Comment 2 for bug 1073247

At least on Ubuntu 12.04 it seems there are two Problems involved:

1. asciidoc does not convert german-umlauts in xref-labels for the xml-output.
A workaround is to manually give plain ascii xref-labels if a header contains german umlauts and you need the xreference. Otherwise just ignore them.

2. texlive is not installed with utf-support by default, so pdflatex are unable to parse the generated output from asciidoc.
On Ubuntu you have to install the cyrillic-texlive package, which includes utf8 support.

sudo apt-get install texlive-lang-cyrillic

Now you have to tell asciidoc and dblatex to use it

a2x -a encoding=utf-8 -a lang=de --dblatex-opts='-P latex.encoding=utf8 -P latex.unicode.use=1' -v test.asciidoc

This works well with umlauts, but probably fails with the german sharp s (ß). So you have to set manual xrefs here, even if you don't use them.