Agustin-
You can send/receive MIDI information with the ES-1, but to get it to work w/ external software, you may (or may not) need a "translation" layer in between the ES-1 and Ableton Live. I don't own Ableton, so can't answer how configurable it is.
If you're on Windows, you can use a program like MidiOx (
http://www.midiox.com/) to "transform" your midi messages. You might also want to use MidiYoke in conjunction with it.
Basically, you can view the ES-1 midi messages that come in (as NRPN messages). You can then send/map them to whatever format Ableton needs.
You might want to search for the ES-1 NRPN implementation guide to determine how you want to map info to Ableton.
I've seen other people try to accomplish this in the past, so you can probably google / search around for someone that's already solved this. Maybe try posting on the electribe section of
korgforums.com or on an ableton live message board?
Good luck!
-Jeff