--- old/src/macosx/classes/sun/awt/CGraphicsDevice.java	2012-10-04 17:30:07.000000000 +0400
+++ new/src/macosx/classes/sun/awt/CGraphicsDevice.java	2012-10-04 17:30:07.000000000 +0400
@@ -194,6 +194,9 @@
 
     @Override
     public void setDisplayMode(DisplayMode dm) {
+        if (dm == null) {
+            throw new IllegalArgumentException("Attempt to set null as a DisplayMode");
+        }
         nativeSetDisplayMode(displayID, dm.getWidth(), dm.getHeight(), dm.getBitDepth(), dm.getRefreshRate());
         if (isFullScreenSupported() && getFullScreenWindow() != null) {
             getFullScreenWindow().setSize(dm.getWidth(), dm.getHeight());