Thanks, but as I tried to make clear in my original post, it does ROUTE on the lan properly - I can ping, I can send and receive UDP packets (SMS messages), I can even get an initial telnet connection - but the device simply refuses to accept any connections on the web or telnet interfaces from outside the local subnet. UDP communication works fine from any subnet. With telnet, I get a telnet connection, but i’m never presented with a password prompt, and the connection is closed after a couple of seconds. With the web interface, I can contact the server (http socket connection is opened), but again I never get a response.
What it looks like is an access control list that is only allowing administrative access from the class C that the device is in, and I can’t find any where to set who is allowed. Or even to set what subnet the device is in, for that matter (just for DHCP).