I installed two GO instances on same server (in different directories) with two different subdomains. Everything works well but I ve found that if you are logged in in one GO and open the URL of the other in another browser tab, you are logged in to this GO as well using another user. If you logoff in one of those GO, you are logged off from the other as well.
It seems to depend on the session coockie, that holds the domain name in the host field, but only / (root) in the path field.
I couldnt find any hint in the docs or in the forum here how to set the path in the session coockie.