JLabel.setIcon() has no effect on the default disabled icon of a JLabel.

When a JLabel with an icon is disabled, a grayed out version of the label's
icon is displayed. If the icon of the label is then changed by invoking setIcon(), and the label is disabled again, a grayed out version of the
icon that had been displayed when the label had first been disabled is displayed.

setIcon() should cause the disabled icon of a JLabel to be changed to a
grayed out version of the label's _new_ icon. If setIcon() is not expected
to do this, this behavior should be clearly documented in the JLabel spec.

The attached application displays a text-and-image JLabel. To recreate
this scenario, disable and enable the label, use the combobox to change the label's icon, and then disable the label again.