  Magnetization, DC and AC bulk susceptibility of the $S$=1 Haldane chain
system doped with electronic holes, Y$_{2-x}$Ca$_x$BaNiO$_5$
(0$\leq$x$\leq$0.20), have been measured and analyzed. The most striking
results are (i) a sub-Curie power law behavior of the linear susceptibility,
$\chi (T)$$\sim $ $T$$^{-\alpha}$, for temperature lower than the Haldane gap
of the undoped compound (x=0) (ii) the existence of a spin-glass thermodynamic
transition at $T$$_g$ = 2-3 K. These findings are consistent with (i) random
couplings within the chains between the spin degrees of freedom induced by hole
doping, (ii) the existence of ferromagnetic bonds that induce magnetic
frustration when interchain interactions come into play at low temperature.
