permission issue

[Jens]

hi!
something strange happened yesterday and id like to get some help
understanding it. i was showing a friend how permissions work and did this:

as user eg. joe:

cd ~/
mkdir test
chmod og-rwx test
cd test
sudo touch file
sudo chmod og-rwx file

now heres whats STRANGE:
rm -f file

and the file is deleted...this means that user joe deleted a file owned
by root with 700 permissions.

this def. seems counterintutitive to me but id very much appreciate
being corrected.

thanks, jens