I've been wondering if there was anything like "proper" forwarding in gnupg-agent, and thus at least signature support over SSH connections for remote mail clie

I've been wondering if there was anything like "proper" forwarding in gnupg-agent, and thus at least signature support over SSH connections for remote mail clients. My use-case: I have a shell server which receives my emails. I use a local client (mutt) to read my mails, but I do not want to save my private key on the server, because it is not 100% under my control. The idea is that my physically local box would hold my private keys, and the agent would simply forward the to-be-signed data from the remote host to my local system, and transmit the signed data back. When I send encrypted emails, at least those I can easily do on my physical box and send the file over first. It's a bit of an inconvenience, but I can live with that. Being able to sign my mails on that remote shell box without actually putting my keys there is the one thing I'm looking for. I found some kind of hack for this a year or so back, but now I can't even remember what google-fu I had to employ.