Support for generating graphical charts in Unanet is accommodated via the jFreeChart jars. If Unanet is being run on a Linux/Unix server you will need to add an additional Java JVM property to support charting.
jFreeChart uses the Java AWT facility when generating graphics. AWT is reliant on a peer graphics component, which is typically X11on Unix variants.
Setting Up Java Platform for Headless Operation
This works only for J2SE v1.4 and later. Add the option -Djava.awt.headless=true to the invocation of java. For example:
java -Djava.awt.headless=true
This is not a requirement for Windows servers since they all have a GUI component by default.