ha_innodb.h, ha_innodb.cc:

  Reverted the change which allowed use of HA_READ_PREFIX_LAST in InnoDB

sql/ha_innodb.cc

@@ -2004,7 +2004,11 @@ convert_search_mode_to_innobase(
 		case HA_READ_AFTER_KEY:		return(PAGE_CUR_G);
 		case HA_READ_BEFORE_KEY:	return(PAGE_CUR_L);
 		case HA_READ_PREFIX:		return(PAGE_CUR_GE);
-		case HA_READ_PREFIX_LAST:	return(PAGE_CUR_LE);
+		case HA_READ_PREFIX_LAST:	ut_a(0); return(PAGE_CUR_LE);
+		        /* InnoDB does not yet support ..PREFIX_LAST!
+		        We have to add a new search flag
+		        PAGE_CUR_LE_OR_PREFIX to InnoDB. */
+
 			/* the above PREFIX flags mean that the last
 			field in the key value may just be a prefix
 			of the complete fixed length field */

sql/ha_innodb.h

@@ -96,7 +96,7 @@ class ha_innobase: public handler
 	ulong index_flags(uint idx) const
 	{
 	  return (HA_READ_NEXT | HA_READ_PREV | HA_READ_ORDER |
-		  HA_KEY_READ_ONLY);
+		  HA_KEY_READ_ONLY | HA_NOT_READ_PREFIX_LAST);
 	}
   	uint max_record_length() const { return HA_MAX_REC_LENGTH; }
   	uint max_keys()          const { return MAX_KEY; }