--- chicken.h~	2009-08-29 15:25:32.000000000 +0200
+++ chicken.h	2009-08-29 15:27:46.000000000 +0200
@@ -49,7 +49,9 @@
 /* Kind of platform */
 
 #ifndef C_SIXTY_FOUR
-# if defined (__alpha__) || defined (__sparc_v9__) || defined (__sparcv9) || defined(__ia64__) || defined(__x86_64__) || defined(__LP64__) || defined(__powerpc64__)
+# if defined (__alpha__) || defined(__ia64__) || defined(__x86_64__) || defined(__LP64__) || defined(__powerpc64__)
+#   define C_SIXTY_FOUR
+# elif (defined(__sparc_v9__) || defined(__sparcv9)) && defined(__arch64__)
 #   define C_SIXTY_FOUR
 # elif defined(__mips64) && (!defined(__GNUC__) || _MIPS_SZPTR == 64)
 #   define C_SIXTY_FOUR