  The excess of solar-neutrino events above 13 MeV that has been recently
observed by Superkamiokande can be explained by the vacuum oscillation solution
to the Solar Neutrino Problem (SNP). If the boron neutrino flux is 20% smaller
than the standard solar model (SSM) prediction and the chlorine signal is
assumed 30% (or 3.4 sigmas) higher than the measured one, there exists a vacuum
oscillation solution to SNP that reproduces both the observed spectrum of the
recoil electrons, including the high energy distortion, and the other measured
neutrino rates. The most distinct signature of this solution is a semi-annual
seasonal variation of the Be7 neutrino flux with maximal amplitude. While the
temporal series of the GALLEX and Homestake signals suggest that such a
seasonal variation could be present, future detectors (BOREXINO, LENS and
probably GNO) will be able to test it.
