B737 Captain experienced violent pitch up as the aircraft is about to intercept the Runway 11 LOC at OAK with the autopilot engaged. Aircraft climbed from 2600 to 3400 FT before control was regained and the aircraft hand flown to a successful landing.

Narrative

Vectored thru final OAK Runway 11 due to minor rain shower over ALCAT; we were @ 2600 FT; heading 090; flaps 5; 145 KTS in IMC. Cleared for the approach I hit the APP button. (Localizer was coming in from left and we were approximately 1 1/2 dots below glide slope). 2 to 3 seconds later the aircraft violently pitched up as if to acquire glide slope. This led to a second or 2 of confusion followed by disengaging the autopilot. As airspeed bled off the auto throttle's kicked in aggressively; exacerbating the pitch. Saw at least 15 degree nose up; vsi +3500; airspeed 120 (-25); and ballooned to approximately 3400 FT MSL; (blew thru glide slope). After disengaging auto throttle's was able to wrestle it back down as ATC started telling us to get down due to some corridor. Considered going around; but was comfortable enough (with distance and altitude) to try and get back in the slot. Began configuring; after some fairly massive corrections we were close enough to parameters that I stupidly tried to reengage the autopilot which didn't work; so I hand flew it in from there; (breaking out shortly after at about 1200 FT) to an otherwise uneventful landing. TOGA was NOT selected.