So you are going to be having 2 separate, independant PGP implementations in the same infastructure? Can you not cluster them to make use of the same keys.domain ? The purpose of having the convention of naming them keys.domain is so other companies can look up your public keys, that's pretty much it. If you publish your keys to keys.pgp.com then it won't really matter as they will be able to look them up there instead of your own keyserver