Your close... Basically, if an email comes in for user@example2.com, which is a virtual host, I want it to go to that users inbox, as well as forwarded on to another account(ie: a blackberry account for their push notification). Now multiply that times about 200 users all forwarding to different accounts, as well as keeping a copy in their inbox for their retrieval when they get back to their office. They still control everything related to the email in their accounts, they just require forwarding to their other accounts as well for some other purpose(mobility etc.)
Currently, the workgroup manager only allows a forward, and that's it. The docs mention Sieve, but state that it does not work for the virtual host aliases. Having two accounts with different names so it forwards to account 2, and to wherever else is just stupid, and unworkable in the corporate world. That would require two email addresses for everyone of these users.
So do postfix aliases handle this specifically? ... and if so where would I find this procedure?.. also, when the server is upgraded, will this will probably be overwritten, and continually be a problem in the future?
This is a fairly standard procedure on any other mail server.