Is Google Using its own SSL Certificates?

Checking my HTC Hero custom Android 2.1 ROM mobile this morning I was alerted to a security problem. The browser certificate on google.com was throwing up security warnings. On closer inspection it seems the certificate was issued by the "google interenet authority".

I really don't like the smell of this. Either Google are trialing something that has accidentally been exposed, or more likely, there is something malicious going on with the custom ROM.

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