2.3exp: help with readers.conf

[John P Speno]

I'm trying to configure my readers.conf file to allow the following access
in INN 2.3exp:

1. readers from *.foo.com may read and post without authentication.

2. readers from {list of many hosts in foo.com} may read but not post by
default. If they choose to authenticate themselves they can read and post. 

3. readers from everywhere else MUST authenticate (using radius), and once
authenticated, may read and post.

I've tried several things to get parts 1 and 3 working, but haven't had any
success.