RPTR EXPERIENCES UNCOMMANDED ROLL TENDENCY WHEN THE AUTOPLT IS DISCONNECTED.

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I WAS CAPT FLYING. IN CRUISE THE ACFT WAS FLOWN ON THE AUTOPLT AND IN TRIM. THE FO FLEW THE TKOF AND CRUISE SEGMENT. I BECAME PF FOR THE 10 MINS BEFORE DSCNT ONWARD. AT 24000 FT CRUISE; THE ACFT WAS BEING FLOWN IN LATERAL NAV AND VERT NAV MODES. RESPONDING TO A CLRNC TO DSND TO 16000 FT THE ACFT WAS SWITCHED TO VERT SPD DSCNT; SPD BRAKES WERE EXTENDED; THEN STOWED IN THE DOWN POS. THE AUTOPLT WAS THEN DISENGAGED. A ROLL WAS FELT TO THE R. I APPLIED CORRECTION BUT THE CTL FORCE WAS GREAT. THE FLT CONTINUED TOWARDS DEST. WE WERE BEING VECTORED WHILE WE INVESTIGATED THE PROB AND CONTACTED THE COMPANY. THE RUDDER TRIM AND AILERON TRIM WAS MOVED IN AN ATTEMPT TO RELIEVE THE CTL FORCE. AFTER CALLING THE COMPANY AND DISCUSSING THE PROB I DECIDED ON A PLAN WHICH REQUIRED A LNDG WITH FLAPS 15 DEGS. THEN AS THE AIRSPD WAS REDUCED; THE CTL FORCE SEEMED TO INCREASE. THE NEXT CONSIDERATION WAS TO LAND THE ACFT WITH THE FLAPS AND SLATS RETRACTED AT A HIGHER AIRSPD. THE LNDG WAS CONDUCTED SUCCESSFULLY AND MAX BRAKING WAS APPLIED MOMENTARILY THEN NORMAL BRAKES. THE ACFT TOUCHED DOWN AT ABOUT 210 KTS. THE BRAKES WERE HOT BUT THERE WAS NO DAMAGE TO EITHER ACFT OR PERSONNEL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED HE WAS FLYING A BOEING 737-300. HE SAID IT IS UNUSUAL FOR THE CAPT TO CHANGE FROM PNF TO PF ENRTE. IN THIS CASE THE #2 VOR COULD NOT BE MANUALLY TUNED TO THE ILS BECAUSE THE VOR REMAINED IN AGILITY TUNING. THE RPTR HAS FLOWN AS CAPT JUST A LITTLE OVER 100 HRS. HE HAS FLOWN THE B737 AS COPLT FOR OVER A YR SO ESTIMATED HE HAD ABOUT 1000 HRS TOTAL TIME IN THE B737. THERE ARE SEVERAL CONFIGNS OF THE B737 IN HIS COMPANY WHICH WOULD PERHAPS DILUTE HIS UNDERSTANDING OF THIS B737 WITH THE GLASS COCKPIT. HE ALSO HAS TIME IN THE B757 AND B767 AS COPLT AND B727 AS FE. HE WAS NOT SURE WHETHER THE AILERON YOKE WOULD MOVE IF THE AIRPLANE WAS ON AUTOPLT AND THE AILERON ELECTRIC TRIM WERE APPLIED. WHEN THE CTL PROB OCCURRED AFTER HAVING DISCONNECTED THE AUTOPLT HE COULD NOT GET ANY RESPONSES WHEN HE TOGGLED THE AILERON TRIM. THE AILERON TRIM CIRCUIT BREAKERS WERE CHKED IN BUT NOT CYCLED. HE CONTACTED HIS COMPANY MAINT AND FOLLOWED THEIR INSTRUCTIONS TO THE POINT WHERE THEY WANTED HIM TO SLOW THE PLANE. IT STARTED TO GET MORE UNCONTROLLABLE. FOR EXAMPLE; HE TRIED TURNING OFF THE YAW DAMPER AND CHKED THE THROTTLES WERE EVEN AND THE FUEL WAS EVEN IN THE WINGS. THE WINGS WERE CHKED TO ASSURE THE SPOILERS; FLAPS AND AILERONS WERE AS THEY WERE SUPPOSED TO BE. AT THE GATE WITH THE ENGS SHUT DOWN THE YOKE WAS OBSERVED DISPLACED TO THE R ABOUT 7 UNITS. THE RUDDER WAS TO THE L ABOUT 2 UNITS. THE RPTR DID NOT KNOW HOW MANY UNITS L AILERON MOTION IN FLT WOULD BE NECESSARY TO COUNTERACT THE 7 UNIT R AILERON FEEL CENTERING THAT EXISTED ON THE GND. THE NO FLAP LNDG WAS JUST AS HE WAS TRAINED IT WOULD BE IN THE SIMULATOR.