  The accepted resolution of the twin paradox in relativity states that the age
of the inertial twin `jumps' when the traveling twin undergoes his turn-around
acceleration. This resolution is based on the use of the equivalent
gravitational shift in the frame of the accelerating twin. We use the same
analysis to propose a symmetric variant of the problem with the twins
experiencing identical acceleration and deceleration phases, but which predicts
conflicting results for the age of the other twin. We also propose an
unambiguous test of the standard resolution based on the Pound-Rebka
experiment.
