When the look and feel:

com.sun.java.swing.plaf.gtk.GTKLookAndFeel

specified to netbeans with the arguments:

--laf  com.sun.java.swing.plaf.gtk.GTKLookAndFeel

I can not realize a diff operation with the subversion plugin, I obtain the
following exception:

java.lang.NullPointerException
	at
org.netbeans.modules.subversion.ui.diff.MultiDiffView.addPropertyChangeListener(MultiDiffView.java:277)
	at javax.swing.plaf.synth.SynthPanelUI.installListeners(SynthPanelUI.java:49)
	at javax.swing.plaf.synth.SynthPanelUI.installUI(SynthPanelUI.java:38)
	at javax.swing.JComponent.setUI(JComponent.java:668)
	at javax.swing.JPanel.setUI(JPanel.java:136)
	at javax.swing.JPanel.updateUI(JPanel.java:109)
	at javax.swing.JPanel.<init>(JPanel.java:69)
	at javax.swing.JPanel.<init>(JPanel.java:92)
	at javax.swing.JPanel.<init>(JPanel.java:100)
	at
org.netbeans.modules.subversion.ui.diff.MultiDiffView.<init>(MultiDiffView.java:95)
	at
org.netbeans.modules.subversion.ui.diff.DiffMainPanel$DiffPrepareTask.run(DiffMainPanel.java:660)
	at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:499)
[catch] at
org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:932)

I hope this helps, thanks a lot for all the great work you are doing.

Eduardo Narros