BLOB/TEXT column 'titles' can't have a default value

PDOException: SQLSTATE[42000]: Syntax error or access violation: 1101 BLOB/TEXT column 'titles' can't have a default value: CREATE TABLE {custom_breadcrumb} ( `bid` INT unsigned NOT NULL auto_increment COMMENT 'Unique identifier for the custom_breadcrumb.', `name` VARCHAR(128) NULL DEFAULT NULL COMMENT 'An optional name for the custom breadcrumb.', `titles` MEDIUMTEXT NOT NULL DEFAULT '' COMMENT 'A return-delimited list of titles for the breadcrumb links.', `paths` MEDIUMTEXT NOT NULL COMMENT 'A return-delimited list of url paths for the breadcrumb links.', `visibility_php` MEDIUMTEXT NOT NULL COMMENT 'An optional PHP snippet to control the custom_breadcrumb visibility.', `node_type` VARCHAR(64) NULL DEFAULT 'AND' COMMENT 'Node types the custom_breadcrumb should apply to.', `language` VARCHAR(12) NOT NULL DEFAULT '' COMMENT 'The language this breadcrumb is for; if blank, the breadcrumb will be used for unknown languages.', PRIMARY KEY (`bid`), INDEX `language` (`language`), INDEX `node_language` (`node_type`, `language`) ) ENGINE = InnoDB DEFAULT CHARACTER SET utf8 COMMENT 'Stores custom breadcrumb trail overrides.'; Array ( ) in db_create_table() (line 2688 of /opt/www/apstudents/includes/database/database.inc).