Common hardware keys (embedded devices) ... and GTK

Hello every one ...

I'm implementing a some features to Minimo,that is already running on arm ...
i'm using the scratchbox to crosscompile ... But i'm needing some
advices about the follow situation:

** I wanna to change the internal focus between the widgets on the
application main window using hardware keys. The problem is I don't
know what common arm hardware keys to use to provide this functionality to
the users (e.g. to press F11 or alt+F4 on desktop), and if I can
capture hardware keys specific on embedded devices using gdk (like in
desktop application) ...

To ilustrate a situation that changes the focus using the keyboard
(hardware key) interactions, the firefox (desktop) users can change
the focus between its 'main entry' and its 'render engine' just
pressing F6 ... try it ...

Thanks in advance