I get this error on OS X when I try to open the dialog window for entering your attributes by clicking on the "New Attribute Set..." item in the context menu of the "Attribute Set Manager" window :
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bash-2.05a$ Java/FOA/foa.sh
apple.awt.EventQueueExceptionHandler Caught Throwable :
java.lang.NullPointerException
        at sun.java2d.SunGraphicsEnvironment.getAvailableFontFamilyNames(SunGraphicsEnvironment.java:327)
        at sun.java2d.SunGraphicsEnvironment.getAvailableFontFamilyNames(SunGraphicsEnvironment.java:359)
        at foa.properties.groups.sets.Font.loadTables(Font.java:68)
        at foa.properties.groups.sets.Font.<init>(Font.java:42)
        at foa.properties.groups.Group.<init>(Group.java:44)
        at foa.properties.groups.Block.<init>(Block.java:35)
        at foa.attributes.AttributeDirector.loadFoClasses(AttributeDirector.java:83)
        at foa.attributes.AttributeDirector.newAttributeSet(AttributeDirector.java:163)
        at foa.attributes.NewAttributeSetAction.actionPerformed(NewAttributeSetAction.java:47)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1797)
        at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1850)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:419)
        at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:257)
        at javax.swing.AbstractButton.doClick(AbstractButton.java:321)
        at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1109)
        at javax.swing.plaf.basic.BasicMenuItemUI$MouseInputHandler.mouseReleased(BasicMenuItemUI.java:943)
        at java.awt.Component.processMouseEvent(Component.java:5093)
        at java.awt.Component.processEvent(Component.java:4890)
        at java.awt.Container.processEvent(Container.java:1566)
        at java.awt.Component.dispatchEventImpl(Component.java:3598)
        at java.awt.Container.dispatchEventImpl(Container.java:1623)
        at java.awt.Component.dispatchEvent(Component.java:3439)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3450)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3165)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3095)
        at java.awt.Container.dispatchEventImpl(Container.java:1609)
        at java.awt.Window.dispatchEventImpl(Window.java:1585)
        at java.awt.Component.dispatchEvent(Component.java:3439)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:450)
        at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:230)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:99)
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Here are some infos about my java runtime :
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bash-2.05a$ java -version
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-69.1)
Java HotSpot(TM) Client VM (build 1.4.1_01-24, mixed mode)
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Does anyone have an idea about this?

Thank you in Advance,

Fred