See, e.g.:

• http://stackoverflow.com/questions/20457071/ssl-cetificates-os-mavericks
• http://curl.haxx.se/mail/archive-2013-10/0036.html

The CA bundle stuff generally doesn't seem to work on Mavericks, and certs need to be added to the keychain instead. We should make some kind of effort to:

• document this;
• detect it ("you're running Mavericks but this won't work?");
• maybe prompt to fix it ("do you want to add the certificate to your keychain?").