Here are some links for ganttproject on the web...
Home Page : http://ganttproject.sf.nets
Page on sourceforge : http://sf.net/projects/ganttproject
Page on freshmeat : http://freshmeat.net/projects/ganttproject
Page on Gnu : http://www.gnu.org/directory/productivity/project/ganttproject.html
Page on HostScript : http://www.hotscripts.com/Detailed/22019.html
Java Virtual Machine of sun : http://java.sun.com