Reply to How To warp a "transition" track in Ableton 8?

Just picked up Ableton 8 and am using it for my dance radio show mixes. Can't figure out how to warp a song that has multiple tempo changes in it. An example would be a song starting at 128bpm for the first few bars for mix in, then slowly changing to the songs original 80bpm and then back up to 128bpm at the end for the mix out. I've heard of breaking it up into separate tracks, but am not sure. Any thoughts or techniques for this?