###@###.### 2002-02-19

-- A minor inconvenience is that one apparently cannot use
myJButton.getRootPane().setDefaultButton(myJButton) to set the default
button while constructing a JInternalFrame, since the button apparently does
not yet know what its root pane is.

Since root panes (and not buttons)control default-ness, it's inconvenient
when trying to manage default-ness during the constructor of a JInternalFrame
(adding a button to the content pane apparently does not immediately make
root pane aware of the button).