Delete confirm forms broken

When hitting the Delete button while trying to delete a book page, I received the error:

    * warning: mysql_real_escape_string() expects parameter 1 to be string, array given in /Applications/MAMP/htdocs/moderation/includes/database.mysql.inc on line 389.
    * user warning: 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 '' at line 1 query: SELECT n.nid, n.vid, n.type, n.status, n.language, n.created, n.changed, n.comment, n.promote, n.sticky, r.timestamp AS revision_timestamp, r.title, r.body, r.teaser, r.log, r.format, u.uid, u.name, u.picture, u.data FROM node n INNER JOIN users u ON u.uid = n.uid INNER JOIN node_revisions r ON r.vid = n.vid WHERE n.#type = 'value' AND n.#value = '2' AND n.#post = '' AND n.#programmed = '' AND n.#tree = '' AND n.#parents = '' AND n.#weight = '' AND n.#processed = '' AND n.#description = '' AND n.#attributes = '' AND n.#required = '' AND n.#input = '' AND n.#name = '' AND n.#id = '' AND n.#sorted = '' in /Applications/MAMP/htdocs/moderation/includes/database.mysql.inc on line 161.

Looks like some FAPI stuff is getting stuck in there..?