Would you mind sharing what it is that you're trying to do or, if you came from another technology where this type of architecture is common, telling us what it is? Was it that applications are refered to as "contexts"? Did that make them seem like they were meant to be used as components within one application?
Not trying to do anything in particular, the thought just occurred to me as I was reading through the book. Was one of those, "Gee, wonder how
that is resolved?" kind of things. Might be worth one of those "question bubbles" in the book if/when they come out with a new edition.
So now I understand things from the server side, but what about the browser? It doesn't have a DD at its disposal to know where one app ends and another begins. The first time the user accesses the second app, does his browser pass in a bogus session cookie (i.e. the one it got from the first app)? In general, how does the browser keep track of which session cookies to pass to which URLs? Does it go by directory structure, i.e. if it gets cookie A from "/foo/index.html" then it passes A to "/foo/bar/index.html", et. al.?