Here's one I've had a few times now. Happens on both iPod and Incredible, so it seems to be server side. I was having trouble getting calendar to sync, so on the web console, I told it to reinitialize my user. When I synced, all contacts, mail. appt removed (as they should) then started to repopulate. When the mail repopulated, instead of my inbox, it showed me a subfolder I have setup for NGW list mail. On both devices it says it's the inbox, but it's clearly not. Have seen this a few times now, a fresh load of the Mobility Pack on a fresh server seems to be the only cure.