*  Using the default svn config (with store-auth-creds = yes), checkout/update your repository. Doing this will cache the ssl CERT that you are unable   to cache once you disable store-auth-creds.
* Edit the ~/.subversion/config file as follows:

      [auth]
      store-auth-creds = no

* Delete any relevant caches of from ~/.subversion/auth/* EXCEPT for the ones in ~/.subversion/auth/svn.ssl.server (this is where the CERT is cached)