-auto-orient not working with convert

Hi there,

I am trying to use the -auto-orient command line option but I can't get it to
work.

I have this image:

http://www.bastiaannaber.com/tmp/cimg1688.jpg

which has exif orientation 6 (right top).

I want to create a thumbnail from it with convert. I give the command:

# convert -auto-orient cimg1688.jpg cimg1688-rot.jpg

I would expect the result to be that the cimg1688-rot.jpg file now contains my
image, but smaller and with the right orientation (photo upright). However
this is not the case:

http://www.bastiaannaber.com/tmp/cimg1688-rot.jpg

I am using Debian testing on a i686 machine using Imagemagick 6.3.7

I hope I am posting in the right place and the -auto-orient is supposed to
work as I expect (I could not find a lot of documentation).

Thanks for taking a look at this.

Bastiaan