You can "re-set" the variable during the INVOKE_APPLICATION or RENDER_RESPONSE phase. Does that help?
OK. I guess I could write a phase listener to set that again before render response, so that I would be accessing the "next page map" in PageContext. I was hoping for a more Seam'ish way to do it. But, that sounds like it will work.
This sounds to me a lot like the "Flash" scope of RoR and family. Though conversations don't look very heavyweight to me, a flash scope could be nice in order to remove any need to use that "conversationId" (or cid as it is in cvs) parameter.
That segues to a minor gripe of mine, namely the conversationId parameter in the URL: would it be feasable to put the conversationId in a hidden formfield and/or the viewstate instead of the URL?
It *is* kept in the view state ... unless you do post-then-redirect.
And no, what Ryan is describing is nothing like the crappy "flash" context.