Saturn Transmission Code Help

Hi, I have a '96 Saturn SL2, great car with no problems except this: I
have a check engine light on, had it scanned and comes up with code
P0733 (trans 3rd gear error) Does anyone know the procedure to fix
this? The tranny does shift funny out of 3rd soemtimes so its a real
code. I just know where to start..thanks in advance!
Jay