"16" = "AquaTerm 1.0 or later is required to install this version of gnuplot. Download it from http://aquaterm.sourceforge.net

If you do have AquaTerm installed, please file a bug report at http://gnuplot.sourceforge.net";
"17" = "X11 is required to install this version of gnuplot. Install it from your Mac OS 10.3 install CD. If you are running 10.0 - 10.2.8, get X11 from e.g. http://www.xfree86.org

If you do have X11 installed, please file a bug report at http://gnuplot.sourceforge.net";
"18" = "AquaTerm 1.0 or later and X11 are required to install this version of gnuplot. Download AquaTerm from http://aquaterm.sourceforge.net and install X11 from your Mac OS 10.3 install CD. If you are running 10.0 - 10.2.8, get X11 from e.g. http://www.xfree86.org 

If you do have AquaTerm and X11 installed, please file a bug report at http://gnuplot.sourceforge.net"