Use QMAKE_LFLAGS_RPATH instead of QMAKE_RPATH
Removed pthread. Windows does not use pthreads.
Added .EXE to exefiles.
Fix staticlib postfix and prefix and added ranlib.
Set QMAKE_WIN32 to 1

This is actually just a trick to avoid faking 'win32' platform.

In application pro-files you should do like this :

win32: QMAKE_WIN32 = 1

isEquals(QMAKE_WIN32, 1) {
    // Windows stuff
} else {
    // Non-Windows-stuff
}