As per this thread:
You would set up the domain as if you were going to use dreamhost as your name server, then copy the A records you see in the control panel over to the real name server.
Depending on whether your client hosts mail elsewhere or has other subdomains hosted elsewhere, there could be some issues with mail from the DreamHost mail server and web service calls out from DreamHost since some of the DNS records in the DreamHost DNS may be incorrect.
As noted in the other thread, if your virtual hosting means that your server is switched, you'll have to upate the record on the official name server manually.
If anyone knows of a better way, I'd be glad to hear it since this is what I'm doing right now for hosting a subdomain here and a main domain on another hosting provider.
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