Index lengths not retrieved using drizzledump

drizzle> show create table t1\G
*************************** 1. row ***************************
       Table: t1
Create Table: CREATE TABLE `t1` (
  `a` INT DEFAULT NULL,
  `b` TEXT COLLATE utf8_general_ci,
  KEY `b` (`b`(20))
) ENGINE=InnoDB COLLATE = utf8_general_ci
1 row in set (0 sec)

Drizzledump:

DROP TABLE IF EXISTS `t1`;
CREATE TABLE `t1` (
  `a` INT DEFAULT NULL,
  `b` TEXT COLLATE utf8_general_ci DEFAULT NULL,
  KEY `b` (`b`)
) ENGINE=InnoDB COLLATE = utf8_general_ci;