We are looking for the same functionality of multiple domain authentication. I run a small business and have client domains I need to authenticate. Now, we're trying to find a workaround, and it would simply be easier for Constant Contact to set up multiple domain authentication. Setting  up a separate account would mean years of emails sent to clients are lost and we would have to reinvent every email we send out and re-upload our contact lists. Not a great way to spend our time. Please, please consider this functionality ASAP. I know I'm not the only one in this boat.😀 ... View more