24.1.50 + lexical-binding + server.el + server-visit-hook = problem

[Jim Diamond]

While using 23.4 (and some other older versions) I added a hook to
server-visit-hook.  My hook function uses the variable "dir", which is
meaningful at the point where server-visit-hook is called.

However, in 24.1.50, the new and improved server.el has
        lexical-binding: t
at the top of the file, which (apparently) means that dir is not
available to my hook.

Can some emacs guru (or wizard or ...) enlighten me as to what is the
"proper" way of dealing with this problem?

Thanks.

                                Jim