Actually, you can accomplish this yourself quite easily from within the admin panel
In the instructions below I am assuming that you did not initiate a registration transfer of abxzyzzy.com during the sign-up procedure, but merely specified that domain as one you would like to host here at DreamHost.
Firstly, remove abxzyzzy.com from the DreamHost system by going to Domains -> Manage Domains in the panel and clicking the small [X] next to abxzyzzy.com (in the Domain column).
Now you can add cdffcde.com to the DreamHost hosting system. On the same panel page as above, click Add New Domain / Sub-Domain. Enter cdffcde.com in the Domain to host: text box and click Fully Host This Domain Now!
This is all you need to do on the DreamHost end, but you will need to configure the DNS for cdffcde.com to point at the DreamHost DNS servers. To do this you will use whatever configuration utility your registrar provides and set the DNS servers to the following;
After you have done this it will take a day or so before the new DNS information propagates around the Internet and your domain is fully usable.
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