As promised, I poked around Cocoon a bit to see how it would handle
Walter's scenario of propagating cookies. As near as I can tell, there
should be a way of working with session contexts to do this, but when I
couldn't connect to the Apache site last night I decided to make a small
application in Cocoon to catch the cookies and append them to the content.
I used the existing HTML generator and added some small cookie handling
logic. Since I was using the merging capabilities of Cocoon to lump all the
pages together coming in this way, I set up a test that uses the parallel
and caching options.

If you use any of these three URLs, you might be able to detect some
differences in responses. Sorry, I didn't set up a stylesheet so everything
is thrown together in one big jumble. Our general internet connectivity is
so bad right now that it probably overshadows everything else but the
different configurations are in brackets beside each URL:

http://137.207.184.118:8080/cocoon/wibs/cinclude-test1 (multiple pages in
sequence)
http://137.207.184.118:8080/cocoon/wibs/cinclude-test2 (multiple pages in
parallel)
http://137.207.184.118:8080/cocoon/wibs/cinclude-test3 (multiple pages in
parallel with caching)

You will probably need to do a view source to make any sense of the
results, but pages that have cookies will have "cookie" elements with the
value of the cookie making up the node. The first section is from the
Privacy Commissioner of Canada and I had to include it because it seems so
ironic that this page uses cookies! The other pages are google, dmoz, and
lii.

You could also add your own cookies with this method, or override the
existing ones before handing them over to a user. The cookie handling
capabilities of httpclient, which is used here, allows you to set different
cookie policies, and I am using the default policy. I noticed that this
rejects the first cookie from google if you use the "www.google.ca" address
since the cookie actually comes from "www.google.com". I assume there are
more forgiving policies for this kind of thing.

Anyway, I can share the files if someone wants to dive deeper into this. My
general experience is that someone will point out the way to do this that
doesn't require coding at the precise moment that I resort to programming
because I can't figure it out directly. So it's possible that the added
piece is not even necessary. Cocoon uses JTidy for converting HTML to
XHTML, and one thing I learned in this process is that this can be
configured fairly deeply. If you look at the source of the rendered page
you will see that the jump from HTML to XHTML is not without some quirks
and this would need some tinkering to handle the different interfaces.

art