Finally got the router configured to support my fixed IP block, huzzah! But for some reason, the Airport only allows clients to gain full-qualified IP services if the client has one of the five fixed IPs – locally assigned DHCP clients, from the Airport’s own DCHP server, appear to gain the appropriate 10.foo.bar.baz number, but can’t see any webbiness or even ping the router – the DHCP LAN is walled off from the fixed IP LAN.
I think this may be due to the fixed IPs requiring a subnet mask of 255.255.255.248 while the DHCP is handing out a mask of 255.255.255.0. I don’t know if it’s possible to configure the Airport’s SNM for DHCP. Hm. Time to hit the boards.