I agree completely with Camelot: don't even go there.
Server 1.2v3 has nothing to do with any current version of OS X, server or client.
You would do better to put (Yellow Dog) Linux on there, at least you'd be learning
something relevant - re: Linux, KDE, bash, X11, etc.
http://www.terrasoftsolutions.com/support/hardware/
If you want it to be OS X Server, then yah, take that box back and save yourself really a waste of time and tremendous headaches that will largely lead you to what are now complete dead-ends for that product. Get 10.3 server, but even better, maybe think about a way (in your setup) to run server on your MDD: 10.4 server will run on a MDD G4 just fine, I was doing that for the past couple of years. Put enough RAM in it, and put new hard drives in it, and you'll have an enjoyable experience instead of... pointless pain.