DURING AN ATTEMPTED TAKEOFF ROLL THE CREW NOTED A WARNING LIGHT INDICATING WING SPOILER DEPLOYMENT AND ABORTED THE TAKEOFF. COMPANY MAINTENANCE PERSONNEL DEACTIVATED THE WING SPOILER SYSTEM AND THE WING SPOILER WARNING SYSTEM. AFTER TAKEOFF THE CREW EXPERIENCED ROLL CONTROL DIFICULTY AND RETURNED AND LANDED. EXAMINATION REVEALED THAT THE RIGHT OUTBOARD SPOILER PANEL HAD DEPLOYED WITH NO WARNING. THE ACTUATOR WAS REMOVED AND THE HYDRAULIC SEAL WAS FOUND CUT AND LEAKING AROUND THE PISTON THAT WAS WORN BEYOND SERVICABLE LIMITS.