--- a/hotspot/src/share/vm/memory/generation.hpp	Wed Jul 28 17:57:43 2010 -0400
+++ b/hotspot/src/share/vm/memory/generation.hpp	Tue Aug 03 08:13:38 2010 -0400
@@ -131,7 +131,9 @@
   enum SomePublicConstants {
     // Generations are GenGrain-aligned and have size that are multiples of
     // GenGrain.
-    LogOfGenGrain = 16,
+    // Note: on ARM we add 1 bit for card_table_base to be properly aligned
+    // (we expect its low byte to be zero - see implementation of post_barrier)
+    LogOfGenGrain = 16 ARM_ONLY(+1),
     GenGrain = 1 << LogOfGenGrain
   };