Richard Kagerer wrote in with these instructions
for those who need to use this program on Microsoft
Windows:
How to build tcpxd on Windows
Install Cygwin. Select to include "gcc-core" and "automake".
Download tcpxd source from http://quozl.netrek.org/tcpxd/
Extract to cygwin\usr\tcpxd-1.4
Rename aclocal.m4 to aclocal.m4.old
Start Cygwin shell and run:
cd /usr/tcpxd-1.4
./configure
aclocal
automake
gcc tcpxd.c -o tcpxd.exe
exit
Copy tcpxd.exe and cygwin\bin\cygwin1.dll to a directory on your computer
(e.g. C:\Program Files\tcpxd). Run tcpxd.exe (no arguments) from a command
prompt to show syntax.