Altering partitioned table into S3 causes an obscure error

MariaDB [elenst]> create table t1 (a int) partition by hash(a);

Query OK, 0 rows affected (0.477 sec)

MariaDB [elenst]> alter table t1 engine=S3;

ERROR 155 (HY000): Table elenst.#sql-45b7_a#P#p0 doesn't exist in s3

MariaDB [elenst]> show warnings;                   

+-------+------+--------------------------------------------------------------------------------------------------------------------------+

| Level | Code | Message                                                                                                                  |

+-------+------+--------------------------------------------------------------------------------------------------------------------------+

| Error |  155 | Table elenst.#sql-45b7_a#P#p0 doesn't exist in s3                                                                        |

| Error | 1025 | Error on rename of './elenst/#sql-45b7_a' to './elenst/t1' (errno: 155 "The table does not exist in the storage engine") |

+-------+------+--------------------------------------------------------------------------------------------------------------------------+

2 rows in set (0.000 sec)