Not according to the way I read the Anti-Spam Policy and the information on the DreamHost Abuse Center.
From the Anti-Spam Policy:
While there may some arguable ambiguity in some of this, the information in the DreamHost Abuse Center makes it pretty clear to me:
To me, that is pretty clear: If is is not provable confirmed opt-in, and in every other way compliant with DH's Anti Spam policy, and is in any way connectible to your DH hosted site, it could result in your account being terminated. And really, that makes perfect sense if they are serious about not being associated with spam operations.