I have an ASA 5510 with a DMZ port sub-interfaced to 3 ports. The 3 interfaces are set up the same with security level 50. The outbound rules for the interfaces are the same except obviously for the source. On the first and second sub-interface i can get to the internet but on the 3rd interface i can not. When trying to access the internet i get a deny message in the syslog. The ASDM reports it as the result of an implicit rule. As far as i know, this should be allowed since it is going to a less secure interface.