Index: storage/myisam/ha_myisam.h
===================================================================
--- storage/myisam/ha_myisam.h	(revision 12926)
+++ storage/myisam/ha_myisam.h	(working copy)
@@ -58,6 +58,7 @@
   uint max_supported_keys()          const { return MI_MAX_KEY; }
   uint max_supported_key_length()    const { return MI_MAX_KEY_LENGTH; }
   uint max_supported_key_part_length() const { return MI_MAX_KEY_LENGTH; }
+  uint max_supported_key_parts() const { return MI_MAX_KEY_SEG; }
   uint checksum() const;
 
   int open(const char *name, int mode, uint test_if_locked);
Index: sql/unireg.h
===================================================================
--- sql/unireg.h	(revision 12926)
+++ sql/unireg.h	(working copy)
@@ -51,7 +51,7 @@
 #define MAX_FIELD_NAME 34			/* Max colum name length +2 */
 #define MAX_SYS_VAR_LENGTH 32
 #define MAX_KEY MAX_INDEXES                     /* Max used keys */
-#define MAX_REF_PARTS 16			/* Max parts used as ref */
+#define MAX_REF_PARTS 32			/* Max parts used as ref */
 #define MAX_KEY_LENGTH 3072			/* max possible key */
 #if SIZEOF_OFF_T > 4
 #define MAX_REFLENGTH 8				/* Max length for record ref */