I don't know what it is called. But I saw him do it on a video. It's a classical guitar move. Looks like something a harp player would use. Spread out your first three fingers, and curl them a little bit. Then rotate your wrist down. As the first finger goes from high e to b the next finger should just be starting. He brings up the neck of his guitar when he does this, so the fret board is more vertical, this helps for this part and the outro. It's not a really easy song. Great fun tho, doing it for my Highschool talent show. No one but me wants to do the solos! I don't know if this will help, but good luck!

Oh and by the way how many guitar players are you using? and how are you doing the druming and such? 2 drummers? the singer with those shaker things?