I have a customer that are having issues with the SA520. His mail server is set on the DMZ zone. When he tries to connect to the mail server with his web browser the browser points to the SA520 instead of his mail server. This issue does not happen every time he tries to connect to the mail server, but every now and then. The issue is between the LAN and DMZ. The other DMZ computers connect correctly every time, as well as clients from the WAN.