Adrian, thanks for the reply.
Vin, I think it would be better to identify patches by their URL as
found in
http://www.xemacs.org/list-archives/xemacs-patches/
Well, I have these patches in a mail folder, and using gnus it's very
easy to extract the message-id. The message-id uniquely identifies
the message, and we should be able to search the archive based on that
string. I don't really want to have to go to the website every time I
want to refer to a patch which I already have saved and ticked.
Another option is for the mailinglist to add the archive URL to the
message header.
- vin