RPM question

[Tim Wunder]

In an effort to eventually upgrade my system from RHL 8.0 to Fedora Core 
1, I'd like to determine what rpms are installed that are not part of 
the origianl RH 8.0 or any of its updates. Essentially, this would be 
any rpm I have installed that doesn't have Red Hat, Inc. as its Packager.
I'm hoping that this can be done using the output from 'rpm -qai' and 
piping it thru grep somehow.
Any ideas?

Thanks,
Tim