When updating from firmware version older than 1.3.12 errors might occur while uploading the firmware.
Here is one example:
install: cannot stat `/lib/modules/3.2.0-4-686-pae/kernel/fs/aufs/aufs.ko': No such file or directory
The errors are related left over files from previous versions. The new update mechanism is cleaning up these files before.
If you experience this issue when updating to 1.3.12 and want to fix it on your own, ou can remove the file /rw/var/lib/initramfs-tools/3.2.0-4-i686 from your system and retry the update.