I've been butting my head against this for a while now and can't seem to find the answer.

I'm trying to add an external account that uses IMAP/S on port 993. The server uses an internal self-signed certificate and I am getting an error "Unable to find certification path to requested target". I assume this is related to the fact that the certificate is not trusted. However, I trust it and would like to be able to tell Zimbra to accept it permanently (a la other mail clients).

Can somebody point me in the right direction?