URL with umlauts don't work. Any äöüß will destroy the URL

If you write a URL like www.füße.de or anything other with a ä,ü,ö,ß in it the URL is damaged.
If you use the BBCode wrapped around the URL the BBCode and URL will be posted as clean text (Example 1), if you use the automatic URL-linker the URL-link is cutted at the first umlaut (Example 2).