Interesting! I ran into exactly the same problem yesterday, however before having moved out things and soft-linking them. In my case I suspect that I have prematurely stopped a run with apt-get. It happened actually twice. Once, the device appeared completely unresponsive, so I rebooted, at another occasion it rebooted by itself in the middle of installing a large set of Debian packages. After that I had corrupted files in /var/lib/dpkg/updates which I could not remove. I had to delete the whole image and start all over. I never had such problems before - perhaps it's due to PR1.3 or my internal memory card is getting worn out. However, fsck.vfat didn't find anything wrong, perhaps fsck.ext2 within the image could have resolved it.

At any rate, it's crucial that apt-get is allowed to finish its job. When the device seems to become unresponsive, be patient and don't just shut it down (if that's how it happened to you). Beats me, however, why the file system error should look like NFS problems to the kernel.