I am having trouble importing an SSL CA certificate to authenticate my mail server.
My mail server is run by Dreamhost, which offers TLS on their IMAP/SMTP servers, but with a certificate signed only by them (not obtained through Verisign et al). I have their root certificate file ndn.ca.crt and it works fine on my computer (I put it in /etc/ssl/certs with an appropriate symlink, and then firefox, pine, etc are able to verify Dreamhost's server). Now I'd like to use it on my new Android phone (4.0.4).
I've tried importing the certificate: I copied ndn.ca.crt to USB storage and went to Settings > Security > Install from device storage. I get a "Certificate name" dialog box with "ndn.ca" prefilled, saying "Package contains: One user certificate"; I touch "Ok" and see a popup "ndn.ca added".
However, when I touch "Trusted credentials", there is nothing listed under the "User" tab. And when I try to select TLS or SSL as the security type in the Email app, I get the message "Setup could not finish: Cannot connect safely to server". If I use "TLS (Accept all certificates)" it works, but of course this doesn't actually protect me against a man-in-the-middle.
Any ideas what could be wrong? I've read the question How do you import CA certificates onto an Android phone? but it seems to be mainly concerned with getting the certificate in a recognized format, and doesn't help me.