Override sysLocation appears to not update DB

It appears that the 'Override sysLocation' is not updating the 'location' field in the database with the 'Custom Location' entry from the web interface. This may be a bug introduced at some stage, as it has worked in previous versions.

It could be an issue with versions updated, I've not had a chance to test a new install, however I've replicated it with 3 separate systems running both current and stable trees. I have also tried to re-install a system and copy over only the RRDs/logs/config.php, keeping the updated database schema.

Running the poller in debug mode shows a large SQL query at the end, which when manually running in MySQL shows an error with the SQL syntax near 'location_lon' and 'location_lat', as it seems to be trying to enter a NULL value.

I have
$config['geocoding']['enable'] = FALSE;
$config['location_menu_geocoded'] = FALSE;

Happy to help out with any debugging required.

Many thanks,
Duncan