Fix user migration

I encountered the following error running migration with mysql...
What do you thing about removing the default value in the users.biography field?

    Mysql2::Error: BLOB/TEXT column 'biography' can't have a default value: 
    CREATE TABLE `users` (`id` int(11) DEFAULT NULL auto_increment PRIMARY KEY, `login` varchar(40), `first_name` varchar(20) DEFAULT '', `last_name` varchar(20) DEFAULT '', `biography` text DEFAULT '' NOT NULL, `email` varchar(100), `crypted_password` varchar(40), `salt` varchar(40), `remember_token` varchar(40), `remember_token_expires_at` datetime, `time_zone` varchar(255) DEFAULT 'Eastern Time (US & Canada)', `language` varchar(255) DEFAULT 'en', `first_day_of_week` varchar(255) DEFAULT 'sunday', `invitations_count` int(11) DEFAULT 0 NOT NULL, `login_token` varchar(40), `login_token_expires_at` datetime, `welcome` tinyint(1) DEFAULT 0, `confirmed_user` tinyint(1) DEFAULT 0, `last_read_announcement` int(11), `deleted_at` datetime, `rss_token` varchar(40), `admin` tinyint(1) DEFAULT 0, `comments_count` int(11) DEFAULT 0 NOT NULL, `notify_mentions` tinyint(1) DEFAULT 1, `notify_conversations` tinyint(1) DEFAULT 1, `notify_task_lists` tinyint(1) DEFAULT 1, `notify_tasks` tinyint(1) DEFAULT 1, `avatar_file_name` varchar(255), `avatar_content_type` varchar(255), `avatar_file_size` int(11), `invited_by_id` int(11), `invited_count` int(11) DEFAULT 0 NOT NULL, `created_at` datetime, `updated_at` datetime, `wants_task_reminder` tinyint(1) DEFAULT 1, `recent_projects_ids` text, `feature_level` varchar(255) DEFAULT '', `spreedly_token` varchar(255) DEFAULT '') ENGINE=InnoDB
```