I am using Flash MX and I would like to apply multiple motion tweens to different portions of the same motion guide. Is this possible?

I am trying to emulate gravity on an object, so its motion accelerates as it falls and decelerates as it moves upwards. I use the ease function to do this and so I require multiple motion tweens. I would like to have one motion guide path in one layer for all the movement of the object and another layer for the object and its various tweens and apply the appropriate tweens to different parts of the motion guide path.