  New CP-violating asymmetries of decay leptons in $e^+\,e^-\;\ra\;t\,\bar{t}$,
arising from electric and weak dipole couplings of $t\,\bar{t}$ to $\gamma$ and
$Z$, are examined in the case of unpolarized and longitudinally polarized
electrons. The new asymmetries measured together with the old ones can help to
determine independently the real and imaginary parts of the electric as well as
weak dipole couplings. Longitudinal beam polarization, if present, obviates the
need for the simultaneous measurement of more than one asymmetry, and enhances
considerably the sensitivity to the CP-violating parameters. Numerical results
are presented for the Next Linear Collider with $\sqrt{s}=500$ GeV and
$\int{\cal L}\,dt\;=\;10\,{\rm fb}^{-1}$.
