That explains the Airbus setup i guess. Where the innermost spoiler is ground spoiler only, the outermost is only a roll and ground spoiler but not a speed brake spoiler. Similar to the 737 by the way, inner and outer spoilers are ground spoilers, the four middle ones are flight spoilers.
Rear mounted engines are not really used on airline jets anymore, but of course remain the standard configuration for most (all?) pure business jets.