Hi - odd.
I have an exchange 2003 environment. When I (or anyother user) sends a calendar invite to specified users, it mysteriously ends up in another users inbox. There are no forwarding rules, on both the exchange or outlook.
There are 70 users on this exchange, both users are in a different OU.. not that that should make a difference, just giving you some background.
This is not with everyone, only 2 or 3 users, and all get copied to this single user mail box. ONLY calendar invites, not mail.