4 screws (or 8 screws at worst, if you're using the double screw banana). You could DIY an adapter yourself - buy 4 banana posts then solder bare wire to them - put that in a fancy box if you want
Generally, modern gear likes using a cheap chip-amp solution - and I mean really cheap - sometimes worse than a meager CMoy. They're built to power iBuds, not your fullsize cans =p. Vintage stuff however, the headphone out is tapped directly from the speaker output - think of it as a built in HE-adapter.
I am sure that I read on this forum that someone checked this and a lot of modern amps (decent quality stereo ones) actually still uses the main amp for the headphone jack as opposed to a cheap chip amp?