just as an extra experiment I tried entering 'root' from where I was and re-running the cat.... command=>

home/user # root


BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

Nokia-N900:~# home/user # ls -l /etc/sudoers.d/bluetooth-pan-tethering.sudoers
-sh: home/user: not found
Nokia-N900:~# ls: /etc/sudoers.d/bluetooth-pan-tethering.sudoers: No such file or directory
-sh: ls:: not found
Nokia-N900:~# /home/user # cat /etc/sudoers.d/bluetooth-pan-tethering.sudoers
-sh: /home/user: Permission denied
Nokia-N900:~# cat: can't open '/etc/sudoers.d/bluetooth-pan-tethering.sudoers': No such file or directory
> /home/user #