FO OF A FOKKER 100 HAD STALL WARNING DURING A VISUAL APCH DSCNT DUE TO AUTOPLT COUPLING TO A HIGHER THAN NORMAL GS CAUSING THE ACFT TO PITCH UP TO FOLLOW IT.

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I WAS THE CAPT OF A SCHEDULED AIRLINE FLT MAKING A DAY/VMC VISUAL APCH. MY FO WAS THE PF AND HE WAS HAVING A HARD TIME LOSING ALT TO MAKE THE FIELD. WE WERE IN A FLT IDLE DSCNT USING FULL FLT SPOILER. OUR RATE OF DSCNT WAS STILL NOT ADEQUATE SO MY FO ELECTED TO SLOW THE ACFT; LOWER THE LNDG GEAR AND LOWER FULL FLAPS. VREF WAS BUGGED AND THE ACFT WAS SLOWED TO VREF. THE FO ARMED THE APCH MODE OF THE FLT DIRECTOR. SOON AFTER THAT; THE AUTOPLT RESPONDED TO A FALSE GLIDE PATH AND PITCHED UP. THE STALL STICK SHAKER ACTIVATED AND DISCONNECTED THE AUTOPLT. THE FO TOOK MANUAL CTL AND LOWERED THE NOSE TO REGAIN A COMFORTABLE AIRSPD MARGIN. DSCNT WAS CONTINUED UNTIL GS INTERCEPT AND THE REMAINDER OF THE APCH AND LNDG WERE NORMAL. THE PROB WAS CAUSED BY A LATE DSCNT CLRNC AND AN ATTEMPT TO CONTINUE A STRAIGHT-IN VISUAL APCH INSTEAD OF MAKING A 360 DEG TURN TO LOSE ALT. CONTRIBUTING FACTORS WERE THE FO'S CHOICE OF FULL FLAPS AND A SLOW APCH SPD SO THAT THE DSCNT ANGLE WOULD NOT BE AS STEEP. WITH THE APCH MODE SELECTED; THE ACFT PITCHED UP TO CAPTURE A FALSE GLIDE PATH. THIS WAS ALSO NOT NECESSARY TO DO FOR THE VISUAL APCH.