pcolor/plot: marker is hidden

[x,y,z]=peaks(10);
h1 = pcolor(x,y,z);shading flat;hold on;
h=plot(0,0,'+');

the marker does not appear

set(h,'markersize',1000);

it is "behind" the map

[clev,h2] = contour(x,y,z,5);

the marker appears now in front.

octave:38> version
ans = 3.0.0
gnuplot

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        Version 4.2 patchlevel 2
        last modified 31 Aug 2007