  We study the macroscopic quantum tunneling of two weakly-linked superfluids
made of interacting fermionic atoms. We derive atomic Josephson junction
equations and find that zero-mode and pi-mode frequencies of coherent atomic
oscillations depend on the tunneling coefficient and the sound velocity of the
superfluid. By considering a superfluid of ^40K atoms, we calculate these
oscillation frequencies in the crossover from the Bardeen-Cooper-Schrieffer
state of weakly-bound Cooper pairs to the Bose-Einstein Condensate of
strongly-bound molecular dimers.
