Sitemaps in Typo3

Hello together,

I'm content managing a domain with cms Typo3.
When I generate sitemaps with A1 and upload them to the root directory
I can't open them with a browser because in all cases
- domain.de/
- domain.de/index.php...
- domain.de/sitemap.html
- domain.de/sitemap.xml
- etc. pp.
the cms opens the in typo defined starting file (homepage).
I can't change the configuration of the cms because this domain is only a regional domain of a bigger (national) portal.
What can I do?
Appreciating all hints.

Do you have access to .htaccess file somewhere in the ftp-root / web-root? Othweise, I think this is a question for typo3 forums, but will keep your question here incase someone thinks of a solution!

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.

Tje reneralgrul is you need to have XML sitemaps stored in the domain (or subdomain) root: http://www.microsystools.com/products/sitemap-generator/help/multiple-domains-xml-sitemaps/

But the section "Sitemaps & Cross Submits" of the official XML sitemaps protocol site may be of help since it allows to store XML files on other domains:
http://www.sitemaps.org/protocol.html

But the section "Sitemaps & Cross Submits" of the official XML sitemaps protocol site may be of help since it allows to store XML files on other domains:
http://www.sitemaps.org/protocol.html

O.K. I did the cross submits now.
I've put the sitemaps on
http://dasargument.de/_projekte/die-linke-eimsbuettel-sitemaps/sitemap.xml
and the robots.txt on
http://www.die-linke-eimsbuettel.de/
But I think (not know), that to ping Google now doesn't help, because I can't verify the domain. If I call the google wmt-verification file (stored in the root directory
http://www.die-linke-eimsbuettel.de/google216c6b5a01043e3b.html
of this domain) the server redirects to the index too.
I've applied to make an exception of the redirect-rules for the sitemap.xml but I think I overwhelmed the decision-makers.