Comment 119 for bug 211631

re #100:
> - hacking the shutdown sequence to make it unmount network filesystems earlier (for example moving S31umountnfs.sh to S14umountnfs.sh in /etc/rc[06].d) : will fix it if you aren't executing anything on those network filesystems

This is not safe, as at S14 applications might still have open files on those mounts. It is way better to have:
 S20sendsigs
 S25umountnfs
 S26wpa-ifupdown

in order to first close application, then unmount filesystems and then kill networkmanager. Sorry for the additional noise in this bug, but I have not seen this better fix mentioned before.