Nimbus and GTK LaFs don't honor SplitPaneDivider.draggingColor property; consider enhancement.

I'm attaching just for illustration a short manual regression test written for RFE JDK-4820080. Try to run it setting -Dswing.defaultlaf=javax.swing.plaf.nimbus.NimbusLookAndFeel. Note the line
UIManager.put("SplitPaneDivider.draggingColor", Color.green);

Drag the dividers; color doesn't change to green.
This test works OK for Metal, Motif and on OS X, for Aqua LaF.
It fails for Nimbus and GTK. With GTK, a correspondent INTJDK bug was closed long ago with resolution "So in order to get the drag color you should update the .gtkrc file."

Please consider either to implement JDK-4820080 for Nimbus (and GTK) or decline explicitly with "Will not fix".