Why when I tried to enable the Remote Web Management for DSL-G604T ( I am aware of security implication for doing that ) a message popped up saying :
Invalid IP address 0.0.0.0
Click on Product Manual and you'll see this on page 61...
"...To enable remote management of the Router, select the Enabled radio button for either Remote Web or Remote Telnet Management and type the IP Address and Netmask of the remote network or system used for management....:"
So you need to enter the IP address of the location from where you'll be managing the device.