Problem with receipient policy and multiple domains on Exchange 2003

I have run into an issue with creating multiple SMTP domains on my Exchange server. I created a *new* receipient policy for the new SMTP domain and it seemed to be working however, the user could not log in through OWA. After doing some reading, I found a MS KBase article that seemed to suggest that any additional domains had to be configured as part of the _default_ receipient policy. I deleted the policy that I had created and then went back to add the SMTP domain to the default policy. When I attempted to do this, I received the following error: The Email address is not valid...check the event log for further c10312e6. I checked the event log and the error message indicates bad SMTP domain but nothing further. I subsequently tried to go back and re add the stand alone receipient policy but I now get the same error for that as well: The Email address is not valid...check the event log for further c10312e6. I also tried running the RUS but this did not help either. So now I am stuck and cannot add the domain. So my question has four parts:

1) How do I resolve getting this SMTP domain added to a receipient policy?
2) Once the issue is resolved, should I add the new SMTP domain to the default policy or to its own policy?
3) Any ideas why the new user I created with the new SMTP domain could not log into OWA when all other users have no problem using OWA?
4) Assuming I can resolve the above problem, what is the best way to host mulitple domains on Exchange 2003. Assuming that each domain would be its own company and not want to see other's GAL, etc.

Thank you in advance for your assistance!
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When you make a change with SMTP domains you need to allow time for it to replicate to the domain controllers. Make sure that you give it enough time before trying to do anything with it.

That said, adding to the default policy is my usual method. You need to make sure that you are formatting it correctly.
It needs to be added in the format:

No idea about the OWA query as I always add them to default policy so haven't come up with that issue.

There are a ton of articles about creating new GALs to seperate GALs.
This is the main one:
You may also want to look at this one:


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