonable
behaviour under complex conjugation it is necessary to consider the
complexification of AdS3 and then add some constraints. Furthermore they cover
only half AdS3 and we need different patches to cover the whole space and to
make the above mentioned transformation really canonical.
