B767-200 FLC EXPERIENCES MULTIPLE GPWS ALERTS DURING VISUAL APCH TO RWY 10L AT SFO.

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APCHING SFO; THE ATIS INDICATED THAT VOR B APCH IN USE VOR RWYS 10L&R. THE SURFACE WINDS WERE RPTED AS SE AT 4 KTS. THE ATIS REMARKS SAID THAT THE WIND AT 1500 FT WAS 30 KTS. WE TALKED ABOUT THE VOR APCH AND THE ALTS ASSOCIATED WITH IT EVEN THOUGH THE SKY WAS CLR AND THE VISIBILITY WAS GOOD. WE ALSO TALKED ABOUT THE POSSIBILITY OF WINDSHEAR. WE WERE VECTORED TO DOWNWIND AND ASKED IF WE HAD THE ACFT AHEAD IN SIGHT. WE DID; AND WE WERE THEN CLRED FOR THE VISUAL APCH TO RWY 10L. I TURNED FINAL AND LINED UP WITH RWY 10L AND BEGAN TO DSND USING THE PAPI. AS WE DSNDED; THE WINDS BEGAN INCREASING ABOVE 30 KTS. AS THE WIND INCREASED; I OBSERVED MYSELF GOING HIGH ON THE PAPI. I DROPPED THE GEAR AND FLAPS TO RECAPTURE THE GLIDE PATH. WE HAD LIGHT TURB THAT CAUSED VERT SPD AND AIRSPD FLUCTUATIONS. AS WE CROSSED THE COASTLINE THERE IS AN AREA OF HIGH TERRAIN. OVER THIS AREA WE GOT A GPWS 'TERRAIN' WARNING. I WAS ON THE PAPI AND NOTICED MY VERT SPD WAS ABOUT 1200 FPM DSNDING. I CONCLUDED THAT THE COMBINATION OF MY DSCNT RATE AND THE RAPIDLY RISING TERRAIN CAUSE A CLOSURE RATE PROB THAT SET OFF THE WARNING SO I SHALLOWED MY DSCNT. THE TERRAIN WARNING SOUNDED AGAIN. I WAS STILL ON THE PAPI; THE RWY WAS IN SIGHT BUT I COULD NO LONGER SEE THE HIGH TERRAIN AS IT WAS BENEATH OR BEHIND US. AT THIS POINT I OBSERVED MY RADIO ALTIMETER READING 850 FT. I BEGAN TO ADD PWR AND RAISE THE NOSE AS THE WARNING SOUNDED A FINAL TIME. THE TWR ISSUED US A LOW ALT WARNING AND TOLD US TO CHK OUR ALT IMMEDIATELY. I NEVER ONCE RECALL BEING LOW ON THE PAPI THROUGHOUT THE ENTIRE APCH. THE ACFT WAS THEN RESTABILIZED PRIOR TO 500 FT AND A NORMAL LNDG WAS MADE.