FileDialog throws NPE when selecting /media/floppy on Linux, XToolkit

I am running an application which opens up a FileDialog. I am selecting the root of the file system ('/'). After that, I am selecting /media/floppy folder. As soon as I click the floppy folder, a NPE is thrown on the console.

This is reproducible only on Linux with all mustang, tiger builds with XAWT. Not reproducible on Motif. Not reproducible on SolSparc. I reproduced it with Mustang-b61 on Cinnabar as well as SuSE10.

I have attached a sample test. Execute the sample test. Click one of the buttons shown on the frame. A file dialog would appear. Navigate to /media/floppy folder. You would see a NullPointerException on the console.

Here is the exception:

java.lang.NullPointerException
at java.util.Arrays.sort(Arrays.java:1081)
at sun.awt.X11.XFileDialogPeer.setFilterEntry(XFileDialogPeer.java:427)
at sun.awt.X11.XFileDialogPeer.handleFilter(XFileDialogPeer.java:341)
at sun.awt.X11.XFileDialogPeer.actionPerformed(XFileDialogPeer.java:560)
at java.awt.List.processActionEvent(List.java:1108)
at java.awt.List.processEvent(List.java:1044)
at java.awt.Component.dispatchEventImpl(Component.java:4365)
at java.awt.Component.dispatchEvent(Component.java:4195)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:177)
at java.awt.Dialog$1.run(Dialog.java:1032)
at java.awt.Dialog$2.run(Dialog.java:1078)
at java.security.AccessController.doPrivileged(Native Method)
at java.awt.Dialog.show(Dialog.java:1076)
at java.awt.Component.show(Component.java:1406)
at java.awt.Component.setVisible(Component.java:1359)
at java.awt.Window.setVisible(Window.java:695)
at java.awt.Dialog.setVisible(Dialog.java:972)
at FileDialogTest.actionPerformed(FileDialogTest.java:36)
at java.awt.Button.processActionEvent(Button.java:388)
at java.awt.Button.processEvent(Button.java:356)
at java.awt.Component.dispatchEventImpl(Component.java:4365)
at java.awt.Component.dispatchEvent(Component.java:4195)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)