The certificate store is in: /System -> Library -> Frameworks -> CoreFoundation.framework -> Versions -> A -> Resources -> RootCerts.pem
Appending the PEM format key to the end of this file will fix this problem. Note that this requires root and, as always, you should double-check everything before hitting enter. In particular, if you use cat make sure that you don't overwrite that file using > instead of >>. If your certificate isn't in PEM format (mine was DER), you can convert it with OpenSSL. First test with:
openssl x509 -in my-cert.cer -inform DEN -textIf that displays the expected info, then:
openssl x509 -in my-cert.cer -inform DEN -out my-cert.pem -outform PEM[Editor's note: I have not tried to test this as it would first require creating my own SSL certificate ... and I wouldn't know where to start with that task!]

