MAX crash when i try to register a callback

    Dario Pizzamiglio
    Mar 07 2010 | 3:59 pm
    Hi all, i'm working on an external with faceAPI. the problem is that MAX crash when i try to register a callback function as in the sample code of the faceAPI SDK... the API call to register the function is
    void * obj_new(t_symbol *s, long argc, t_atom *argv)
{
...
smHTRegisterHeadPoseCallback(engine_handle,0,receiveHeadPose);
... then CRASH
}
    and here the prototype of the function called
    void STDCALL receiveHeadPose(void *,smEngineHeadPoseData head_pose, smCameraVideoFrame video_frame)
{
 post("something");
}
    anyone can help me? thanks all k