Xmlrpc4r and https certificates?

I have a small script that uses xmlrpc to connect to a server, and
while I can enable use_ssl, I can’t see how to tell the underlying
https object where to find a (self-signed) certificate.

hints?

Do I have to subclass the xmlrpc4r client to get access to
the http object so that I can call cert_store= ? Or am I
missing some piece of the interface? Should this apparent
rough-edge to the ssl implementation be considered a bug?

I’d love to take credit for being so security conscious, but net/https
is insistent about printing the warning:
warning: peer certificate won’t be verified in this SSL session.

thanks,
-neil