My auctex renders preview images on my debian stable system (6.0.6) if I set it to dvi mode, but it fails if I set auctex to pdf mode.

I assume there is either a mistake in my emacs configuration or a permanent bug in the ghostscript package.
I need help to isolate the bug step by step. Additionally I would be glad, if someone with the same software could help me out with his configuration.
Perhaps it will help, if I can upgrade the ghostscript package, but I have no idea how to do this as I found no backport yet.
My complete emacs configuration is available on github.
$ ghostscript --version
8.71
$ emacs-snapshot --version
GNU Emacs 24.2.50.1
$ pdftex --version
pdfTeX 3.1415926-1.40.10-2.2 (TeX Live 2009/Debian)
.dvifiles (which are needed bypreview). I'm therefore wondering if this can possibly work! – Joseph Wright♦ Oct 27 '12 at 18:25.dvisettings. – Jonas Stein Oct 27 '12 at 19:32