  The projected SO(5) theory (pSO(5)) is used to resolve the puzzle of two
distinct energy gaps in high T$_c$ Superconductor-Normal-Superconductor
junctions. Counter to conventional theory of multiple Andreev reflections
(MAR), the differential resistance peaks are associated with the
antiferromagnetic resonance observed in neutron scattering, and not with Cooper
pair breaking. The pSO(5) and MAR theories differ by the expected tunneling
charges at the peaks. We propose that shot noise experiments could discriminate
against the conventional interpretation.
