You can compile PokerTH using mingw now (as of svn rev. 766).
Grab the mingw installer
http://sourceforge.net/project/showfiles.php?group_id=2435&package_id=240780
and get a copy of the "candidate" of mingw. Install the C++ compiler, and don't forget mingw-make.
Compile qt 4.3.1 and boost 1.34 using mingw. Make sure boost installs the libraries to the boost/stage subdirectory.
In boost/stage/lib, rename boost_thread-mgw34-mt-1_34_1.a to libboost_thread-mgw34-mt-1_34_1.a. This is because the DLL-Version of libboost_thread is required for PokerTH with mingw, if you try to use the other version, there will be a linker error.
Grab the precompiled SDL for mingw
http://www.libsdl.org/release/SDL-devel-1.2.12-mingw32.tar.gz
and the precompiled SDL_mixer for VC
http://www.libsdl.org/projects/SDL_mixer/release/SDL_mixer-devel-1.2.8-VC8.zip
Check all paths for the libs (see pokerth_game.pro).
qmake
mingw32-make
and you are done.
Oh and by the way, this takes an awful lot of time, so make sure you have a TV or something around

.