pt-online-schema-change --data-dir option broken for partitioned table

mkdir -p /data/db/data1; chown mysql:mysql -R /data/db ; ./pt-online-schema-change --data-dir="/data/db/data1" --execute  --alter "engine=innodb" D=test,t=t
No slaves found.  See --recursion-method if host fd0b85b08720 has slaves.
Not checking slave lag because no slaves were found and --check-slave-lag was not specified.
Operation, tries, wait:
  analyze_table, 10, 1
  copy_rows, 10, 0.25
  create_triggers, 10, 1
  drop_triggers, 10, 1
  swap_tables, 10, 1
  update_foreign_keys, 10, 1
Altering `test`.`t`...
Creating new table...
`test`.`t` was not altered.
Error creating new table: DBD::mysql::db do failed: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DATA DIRECTORY='/data/db/data1'' at line 5 [for Statement "CREATE TABLE `test`.`_t_new` (
  `c` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
/*!50100 PARTITION BY HASH (c)
PARTITIONS 4 */ DATA DIRECTORY='/data/db/data1' "] at ./pt-online-schema-change line 10342.

CREATE TABLE `test`.`_t_new` (   `c` int(11) DEFAULT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1 DATA DIRECTORY='/data/db/data1' /*!50100 PARTITION BY HASH (c) PARTITIONS 4 */;