Rather just use URL parameters. As I recall RFC2616 does not consider a
request with a different cookie a different variant, so even if you
patch your server to allow it to differentiate between cookies, neither
the browsers nor the transparent proxies in the path of the request will
do what you want them to do :(
Well, that truly sucks. If you pass options around in params then whenever someone follows a link posted by someone else, they will inherit that person's options.
I do wish people would read the specification to refresh their memory before summarizing. RFC 2616 doesn't say anything about cookies -- it doesn't have to because there are already several mechanisms for marking a request or response as varying. In this case
Vary: Cookie
added to the response by the server module (the only component capable of knowing how the resource varies) is sufficient for caching clients that are compliant with HTTP/1.1. Expires and Cache-Control are usually added as well if HTTP/1.0 caches are a problem.
....Roy
