I imagine you would store the messages only once, and reference them for each user that is concerned. If all the references to a message are removed, you can remove the message.

Good point.

I don't know that it would increase the number of messages - something in your inbox is something in someone else's oubox. We would have to decide how each would be managed - if I delete a message in my outbox, would it also remove it from the recipient's inbox? What about the other way around. This could be extended to also 'recalling' a message, where the sender could remove messages from the inboxes of recipients that have not read the message.

Hi,

yes, there is no 'outbox' currently, becuase that would mean we need to manage 2x the amount of messages, and several different states (sent, read, removed), because it is possible that the person you sent a message to will want to remove the message after reading, but you want to keep it.

At the moment, there is no real roadmap for the profile module with major changes or so. The current focus is on getting the 2.0 development more structured and organised, and getting a new development release of ImpressCMS 2.0 ou thtere that fixes a maximum of the known bugs.