Good news I understood the functionality on the Extraction tool side, I am back from vacation and sent an email to the admin hosting the mappings wiki server to hopefully recover the callbacks.
In the meanwhile you can manually trigger the updates using HTTP e.g. with curl I managed to the following
curl -X PUT -H "Content-Type: application/xml" -d @mapping.xml http://dief.tools.dbpedia.org/server/mappings/en/pages/Mapping_en:Infobox_country
you can download the mapping.xml with curl like this
curl http://mappings.dbpedia.org/index.php/Special:Export/Mapping_en:Infobox_country > mapping.xml