Power button causes shutdown when laptop is suspended

Hi all,

By using "gnome-tweak-tools" I managed to make Gnome 3 ask me what I want to do when pressing the power button on my MacBook Air 4.2 (late 2011), i.e.: I am asked if I want to shutdown or suspend or hibernate the laptop.
On the contrary, if the laptop is in suspend mode (e.g. after the lid has been closed), pressing the power button simply initiates the shutdown process. This is rather annoying as sometimes, if I have not been using the laptop for a few time, I can't remember if I shut it down or not and then I press the power button automatically, thus causing the system to halt instead of recovering from suspension.
Can I solve this in any way? Can the power button work as any other key when the laptop is suspended?

Thanks in advance for your help,

w.