Even though most of my email is coming in un-encrypted, I want to store it on a server somewhere in encrypted form. Is there any solution available that encrypts on the client so that a compromised server still does not mean that my emails can be read by others? (encrypted file systems on the server are not sufficient as the decryption key needs to be on the server as well).
A client that PGP encrypts automatically when storing in a folder would do the trick, together with some batch encryption that encrypts my entire existing folder tree. Have not been able to find either.
Any suggestions? (Linux client preferred, but am interested in other platforms as well)