Hello Mr Acevedo,
There might be some confusion around what you refer to as "SmartCloud iNotes" in your previous message, and I would like to get this clarified to answer your question.
It is possible to have different kind of subscriptions for the different users of the same company.
You can have some users with SmartCloud Engage Advanced and some others with only SmartCloud Notes. There is another version of the SmartCloud Notes service called SmartCloud Notes Entry, which allows users to access their mails through a web browser only.
These 3 subscriptions can have the same internet domain for the Messaging system.
This may be what you are looking for.
In the other hand, the service named SmartCloud iNotes is a different one and can not share the same internet domain, as Vin highlighted in his previous message.