Database error after 3.5.1 upgrade

Hi, after upgrading från 3.4.2 to 3.5.1 this weekend we recieve alot of errors in the webserver logs like this:

[Mon Feb 18 08:29:10 2013] [error] [client] WordPress database error fxc3xb6r fxc3xb6rfrxc3xa5gan SELECT ID, guid FROM wp_2317_posts WHERE post_status='publish' AND post_type = 'post' ORDER BY ID DESC limit 1000, 10 created by do_action('wp_ajax_autosave'), call_user_func_array, wp_ajax_autosave, edit_post, wp_update_post, wp_insert_post, wp_transition_post_status, do_action('transition_post_status'), call_user_func_array, sitewide_tags_remove_posts, m_wpdb->query, referer: http://ablog.ourdomain.tld/wp-admin/post-new.php

“caused by” can be different things like build in functions and some plugins.

Site seems to be running fine anyway but the errorlogs on the webservers are filling up fast.

I have re-upgraded and cleared out all caches (incl mysql query cache) but problem persist.

We have another site running fine with same version of WP and plugins but only difference is that it does not run on multi-db like this one.

So, could these errors be caused by multi-db?