[XeTeX] polyglossia and biblatex

[Thomas Bohn]

Hello,

I have a problem with the workings of polyglossia and biblatex. My  
polyglossia setting looks like this:

\usepackage{polyglossia}
\setmainlanguage{german}
\setotherlanguage{english}

and my biblatex setting looks like this:

\usepackage[bibtex8=true,block=space,style=authoryear-comp]{biblatex}

Normaly my bibliography should be displayed in German but it is in  
English.

I really hope someone has an idea to solve this problem.

Thomas