the marker 'x' (ex: plot(a,b,'bx',markersize=5) are not
> working anymore (at least version 0.72.1 and cvs) with Agg
> backend (and TkAgg and GTKAgg). With PS backend it's ok.
OK, thanks for letting me know. This will be fixed in the next bugfix
release of mpl.
JDH