No answers, just some questions... (I'm not sure what you're asking.)
Where did the certificate originate? An Apple iPhone certificate? For what? For iOS development? For VPN? For accessing remote web services, on a server? This is the OS X Server 10.6 forum; are you working with certificates with that operating system, or with certificates on an iPhone?
If your OS X Server system has an expired certificate, you'll need to either purchase a new certificate, or generate a new self-signed certificate and load that via the Certificate Assistant and Server Admin tools.