IOCSPAdmin missing

I've been struggling getting the Online Responder configured in my test PKI setup. I used the this 2 tier PKI setup as my model:

http://social.technet.microsoft.com/wiki/contents/articles/15037.ad-cs-step-by-step-guide-two-tier-pki-hierarchy-deployment.aspx

I've been getting the 'Bad Signing Certificate' error. I've uninstalled, reinstalled, reconfigured the Online Responder role several times. Today I found this troubleshooting info:

  http://technet.microsoft.com/en-us/library/cc726376(v=WS.10).aspx

This describes checking the DCOM permissions on like this:

"Using the Dcomcnfg command-line tool, ensure that the Network Service has Activate permissions for the IOCSPAdmin interface."

This seems to be a problem as this interface doesn't exist. I did find the 'IOCSPAdmin' in the registry, but CLSID also doesn't exist in the DCOM. It appears that this interface isn't being created when the role is installed. Is there any way to do this manually? Is there a fix for this?