Enabling SMTP port for mail security appliance in the DMZ

[PRICE_ETIENNE]

Is there a reason why a mail security appliance that's located at the DMZ cannot send mail to outside of my organization? Port 25 is enabled on the firewall. SmartView tracker does not show dropped smtp traffic from the host. Even a simple telnet from the appliance on port 25 is dropped.

Any suggestion would greatly be appreciated.

Thanks