not sure if this belongs in this forum or the OS-X Server ones, anyway here goes

am having a problem with IP Address' and OS-X Server 10.1.5.
i have a G4 DP-450 which i use for internal WebObjects development. i have a static IP address setup on the server (192.168.0.21) and when i try and access the website from any other machine on the network http://192.168.0.21/cgi-bin/WebObjects/AppName it works fine.

However, i sometimes take the server and a 17" Apple LCD on the road for when i do demonstrations to clients. This is where the problem lies.
For some reason, if the server isnt plugged into a network, it drops the IP address (even though i have set it up as static in the System Preferences), therefore i cant access it using the URL mentioned above. the only solution so far is to carry along a 5port powered hub and some cat5 and it seems to work again.
Using http://localhost/... dosnt seem to work either

can someone explain why it does this? And if there is an easier solution to rectify this problem?
Im going to be purchasing a powerbook in the future and dont really want to be carrying a hub around to do demos - cause it kinda defeats the purpose

thanks