gnuplot_x11 driver with octave.app/gnuplot.app on Mac

[Henry F. Mollet]

I want to use gnuplot_x11 instead of AquaTerm for plots when using
octave.app/gnuplot.app in xterm window.
"GNUTERM=X11" does not work (see below)

It works with octave-2.1.71/gnuplot-4.0 in xterm windwow.
Henry

henry-f-mollets-emac:~ hfm$ GNUTERM=X11
henry-f-mollets-emac:~ hfm$
/Applications/Octave.app/Contents/Resources/bin/octave

GNU Octave, version 2.9.13
Copyright (C) 2007 John W. Eaton and others.

octave-2.9.13:1> fplot('cos',[0,2*pi])
Expected X11 driver: /tmp/gnuplot-ppc/libexec/gnuplot/4.2/gnuplot_x11
See 'help x11' for more details
/Applications/Gnuplot.app/Contents/Resources/bin/gnuplot: line 57:   694
Broken pipe             "${ROOT}/bin/gnuplot-4.2.0" "$@"

[~] -bash-2.05b 502$ locate gnuplot_x11
/Applications/GnuPlot.app/Contents/Resources/libexec/gnuplot/4.2/gnuplot_x11
/usr/local/libexec/gnuplot/4.0/gnuplot_x11