auth_ldap_sync_users failing badly when can't create temporary table

The LDAP sync seems to be failing, seems likely to be related to the temp tables (and perhaps lack of XMLDB stuff in ldap sync, remembering the recent discussion on the dev forum). Haven't had a detailed look yet, but:

/usr/bin/php -c /etc/php5/cli/php.ini /var/www/moodle/auth/ldap/auth_ldap_sync_users.php
Configuring temp table
Creating temp table extuser
Connecting to ldap...
+ 4 users
<div class="notifytiny" style="text-align:center">Table 'moodletest.extuser' doesn't exist</div><br />

Notice: Trying to get property of non-object in /var/www/moodle/auth/ldap/auth.php on line 456
Did not get any users from LDAP – error? – exiting

That notice seems to centre around:
$count = get_record_sql('SELECT COUNT(username) AS count, 1 FROM ' . $temptable);