Is it possible to configure an Airport Extreme Base Station to forward to an external IP address? Our company has a small office but we often work remotely. One of our service providers requires that we access their customer service portal from a known IP address. We don't all have dedicated IPs for our home connection so we were hoping to use our Airport Extreme base station to setup a forward.

I expected to find this in Airport Utility->Network.

There is a section for Port Settings which we're using to forward specific ports to a windows machine on our local 10.0.1.x network. However, I'd like to forward the inbound traffic on a specific port back out to a public IP address so it looks like we're all hitting the portal from the office IP address.

When I try to add another entry the IP address to forward to (labeled Private IP Address) is already set to 10.0.1.

Is this possible with an Airport Extreme?
I don't think this is possible. 

Possibly you could turn on a web server on one of your computers and forward the requests to that from the airport basestation. It then could be forwarded from that computer to the address.