[Pharo-dev] Listening for shift key pressed

Hi, In our project we would like to trigger some actions when user presses down/up Shift button. But we didn't find how to do it. It seems that such keys as Shift, Capslock, Ctrl are event modifiers in Pharo, that apply on already existing events (in HandMorph>>generateKeyboardEvent: evtBuf). Do you have any ideas or maybe have experience concerning described problem? Thanks in advance. Cheers, Alex