Comment 7 for bug 663069

I'm still seeing this on 12.04, but not on 13.04. Reproducible as follows:

me@laptop ~/temp $ mkdir ro rw aufs
me@laptop ~/temp $ touch ro/dummy
me@laptop ~/temp $ sudo mount -t aufs -o dirs=rw:ro=ro none aufs
[sudo] password for me:
me@laptop ~/temp $ ls aufs/
dummy
me@laptop ~/temp $ rm aufs/dummy
rm: cannot remove `aufs/dummy': Operation not permitted
me@laptop ~/temp $

On 13.04 I don't get the error message and the file is 'deleted' (i.e, a whiteout file is correctly created). Looks like the bug fix hasn't been ported to the LTS release, but probably needs doing so.