Sharepoint authentication problem - AD Issue?

I've got a sharepoint 3.0 site running and have gone through all of the usual steps to get annonymous access running, with no luck.*

W2k3 Ent, sql 2005 stand db

I'm using windows authentication, on a domain/AD.*

WSS is in a farm (one web, one db server at this point, both member servers).

App pool is running under network service, but same issue if run under a domain account that is admin on all farm servers.

Intranet zone users pass through/authenticate fine (url as machine name), but if using the ip, or the FQDN, users get prompted.

Regardless of zone, kerbos, ntlm etc, I can not get annonymous access.

I'm not an AD guy - is there an AD/Policy setting that would be preventing me from allowing Annonymous access?

No problems allowing it for a standard website, just under WSS.

I will eventually need to create a registration page and use a mssql db, but for now I'm simply trying to grant read/view.

Thanks for the help - EZ