This is very interesting. When you remove the firewall from the picture who answers for the public IP address? You have a router or do you give the public IP directly to the server?
You are running 8.2.2 so captures are very easy to do. You do not need any access-list for collecting captures.
cap capout int outside match tcp any any eq 25
You can remove any other capture that you have on the unit presently and apply the one above.
If the packets do not arrive on the captures like I read on the thread up above, the ASA cannot do anything about that.
Try the telnet test and do "sh cap capout" and see if you see the packets.
There is a bridge that is attached to the modem. When I called my provider they said everythign is wide open. Tonight I am going to try hookip up the server to the modem with the bridge connected last time I just connected the modem with the server.