[gtkada] Cannot move Gtkada Canvas Item

[Michael González Harbour]

Hello,

I am using a Gtkada Canvas under version gtkada-3.4.2-gpl. If I move a 
Canvas_Item with the mouse very far to the right then I cannot move it 
back. I can click on it and the appropriate callback is invoked, but I 
can no longer move it.

It also happens with testgtk.

Is there any workaround?

Thanks,

Michael González