Are you saying that:
1. Your other registrar won't let you set the nameservers for your domain to ns1.dreamhost.com, ns2.dreamhost.com, and ns3.dreamhost.com?
2. You don't want to (or can't) transfer your domain registration to DreamHost?
You can obviously set the IP address of those specific subdomains to whatever IP address ends up being your web server for the domain/subdomain you add hosting for here at Dreamhost, but before we talk about that, is there a reason either of the above two options doesn't work for you?
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