Receiving unknown column NaN error

Issue Summary

Entering to http://masmapas.com/mapa/mapa-de-madrid and cliking over one marker and without zooming previously I'm receiving this error twice, no matter of admin or anon:

mysite... /?q=geobrowser_xml_controller&function=map_node&layer0=45,44,43,42&nid=33&current_tree=0&lat_min=40.35151549537612&lat_max=40.4822093912065&lon_min=NaN&lon_max=NaN
Referred http://masmapas.com/?q=geobrowser/33
Mensaje Unknown column 'NaN' in 'where clause' query: SELECT location.latitude AS geobrowser_lat, location.longitude AS geobrowser_lon, location.eid AS geobrowser_vid, node.nid AS geobrowser_nid, tid0 as term_node_tid, node.title AS node_revisions_title, votingapi_vote.value IS NULL AS isnull FROM location INNER JOIN node ON node.vid = location.eid INNER JOIN (SELECT nid, tid as tid0 from term_node WHERE term_node.tid IN (45,44,43,42) GROUP BY nid, tid ) AS geobrowsertemptable ON node.nid = geobrowsertemptable.nid LEFT JOIN votingapi_vote ON node.nid = votingapi_vote.content_id WHERE node.status = 1 AND location.longitude < NaN AND location.longitude > NaN AND location.latitude < 40.4822093912065 AND location.latitude > 40.35151549537612 ORDER BY isnull ASC, votingapi_vote.value ASC LIMIT 0, 30 en la línea 172 del archivo /home/masmapas/public_html/includes/database.mysql.inc.

Zooming previosuly, and without less error margin when pointing and clicking, things go ok.

Thanks for your support.
Gustavo