--- a/jdk/makefiles/CompileJavaClasses.gmk	Thu Jan 03 20:55:52 2013 +0100
+++ b/jdk/makefiles/CompileJavaClasses.gmk	Fri Jan 04 16:54:41 2013 +0100
@@ -228,14 +228,20 @@
 	sun/nio/ch/SimpleAsynchronousFileChannelImpl.java
 endif
 
-# Exclude nimbus files from rt.jar
+# These files do not appear in the build result of the old build. This
+# is because they are generated sources, but the AUTO_JAVA_FILES won't
+# pick them up since they aren't generated when the source dirs are 
+# searched and they aren't referenced by any other classes so they won't
+# be picked up by implicit compilation. On a rebuild, they are picked up
+# and compiled. Exclude them here to produce the same rt.jar as the old 
+# build does when building just once.
 EXFILES+=javax/swing/plaf/nimbus/InternalFrameTitlePanePainter.java \
-				 javax/swing/plaf/nimbus/OptionPaneMessageAreaPainter.java \
-				 javax/swing/plaf/nimbus/ScrollBarPainter.java \
-				 javax/swing/plaf/nimbus/SliderPainter.java \
-				 javax/swing/plaf/nimbus/SpinnerPainter.java \
-				 javax/swing/plaf/nimbus/SplitPanePainter.java \
-				 javax/swing/plaf/nimbus/TabbedPanePainter.java
+	 javax/swing/plaf/nimbus/OptionPaneMessageAreaPainter.java \
+	 javax/swing/plaf/nimbus/ScrollBarPainter.java \
+	 javax/swing/plaf/nimbus/SliderPainter.java \
+	 javax/swing/plaf/nimbus/SpinnerPainter.java \
+	 javax/swing/plaf/nimbus/SplitPanePainter.java \
+	 javax/swing/plaf/nimbus/TabbedPanePainter.java
 
 # Acquire a list of files that should be copied straight over to the classes.
 include CopyIntoClasses.gmk