How to upgrade certificate on RHEVM application

Hello,
I'm managing a RHEVM 4.0 server. We need to upgrade the web app certificate from the default PKCS #1 SHA-1 with RSA Encryption to SHA-256.
Self signed certs are ok.
I believe there's a way to do that from a command line on the RHEVM server.
What are the steps to do that?
Thanks,
Paul