  Jia and Dutra (J. Phys. A: Math. Gen. 39 (2006) 11877) have considered the
one-dimensional non-Hermitian complexified potentials with real spectra in the
context of position-dependent mass in Dirac equation. In their second example,
a smooth step shape mass distribution is considered and a non-Hermitian non -
PT- symmetric Lorentz vector potential is obtained. They have mapped this
problem into an exactly solvable Rosen-Morse Schrodinger model and claimed that
the energy spectrum is real. The energy spectrum they have reported is pure
imaginary or at best forms an empty set. Their claim on the reality of the
energy spectrum is fragile, therefore.
