I know ecash has some proxy support but I'm not sure how it works. There are SOCKS proxies and http proxies, and I don't know which it uses. I used a logging httpd proxy to derive the data for the SSL challenges I did this past summer. It might be interesting to post the binary data from some ecash transactions.
The Ecash firewall support works by sending the messages as multipart MIME messages. The browser is then set to hand the application/ecash message the Ecash front end.
I wonder if it would be legal to write shop software which sent such a payment request, took the resulting coins, and deposited them in the bank (if we could figure out all the protocols necessary).
IANAL. What would you hope to gain from creating such a piece of software? --Lucky at -- Mark Twain Ecash Support <mailto:support@marktwain.com> <http://www.marktwain.com/ecash.html>