Maybe there is some other bug in this code, that is not in my real server code... i don't know, but it seems to fail more often than the real server...
There is something else, preventing compilation of the Network lib (easy to fix, but you probably should fix it):
The include <cstring> (on my platform (newest g++, ubuntu linux 64-bit)) is missing - you may not need it in windows with VCC or Mingw, but with me, memcpy/memset et cetera are not defined without it. So I had to add #include <cstring> to IPAddress.cpp, Packet.cpp and so on...