Unfortunately as a simple content manager for the district section (of a political party) there I don't have ftp-access; I can upload the sitemaps per http.
I know it seems hard to believe but the operators of the national portal are - in this case of the online marketing - mental very 'immobile' ;-)
Do sitemaps loose their effect, if I store them on another domain and ping Google + Bing to find them there?
With respect to a Typo3-Forum - is there one you could/would recommend?
I thought, this is primarily a sitemap-problem, because other cms will react equally.