PDOException following enable of feeds_import

Downloaded Feeds 7.x-2.0-alpha3 via drush dl. Enabled feeds and feeds_ui via admin with no errors. Enabled feeds_import via admin and received error below. I've only installed Feeds dependencies (Ctools, Job Scheduler). Reproduced on stable CentOS box and local MAMP installation.

I have not encountered this error with earlier alpha2 version.

PDOException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry 'fetch_task::Feeds' for key 'PRIMARY': INSERT INTO {cache_update} (cid, created) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1); Array ( [:db_insert_placeholder_0] => fetch_task::Feeds [:db_insert_placeholder_1] => 1298008691 ) in _update_create_fetch_task() (line 246 of /srv/www/mysite.com/public_html/mode/modules/update/update.fetch.inc).