Enterprise Mgr to remote database

Hi Guys,
I have a web app hosted on an external box with my dev box here. both use identical SQL2000 backends. What I would like is to have my Enterprise Manager have both servers registered so that I can work from one interface. No probs getting the local one registered, but how do I register the external DB server? It's not in my domain, but I do have an IP address and Administrator rights on the remote box. This is probably simple, but I must be missing something.
Thanks
MikeJust add your external server as linked...|||Umm . . OK.

1. So New Sql Server Registration gives me the Register Wizard.
2. I enter the IP address manually in the Available Servers field and click add. Click Next.
3. So far, so good. Can't use my current Windows Account info (different domain), so I select SQL Server login info and put in SA account details.
4. I get a Connecting dialog then "SQL Server does not exist or access denied - ConnectionOpen - (Connect()"

Sorry if I sound dense, but . . . . .|||Try using the subdomain.domain address construct rather than IP address.

Example:

somesqlservermachinename.domain.com

I've had problems connecting to one of our remote SQL Servers via IP address (odd, since the same server is in the same subnet as two other SQL Servers that I can connect fine using their IP Addresses). But the subdomain construct works just fine.