[Qt-interest] Need to show a menu item with disabled look but functional

[livubuntu at lalescu.ro]

Hello!

I would like to present to the user of my software a menu, with a few  
actions disabled. But I want that if the user presses these disabled  
actions, he gets a message box to say that they must be enabled from  
the settings.

So, I want an enabled action, but with disabled look. Is that possible?