Default font and umlauts

[Andreas Neiser <andreas.neiser@gmail.com>]

Hi all,
first I hope this is the correct mailing list for my problem. Anyway,
I'm experiencing a strange problem with German umlauts while setting the
default font with the following lines in my ~/.emacs

(set-frame-parameter nil 'font-backend '(xft))
(set-frame-font "Terminus-12")

So, the umlauts ä, ö, ü work with the default font, but see the
following screenshot

http://student.physik.uni-mainz.de/~aneiser/emacs.png

It seems that emacs displays umlauts always in the default font and some
special font selections (I guess this is what auctex does) are not handled?
There was also the problem when selecting the default font from the Menu
Options->Set default font. In this case the font was changed but the
font for the umlauts did not... Seems strange to me. If anyone has some
suggestions in debugging this further, misses some information or has
some fix, feel free to tell me :)
I use the CVS version from 20090319, hope this is recent enough.
Thanks for an answer
Andreas