  We consider numerical data for the lattice Landau gluon propagator obtained
at very large lattice volumes in three-dimensional pure SU(2) Yang-Mills gauge
theory (YM^2_3). We find that the temporal correlator C(t) shows an oscillatory
pattern and is negative for several values of t. This is an explicit violation
of reflection positivity and can be related to gluon confinement. We also
obtain a good fit for this quantity in the whole time interval using a sum of
Stingl-like propagators.
