Robbbert,
I had the same problem as Shideravan but with dial-up went to my Library and downloaded a zip of your github.com/Robbbert/messui.

When I tried to compile it on a WinXP SP3 system with mingw and Python2.7.3 installed, I ran into errors. The first one was that pcap.h could not be found. On my system, the 3rdparty\winpcap\Include directory isn't being found.

I start compilation with

set path=C:\mingw\mingw64-w32\bin
set PATH=%~dp0bin;%~dp0i686-w64-mingw32\bin;%~dp0Qt\bin;%PATH%
set QT_PLUGIN_PATH=%~dp0Qt\plugins
SET CWD=%~dp0
assoc .py=Python.File
ftype Python.File=%~dp0bin\python.exe %1
make32 TARGET=mess OSD=winui

Any suggestions?