We have a Catalook based storefront on DNN5.1  and are having problems with the "email a friend" option.

We have traced the problem to WebHost4Life's email servers.  These are locked down such that they can send emails accounts with domain based email accounts.  For example, for our site www.abc.com, we can only send emails from accounts like xxx@abc.com.  By the send friend an email option is configured so that the "from" email address is that of the person sending the email. 

They are doing this to keep spam under control, so they have a good reason.  So, we are looking for recomendations as to what to do.  It looks like our best option is to use an external service that we can use as an smpt relay server.  Suggestions?

Thanks in advance.