no trackball click with ICS/JB Android emulator

Question

I have a problem, with ICS and JB emulators (but NOT with emulators with older version of Android, for example API 10 = Android 2.3.3.) :

I do not manage to click when in trackball mode ([F6] or [del]), even in home screens.

In onTrackballEvent(MotionEvent event), ACTION_MOVE events are triggered, but not

ACTION_DOWN nor ACTION_UP.

Is there a (known ?) bug with ICS and JB emulators ? Is there something I do the wrong way ?

Thanks for any help.