Virtual/Dynamic EMail Account Generation Utility

Similar to Craigslist, I need the ability to create virtual/dynamic email accounts on the fly. I need the following services -- a. CreateAccount -- dynamically create an email address. b. AssignUsers -- This service would assign a user to the virtual/dynamic EmailID created in (a). c. SendMessage -- If one of the users in (b) sends a message from their EmailID to their assigned dyanamic/virtual email address, that message is forwarded to the other EmailIDs on the list. So, for example... (a) We create, Serv-090909 on [login to view URL] as an virtual EmailID. (b) Then we assign, JaneDoe and JohnDoe to the Serv-090909 email address. (c) If we receive a email message from JaneDoe to Serv-090909, that email message would be forwarded to JohnDoe I would like the service to be implemented in Linux/PHP as a GENERIC UTILITY that I could easily integrate as a feature into my any web application. Thanks. Darrell