I want to point only one subdomain of my another domain, hosted somewhere else, to my dreamhost account. A have access to dns record and have added A field for subdomain to point to dreamhost server, but I can't make dns entry in dreamhost control panel. I have tried to add this subdomain entry like any other domain/subdomain, but I`m getting error message: Can't add domain: you don't have permission to add to myanotherdomainname.com.

Any help is appreciated. Thanks.