ok, thanks for the picture - I think that's a lilypad accelerometer toward the knuckles. That already has a diode (LED actually) to drop the voltage.
Although the accelerometer works fine, the datasheet also mentions that at higher voltages, the accelerometer is more sensitive, which is what I do not want at all.
I don't think you should worry about sensitivity. the x, y, and z readings are coming in as 10 bit numbers - you can just scale or translate them however you need to.