Do you have some information regarding browsers that implement/plan to implement this part of the HTTP 1.1 specification? Additionally, what frameworks have already implemented
The current state is that most browser only fully support the initial Cookie specification by Netscape.
Set-Cookie/Cookie per RFC 2109 are only supported by some browser (I don’t know which) and Set-Cookie2/Cookie2 per RFC 2965 only by Opera.
Set-Cookie
Cookie
Set-Cookie2
Cookie2