Now ill be the first to admit that this is not an absolutely perfect solution and Ableton should still put in curved automation, however until that happens this is a pretty wiked tool thats going to save you alot of time when it comes to creating curved automation.
This beats using using a billion little linear lines that every-time you want to slightly change the curve you get an aneurism and eventually just throw in the towel and use *insert nearly any other DAW here that has curved automation*
You can get the tool from here: http://www.djtechtools.com/2012/02/16/m ... r-ableton/
The idea is you create the curve that you want inside of Mapulator, then automate mapulators knob in a very simple easy to make linear line how you normally would in Automation. Mapulator then automates the parameters that you want to control according to the graph.