There's already a 3rd party TCP/UDP DLL for use with DBPro which you can grab from here:
http://mainframe39.mikeasoft.com/junk/tcpudp.zip (includes documentation)
Use that for all the client side communications in DBP and write your server in a different language, like C++ or Java.
I'm currently working on converting one of my projects to using straight TCP instead of DirectPlay and writing a server for it in Java, for the specific purpose of being able to have a multiplatform server, with Linux as the main intended hosting platform.
How much ham could a hamster stir, if a hamster could stir ham?