[Zope] - Can I get the real URL info into the Zope server?

[skip@calendar.com (Skip Montanaro)]

I'm using Andreas' technique of running ZopeHTTPServer behind an Apache
server and using mod_rewrite and mod_proxy to pump requests to it.
Unfortunately, within the Zope environment I lose all indication of what the
original URL was.  For instance, if you access

    http://concerts.dolphin.calendar.com/z/check_request

you'll see a number of URL- and host-related fields:

    BASE0: 'http://127.0.0.2:8043'
    HTTP_HOST: '127.0.0.2:8043'
    PARENT_URL: 'http://127.0.0.2:8043'
    SERVER_NAME: 'concerts.dolphin.calendar.com'
    URL: 'http://127.0.0.2:8043/check_request'

Only SERVER_NAME indicates the front-end server, and that only because I
started the server with SERVER_NAME=concerts.dolphin.calendar.com.

Is there a way to pump the real URL information across the boundary between
the proxy and Zope servers?  In output pages I can't simply generate
server-relative URLs, because the PATH_INFO (or SCRIPT_NAME) is different
between the two servers.  The Zope server doesn't know that /z/... in the
proxy server maps to /... in the Zope server.  Ideally, this would be
something I'd pass in from the rewrite rule, since the mapping between proxy
and Zope servers is established on a per rewrite rule basis.  Apache's
mod_rewrite still has a bit more black magic than I comprehend yet.

Skip