I'm setting up ASA5540 to replace PIX525. I have a problem, traffic is not flowing from the DMZ to Outside interface. I enabled ping from the outside interface to dmz and debugged icmp trace. This is what i found, "ICMP echo request untranslating Outside:172.18.124.3 to DMZ:exchange
ICMP echo request from Outside:172.18.124.1 to DMZ:172.18.124.3 ID=1024 seq=24576 len=32"
Simply, there was no reply from the DMZ. And when i ping from DMZ to Outside, i dont see any traffic passing in ASA. Please help as my emails are not going out. Attached is my configuration file.