unknown user

I have never noticed this before...when I pull up the info for a folder it shows my user, unknown and everyone. My account and the everyone I understand--what is the unknown and why can't I change it(yes I have unlocked everything and it is still grayed out or just won't change the options of read, read&write, write only (drop box)).

Is this somehow related to the root user??? Thanks for any explanation on this as it seems strange to me if this is not the explanation.

Early on, Leopard had a lot of issues with permissions, partly which I think stemmed from upgrading machines running Tiger to Leopard. What you are seeing sounds like the same weird things I had going on myself.

To try and fix, download an app called ACL Fix. This will hopefully repair this properly. Worked great for me. Be sure to backup your files first.
Xnation