  We study behaviour of dynamical critical exponents of the two-dimensional
Ising model with a line of defects. Simulations done at an early time (first
100 Monte Carlo steps) reveal that the critical exponent of Janssen et al (Z.
Phys. B 73 539) depends on the strength of the exchange coupling constant (J')
of the altered line. On the other hand, our simulations permit us to conclude
that the dynamical critical exponent z is not sensitive to changes in J'. In
adition, we investigate the possible invariance of the anomalous dimension of
the magnetization at the beginning of the process.
