Does anyone know this effect?
It is with greenscreen.
And how is the effect called, and is it in Adobe AE CS4?
I use Mac and Windows.
That's a simple gradient burst stroke layer style. You cannot apply it in AE, but if you import a Photoshop file that has it, the style will render correctly even in AE plus it can be copy&pasted onto otehr items. Anotehr way would simply be to use Glow, ramp up the intensity and play with the A and B colors and the cycle repetitions. A refined method would be to use the glow in its basic form, but then apply Colorama to get more color regions.
You could also try Image Lounge Border Patrol.