Win32/Solaris, SwingSet2, JTable tab. Click a cell in 'Favorite
    Color' column to bring up a color choice popup, press 'Enter' to
    close it. Then press 'down' key again and the following exception
    will be thrown:
    java.awt.IllegalComponentStateException: component must be showing on the screen to determine its location
        at java.awt.Component.getLocationOnScreen_NoTreeLock(Component.java:1321)
        at java.awt.Component.getLocationOnScreen(Component.java:1295)
        at javax.swing.JPopupMenu.show(JPopupMenu.java:718)
        ...

Reproducible for some time now, first reported in Java2D integration comment
on 09.11.00.
Still present on build b38.

dmitri.trembovetski@eng 2000-10-26