I have phoenix set up on an internal network. 18 users have their own blogs. However, the 18 are all on thin clients of the same linux terminal server. When they change tab in admin, or when they click to save a post, there is a good chance of them finding themselves logged in as someone else!

example
Tom logs in and goes to the back office. It says logged in as Tom. He writes a post and clicks save. It says logged in as Dick. He now has access to Dick's blog.
Meanwhile Harry is managing to stay logged in as himself, but is getting the basic skin, instead of the one the others are getting. I haven't taught them how to change skin yet, and this is the first lesson of using b2evo. Skin changing is disabled on the blogs.

I think it has something to with cookies, but the cookies should surely be going into the home directories, and therefore be independent of each other. This is obviously not the case.
And why are some users not getting the skin?

I'm confused by the haphazard nature of what is going on!